2024/10/10 更新

写真a

サトウ タクロウ
佐藤 拓朗
所属
理工学術院 理工学術院総合研究所
職名
特任研究教授
学位
博士

経歴

  • 2020年04月
    -
    継続中

    早稲田大学理工学術院総合研究所   特任研究教授

  • 2014年04月
    -
    2020年03月

    早稲田大学   基幹理工学部/大学院基幹理工学研究科   教授

  • 2004年
    -
    2013年04月

    早稲田大学 国際情報通信研究教授   大学院国際情報通信研究科/国際情報通信研究センター

  • 2000年
    -
    2004年

    キーストリーム代表取締役社長

  • 1995年
    -
    2004年

    新潟工科大学 教授

  • 1973年
    -
    1995年

    沖電気工業株式会社プロジェクトリーダー、主幹研究員

▼全件表示

学歴

  •  
    -
    1994年

    新潟大学   大学院自然科学研究科   博士(工学)  

所属学協会

  •  
     
     

    IEEE

  •  
     
     

    電子情報通信学会

  •  
     
     

    日本シミュレーション学会

研究分野

  • 情報ネットワーク

研究キーワード

  • 次世代移動通信、無線通信、LSI設計、通信プロトコル、通信ネットワーク、国際標準

受賞

  • 工業標準化事業表彰

    2017年10月   経済産業省  

  • テレコムシステム技術賞

    2004年04月   電気普及財団  

  • 関東発明賞

    1992年04月  

  • 関東発明賞

    1990年04月  

 

論文

  • GNSS Spoofing Detection Using Multiple Sensing Devices and LSTM Networks

    Xin QI, Toshio SATO, Zheng WEN, Yutaka KATSUYAMA, Kazuhiko TAMESUE, Takuro SATO

    IEICE Transactions on Communications   E106.B ( 12 ) 1372 - 1379  2023年12月

    DOI

  • A Predictive Approach for Compensating Transmission Latency in Remote Robot Control for Improving Teleoperation Efficiency

    Yutaka Katsuyama, Toshio Sato, Zheng Wen, Xin Qi, Kazuhiko Tamesue, Wataru Kameyama, Yuichi Nakamura, Takuro Sato, Jiro Katto

    Proceedings - IEEE Global Communications Conference, GLOBECOM     6934 - 6939  2023年

     概要を見る

    Transmission latency presents a significant challenge when operating remote equipment, such as a robotic arm. To address this, we developed a platform and conducted experiments to reduce transmission latency to near-zero levels. These experiments employed Long Short-Term Memory (LSTM) to anticipate future motion trends, leveraging both the controller's movement variables and Electromyography (EMG) data from the operator's arm muscles. Our findings indicate the potential to decrease transmission latency by approximately 500ms. Additionally, our research confirms a direct correlation between prediction accuracy and the brevity of prediction time, suggesting that shorter prediction times yield more accurate results when using EMG. In the context of video transmission for a remotely located robotic arm, we applied video prediction techniques using the Predictive Coding Network (PredNet) to counter network latency. Our results suggest that these predictive methods can effectively compensate for a latency period of 300ms, thereby highlighting their potential for reducing transmission latency in remote robotic operations.

    DOI

    Scopus

  • LSTM-Based GNSS Spoofing Detection for Drone Formation Flights

    Zheng Wen, Xin Qi, Toshio Sato, Kazuhiko Tamesue, Yutaka Katsuyama, Kazue Sako, Jiro Katto, Takuro Sato

    IECON Proceedings (Industrial Electronics Conference)    2023年

     概要を見る

    In the rapidly evolving logistics industry, drones are becoming indispensable for automated delivery operations. As drone traffic escalates, formation flying is being explored to enhance operational control and increase drone density, thereby reducing the space they occupy. Drones typically rely on Global Navigation Satellite System (GNSS) positioning information for autonomous flight. However, civilian-grade GNSS devices are susceptible to spoofing via Software Defined Radio (SDR), posing significant challenges. In this study, we introduce a novel approach to detect GNSS spoofing by leveraging the multiple GNSS information available from each drone during formation flight. Our investigations, involving two GNSS receivers spoofed by an SDR, reveal that spoofing results in a calculated distance between two receivers that is smaller than the actual value. Capitalizing on this characteristic, we designed simulations of formation flights involving two and five drones. We also developed a GNSS spoofing detection method using the Long Short-Term Memory (LSTM) network. The performance of our spoof detection method was evaluated using simulation data. The results demonstrate that using multiple GNSS data from drones in formation flight significantly enhances performance, achieving an F1 score of 0.96 or higher. This study underscores the potential of our proposed method in improving the security and reliability of drone operations.

    DOI

    Scopus

  • GNSS Spoofing Detection using Multiple Sensing Devices and Decision Tree Classifier

    Xin Qi, Toshio Sato, Zheng Wen, Masaru Takeuchi, Yutaka Katsuyama, Kazuhiko Tamesue, Kazue Sako, Jiro Katto, Takuro Sato

    IEICE Proceeding Series   72   O3-5  2022年11月

     概要を見る

    For next-generation logistics systems using autonomous vehicles and drones, spoofing of the GNSS location data induces serious problems. Although signal-based anti-spoofing has been studied, it is difficult to apply to current commercial GNSS modules in many cases. We investigate possibilities to detect spoofing of GNSS location data using multiple sensing devices and a decision tree classifier. Multiple features using the GNSS, beacons, and the IMU are defined and create a model to detect spoofing. Experimental results using learning-based classifier indicates the higher performances and generalization capability. The results also show that distance from beacons is useful to detect GNSS spoofing and indicate prospects of installation for the future drone highways.

    DOI

  • Design and Implementation of Ledger-Based Points Transfer System for IoT Devices in LPWAN

    Xin Qi, Keping Yu, Toshio Sato, Kouichi Shibata, Isao Konno, Takanori Tokutake, Rikiya Eguchi, Yusuke Maruyama, Zheng Wen, Kazuhiko Tamesue, Yutaka Katsuyama, Kazue Sako, Takuro Sato

    Wireless Communications and Mobile Computing   2022   1 - 13  2022年08月

     概要を見る

    Distributed ledger technology is becoming popular these days because of its high confidentiality, decentralization, and nontampering. It is suitable for replacing centralized security disadvantaged point transfer systems. Low-power wide area network (LPWAN) is capable for long-range communication with low-power consumption. The iconic features like wide area coverage and long battery-powered duration make it best to combine with large-scale IoT application deployment. In both industry and academic field, such combination of LPWAN and point transfer system is highly attended. However, the ledger management system generates too much data that low-bandwidth network such as LPWAN can hardly handle; meanwhile, the processing power’s requirement for small IoT devices is challenging. Towards addressing these issues, we design a packet transmission optimizing mechanism for a ledger-based point transfer system (LPTS) in LPWAN to reduce overall data traffic and build a simulator to evaluate its performance. Moreover, we have implemented the system and evaluated in field experiment.

    DOI

    Scopus

  • AI-Based W-Band Suspicious Object Detection System for Moving Persons: Two-Stage Walkthrough Configuration and Recognition Optimization

    Zheng Wen, Keping Yu, Xin Qi, Toshio Sato, San Hlaing Myint, Kazuhiko Tamesue, Yutaka Katsuyama, Hironori Dobashi, Yasushi Murakami, Ikuo Koyama, Kiyohito Tokuda, Wataru Kameyama, Takuro Sato

    Wireless Communications and Mobile Computing   2022   1 - 16  2022年06月

     概要を見る

    In recent years, terrorist attacks have been spreading worldwide and become a public hazard to human society. The suspicious object detection system is an effective way to prevent terrorist attacks in public places. However, traditional systems face two main challenges: First, they need to conduct security checks at the entrance one by one, which leads to crowding; second, they rely heavily on screeners’ ability to understand security images, which can easily lead to misjudgment. To address these issues, we propose an AI-based W-band suspicious object detection system for moving persons that can perform a two-stage walkthrough screening for suspicious objects in an open area to maintain high throughput. The 1st screening uses millimeter wave radar and cameras to automatically screen suspects who may have concealed suspicious objects in an open area. The 2nd screening involves security personnel using a hybrid imager with active and passive imaging capabilities to identify the specific suspicious objects carried by the suspect. Convolutional neural network (CNN) based artificial intelligence (AI) technology will be used to improve the accuracy and speed of suspicious object detection. We performed an experiment to validate the proposed system. The usability and safety of the system are demonstrated by recognition rate (aka accuracy rate) or both recall and precision rate. In addition, in the process of improving the suspicious object recognition rate by AI techniques, we use generative adversarial network to help build a suspicious object database and successfully validate the effectiveness of the method and the factors affecting the suspicious object recognition rate to optimize the system.

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • 300GHz Indoor Propagation Measurement, Simulation and Characterization

    Kazuhiko Tamesue, Seiji Nishi, San Hlaing Myint, Zheng Wen, Toshio Sato, Takuro Sato, Tetsuya Kawanishi

    2022 IEEE 9th International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, MAPE 2022     380 - 385  2022年

     概要を見る

    This paper presents radio propagation characteristics in a typical indoor space in a 300 GHz Sub-THz broadband channel. We clarified path loss and cross-polarization characteristics in multiple spaces using a linearly polarized horn antenna with 24.6 dBi (E-plane beamwidth 4.5°) and 8.7 dBi (E-plane beamwidth 35°) and a newly developed RHCP circularly polarized patch array antenna which has a gain of 3.4 dBi (E-plane beamwidth 10°) at 300 GHz. We also clarified the effect of shielding by the human body. Furthermore, a comprehensive analysis using ray tracing confirms the accurate agreement of the root mean square delay spread.

    DOI

    Scopus

  • Optimizing Packet Transmission for Ledger-Based Points Transfer System in LPWAN: Solutions, Evaluation and Standardization

    Xin Qi, Keping Yu, Toshio Sato, Kouichi Shibata, Eric Brigham, Takanori Tokutake, Rikiya Eguchi, Yusuke Maruyama, Zheng Wen, Kazuhiko Tamesue, Yutaka Katsuyama, Kazue Sako, Takuro Sato

    2021 ITU Kaleidoscope: Connecting Physical and Virtual Worlds (ITU K)    2021年12月

    DOI

  • Ledger-based Points Transfer System in LPWAN: From Disaster Management Aspect

    Xin Qi, Keping Yu, Toshio Sato, Kouichi Shibata, Eric Brigham, Takanori Tokutake, Rikiya Eguchi, Yusuke Maruyama, Zheng Wen, Kazuhiko Tamesue, Yutaka Katsuyama, Kazue Sako, Takuro Sato

    2021 International Conference on Information and Communication Technologies for Disaster Management (ICT-DM)    2021年12月

    DOI

  • Deep Learning Based Concealed Object Recognition in Active Millimeter Wave Imaging

    San Hlaing Myint, Yutaka Katsuyama, Toshio Sato, Xin Qi, Kazuhiko Tamesue, Zheng Wen, Keping Yu, Kiyohito Tokuda, Takuro Sato

    2021 IEEE Asia-Pacific Microwave Conference (APMC)    2021年11月

    DOI

  • Design and Implementation of 5G e-Health Systems: Technologies, Use Cases, and Future Challenges

    Di Zhang, Joel J. P. C. Rodrigues, Yunkai Zhai, Takuro Sato

    IEEE Communications Magazine   59 ( 9 ) 80 - 85  2021年09月

     概要を見る

    The fifth generation (5G) aims to connect massive amounts of devices with higher reliability, lower latency, and faster transmission speed, which are vital for implementing e-health systems. However, the current efforts on 5G e-health systems are still not enough to accomplish its full blueprint. In this article, we first discuss the related technologies from the physical layer, upper layer, and cross-layer perspectives on designing 5G e-health systems. We then elaborate two use cases according to our implementations (i.e., 5G e-health systems for remote health and 5G e-health systems for Covid-19 pandemic containment). We finally envision the future research trends and challenges of 5G e-health systems.

    DOI

    Scopus

    23
    被引用数
    (Scopus)
  • Content-oriented Multicamera Trajectory Forecasting Surveillance Network System

    Xin Qi, Toshio Sato, Keping Yu, San Hlaing Myint, Yutaka Katsuyama, Kazuhiko Tamesue, Kiyohito Tokuda, Zheng Wen, Takuro Sato

    2021 Twelfth International Conference on Ubiquitous and Future Networks (ICUFN)    2021年08月

    DOI

  • Position Estimation of Pedestrians in Surveillance Video Using Face Detection and Simple Camera Calibration

    Toshio Sato, Xin Qi, Keping Yu, Zheng Wen, Yutaka Katsuyama, Takuro Sato

    2021 17th International Conference on Machine Vision and Applications (MVA)    2021年07月

    DOI

  • Ledger-based Points Transfer System in LPWAN: From Disaster Management Aspect.

    Xin Qi 0002, Keping Yu, Toshio Sato, Kouichi Shibata, Eric Brigham, Takanori Tokutake, Rikiya Eguchi, Yusuke Maruyama, Zheng Wen, Kazuhiko Tamesue, Yutaka Katsuyama, Kazue Sako, Takuro Sato

    ICT-DM     150 - 155  2021年

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Secure Artificial Intelligence of Things for Implicit Group Recommendations

    Keping Yu, Zhiwei Guo, Yu Shen, Wei Wang, Jerry Chun Wei Lin, Takuro Sato

    IEEE Internet of Things Journal    2021年

     概要を見る

    The emergence of Artificial Intelligence of Things (AIoT) has provided novel insights for many social computing applications such as group recommender systems. As the distances between people have been greatly shortened, there has been more general demand for the provision of personalized services aimed at groups instead of individuals. The existing methods for capturing group-level preference features from individuals have mostly been established via aggregation and face two challenges: secure data management workflows are absent, and implicit preference feedback is ignored. To tackle these current difficulties, this paper proposes secure AIoT for implicit group recommendations (SAIoT-GR). For the hardware module, a secure IoT structure is developed as the bottom support platform. For the software module, a collaborative Bayesian network model and noncooperative game are introduced as algorithms. This secure AIoT architecture is able to maximize the advantages of the two modules. In addition, a large number of experiments are carried out to evaluate the performance of SAIoT-GR in terms of efficiency and robustness.

    DOI

    Scopus

    142
    被引用数
    (Scopus)
  • Congestion-Aware Suspicious Object Detection System Using Information-Centric Networking.

    Xin Qi 0002, Toshio Sato, Keping Yu, Zheng Wen, San Hlaing Myint, Yutaka Katsuyama, Kiyohito Tokuda, Takuro Sato

    18th IEEE Annual Consumer Communications & Networking Conference(CCNC)     1 - 6  2021年

    DOI

    Scopus

  • A Lightweight Ledger-Based Points Transfer System for Application-Oriented LPWAN

    Keping Yu, Kouichi Shibata, Takanori Tokutake, Rikiya Eguchi, Taiki Kondo, Yusuke Maruyama, Xin Qi, Zheng Wen, Toshio Sato, Yutaka Katsuyama, Kazue Sako, Takuro Sato

    2020 IEEE 6th International Conference on Computer and Communications, ICCC 2020     1972 - 1978  2020年12月

     概要を見る

    Along with the rapid development of IoT technology, Low power wide area network (LPWAN) has become the primary technology for IoT access today due to its characteristics of low cost, low power consumption, long-distance, and mass connections. At the same time, the points transfer system, as a typical third-party payment application, is attracting more and more extensive attention from academia and industry. Therefore, the research and development of a points transfer system for LPWAN are of great practical importance. However, the current points transfer systems often face problems such as centralization, high requirements on node computing power, and low robustness, which are difficult to adapt to the development of IoT. To address these problems, we propose a lightweight ledger-based points transfer system for application-oriented LPWAN. The system enables the points transfer between tags in LPWAN, where both tags and nodes are limited. Furthermore, it can be utilized even in disaster situations. Experimental results show that our proposed system is intensely robust and has a lower processing time than Bitcoin-like systems to cope with LPWAN's requirement.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • A geometry-based non-stationary wideband mimo channel model and correlation analysis for vehicular communication systems

    Suqin Pang, Fan Bai, Di Zhang, Zheng Wen, Takuro Sato

    Proceedings - 2020 16th International Conference on Mobility, Sensing and Networking, MSN 2020     496 - 501  2020年12月

     概要を見る

    In this paper, we propose a novel two-dimensional (2D) non-stationary geometry-based stochastic model (GBSM) for wideband multiple-input multiple-output (MIMO) base station-to-vehicle (B2V) channels. The proposed model combines one-ring and multiple ellipses with time-variant parameters, which can capture the channel non-stationary characteristics more precisely. The corresponding stochastic simulation model is then developed with finite number of effective scatterers. In addition, the birth-death process is applied to determine the number of ellipses in the proposed model at different time instants. Afterwards, the time-variant parameters and time-variant space cross-correlation functions (CCFs) are derived and analyzed. The impact of different parameters on the space CCFs such as vehicle traffic density (VTD) is investigated. Numerical results illustrate that the simulation model has great agreement with the reference model at different time instants, which indicates the correctness of our derivations.

    DOI

    Scopus

  • Radiometric Passive Imaging for Robust Concealed Object Identification

    San Hlaing Myint, Yutaka Katsuyama, Toshio Sato, Xin Qi, Zheng Wen, Keping Yu, Kiyohito Tokuda, Takuro Sato

    IEEE National Radar Conference - Proceedings   2020-September  2020年09月

     概要を見る

    Artificial Intelligence (AI) based millimeter wave radiometric imaging has become popular in a wide range of public security check systems, such as concealed object detection and identification. However, the low radiometric temperature contrast between small objects and low sensitivity is restricted to some extent. In this paper, an advanced radiometric passive imaging simulation model is proposed to improve the radiometric temperature contrast. This model considers additional noise, such as blur, variation in sensors, noise sources and summation of the number of frames. We establish a comprehensive training dataset that considers the physical characteristics of concealed objects. It can effectively fill the lack of a large database to avoid deteriorating the identification accuracy of AI applications. Moreover, it is also a key solution for improving the robustness of AI based object identification by using a convolutional neural network (CNN). Finally, simulation results are presented and analyzed to validate the proposed comprehensive training dataset and simulation model. Consequently, the proposed simulation model can effectively improve the robustness and accuracy of AI-based concealed object identification.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Simulation and Evaluation of 28GHz SHF Wave Beamforming with 4x4 Element Configuration Using RF Circuit Phase Control

    Kazuhiko Tamesue, Zheng Wen, Takuro Sato

    JOURNAL OF ADVANCED SIMULATION IN SCIENCE AND ENGINEERING   8 ( 1 ) 1 - 11  2020年

     概要を見る

    In the 5th generation mobile communication system (5G), there is a strong demand for higher speed and higher capacity. The beamforming technique using phased-array antennas is effective for long-distance radio propagation and for reducing interference signals in the high SHF (super high frequency) band because the phase shift of the antenna array elements can be controlled to produce a narrow-band beam and to control the directivity. We have developed the 28 GHz array antenna for small cells and evaluated the beamforming characteristics using an RF analog phase shifter control scheme. In this paper, we verify the computer simulation and evaluation results of the beamforming characteristics of a newly developed 4x4 phased array antenna.

    DOI

  • Pedestrian Positioning in Surveillance Video using Anthropometric Properties for Effective Communication.

    Toshio Sato, Xin Qi 0002, Keping Yu, Zheng Wen, San Hlaing Myint, Yutaka Katsuyama, Kiyohito Tokuda, Takuro Sato

    23rd International Symposium on Wireless Personal Multimedia Communications(WPMC)     1 - 6  2020年

    DOI

    Scopus

    3
    被引用数
    (Scopus)
  • Blockchain-based Content-oriented Surveillance Network.

    Xin Qi 0002, Keping Yu, Zheng Wen, San Hlaing Myint, Yutaka Katsuyama, Toshio Sato, Kiyohito Tokuda, Takuro Sato

    91st IEEE Vehicular Technology Conference     1 - 6  2020年

    DOI

    Scopus

    5
    被引用数
    (Scopus)
  • Blockchain-Empowered Contact Tracing for COVID-19 Using Crypto-Spatiotemporal Information.

    Zheng Wen, Keping Yu, Xin Qi 0002, Toshio Sato, Yutaka Katsuyama, Takuro Sato, Wataru Kameyama, Fumiyuki Kato, Yang Cao 0011, Masatoshi Yoshikawa, Min Luo, Jun Hashimoto

    22nd IEEE International Conference on E-health Networking(HealthCom)     1 - 6  2020年

    DOI

    Scopus

    5
    被引用数
    (Scopus)
  • Radiometric Passive Imaging for Robust Concealed Object Identification

    San Hlaing Myint, Yutaka Katsuyama, Toshio Sato, Xin Qi, Zheng Wen, Keping Yu, Kiyohito Tokuda, Takuro Sato

    2020 IEEE RADAR CONFERENCE (RADARCONF20)    2020年

     概要を見る

    Artificial Intelligence (AI) based millimeter wave radiometric imaging has become popular in a wide range of public security check systems, such as concealed object detection and identification. However, the low radiometric temperature contrast between small objects and low sensitivity is restricted to some extent. In this paper, an advanced radiometric passive imaging simulation model is proposed to improve the radiometric temperature contrast. This model considers additional noise, such as blur, variation in sensors, noise sources and summation of the number of frames. We establish a comprehensive training dataset that considers the physical characteristics of concealed objects. It can effectively fill the lack of a large database to avoid deteriorating the identification accuracy of AI applications. Moreover, it is also a key solution for improving the robustness of AI based object identification by using a convolutional neural network (CNN). Finally, simulation results are presented and analyzed to validate the proposed comprehensive training dataset and simulation model. Consequently, the proposed simulation model can effectively improve the robustness and accuracy of AI-based concealed object identification.

  • Design and Performance Evaluation of an AI-Based W-Band Suspicious Object Detection System for Moving Persons in the IoT Paradigm

    Keping Yu, Xin Qi, Toshio Sato, San Hlaing Myint, Zheng Wen, Yutaka Katsuyama, Kiyohito Tokuda, Wataru Kameyama, Takuro Sato

    IEEE Access   8   81378 - 81393  2020年

    DOI

  • Adaptive Caching for Beneficial Content Distribution in Information-Centric Networking.

    Quang Ngoc Nguyen, Jairo E. Lopez, Toshitaka Tsuda, Takuro Sato, Kien Nguyen, Mohammad Arifuzzaman, Cutifa Safitri, Nguyen Huu Thanh 0001

    2020 International Conference on Information Networking(ICOIN)     535 - 540  2020年  [査読有り]

    DOI

    Scopus

    11
    被引用数
    (Scopus)
  • 5G-Enabled Health Systems: Solutions, Challenges and Future Research Trends

    Di Zhang, Teng Zhang, Yunkai Zhai, Joel J.P.C. Rodrigues, Dalong Zhang, Zheng Wen, Keping Yu, Takuro Sato

    11th Academic Conference ITU Kaleidoscope: ICT for Health: Networks, Standards and Innovation, ITU K 2019    2019年12月

     概要を見る

    In the literature, Information communication technology (ICT)-assisted health systems have been intensively discussed. However, it has seldom become a reality. This is mainly due to the current wireless technologies' limited transmission rate, few connected devices and high latency. On the contrary, the fifth generation (5G) wireless communications can connect more devices, provide faster transmission rates and a lower latency. In this article, we first introduce the 5G-enabled health systems and our specific implementation in the first affiliated hospital of Zhengzhou University (FAHZZU). Afterwards, the potential challenges and future research trends on demonstrating the 5G-enabled health systems are discussed.

    DOI

    Scopus

    11
    被引用数
    (Scopus)
  • Detour Path Angular Information based Range Free Localization with Last Hop RSSI Measurement based Distance Calculation

    Anup Kumar Paul, Mohammad Arifuzzaman, Keping Yu, Takuro Sato

    2019 12th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2019    2019年11月

     概要を見る

    The location estimation accuracy of range-free localization (RFL) is a crucial issue in Wireless Sensor Networks (WSNs). The accuracy has significant impact on localization dependent routing protocols and applications. The assumption that the sensor nodes are deployed in regular areas without any obstacles do not match the practical deployment scenarios, especially for scenarios like outdoor deployment of WSNs. In this paper, we propose a hybrid solution by combining a RFL method and range-based localization (RBL) method namely Received Signal Strength Indication (RSSI) to tackle the detoured path between sensors in anisotropic network and to combat the last hop distance calculation problem respectively. As a result, our hybrid approach significantly improves the localization accuracy in anisotropic network as compared to range free method only. We calculate the average hop distance (AHD) of detoured path by estimating the angle of the middle of the transmission path between every two anchor pairs one by one. The AHD is finally adjusted by estimating the RSSI based last hop distance measurement. Based on the simulation results, it is observed that our hybrid approach with few anchor nodes outperforms other RFL algorithms in anisotropic network and indicates an improvement in the localization accuracy.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • Content-Oriented Common IoT Platform for Emergency Management Scenarios

    Zheng Wen, Xin Qi, Keping Yu, Jairo Eduardo Lopez, Takuro Sato

    International Symposium on Wireless Personal Multimedia Communications, WPMC   2019-November  2019年11月

     概要を見る

    With the explosive growth of Internet of Things (IoT) devices, the demand for network systems is increasing rapidly. In terms of bandwidth, security, management, and more, there are many bottlenecks in current network systems. To address the above issues, future network technology, such as information-centric networking, is proposed to provide a good solution for IoT applications. However, new communications technologies need to be implemented with new communications applications. The traditional client/server-based network applications will become one of the bottlenecks in information-centric networking (ICN). In this paper, the work of the Ministry of Internal Affairs and Communications project at Waseda University over the past three years is summarized, and a highly efficient content-oriented common IoT platform for emergency management scenarios is proposed.

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • Modeling and Analysis of Error Process in 5G Wireless Communication Using Two-State Markov Chain

    San Hlaing Myint, Keping Yu, Takuro Sato

    IEEE Access   7   26391 - 26401  2019年

     概要を見る

    In fifth-generation wireless communications, data transmission is challenging due to the occurrence of burst errors and packet losses that are caused by multipath fading in multipath transmissions. To acquire more efficient and reliable data transmissions and to mitigate the transmission medium degradation in the 5G networks, it is important to study the error patterns or burst the error sequences that can provide insights into the behavior of 5G wireless data transmissions. In this paper, a two-state Markov-based 5G error model is investigated and developed to model the statistical characteristics of the underlying error process in the 5G network. The underlying 5G error process was obtained from our 5G wireless simulation, which was implemented based on three different kinds of modulation methods, including QPSK, 16QAM, and 64QAM, and was employed using the LDPC and TURBO coding methods. By comparing the burst or gap error statistics of the reference error sequences from the 5G wireless simulations and those of the generated error sequences from the two-state Markov error model, we show that the error behaviors of the coded OFDM 5G simulations can be adequately modeled by using the two-state Markov error model. Our proposed two-state Markov-based wireless error model can help to provide a more thorough understanding of the error process in 5G wireless communications and to evaluate the error control strategies with less computational complexity and shorter simulation times.

    DOI

    Scopus

    18
    被引用数
    (Scopus)
  • Information-Centric Networking: Research and Standardization Status

    Keping Yu, Suyong Eum, Toshihiko Kurita, Qiaozhi Hua, Takuro Sato, Hidenori Nakazato, Tohru Asami, Ved P. Kafle

    IEEE Access   7   126164 - 126176  2019年

     概要を見る

    Information-centric networking (ICN) is a new approach to networking contents rather than devices that hold the contents. It has recently attracted much attention of network research and standardization communities. National and multi-national funded research projects have progressed worldwide. International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) started ICN standardization activities in 2012. In parallel, the standards-oriented research cooperation is progressing in the Information-Centric Networking Research Group (ICNRG) of the Internet Research Task Force (IRTF). All these global efforts have been collectively advancing the novel network architecture of ICN. However, there are very few surveys and discussions on the detailed ICN standardization status. To update the reader with information about the ICN research and standardization related activities, this paper starts with the history of global activities on ICN from 2010, giving references to various projects. It then describes the recent progress in the standardization of ICN component technologies in ITU-T and various documents produced by ICNRG. Lastly, it discusses the future directions for progressing ICN.

    DOI

    Scopus

    47
    被引用数
    (Scopus)
  • Design and Implementation of Integrated ICN and CDN as a Video Streaming Service.

    Chengkai Yan,Array, Ilias Benkacem, Daisuke Okabe, Akihiro Nakao, Toshitaka Tsuda, Cutifa Safitri, Tarik Taleb, Takuro Sato

    Wired/Wireless Internet Communications - 17th IFIP WG 6.2 International Conference, WWIC 2019, Bologna, Italy, June 17-18, 2019, Proceedings     194 - 206  2019年  [査読有り]

    DOI

    Scopus

    8
    被引用数
    (Scopus)
  • An intelligent content prefix classification approach for quality of service optimization in information-centric networking

    Cutifa Safitri, Yoshihide Yamada, Sabariah Baharun, Shidrokh Goudarzi, Quang Ngoc Nguyen, Keping Yu, Takuro Sato

    Future Internet   10 ( 4 )  2018年04月

     概要を見る

    This research proposes an intelligent classification framework for quality of service (QoS) performance improvement in information-centric networking (ICN). The proposal works towards keyword classification techniques to obtain the most valuable information via suitable content prefixes in ICN. In this study, we have achieved the intelligent function using Artificial Intelligence (AI) implementation. Particularly, to find the most suitable and promising intelligent approach for maintaining QoS matrices, we have evaluated various AI algorithms, including evolutionary algorithms (EA), swarm intelligence (SI), and machine learning (ML) by using the cost function to assess their classification performances. With the goal of enabling a complete ICN prefix classification solution, we also propose a hybrid implementation to optimize classification performances by integration of relevant AI algorithms. This hybrid mechanism searches for a final minimum structure to prevent the local optima from happening. By simulation, the evaluation results show that the proposal outperforms EA and ML in terms of network resource utilization and response delay for QoS performance optimization.

    DOI

    Scopus

    9
    被引用数
    (Scopus)
  • A Context-Aware Green Information-Centric Networking Model for Future Wireless Communications

    Quang Ngoc Nguyen, Mohammad Arifuzzaman, Keping Yu, Takuro Sato

    IEEE Access   6   22804 - 22816  2018年04月

     概要を見る

    This research proposes a novel wireless information-centric networking (ICN) architecture, namely, Context-Aware Green ICN Model (CAGIM), which can adapt the power consumption of network nodes to optimized values according to the associated link utilization. The power adaption in ICN nodes is conducted through dynamically adjusting the link-rate corresponding to content popularity and traffic load to reduce wasteful energy consumption. Moreover, we propose a smart popularity-based caching strategy, called distinguished caching scheme (DCS), with the introduction of hot and cold-caching partitions of ICN node's cache storage for popular and non-popular content objects, respectively. DCS improves the content diversity of the cache storage by adjusting, for each content, the number of chunks to be cached at ICN nodes based on its type and popularity level. DCS thus can further decrease the network system power consumption, thanks to its improved cache hit that reduces network traffic load. Toward the goal of realizing a context-aware green wireless network system with efficient content delivery, we also design a Wi-Fi Direct based scheme as an alternative approach to minimize power consumption and latency by sharing essential/important content objects via direct communications with power-saving mechanisms in the case that wireless local area network connections are not available. The evaluation results show that CAGIM can improve network efficiency by reducing both hop-count and power consumption considerably compared with existing wireless network systems with different well-known caching schemes. This proposal enables a flexible and efficient content delivery mechanism for future networks with various real-life scenarios, like Green building, Green company, and Green campus content accesses.

    DOI

    Scopus

    32
    被引用数
    (Scopus)
  • Video streaming based on ICN

    Chengkai Yan

    電子情報情報通信学会 総合大会    2018年03月  [査読有り]

  • A New Implementation of Data Transmission over ICN

    RONG TAI

    電子情報通信学会 総合大会    2018年03月

  • An Intelligent Real-Time Surveillance System Based on ICN

    DU YINGSHUANG

    電子情報通信学会 総合大会    2018年03月

  • Analysis of CPolSK-based FSO system working in space-to-ground channel

    Yuwei Su, Takuro Sato

    Optics Communications   410   660 - 667  2018年03月  [査読有り]

     概要を見る

    In this article, the transmission performance of a circle polarization shift keying (CPolSK)-based free space optical (FSO) system working in space-to-ground channel is analyzed. Formulas describing the optical polarization distortion caused by the atmospheric turbulence and the communication qualities in terms of signal-to-noise-ratio (SNR), bit-error-ratio (BER) and outage probability of the proposed system are derived. Based on the Stokes parameters data measured by a Japanese optical communication satellite, we evaluate the space-to-ground FSO link and simulate the system performance under a varying regime of turbulence strength. The proposed system provides a more efficient way to compensate scintillation effects in a comparison with the on-off-keying (OOK)-based FSO system. These results are useful to the designing and evaluating of a deep space FSO communication system.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Utilization efficient game-theoretical handover scheme for Macro-Femtocell networks

    Qiaozhi Hua, Yuwei Su, Takuro Sato, Keping Yu

    International Symposium on Wireless Personal Multimedia Communications, WPMC   2017-December   57 - 62  2018年02月

     概要を見る

    The Macro-Femtocell system is widely used in current society because the cooperation between Macrocell base stations and Femtocell base stations can improve the communication capacity of certain areas and adapt to the large multi-user demand. To increase the system's communication quality, the handover scheme should be utilized when the user is moving within the limited coverage of Femtocell base stations. Generally, the Markov decision strategy is used for mobile users in the process of handover. However, the Markov decision process can't ensure the maximum utilization balance of Macrocell base stations and Femtocell base stations. In this case, users often choose the base station offering the highest signal strength, which will cause a Macrocell base station's load to be too large and Femtocell base stations to be idle, so the system's utilization is very low. To address this problem, we propose the utilization efficient game-theoretical handover scheme based on Starckberg competition theory for appropriately increasing a Femtocell base station's transmitting power. This can ensure the communication quality of the system and guarantees the system's load balance to induce users to take the initiative in processing the handover scheme. Finally, the simulation results show that our strategy is effective in choosing the best base station to receive the highest signal strength by predicting the user's movement. It could also realize the load balance of the antenna in the system. The overall transmission quality of the user group is optimized.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Naming Scheme Using NLP Machine Learning Method for Network Weather Monitoring System Based on ICN

    Toru Mochida, Takuro Sato

    International Symposium on Wireless Personal Multimedia Communications    2017年12月  [査読有り]

  • An Artificial Neural Network-Based Distributed Information-Centric Network Service

    Zheng Wen, Takuro Sato

    International Symposium on Wireless Personal Multimedia Communications    2017年12月  [査読有り]

  • Performance Analysis of Non-Regenerative Massive-MIMO-NOMA Relay Systems for 5G

    Di Zhang, Yuanwei Liu, Zhiguo Ding, Zhenyu Zhou, Arumugam Nallanathan, Takuro Sato

    IEEE TRANSACTIONS ON COMMUNICATIONS   65 ( 11 ) 4777 - 4790  2017年11月  [査読有り]

     概要を見る

    The non-regenerative massive multi-input-multi-output (MIMO) non-orthogonal multiple access (NOMA) relay systems are introduced in this paper. The NOMA is invoked with a superposition coding technique at the transmitter and successive interference cancellation (SIC) technique at the receiver. In addition, a maximum mean square error-SIC receiver design is adopted. With the aid of deterministic equivalent and matrix analysis tools, a closed-form expression of the signal to interference plus noise ratio (SINR) is derived. To characterize the performance of the considered systems, closed-form expressions of the capacity and sum rate are further obtained based on the derived SINR expression. Insights from the derived analytical results demonstrate that the ratio between the transmitter antenna number and the relay number is a dominate factor of the system performance. Afterward, the correctness of the derived expressions are verified by the Monte Carlo simulations with numerical results. Simulation results also illustrate that: 1) the transmitter antenna, averaged power value, and user number display the positive correlations on the capacity and sum rate performances, whereas the relay number displays a negative correlation on the performance and 2) the combined massive-MIMO-NOMA scheme is capable of achieving higher capacity performance compared with the conventional MIMO-NOMA, relay-assisted NOMA, and massive-MIMO orthogonal multiple access (OMA) scheme.

    DOI

    Scopus

    84
    被引用数
    (Scopus)
  • Localization in wireless sensor networks: A survey on algorithms, measurement techniques, applications and challenges

    Anup Kumar Paul, Takuro Sato

    Journal of Sensor and Actuator Networks   6 ( 4 )  2017年10月

     概要を見る

    Localization is an important aspect in the field of wireless sensor networks (WSNs) that has developed significant research interest among academia and research community. Wireless sensor network is formed by a large number of tiny, low energy, limited processing capability and low-cost sensors that communicate with each other in ad-hoc fashion. The task of determining physical coordinates of sensor nodes in WSNs is known as localization or positioning and is a key factor in today’s communication systems to estimate the place of origin of events. As the requirement of the positioning accuracy for different applications varies, different localization methods are used in different applications and there are several challenges in some special scenarios such as forest fire detection. In this paper, we survey different measurement techniques and strategies for range based and range free localization with an emphasis on the latter. Further, we discuss different localization-based applications, where the estimation of the location information is crucial. Finally, a comprehensive discussion of the challenges such as accuracy, cost, complexity, and scalability are given.

    DOI

    Scopus

    199
    被引用数
    (Scopus)
  • Toward Standardization Activities for Future Networks in ITU-T: A Viewpoint from Y.Suppl.35: ITU-T Y.3033 Data-aware Networking-Scenarios and Use Cases

    Keping Yu, Takuro Sato

    IEEE International Conference on Computer and Communications (ICCC)    2017年10月

  • Standardization Activities for Future Networks in ITU-T: A Case Study from Y.3071: Data Aware Networking (Information Centric Networking) – Requirements and Capabilities

    Keping Yu, Takuro Sato

    IEEE International Conference on Computer and Communications (ICCC)    2017年10月

  • Congestion Control in Information-Centric Networking utilizing Content Popularity-based Delay Time

    Rungrot Sukjaimuk

    The 36th JSST Annual International Conference on Simulation Technology    2017年10月  [査読有り]

  • Seamless mobility in ICN for mobile consumers with mobile producers

    Jairo López, Takuro Sato

    IEICE Transactions on Communications   E100B ( 10 ) 1827 - 1836  2017年10月

     概要を見る

    In order to support seamless mobility in the Information- Centric Networking (ICN) Architecture we propose the Named-Node Network Architecture (3NA). 3NA introduces two independent namespaces to ICN, the 3N namespace used to uniquely identify nodes within a network and the Point of Attachment (PoA) namespace to identify a node's PoA to the network. The mappings between the two namespaces, along with all the necessary mechanisms to keep the mappings updated over time, are used when routing ICN packets to improve delay and the goodput when either the producer or the consumer are mobile. To support simultaneous producer and consumer mobility, we expand on the 3NA by adding a new Protocol Data Unit (PDU), the DU PDU. The DU PDU permits the encapsulation of ICN packets in a header that has source and destination name fields which belong to 3NA's 3N namespace. The new PDU permits seamless connectivity as long as 3NA's point of attachment signaling is strictly followed. We demonstrate the performance of the DU PDU against our previous defined communication methods and Named Data Networking's (NDN) Smart Flooding forwarding strategy using our open source nnnSIM module for the ns-3 framework. The new PDU outperforms all existing alternatives when the producer or both consumer and provider are mobile, obtaining overall lower mean network delay and higher median goodput.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • Capacity Analysis of NOMA With mmWave Massive MIMO Systems

    Di Zhang, Zhenyu Zhou, Chen Xu, Yan Zhang, Jonathan Rodriguez, Takuro Sato

    IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS   35 ( 7 ) 1606 - 1618  2017年07月  [査読有り]

     概要を見る

    Non-orthogonal multiple access (NOMA), millimeter wave (mmWave), and massive multiple-input-multiple-output (MIMO) have been emerging as key technologies for fifth generation mobile communications. However, less studies have been done on combining the three technologies into the converged systems. In addition, how many capacity improvements can be achieved via this combination remains unclear. In this paper, we provide an in-depth capacity analysis for the integrated NOMA-mmWave-massive-MIMO systems. First, a simplified mmWave channel model is introduced by extending the uniform random single-path model with angle of arrival. Afterward, we divide the capacity analysis into the low signal to noise ratio (SNR) and high-SNR regimes based on the dominant factors of signal to interference plus noise ratio. In the noise-dominated low-SNR regime, the capacity analysis is derived by the deterministic equivalent method with the Stieltjes-Shannon transform. In contrast, the statistic and eigenvalue distribution tools are invoked for the capacity analysis in the interference-dominated high-SNR regime. The exact capacity expression and the low-complexity asymptotic capacity expression are derived based on the probability distribution function of the channel eigenvalue. Finally, simulation results validate the theoretical analysis and demonstrate that significant capacity improvements can be achieved by the integrated NOMA-mmWave-massive-MIMO systems.

    DOI

    Scopus

    129
    被引用数
    (Scopus)
  • A key technology for standardizing outdoor optical wireless communications

    Yuwei Su, Takuro Sato

    ICT Express   3 ( 2 ) 62 - 66  2017年06月

     概要を見る

    In this paper, we introduce a key technology, polarization modulation (PM), which should be taken into account when standardizing outdoor optical wireless communications (OWC), also known as free-space optical communications (FSO). We analyze the distortion of the polarization state when a laser beam propagates through the atmospheric channel. The floating range of the optical polarization was estimated and the necessity of researching the proposed technology was discussed. Moreover, we conducted a comparison between the PM-based FSO system and intensity modulation-based FSO system. The conclusions will be helpful in establishing the FSO standard architectures.

    DOI

    Scopus

    7
    被引用数
    (Scopus)
  • Node Name Routing in Information-Centric Ad-Hoc Network

    Zheng Wen, Di Zhang, Keping Yu, Takuro Sato

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E100A ( 2 ) 680 - 687  2017年02月  [査読有り]

     概要を見る

    We propose the node name routing (NNR) strategy for information-centric ad-hoc networks based on the named-node networking (3N). This strategy is especially valuable for use in disaster areas because, when the Internet is out of service during a disaster, our strategy can be used to set up a self-organizing network via cell phones or other terminal devices that have a sharing ability, and it does not rely on a base station (BS) or similar providers. Our proposed strategy can solve the multiple-name problem that has arisen in prior 3N proposals, as well as the dead loop problems in both 3N ad-hoc networks and TCP/IP ad-hoc networks. To evaluate the NNR strategy, it is compared with the optimized link state routing protocol (OLSR) and the dynamic source routing (DSR) strategy. Computer-based comprehensive simulations showed that our NNR proposal exhibits a better performance in this environment when all of the users are moving randomly. We further observed that with a growing number of users, our NNR protocol performs better in terms of packet delivery, routing cost, etc.

    DOI CiNii

    Scopus

    4
    被引用数
    (Scopus)
  • Node name routing in information-centric Ad-Hoc network

    Wen, Zheng, Zhang, Di, Yu, Keping, Sato, Takuro, Sato, Takuro

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences   E100A ( 2 ) 680 - 687  2017年02月

     概要を見る

    © 2017 The Institute of Electronics, Information and Communication Engineers. We propose the node name routing (NNR) strategy for information-centric ad-hoc networks based on the named-node networking (3N). This strategy is especially valuable for use in disaster areas because, when the Internet is out of service during a disaster, our strategy can be used to set up a self-organizing network via cell phones or other terminal devices that have a sharing ability, and it does not rely on a base station (BS) or similar providers. Our proposed strategy can solve the multiple-name problem that has arisen in prior 3N proposals, as well as the dead loop problems in both 3N ad-hoc networks and TCP/IP ad-hoc networks. To evaluate the NNR strategy, it is compared with the optimized link state routing protocol (OLSR) and the dynamic source routing (DSR) strategy. Computer-based comprehensive simulations showed that our NNR proposal exhibits a better performance in this environment when all of the users are moving randomly. We further observed that with a growing number of users, our NNR protocol performs better in terms of packet delivery, routing cost, etc.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • Seamless Mobility in ICN for Mobile Consumers with Mobile Producers

    LÓPEZ Jairo, SATO Takuro

    IEICE Transactions on Communications   100 ( 10 ) 1827 - 1836  2017年

     概要を見る

    <p>In order to support seamless mobility in the Information-Centric Networking (ICN) Architecture we propose the Named-Node Network Architecture (3NA). 3NA introduces two independent namespaces to ICN, the 3N namespace used to uniquely identify nodes within a network and the Point of Attachment (PoA) namespace to identify a node's PoA to the network. The mappings between the two namespaces, along with all the necessary mechanisms to keep the mappings updated over time, are used when routing ICN packets to improve delay and the goodput when either the producer or the consumer are mobile. To support simultaneous producer and consumer mobility, we expand on the 3NA by adding a new Protocol Data Unit (PDU), the DU PDU. The DU PDU permits the encapsulation of ICN packets in a header that has source and destination name fields which belong to 3NA's 3N namespace. The new PDU permits seamless connectivity as long as 3NA's point of attachment signaling is strictly followed. We demonstrate the performance of the DU PDU against our previous defined communication methods and Named Data Networking's (NDN) Smart Flooding forwarding strategy using our open source nnnSIM module for the ns-3 framework. The new PDU outperforms all existing alternatives when the producer or both consumer and provider are mobile, obtaining overall lower mean network delay and higher median goodput.</p>

    DOI CiNii

    Scopus

    4
    被引用数
    (Scopus)
  • SEAMLESS MOBILITY IN ICN FOR MOBILE CONSUMERS WITH MOBILE PRODUCERS

    LÓPEZ Jairo, SATO Takuro

    IEICE Transactions on Communications   100 ( 10 ) 1827 - 1836  2017年

     概要を見る

    <p>In order to support seamless mobility in the Information-Centric Networking (ICN) Architecture we propose the Named-Node Network Architecture (3NA). 3NA introduces two independent namespaces to ICN, the 3N namespace used to uniquely identify nodes within a network and the Point of Attachment (PoA) namespace to identify a node's PoA to the network. The mappings between the two namespaces, along with all the necessary mechanisms to keep the mappings updated over time, are used when routing ICN packets to improve delay and the goodput when either the producer or the consumer are mobile.</p><p> To support simultaneous producer and consumer mobility, we expand on the 3NA by adding a new Protocol Data Unit (PDU), the DU PDU. The DU PDU permits the encapsulation of ICN packets in a header that has source and destination name fields which belong to 3NA's 3N namespace. The new PDU permits seamless connectivity as long as 3NA's point of attachment signaling is strictly followed. We demonstrate the performance of the DU PDU against our previous defined communication methods and Named Data Networking's (NDN) Smart Flooding forwarding strategy using our open source nnnSIM module for the ns-3 framework. The new PDU outperforms all existing alternatives when the producer or both consumer and provider are mobile, obtaining overall lower mean network delay and higher median goodput.</p>

    DOI CiNii

    Scopus

    4
    被引用数
    (Scopus)
  • A Game-Theoretical Green Networking Approach for Information-Centric Networks

    Quang. N. Nguyen, Keping Yu, Takuro Sato, Mohammad Arifuzzaman

    2017 IEEE CONFERENCE ON STANDARDS FOR COMMUNICATIONS AND NETWORKING (CSCN)     132 - 137  2017年  [査読有り]

     概要を見る

    In order to address the energy issue and enhance the feasibility of Information-Centric Networking (ICN) in the case of access networks, this research proposes a novel Green ICN design which can adapt power consumption of network devices to their optimized real-time link-utilizations based on content popularity levels. We utilize dynamic ALR (Adaptive Link Rate) based scheme for content nodes to provide efficient content delivery as a realistic approach for the economically viable green network. We also develop a game-theoretical model to study the interaction between an ISP and a network equipment company in the context of green networking. Specifically, we present the system concept and some demonstration results of game-based Green ICN model to analyze the economic incentives of players. Moreover, we discuss ICN deployment and standardization challenges, then show that the proposal is robust, easy to deploy and practically relevant for the network players.

    DOI

    Scopus

    13
    被引用数
    (Scopus)
  • Integrating energy efficiency analysis of massive MIMO-based C-RAN

    Di Zhang, Muhammad Tariq, Shahid Mumtaz, Jonathan Rodriguez, Takuro Sato

    EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING    2016年12月  [査読有り]

     概要を見る

    Besides the prior study of energy efficiency (EE) that focuses on single component (antenna, radio frequency (RF) chain, circuit, etc.), or limited to one base station (BS) area, in this paper, EE is integrated, investigated with various components (antenna, RF chain, circuit, coverage area) considering in, based on an optimized system model. That is, one optimized multi-BS system model is introduced beforehand with the cloud radio access network (C-RAN) for easier deployment of the selecting/sleeping mechanism. In addition, the system EE is described by an optimization problem while taking more component factors into consideration. While solving, this integrated optimization problem in all time intervals of all BS areas is proved to be equal to an optimization problem of each single BS area within each single time interval. After that, the integrated optimization solution is obtained while adding up the single-BS-single-interval optimization solutions, whereas the later solution is addressed by an offline decision method plus a convex optimization strategy. Observation from the numerical results demonstrates that the antenna power consumption is the dominant factor of the power consumption, which therefore, the dominant factor of EE performance.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Integrating energy efficiency analysis of massive MIMO-based C-RAN

    Di Zhang, Muhammad Tariq, Shahid Mumtaz, Jonathan Rodriguez, Takuro Sato

    Eurasip Journal on Wireless Communications and Networking   2016 ( 1 )  2016年12月

     概要を見る

    Besides the prior study of energy efficiency (EE) that focuses on single component (antenna, radio frequency (RF) chain, circuit, etc.), or limited to one base station (BS) area, in this paper, EE is integrated, investigated with various components (antenna, RF chain, circuit, coverage area) considering in, based on an optimized system model. That is, one optimized multi-BS system model is introduced beforehand with the cloud radio access network (C-RAN) for easier deployment of the selecting/sleeping mechanism. In addition, the system EE is described by an optimization problem while taking more component factors into consideration. While solving, this integrated optimization problem in all time intervals of all BS areas is proved to be equal to an optimization problem of each single BS area within each single time interval. After that, the integrated optimization solution is obtained while adding up the single-BS-single-interval optimization solutions, whereas the later solution is addressed by an offline decision method plus a convex optimization strategy. Observation from the numerical results demonstrates that the antenna power consumption is the dominant factor of the power consumption, which therefore, the dominant factor of EE performance.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • One Integrated Energy Efficiency Proposal for 5G IoT Communications

    Di Zhang, Zhenyu Zhou, Shahid Mumtaz, Jonathan Rodriguez, Takuro Sato

    IEEE INTERNET OF THINGS JOURNAL   3 ( 6 ) 1346 - 1354  2016年12月  [査読有り]

     概要を見る

    To further enhance the energy efficiency (EE) performance of fifth generation (5G) Internet of Things systems, an integrated structure is proposed in this paper. That is, other than prior studies that separately study the wireless and wired parts, the wireless and wired parts are holistically combined together to comprehensively optimize the EE of the whole system. The integrated system structure is introduced beforehand with the proposed unified control center components for better deployment of the select-and-sleep mechanism. In addition, in the wireless part, one cellular partition zooming (CPZ) mechanism is proposed. In contrast, in the wired part, a precaching mechanism is introduced. With these proposals, the proposed system EE performance is investigated. Comprehensive computer-based simulation results demonstrate that the proposed schemes display better EE performance. This is due to the fact that system power consumption is further reduced with these schemes as compared to the prior work.

    DOI

    Scopus

    99
    被引用数
    (Scopus)
  • Proactive Content Caching for Mobile Video Utilizing Transportation Systems and Evaluation Through Field Experiments

    Kenji Kanai, Takeshi Muto, Jiro Katto, Shinya Yamamura, Tomoyuki Furutono, Takafumi Saito, Hirohide Mikami, Kaoru Kusachi, Toshitaka Tsuda, Wataru Kameyama, Yong-Jin Park, Takuro Sato

    IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS   34 ( 8 ) 2102 - 2114  2016年08月  [査読有り]

     概要を見る

    In order to provide high-quality and highly reliable video delivery services for mobile users, especially train passengers, we propose a proactive content caching scheme that uses transportation systems. In our system, we place content servers with cache capability [e.g., content centric networking/named data networking (CCN/NDN)] in every train and station. Video segments encapsulated by MPEG-Dynamic Adaptive Streaming over HTTP (MPEG-DASH) are distributed and pre-cached by the station servers before the trains arrive at the stations. The trains receive content via high-speed wireless transport, such as wireless LANs or millimeter waves, when they stop at the stations. We developed prototype systems based on hypertext transfer protocol and CCN/NDN protocol, evaluate their performance through two field experiments that uses actual trains, and compare with traditional video streaming over cellular networks. Such evaluations indicate that our system can achieve high-quality video delivery without interruption for up to 50 users simultaneously.

    DOI

    Scopus

    40
    被引用数
    (Scopus)
  • A Novel Energy Efficient Object Detection and Image Transmission Approach for Wireless Multimedia Sensor Networks

    Yasar Abbas Ur Rehman, Muhammad Tariq, Takuro Sato

    IEEE SENSORS JOURNAL   16 ( 15 ) 5942 - 5949  2016年08月  [査読有り]

     概要を見る

    Energy efficient object detection and image transmission are one of the key issues in wireless multimedia sensor networks (WMSN). Recent approaches in the WMSN propose in-node object detection and tracking algorithms. However, a little effort has been made to effectively detect object presence and absence in images in the WMSN. Since object detection has a direct relation with image transmission, therefore effective object detection algorithm would provide a reduction in the false transmission of image information. In this paper, a novel object presence model and an image transmission scheme are proposed for the WMSN. This scheme uses the transmission of image segments rather than a complete image. It guarantees in-node energy conservation and minimal image content transmission to the sink node. The proposed scheme is evaluated based on in-node energy consumption and reconstructed image peak signal-to-noise ratio (PSNR). Simulation results show that the proposed approach saves 95% of the node energy with the received image PSNR of 46 dB as compared with other state-of-the- art approaches.

    DOI

    Scopus

    57
    被引用数
    (Scopus)
  • Transmission analysis of CPo1M-based OFDM FSO system in atmospheric turbulence

    Yuwei Su, Fan Bai, Takuro Sato

    OPTICS COMMUNICATIONS   369   111 - 119  2016年06月  [査読有り]

     概要を見る

    In this paper, we propose to implement a consecutive polarization modulation (CPolM) scheme to transmit orthogonal frequency division multiplexing (OFDM) signal over the turbulent free-space optical (FSO) links. We analyze the fluctuation of polarization states of an optical wave while propagating through the turbulence channel of which the refractive-index property is described by Kolmogorov spectrum. The transmission performance in terms of signal-to-noise-ratio (SNR), symbol-error-ratio (SER) and outage probability of the proposed system are evaluated. The proposed system provides a more efficient way to compensate scintillation effects in a comparison with the intensity modulation (IM) based OFDM FSO system under a varying degrees of turbulence strength regimes. (C) 2016 Elsevier B.V. All rights reserved.

    DOI

    Scopus

    9
    被引用数
    (Scopus)
  • BS-3-7 Analysis of Transmission Efficiency Based on Social Big Data(BS-3. Advanced Networking Technologies for Innovative Information Networks)

    Hua Qiaozhi, Zhang Di, Qi Xin, Sato Takuro

    電子情報通信学会総合大会講演論文集   2016 ( 2 ) "S - 25"-"S-26"  2016年03月

     概要を見る

    The information revolution process is boosting the development of social big data. Other than the use of traditional sampling of statistical methods to analysis data, people nowadays shifts to use the real-time data. And the transmission of massive data puts forward new demands. Here in this paper, to cater this trend, with the proposed new way of packets transmission management with Information-Centric Network (ICN), the transmission is compared with traditional IP based transmission, which simulation results demonstrated that both the network transmission speed and efficiency improved significantly by our method.

    CiNii

  • BS-3-6 Energy Efficient Data Downloading Scheme for C-RAN(BS-3. Advanced Networking Technologies for Innovative Information Networks)

    Win Zin Ko Ko, ZHANG Di, SATO Takuro

    電子情報通信学会総合大会講演論文集   2016 ( 2 ) "S - 23"-"S-24"  2016年03月

    CiNii

  • B-6-120 A Data Center Architecture Based on CCN

    Zhang Lu, Qi Xin, Zhang Di, Sato Takuro

    電子情報通信学会総合大会講演論文集   2016 ( 2 ) 120 - 120  2016年03月

    CiNii

  • Proactive-caching based information centric networking architecture for reliable green communication in intelligent transport system

    Quang N. Nguyen, Mohammad Arifuzzaman, Takuro Sato

    Proceedings of the 2015 ITU Kaleidoscope: Trust in the Information Society, K-2015 - Academic Conference    2016年01月

     概要を見る

    In this article, we construct a concrete model as the prototype of efficient and reliable wireless Information Centric Networking (ICN) within the context of Intelligent Transport System (ITS). This research proposes a novel proactive-caching technique in ICN providing the robust and effective content delivery to the mobile nodes (commuters) for transportation system and fitting numerous ICN mobility scenarios of transportation system thanks to our "smart scheduler". We also propose a wireless ICN architecture which can adapt the power consumption of network nodes to the actual values of their optimized utilizations for greening the transportation communication network. Moreover, we identify that there are currently various ICN-based models and emphasize the need of an official international standard for wireless communication in general and transportation system in particular. Then by evaluating our proposal, we show that our proposal is a promising and feasible contribution for the ITU standardization process of Data Aware Networking (DAN) by integrating Green networking into DAN to combine the benefits of innovated rate-adaptivity and proactive-caching based schemes for achieving highly scalable, reliable and energy-efficient network performance in future transportation Information-centric communication system with data-awareness.

    DOI

    Scopus

    17
    被引用数
    (Scopus)
  • Cost-efficient residential energy management scheme for information-centric networking based home network in smart grid

    Keping Yu, Battulga Davaasambuu, Nam Hoai Nguyenand, Quang Nguyen, Arifuzzaman Mohammad, Takuro Sato

    International Journal of Computer Networks and Communications   8 ( 2 ) 25 - 42  2016年

     概要を見る

    Home network (HOMENET) performs multiple important functions such as energy management, multimedia sharing, lighting and climate control in smart grid (SG). In HOMENET there are numerous challenges among which mobility and security are the basic requirements that need to be addressed with priority. The information-centric networking (ICN) is regarded as the future Internet that subscribes data in a content-centric manner irrespective of its location. Furthermore, it has pecial merit in mobility and security since ICN supports in-network caching and self-contained security, these make ICN a potential solution for home communication fabric. This paper aims to apply the ICN approach on HOMENET system, which we called ICN-HOMENET. Then, a proof-of-concept evaluation is employed to evaluate the effectiveness of the proposed ICN-HOMENET approach in data security, device mobility and efficient content distribution for developing HOMENET system in SG. In addition, we proposed a cost-efficient residential energy management (REM) scheme called ICN-REM scheme for ICN-HOMENET system which encourages consumers to shift the start time of appliances from peak hours to off-peak hours to reduce the energy bills. To the best of our knowledge, this is the first attempt to propose an ICN-based REM scheme for HOMENET system. In this proposal, we not only consider the conflicting requests from appliances and domestic power generation, but also think the energy management unit (EMU) should cooperate with measurement sensors to control some specific appliances in some specific conditions. Moreover, the corresponding performance evaluation validates its correctness and effectiveness.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • スマートグリッドネットワークの効率的運用に関する研究

    周 巍, 文 鄭, 佐藤 拓朗

    日本シミュレーション学会論文誌   8 ( 1 ) 25 - 31  2016年

     概要を見る

    Recently, miniaturization, low cost and standardization activates of the wireless sensor network technologies has been remarkably advanced, because of advancement of the wireless technologies. Especially smart grid is important application of the wireless sensor network technologies. In the smart grid network, the network congestion occurs caused by huge traffic in real time transmission of energy usage data or environment information data in the house or building. It is required to effectively collect the data and improve the network efficiency. We describes the scheme and the results in this paper since we clarified the efficient data transmission based on data fusion method for the energy usage data using Back Propagation (BP) algorithm with Artificial Neural Network.

    DOI CiNii

  • Outage Probability Analysis of NOMA within Massive MIMO Systems

    Di Zhang, Keping Yu, Zheng Wen, Takuro Sato

    2016 IEEE 83RD VEHICULAR TECHNOLOGY CONFERENCE (VTC SPRING)   2016-July  2016年  [査読有り]

     概要を見る

    A Pseudo Double Scattering Channel (PDSC) Matrix assumption is proposed here for downlink Non-Orthogonal Multiple Access (NOMA) within massive Multi-Input Multi-Output (MIMO) systems. Afterwards, outage probability analysis of such a system is investigated. That is, with the aid of random matrix and statistics theories, the Cumulative Probability Distribution (CDF) and also the outage probability performance are addressed. After that, the mathematics derivations obtained here are verified through numerical simulation results, wherein we further find out that with antenna number increasing, the system outage probability performance is reduced.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Integrating Energy Efficiency Mechanism with Components Selection for Massive MIMO Based C-RAN

    Di Zhang, Shahid Mumtaz, Zhenyu Zhou, Takuro Sato

    2016 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS WORKSHOPS (ICC)     74 - 79  2016年  [査読有り]

     概要を見る

    Based on the Cloud-Radio Access Network (C-RAN) structure and massive Multi-Input Multi-Output (MIMO), we propose one comprehensive system model and give the Energy Efficiency (EE) analysis of this system. The C-RAN structure is amended for better antenna control in massive MIMO based C-RAN system model. Furthermore, system EE optimization problem is modeled from a comprehensive way, and its solution is addressed with a convex optimization method plus an offline decision. In EE analysis, apart from the prior literature, Carrier Capacity (CC), antenna, Radio-Frequency (RF) chain, machine room and also the electron circuits are integrally taken into consideration. A positive correlation is observed between CC and the EE performance prior to the optimal value, after this optimal value, further increase CC has little help to EE enhancement.

    DOI

    Scopus

    3
    被引用数
    (Scopus)
  • Content Oriented Surveillance System Based on Information-Centric Network

    Xin Qi, Zheng Wen, Toshitaka Tsuda, Wataru Kameyama, Jiro Katto, Takuro Sato, Kouichi Shibata

    2016 IEEE GLOBECOM WORKSHOPS (GC WKSHPS)    2016年  [査読有り]

     概要を見る

    Urban surveillance systems are being applied in a rapid pace with mature but inefficient solutions. The inefficiency is revealed with two aspects, too concentrated bandwidth and processing requirement. To solve this problem, we proposed a content oriented surveillance system based on Information-Centric Network. However, we can't simply replace TCP/IP streaming structure with named contents streaming structure because it can't improve the surveillance system's efficiency enough. In this paper, we took the ICN network's profits even further with the named contents. Instead of streaming live video to the central data center and processing multiple data stream in the same time, we have designed the nodes to process the captured raw data and produce objective contents for the central data center. With the extremely size difference in raw data and actual valued contents from it, we could apply the method in investigating area people traffic conditions and even in disaster and anti-terrorism scenarios. There was a field experiment performed to evaluate tourists' densities and dressing habits during winter season of March. The experiment expressed the benefits of our system and compared our method with traditional surveillance systems in saving network bandwidth and functionalities.

    DOI

    Scopus

    13
    被引用数
    (Scopus)
  • Performance Analysis of Heterodyne-Detected OCDMA Systems Using PolSK Modulation over a Free-Space Optical Turbulence Channel

    Fan Bai, Yuwei Su, Takuro Sato

    ELECTRONICS   4 ( 4 ) 785 - 798  2015年12月  [査読有り]

     概要を見る

    This paper presents a novel model of heterodyne-detected optical code-division multiple-access (OCDMA) systems employing polarization shift keying (PolSK) modulation over a free-space optical (FSO) turbulence channel. In this article, a new transceiver configuration and detailed analytical model for the proposed system are provided and discussed, taking into consideration the potential of heterodyne detection on mitigating the impact of turbulence-induced irradiance fluctuation on the performance of the proposed system under the gamma-gamma turbulence channel. Furthermore, we derived the closed-form expressions for the system error probability and outage probability, respectively. We determine the advantages of the proposed modeling by performing a comparison with a direct detection scheme obtained from an evaluation of link performance under the same environment conditions. The presented work also shows the most significant impact factor that degrades the performance of the proposed system and indicates that the proposed approach offers an optimum link performance compared to conventional cases.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • Electronic phase transition in hollandite titanates BaxTi8 O16+δ

    Murata, R, Sato, T, Okuda, T, Horibe, Y, Tsukasaki, H, Mori, S, Yamaguchi, N, Sugimoto, K, Kawaguchi, S, Takata, M, Katsufuji, T, Katsufuji, T

    Physical Review B - Condensed Matter and Materials Physics   92 ( 22 )  2015年12月  [査読有り]

     概要を見る

    © 2015 American Physical Society.We studied the physical properties of hollandite titanates, BaxTi8O16+δ, which have double chains of edge-sharing TiO6 octahedra with d electrons in the t2g states. We found that there is an electronic phase transition at ∼220 K, at which various properties exhibit anomalies. This phase transition is characterized by a modulation in the TiO6 chains and a spectral weight transfer of over 2 eV in the optical conductivity spectrum, which are presumably caused by charge and orbital ordering of the Ti t2g electrons.

    DOI

  • Game-theoretic approach to energy-efficient resource allocation in device-to-device underlay communications

    Zhenyui Zhou, Takuro Sato

       2015年10月

  • A Key Management Scheme for Secure Communications of Information Centric Advanced Metering Infrastructure in Smart Grid

    Keping Yu, Mohammad Arifuzzaman, Zheng Wen, Di Zhang, Takuro Sato

    IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT   64 ( 8 ) 2072 - 2085  2015年08月  [査読有り]

     概要を見る

    Advanced metering infrastructure (AMI), as the totality of systems and networks to measure, collect, store, analyze, and use energy usage data, is supposed to be the core component in smart grid. In AMI, there are numerous challenges among which cyber security is a major one that needs to be addressed with priority. The information centric networking (ICN) is a promising architecture for the future Internet that disseminates content based on named data instead of named hosts. The congestion control and self-security can enable more scalable, secure, collaborative, and pervasive networking, these make the ICN a potential network architecture for smart grid. This paper aims to apply the ICN approach on AMI system, which we termed as information centric AMI (ICN-AMI). To the best of our knowledge, this is the first attempt to distribute contents (or requests for contents) based on ICN in AMI system. Moreover, a simulation-based performance evaluation is employed to evaluate the effectiveness of the proposed ICN-AMI approach in traffic control for developing AMI system in smart grid. In addition, we proposed a novel key management scheme (KMS) for a large number of smart meters in this system to ensure confidentiality, integrality, and authentication. To validate the scheme, the security analysis, comparisons are done to demonstrate that the proposed information centric KMS (ICN-KMS) is possible and a promising solution for ICN-AMI system.

    DOI

    Scopus

    153
    被引用数
    (Scopus)
  • Information Centric Networking for Disaster Information Sharing Services

    Zheng Wen, Di Zhang, Keping Yu, Takuro Sato

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E98A ( 8 ) 1610 - 1617  2015年08月  [査読有り]

     概要を見る

    Information Centric Networking (ICN) had merits in terms of mobility, security, power consumption and network traffic. When a large-scale disaster occurred, the current communication system might be fragile and the server based network service might be unavailable due to the damages, network congestions, and power failure, etc. In this paper, we proposed an ICN based Disaster Information Sharing Service (DISS) [1], [2] system. DISS could provide robust information sharing service. Users could publish disaster information as a content message with the help of our DISS. In addition, by utilizing DISS's message naming strategy, users could retrieve disaster information even without a server connection. The ICN based DISS could reduce the probability of network congestion when a large number of simultaneous connections occurring. It could provide server-less service in poor network condition. DISS allows users retrieve disaster information from terminals or ICN nodes. During disasters, sharing information timely and effective could protect people from disaster, ensure people's safety.

    DOI

    Scopus

    14
    被引用数
    (Scopus)
  • Information centric networking for disaster information sharing services

    Zheng Wen, Di Zhang, Keping Yu, Takuro Sato

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences   E98A ( 8 ) 1610 - 1617  2015年08月

     概要を見る

    Information Centric Networking (ICN) had merits in terms of mobility, security, power consumption and network traffic. When a large-scale disaster occurred, the current communication system might be fragile and the server based network service might be unavailable due to the damages, network congestions, and power failure, etc. In this paper, we proposed an ICN based Disaster Information Sharing Service (DISS) [1], [2] system. DISS could provide robust information sharing service. Users could publish disaster information as a content message with the help of our DISS. In addition, by utilizing DISSïs message naming strategy, users could retrieve disaster information even without a server connection. The ICN based DISS could reduce the probability of network congestion when a large number of simultaneous connections occurring. It could provide server-less service in poor network condition. DISS allows users retrieve disaster information from terminals or ICN nodes. During disasters, sharing information timely and effective could protect people from disaster, ensure peopleïs safety.

    DOI

    Scopus

    14
    被引用数
    (Scopus)
  • 2G08 大学における標準化教育の望ましい内容に関する考察((15)グローバル化時代における工学教育-II,口頭発表論文,イノベーションを牽引する工学教育の国際化)

    中西 浩, 佐藤 卓朗

    工学教育研究講演会講演論文集   27 ( 63 ) 368 - 369  2015年08月

    CiNii

  • B-12-5 光無線通信システムにおける伝送特性の評価(B-12.フォトニックネットワーク,一般セッション)

    田邉 亮太, 白 帆, Su Yu Wei, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2015 ( 2 ) 263 - 263  2015年08月

    CiNii

  • B-6-44 CCNベースの災害情報共有アプリケーションにおけるGPSの利用(B-6.ネットワークシステム,一般セッション)

    若菜 実農, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2015 ( 2 ) 44 - 44  2015年08月

    CiNii

  • Game-theoretic approach to energy-efficient resource allocation in device-to-device underlay communications

    Zhenyu Zhou, Mianxiong Dong, Kaoru Ota, Ruifeng Shi, Zhiheng Liu, Takuro Sato

    IET COMMUNICATIONS   9 ( 3 ) 375 - 385  2015年02月  [査読有り]

     概要を見る

    Despite the numerous benefits brought by device-to-device (D2D) communications, the introduction of D2D into cellular networks poses many new challenges in the resource allocation design because of the co-channel interference caused by spectrum reuse and limited battery life of user equipment's (UEs). Most of the previous studies mainly focus on how to maximise the spectral efficiency and ignore the energy consumption of UEs. In this study, the authors study how to maximise each UE's Energy Efficiency (EE) in an interference-limited environment subject to its specific quality of service and maximum transmission power constraints. The authors model the resource allocation problem as a non-cooperative game, in which each player is self-interested and wants to maximise its own EE. A distributed interference-aware energy-efficient resource allocation algorithm is proposed by exploiting the properties of the nonlinear fractional programming. The authors prove that the optimal solution obtained by the proposed algorithm is the Nash equilibrium of the non-cooperative game. The authors also analyse the tradeoff between EE and SE and derive closed-form expressions for EE and SE gaps.

    DOI

    Scopus

    86
    被引用数
    (Scopus)
  • BS-3-46 Towards SE and EE in 5G with NOMA and Massive MIMO Technologies(BS-3. Advanced Technologies in the Design, Management and Control for Future Innovative Communication Network)

    Zhang Di, Yu Keping, Wen Zheng, Su Yuwei, Sato Takuro

    電子情報通信学会総合大会講演論文集   2015 ( 2 ) "S - 95"-"S-96"  2015年02月

     概要を見る

    In 5G research the spectrum efficiency (SE) and energy efficiency (EE) are two crucial issue. Some scholars propose the Massive Multiple-Input Multiple-Output (Massive MIMO) technology as a essential element to achieve the targets. In addition, the non-orthogonal multiple access (NOMA) and mm Wave technologies are proposed towards SE in 5G. In this paper, apart from the previous studies, we study the EE issue while combining the massive MIMO and NOMA together. Which can take advantage of the NOMA for better SE and antenna selection for better EE performance within the background of massive MIMO in 5G.

    CiNii

  • BS-3-28 An Analysis of Energy Consumption between IP-Based Network and ICN for Green Networking(BS-3. Advanced Technologies in the Design, Management and Control for Future Innovative Communication Network)

    Zaw Yin Yin, Nguyen Quang. N, Sato Takuro

    電子情報通信学会総合大会講演論文集   2015 ( 2 ) "S - 62"-"S-63"  2015年02月

    CiNii

  • BS-3-13 A Novel Green Proactive-Caching Scheme for Mobility in Information Centric Networking(BS-3. Advanced Technologies in the Design, Management and Control for Future Innovative Communication Network)

    Nguyen Quang N, Sato Takuro

    電子情報通信学会総合大会講演論文集   2015 ( 2 ) "S - 34"-"S-35"  2015年02月

     概要を見る

    In order to provide the robust and energy-efficiency contents delivery to the mobile terminals in Information Centric Networking (ICN), this paper proposes a dynamic proactive-scheme and evaluates its performance as an effective mechanism for green mobility in ICN. In our scheme, when a mobile node expresses an Interest for a content then neighbor Aggregation Nodes (possible future points of attachment) also generate the "fake interest" for this content to the Content Provider. As a result, after the handoff, when the mobile node re-issues the same interest, the desired content can be found en-route and can be retrieved immediately. To diminish the ICN energy consumption by utilizing this scheme (the interest needs not to travel to the Content Server), we design different operating modes for the server based on the interest traffic. We verify the effectiveness and reliability of our proposed scheme by simulating the model with ndnSIM.

    CiNii

  • B-6-119 Performance of ICN for large-scale data in Smart Grid

    Kovi Aduayom Ahego, Yu Keping, Zhang Di, Sato Takuro

    電子情報通信学会総合大会講演論文集   2015 ( 2 ) 119 - 119  2015年02月

     概要を見る

    The information exchange in the power grid has been undergoing through crucial changes. With the application of advanced Information and Communication Technologies (ICT) to the existing power network; the future grid sees incredible enhancements. However the huge amount of data to transfer over the network becomes challenging. Many literatures show the benefits of applying Information-Centric Network to the power system. In this paper we propose an application of 1CN to Smart Grid system. We evaluate the robustness of the ICN over IP.

    CiNii

  • B-6-108 ICNベース災害情報共有システム(B-6.ネットワークシステム,一般セッション)

    張 成成, 文 鄭, 佐藤 拓朗

    電子情報通信学会総合大会講演論文集   2015 ( 2 ) 108 - 108  2015年02月

    CiNii

  • Self-optimization of handover parameters for long-term evolution with dual wireless mobile relay nodes

    Battulga Davaasambuu, Keping Yu, Takuro Sato

    Future Internet   7 ( 2 ) 196 - 213  2015年

     概要を見る

    In recent years, train passengers have been transferring increasing amounts of data using mobile devices. Wireless networks with mobile relay nodes support broadband wireless communications for passengers of such vehicles using backhaul links. However, the mobility management entity reuses the handover of existing user equipment, resulting in the handover of the Long-Term Evolution network being unsuitable for user equipment within the cabins of vehicles traveling at high speed. In this paper, we propose a self-optimizing handover hysteresis scheme with dual mobile relay nodes for wireless networks in high-speed mobile environments. The proposed mechanism tunes the hysteresis and cell individual offset handover parameters based on the velocity of the vehicle and the handover performance indicator, which affects the handover triggering decision and performance. The results of simulations conducted in which the performance of the proposed scheme was compared to that of an existing scheme show that the proposed scheme can reduce the number of radio link failures and service interruptions during handover procedures.

    DOI

    Scopus

    16
    被引用数
    (Scopus)
  • Locating the Content in the Locality: ICN Caching and Routing Strategy Revisited

    M. Arifuzzaman, Keping. Yu, Quang. N. Nguyen, Sato. Takuro

    2015 EUROPEAN CONFERENCE ON NETWORKS AND COMMUNICATIONS (EUCNC)     423 - 428  2015年  [査読有り]

     概要を見る

    In Information Centric Networking (ICN), besides Off-path caching, On-path caching is an integrated caching solution with-in an ISP's local network. However, in On-path caching, content is cached en-route in the backward path towards the Interest generator and local RENE1/NRS2 (in routing through name resolution) or FIB3 (in name-based routing) is not aware of the cached data. Hence, the most widely used intra-domain routing protocol and their forwarding strategy cannot address all available temporary cached copies of content. Thus, on-path caching strategy usually suffers from either of the two drawbacks-1) too many replications within AS (Autonomous system) which do not add substantial value in terms of cache resource utilization. 2) An attempt to minimize redundancy ends up with the cost of fetching more copy of the same content from the repository (i.e., the closest cache copy is unknown/not en-route). We propose an integrated routing and caching solution which reduces the caching redundancy and maximize the probability of finding nearby cached content, resulting in efficient utilization of available cache resources of ISP's as a whole. We introduce novel concepts of naming the content router and caching the content's cache-route to address the issue. We leverage NDN node architecture and the forwarding plane/strategy (of routing) as well to achieve our goal.

  • Information Centric Networking for Disaster Information Sharing Services

    WEN Zheng, ZHANG Di, YU Keping, SATO Takuro

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences   98 ( 8 ) 1610 - 1617  2015年

     概要を見る

    Information Centric Networking (ICN) had merits in terms of mobility, security, power consumption and network traffic. When a large-scale disaster occurred, the current communication system might be fragile and the server based network service might be unavailable due to the damages, network congestions, and power failure, etc. In this paper, we proposed an ICN based Disaster Information Sharing Service (DISS) [1], [2] system. DISS could provide robust information sharing service. Users could publish disaster information as a content message with the help of our DISS. In addition, by utilizing DISSs message naming strategy, users could retrieve disaster information even without a server connection. The ICN based DISS could reduce the probability of network congestion when a large number of simultaneous connections occurring. It could provide server-less service in poor network condition. DISS allows users retrieve disaster information from terminals or ICN nodes. During disasters, sharing information timely and effective could protect people from disaster, ensure peoples safety.

    CiNii

  • 早稲田大学における企業ビジネスと標準化教育

    モハマッド アリフザマ, 周 振宇, 春田 かすみ, 佐藤 拓朗

    工学教育   63 ( 3 ) 3_18 - 3_21  2015年

     概要を見る

    This paper aims to focus on the standardization process and its consequences in the field of information and communication technologies (ICT) , with a view to understanding the significance of the standardization in academia and inclusion to this subject in academic curricula. Particularly, we take the scenario of cellular communication industry and as an evolutionary technology we take CDMA (Code Division Multiple Access) as a case study. Game theory is chosen as a tool for analysis of the business decision of stakeholder of an innovative technology. CDMA' s spread spectrum approach was unique. However, the good technology doesn' t always win out. A good example is VHS ; which is successful and won out the market though technically inferior to Betamax. For the case of CDMA, we explain the case of good technological innovation, strategic management by the innovator and the role of standardization as a pre-requisite to win the market. We designed the game based on the scenario while a technology licensor (Qualcomm) simultaneously works as a product manufacturer and make a role overlapping with the licensee (Motorola, Nokia, Ericson etc) . We also give a brief mathematical analysis with the Stackelberg leadership Game Model for the Qualcomm' s Royalty and Chip business.

    DOI CiNii

  • An Optimal Information Centric Networking Model for the Future Green Network

    Quang N. Nguyen, M. Arifuzzaman, T. Miyamoto, Sato Takuro

    2015 IEEE 12TH INTERNATIONAL SYMPOSIUM ON AUTONOMOUS DECENTRALIZED SYSTEMS ISADS 2015     272 - 277  2015年  [査読有り]

     概要を見る

    In order to address the energy flaw and enhance the energy efficiency of Information Centric Networking (ICN) Architecture, this research proposes an innovated optimal ICN model with adaptive power consumption ability based on the popularity of the content to adapt content router link rate to its real-time utilization for optimizing the ICN router operating power value and based on the interest traffic to the server to select the optimal working mode for the server/content provider. With this dynamic control/adaptive mechanism, the proposed architecture can provide higher reliability with dynamic energy efficiency consumption and better cost-effectiveness for the future ICN infrastructure system to reduce electricity usage, cost and greenhouse gases, then solve global warming issues.

    DOI

    Scopus

    17
    被引用数
    (Scopus)
  • Energy Efficiency Scheme with Cellular Partition Zooming for Massive MIMO Systems

    Di Zhang, Keping Yu, Zhenyu Zhou, Takuro Sato

    2015 IEEE 12TH INTERNATIONAL SYMPOSIUM ON AUTONOMOUS DECENTRALIZED SYSTEMS ISADS 2015     266 - 271  2015年  [査読有り]

     概要を見る

    Massive Multiple-Input Multiple-Output (Massive MIMO) has been realized as a promising technology element for 5G wireless mobile communications, in which Spectral Efficiency (SE) and Energy Efficiency (EE) are two critical issues. Prior estimates have indicated that 57% energy consumption of cellular system comes from the operator, mostly used to feed the base station (BS). Yet previously, the User Equipment (UE) is focused on while studying the EE issue instead of BS. In this case, in this paper, an EE scheme that focuses on the optimization of BS energy consumption is proposed. Apart from the previous studies, which divides the coverage area by circuit section, the coverage area is divided by fan section with the help of Propagation theory for zoom in or zoom out. In the proposal, transmission model and parameters related to EE is deduced first. Afterwards, the Cellular Partition Zooming (CPZ) scheme is proposed where the BS can zoom in to maintain the coverage area or zoom out to save the energy. Comprehensive simulation results demonstrate that CPZ presents better EE performance with negligible impact on the transmission rate.

    DOI

    Scopus

    19
    被引用数
    (Scopus)
  • Exploiting Correlation for MMSE Channel Estimation in Massive MIMO Systems with RF-Impairments

    Semaganga Frank, Battulga Davaasambu, Takuro Sato

    2015 IEEE INTERNATIONAL CONFERENCE ON COMPUTER AND COMMUNICATIONS (ICCC)     324 - 328  2015年  [査読有り]

     概要を見る

    The Large Scale Antenna System is expected to bring significant improvements to overall Communication System Performance. However the use of so many antennas in Massive Multiple Inputs Multiple Outputs (Massive MIMO) architectures highlights the cost implication of the technology. It is therefore possible that Massive MIMO may be deployed using low cost equipment to avoid HUGE implementation costs. The use of Low Cost Equipment will results into significant Radio Frequency Impairments (RF-Impairments) such as Phase Noise, IQ Imbalance and Nonlinearities, which will affect the overall system performance. Among other aspects channel estimations will also be affected since the signal used for these estimations will be affected by the RF-Impairments. This paper analyzes a way to exploit correlation during Minimum Mean Square Error (MMSE) Channel Estimation of a Massive MIMO System in presence of aggregated RF-Impairments (i.e. combined effects of the impairments). Specifically it derived the statistical distribution of the equivalent aggregated error/noise term using statistical identities and uses the derived term to obtain temporal channel estimation error and consequently the correlation matrix necessary to minimizes the channel Mean Square Error (MSE) of the channel estimate.

    DOI

    Scopus

  • Performance Evaluation of Proactive Content Caching for Mobile Video through 50-User Field Experiment

    Kenji Kanai, Takeshi Muto, Jiro Katto, Wataru Kameyama, Yong-Jin Park, Takuro Sato, Shinya Yamamura, Tomoyuki Furutono, Takafumi Saito, Hirohide Mikami, Kaoru Kusachi, Toshitaka Tsuda

    2015 IEEE GLOBECOM WORKSHOPS (GC WKSHPS)    2015年  [査読有り]

     概要を見る

    Providing robust content delivery service, such as Video on Demand, with efficient wireless resource usage is important for mobile users. To achieve this, we have proposed a proactive content caching scheme utilizing transportation systems (e.g., train). Because our previous prototype is immature and has a scalability issue, in this paper, we introduce an efficient transmission mechanism of Interest messages to improve throughput efficiency in mobile NDN, develop two prototypes based on NDN and HTTP, and then evaluate prototype performances by performing larger-scale field experiments on actual commercial railroad line. Evaluations conclude that our system can achieve high efficient content transfer and fully utilize wireless network bandwidth. As a result, our system can provide high-quality video streaming for up to 50 users simultaneously.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • Energy efficiency and spectral efficiency tradeoff in device-to-device (D2D) communications

    Zhenyu Zhou, Mianxiong Dong, Kaoru Ota, Jun Wu, Takuro Sato

    IEEE Wireless Communications Letters   3 ( 5 ) 485 - 488  2014年10月  [査読有り]

     概要を見る

    In this letter, we investigate the tradeoff between energy efficiency (EE) and spectral efficiency (SE) in device-to-device communications underlaying cellular networks with uplink channel reuse. The resource allocation problem is modeled as a noncooperative game, in which each user equipment is self-interested and wants to maximize its own EE. Given the SE requirement and maximum transmission power constraints, a distributed energy-efficient resource allocation algorithm is proposed by exploiting the properties of the nonlinear fractional programming. The relationships between the EE and SE tradeoff of the proposed algorithm and system parameters are analyzed and verified through computer simulations.

    DOI

    Scopus

    182
    被引用数
    (Scopus)
  • B-1-25 列車内における電波伝搬特性(B-1.アンテナ・伝搬A(電波伝搬,非通信利用),一般セッション)

    杉本 涼, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2014 ( 1 ) 25 - 25  2014年09月

    CiNii

  • A-18-2 災害時における通信手段の行動パターンのモデル化(A-18.安全性,一般セッション)

    鈴木 達也, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2014   123 - 123  2014年09月

    CiNii

  • 2H19 早稲田大学標準化教育の学部展開について((07)高大院連携/(17)国際化時代における工学教育-I,口頭発表)

    佐藤 拓朗

    工学教育研究講演会講演論文集   26 ( 62 ) 404 - 405  2014年08月

    CiNii

  • ビームフォーミングネットワークを用いた高速鉄道向けの角度誤差対応無線システム(一般,初めての研究会,鉄道,車車間・路車間通信,リソース制御,スケジューリング,国際ワークショップ,無線通信一般)

    陳 立, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   114 ( 86 ) 87 - 92  2014年06月

     概要を見る

    移動中での高速インターネット環境が整備される中,新幹線やリニア新幹線での実用化に向けて無線問題が上がった.今後更なる普及が見込まれるクラウドサービスを支えるためには,更なる安定かつ高速な無線通信環境が要求される.本稿では,GPS(Global Positioning System)の測位誤差を考慮する事で,移動局の位置情報の誤差に対するスループットの低下を補償する一手法を提案する.通信状態に応じて送信および受信アンテナ数を適応的に切り換えるビームマネージメント・アルゴリズムにより,移動局の測位誤差による影響を最小限に抑える事で,平均スループットの改善を得た.

    CiNii

  • 交通機関を活用したコンテンツ先回り配信システムのフィールド実験評価

    金井 謙治, 武藤 健史, 木皿 寛人, 甲藤 二郎, 津田 俊隆, 亀山 渉, 朴 容震, 佐藤 拓朗

    情報処理学会研究報告. MBL, [モバイルコンピューティングとユビキタス通信研究会研究報告]   2014 ( 30 ) 1 - 6  2014年05月

     概要を見る

    筆者らは,近年のモバイルトラフイックの爆発的な増加に対処するために,交通機関を活用したコンテンツ先回り配信システムを提案している.本稿では,その性能評価をするために,フィールド実験として,試験線を用いた実車両実験を行った.従来の CDN を想定したセルラーによる配信と比較し,先回り配信システムの有効性を明らかにした.

    CiNii

  • SSB-QAM変調方式の一研究(その2) : AWGN環境下におけるBER特性の理論検討(アドホック・センサネットワーク・MANET,モバイルネットワーク,M2M通信制御,無線LAN(Wi-Fi),IEEE802.15(ZigBee)及び一般)

    太田 現一郎, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   114 ( 30 ) 67 - 72  2014年05月

     概要を見る

    筆者らが研究するSSB-QPSK変復調方式に多値化対策を提案し、SSB-QAM方式を提案した。QPSKモードではrolloff率を0に近づけた場合に4bit/s/Hzとなる。また多値化変調16QAM、64QAMにおいてもOFDMの性能の2倍になることを原理的に示せるとした。本報告では、本提案方式がBit誤り率の劣化要因として及ぼす範囲を検証した。またAWGNに対しては本方式が相関検波と同様の作用を有することで、SSBとしてのCNR劣化作用を克服できることを示した。

    CiNii

  • 交通機関を活用したコンテンツ先回り配信システムのフィールド実験評価

    金井 謙治, 武藤 健史, 木皿 寛人, 甲藤 二郎, 津田 俊隆, 亀山 渉, 朴 容震, 佐藤 拓朗

    情報処理学会研究報告. マルチメディア通信と分散処理研究会報告   2014 ( 30 ) 1 - 6  2014年05月

     概要を見る

    筆者らは,近年のモバイルトラフイックの爆発的な増加に対処するために,交通機関を活用したコンテンツ先回り配信システムを提案している.本稿では,その性能評価をするために,フィールド実験として,試験線を用いた実車両実験を行った.従来の CDN を想定したセルラーによる配信と比較し,先回り配信システムの有効性を明らかにした.

    CiNii

  • B-6-92 CCNにおける電気自動車を活用した最適移動情報通信(B-6.ネットワークシステム,一般セッション)

    沈 揚, 文 鄭, 朱 力, 呉 超, 趙 鄭戈, 余 娜, 佐藤 拓朗

    電子情報通信学会総合大会講演論文集   2014 ( 2 ) 92 - 92  2014年03月

    CiNii

  • B-6-88 交通機関を利用したコンテンツ配信システム(B-6.ネットワークシステム,一般セッション)

    佐藤 拓朗, 朴 容震, 津田 俊隆, 後藤 滋樹, 田中 良明, 亀山 渉, 嶋本 薫, 甲藤 二郎, 市野 将嗣

    電子情報通信学会総合大会講演論文集   2014 ( 2 ) 88 - 88  2014年03月

    CiNii

  • B-6-85 CCNにおける効率的VODサービスの検討(B-6.ネットワークシステム,一般セッション)

    趙 鄭戈, 文 鄭, 朱 力, 呉 超, 沈 揚, 佐藤 拓朗

    電子情報通信学会総合大会講演論文集   2014 ( 2 ) 85 - 85  2014年03月

    CiNii

  • ストレステスト-続報(<小特集>これからを見据えた情報通信)

    余 那, 佐藤 拓朗

    シミュレーション   33 ( 1 ) 9 - 10  2014年03月

    CiNii

  • CCNにおける効率的VoDサービスの検討(移動通信ワークショップ)

    趙 鄭戈, 文 鄭, 朱 力, 呉 超, 沈 揚, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   113 ( 456 ) 523 - 526  2014年02月

     概要を見る

    コンテンツセントリックネットワーク(Contents Centric Network; CCN)は、従来、ノードを基準として行われていた通信形態をコンテンツを主体として行う形態へと変革させる新しい通信パラダイムである.本文はその特徴を利用して、CCNにおけるVoDサービスについて研究している.そして、新たな効率的キャッシュアルゴリズムの検討を行った。

    CiNii

  • 災害シナリオにおけるCCN事前キャッシング方案 : 一般講演(シミュレーション)(移動通信ワークショップ)

    朱 力, 文 鄭, 呉 超, 趙 鄭戈, 沈 揚, 余 娜, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   113 ( 456 ) 511 - 514  2014年02月

     概要を見る

    本論文では、情報通信技術(ICT)のアプローチの近代的な概念を使用して、災害シナリオのコンテンツ中心ネットワーク(CCN)スキームを提示する。コンテンツ中心ネットワークは必要がある場所に関連するコンテンツをプッシュすることを特徴として新しいネットワークである。そのキャッシュとリポジトリ機能を使用して、バックボーンネットワークの輻輳や遅延を低減することができる。災害シナリオでは、完備していないネットワーク環境のため、通信障害が発生しやすい。また、被災地の内と外両側から通常より災害に関する情報配信の高い需要、がバックボーンネットワークに大きな圧力をもたらす。事前キャッシュされた内容を詰め込みするリポジトリ機能を持つコンテンツ中心ネットワークは、キャッシュヒットとホップ距離で、堅牢性と高い性能を表す。バックボーンネットワークにおける輻輳やスループットの圧力を解放に活用できる。

    CiNii

  • SSB-QPSK変調方式の多値化の一研究 : 4層SSB-QAM変調方式(移動通信ワークショップ)

    太田 現一郎, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   113 ( 456 ) 37 - 42  2014年02月

     概要を見る

    筆者らが研究するSSB-QPSK変復調方式において、新たな検波方式を考案した。この結果、最大の課題の一つであった隣接シンボル間干渉を理論的に皆無にした。これにより希望波の振幅情報をほぼ干渉なく復調できることとなり、シンボル信号の多値化が可能となり、OFDM方式の持つ周波数利用効率2bit/s/Hzに匹敵する新たな変復調方式を具現化した。NyquistフィルタのRolloff率を0に近づけた場合の周波数利用効率は4bit/s/Hzとなる。今後、SSBキャリアのインターリーブ化を図りOFDMタイプのマルチキャリア化による新変復調方式を検討する。

    CiNii

  • A Proposal for Dynamic WLAN Selection for Mobile Data Offloading in Heterogeneous Network

    Nam Nguyen, Takuro Sato

    2014 IEEE 79TH VEHICULAR TECHNOLOGY CONFERENCE (VTC-SPRING)    2014年  [査読有り]

     概要を見る

    In this paper, we present a new Wi-Fi roaming selection scheme as a solution for macro-cell traffic offloading. The idea is to take advantage of the Access Network Discovery and Selection Function (ANDSF) policies and the IEEE 802.11k standard for Wi-Fi access point (AP) selecting process. Although ANDSF can provide the list of candidate APs with preferred selection policies, due to the fact that ANDSF's selection policies are static and are not based on the real-time network condition, it cannot be considered as a solution for traffic steering and offloading issue in heterogeneous network. In our proposed scheme for Wi-Fi offloading, we address this issue by taking into account the real-time traffic load of Wi-Fi AP as one criterion for selection. We simulate and verify the proposed scheme on NCTUNS 6.0. The simulation result shows that our scheme can effectively offload the data traffic from cellular network to Wi-Fi and improve the overall network throughput.

  • Stackelberg-Game based Distributed Energy-Aware Resource Allocation in Device-to-Device Communications

    Zhenyu Zhou, Mianxiong Dong, Kaoru Ota, Bo Gu, Takuro Sato

    2014 IEEE International Conference on Communication Systems (ICCS)     11 - 15  2014年  [査読有り]

     概要を見る

    Despite the numerous benefits brought by device-to-device (D2D) communications, user equipments (UEs) are typically handheld devices with limited battery life and can quickly run out of battery if power consumption is ignored in the system design. Compared to previous works that have not taken power consumption into consideration, we model the utility function as a weighted sum of achievable transmission rate, power consumption, and interference revenue (or cost) based on multi-objective optimization (MOO) methods. The resource allocation process is modeled as a two-stage Stackelberg game with transmission power and quality of service (QoS) constraints, in which cellular UEs are game leaders who charges D2D UEs for reusing channels, and D2D UEs are game followers who buy channel resources from cellular UEs. Simulation results show the effectiveness of the proposed algorithm and how the system parameters affect the pricing and transmission power strategies.

  • Error Probability Analysis of Joint Signal Detection with Base Station Sleeping and Cooperation

    Zhenyu Zhou, Mianxiong Dong, Kaoru Ota, Zhiheng Liu, Jun Wu, Takuro Sato

    2014 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS (ICC)     2443 - 2448  2014年  [査読有り]

     概要を見る

    In this paper, we consider the application scenario where multiple Base Stations (BSs) cooperate to transmit signals to a mobile terminal in the same frequency and any of the cooperative BSs is allowed to enter into sleeping mode to save energy. The mobile terminal employs the Joint Maximum Likelihood Sequence Estimation (JMLSE) based Joint Signal Detection (JSD) to simultaneously detect multiple co-channel signals and judge whether a cooperative BS is active or not. The detection error probability of JSD is analyzed in this paper. For the case of BS sleeping, the error probability is computed based on a tentative modulation scheme which incorporates the M constellation points of conventional M-QAM and the additional constellation point 0. For the case of BS cooperation, the error probability bounds are derived based on a genie-aided receiver, and a new Tighter Lower Bound (TLB) is derived by replacing the genie with a less generous one. Simulation results have verified that the computed error probability can provide a rapid and accurate estimation of the Symbol Error Rate (SER) performance.

  • Distributed Interference-Aware Energy-Efficient Resource Allocation for Device-to-Device Communications Underlaying Cellular Networks

    Zhenyu Zhou, Mianxiong Dong, Kaoru Ota, Jun Wu, Takuro Sato

    2014 IEEE GLOBAL COMMUNICATIONS CONFERENCE (GLOBECOM 2014)     4454 - 4459  2014年  [査読有り]

     概要を見る

    The introduction of device-to-device (D2D) into cellular networks poses many new challenges in the resource allocation design due to the co-channel interference caused by spectrum reuse and limited battery life of user equipments (UEs). In this paper, we propose a distributed interference-aware energyefficient resource allocation algorithm to maximize each UE's energy efficiency (EE) subject to its specific quality of service (QoS) and maximum transmission power constraints. We model the resource allocation problem as a noncooperative game, in which each player is self-interested and wants to maximize its own EE. The formulated EE maximization problem is a nonconvex problem and is transformed into a convex optimization problem by exploiting the properties of the nonlinear fractional programming. An iterative optimization algorithm is proposed and verified through computer simulations.

  • Effective Data Gathering and Energy Efficient Communication Protocol in Wireless Sensor Networks employing UAV

    Say Sotheara, Kento Aso, Naoto Aomi, Shigeru Shimamoto

    2014 IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE (WCNC)     2342 - 2347  2014年  [査読有り]

     概要を見る

    This paper proposes the effective data gathering and energy efficient communication scheme for Wireless Sensor Networks employing Unmanned Aerial Vehicle. In this scheme, we minimize the number of redundant sensors communicating with UAV by assigning the sensors inside the coverage area of UAV's beacon signal into different priority groups. Once the priority segments, Circularly Optimized Frame Selection (COFS), are defined, data communication is handled from higher to lower transmission priority frame sequentially. The work presented in the paper is based on multi-hop approach. Therefore, the plausible algorithms employing the scheme COFS are proposed to engage in effective data collection. As a result, both the proposed scheme and algorithms are significant to obtain low energy consumption as well as increase the lifetime of sensors inside the network. The energy consumption model is also presented. This study is confirmed by simulating the WSN-UAV system employing our proposed model.

  • Effective Data Gathering and Energy Efficient Communication Protocol in Wireless Sensor Networks employing UAV

    Say Sotheara, Kento Aso, Naoto Aomi, Shigeru Shimamoto

    2014 IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE (WCNC)     2342 - 2347  2014年  [査読有り]

     概要を見る

    This paper proposes the effective data gathering and energy efficient communication scheme for Wireless Sensor Networks employing Unmanned Aerial Vehicle. In this scheme, we minimize the number of redundant sensors communicating with UAV by assigning the sensors inside the coverage area of UAV's beacon signal into different priority groups. Once the priority segments, Circularly Optimized Frame Selection (COFS), are defined, data communication is handled from higher to lower transmission priority frame sequentially. The work presented in the paper is based on multi-hop approach. Therefore, the plausible algorithms employing the scheme COFS are proposed to engage in effective data collection. As a result, both the proposed scheme and algorithms are significant to obtain low energy consumption as well as increase the lifetime of sensors inside the network. The energy consumption model is also presented. This study is confirmed by simulating the WSN-UAV system employing our proposed model.

  • A Key Management Scheme for Secure Communications of Information Centric Advanced Metering Infrastructure in Smart Grid

    Keping Yu, Di Zhang, Arifuzzaman Mohammad, Nam Hoai Nguyen, Takuro Sato

    2014 INTERNATIONAL CONFERENCE ON POWER SYSTEM TECHNOLOGY (POWERCON)     2019 - 2024  2014年  [査読有り]

     概要を見る

    The Advanced Metering Infrastructure (AMI) is the core component in Smart Grid. The cyber security is one of the major concerns and challenges should be prior considered. The Information Centric Networking (ICN) is a promising architecture for the future Internet that disseminates content based on named data instead of named hosts. It will be involved into Smart Grid because its excellent congestion control and self-security can enable more scalable, secure, collaborative and pervasive networking. This paper aims at proposing an Information Centric AMI (ICN-AMI) structure and a novel key management scheme (KMS) for a large number of smart meters (SMs) in this system to ensure confidentiality, integrality and authentication. To validate the scheme, the security analysis, comparisons and NDNsim simulation are done to demonstrate that the proposed ICN-KMS is possible solution for ICN-AMI system.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Proactive Content Caching utilizing Transportation Systems and its Evaluation by Field Experiment

    Kenji Kanai, Takeshi Muto, Hiroto Kisara, Jiro Katto, Toshitaka Tsuda, Wataru Kameyama, Yong-Jin Park, Takuro Sato

    2014 IEEE GLOBAL COMMUNICATIONS CONFERENCE (GLOBECOM 2014)     1382 - 1387  2014年  [査読有り]

     概要を見る

    Providing robust content delivery along with efficient wireless resource usage is important for next generation wireless networks. To achieve this, we propose a proactive content caching scheme utilizing transportation systems, especially trains. In our system, we place content servers with CCN capability to every train and station. Segments of video contents are pre-cached by the station servers before trains arrive at stations. Trains receive the contents via high-speed wireless transport while they stop at the stations. We develop a prototype system based on IP and CCN Hybrid protocols. We evaluate its performance by field experiment and compare with traditional CDN scenarios using cellular networks. Evaluations conclude that our system can achieve high-speed and high-reliable video delivery without freezing.

    DOI

    Scopus

    16
    被引用数
    (Scopus)
  • A Cost Based Handoff Hysteresis Scheme in Wireless Mobile Relay Node

    Battulga Davaasambuu, Takuro Sato

    2014 IEEE 80TH VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL)    2014年  [査読有り]

     概要を見る

    In the long term evolution (LTE), Relay node architectures included in order to increase the coverage and system capacity. But designed in the LTE-A and release 12, the Relay node architectures supported mobility. An LTE system based on the network-controlled hard handoff and handoff reuses existing user equipment. In this paper, we propose an adaptive handoff hysteresis scheme with a simplified cost function considering some dominant factors for Mobile Relay such as the load difference target cells, the velocity, and the service type. The performances of the traditional handoff scheme and the proposal are analyzed and compared in details.

    DOI

    Scopus

    3
    被引用数
    (Scopus)
  • Impact of electric battery's degradation on economic and energy saving characteristics of residential photovoltaic system

    Yoshida, Akira, Yoshida, Akira, Sato, Tomikazu, Amano, Yoshiharu, Amano, Yoshiharu, Ito, Koichi

    Proceedings of the 27th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, ECOS 2014    2014年01月

     概要を見る

    In Japan a feed-in tariff scheme has promoted the utilization of photovoltaic power generators in combination with electric batteries. Although many researchers have assessed the operations of grid-connected photovoltaic systems with electric batteries, little attention has been paid to the impact of the electric batteries' degradation characteristics. This paper presents an evaluation of the operation of a grid-connected photovoltaic/electric battery system in a house from energy saving and economy viewpoints. We constructed a long-term operational optimization model considering the degradation characteristics of the electric battery. This model contains two objective functions: energy saving and operating cost. We set a scenario of power rate and photovoltaic/battery system configurations. In order to reveal the optimal operational strategy of the photovoltaic/battery system, the multi-objective optimization problem was solved. As a result, pareto optimal solutions were obtained, and trade-off relationships between economy and energy saving are presented. In this study, the utilization of the grid-connected photovoltaic system with an electric battery was expected to be effective in an energy saving priority operation.

  • CCN-AMI: Performance Evaluation of Content-Centric Networking Approach for Advanced Metering Infrastructure in Smart Grid

    Keping Yu, Li Zhu, Zheng Wen, Arifuzzaman Mohammad, Zhenyu Zhou, Takuro Sato

    2014 IEEE INTERNATIONAL WORKSHOP ON APPLIED MEASUREMENTS FOR POWER SYSTEMS PROCEEDINGS (AMPS)     121 - +  2014年  [査読有り]

     概要を見る

    Advanced Metering Infrastructure (AMI), as the totality of systems and networks to measure, collect, store, analyze, and use energy usage data, is supposed to the key component that should be preferentially constructed for smart grid. In the meanwhile, content-centric networking (CCN) is perceived as a promising approach where the content itself becomes the core of communication instead of the address or location in the future internet research. Based on its caching advantage, it is widely believed that CCN can effectively reduce the AMI network bandwidth. This paper aims to apply the CCN approach on AMI system, which is called CCN-AMI. To the best of our knowledge, this is the first attempt to distribute contents or requests based on CCN in AMI system. Moreover, a simulation-based performance evaluation is employed to evaluate the effectiveness of the proposed CCN-AMI approach in traffic control for developing AMI system in smart grid.

    DOI

    Scopus

    9
    被引用数
    (Scopus)
  • CONTENT DISTRIBUTION IN INFORMATION CENTRIC NETWORK: ECONOMIC INCENTIVE ANALYSIS IN GAME THEORETIC APPROACH

    Arifuzzaman Mohammad, Keping Yu, Sato Takuro

    PROCEEDINGS OF THE 2014 ITU KALEIDOSCOPE ACADEMIC CONFERENCE: LIVING IN A CONVERGED WORLD: IMPOSSIBLE WITHOUT STANDARDS?     215 - 220  2014年  [査読有り]

     概要を見る

    The contributions of this paper are twofold. Firstly, we analyze the decision making problem of caching contents by the network players of Information Centric Networking (ICN) from a game theoretic perspective. We also mention a possible content distribution model for ICN. By our proposed game theory, different network players can find the optimality taking into consideration which benefits them with optimum revenue. Secondly, we present a solution for Live Streaming Media broadcast in ICN and analyze the economic part with a decision tree. We believe, our paper clearly shows the economic incentives for major network players which can stand as a motivation to achieve the faster accommodation of ICN architecture. Besides, we identify some standardization issue in ICN architecture and we emphasize on the need for a common standard for content routers (CR) so that as a node in the ICN, CR ensure scalable content delivery as well as its functionalities match with the Internet open standard philosophy.

    DOI

    Scopus

    9
    被引用数
    (Scopus)
  • A Key Management Scheme for Secure Communications of Information Centric Advanced Metering Infrastructure in Smart Grid

    Keping Yu, Di Zhang, Arifuzzaman Mohammad, Nam Hoai Nguyen, Takuro Sato

    2014 INTERNATIONAL CONFERENCE ON POWER SYSTEM TECHNOLOGY (POWERCON)   64 ( 8 ) 2072 - 2085  2014年  [査読有り]

     概要を見る

    The Advanced Metering Infrastructure (AMI) is the core component in Smart Grid. The cyber security is one of the major concerns and challenges should be prior considered. The Information Centric Networking (ICN) is a promising architecture for the future Internet that disseminates content based on named data instead of named hosts. It will be involved into Smart Grid because its excellent congestion control and self-security can enable more scalable, secure, collaborative and pervasive networking. This paper aims at proposing an Information Centric AMI (ICN-AMI) structure and a novel key management scheme (KMS) for a large number of smart meters (SMs) in this system to ensure confidentiality, integrality and authentication. To validate the scheme, the security analysis, comparisons and NDNsim simulation are done to demonstrate that the proposed ICN-KMS is possible solution for ICN-AMI system.

    DOI

    Scopus

    153
    被引用数
    (Scopus)
  • 災害システムのCCN応用に関する研究(一般,モバイル,アドホック,ユビキタス,無線,セキュリティ,マルチアクセス,アクセスネットワーク・UserNetworklnterface,Homeネットワーク,一般)

    余 娜, Mohammad Arifuzzaman, 余 恪平, 佐藤 拓朗

    電子情報通信学会技術研究報告. NS, ネットワークシステム   113 ( 360 ) 1 - 6  2013年12月

     概要を見る

    災害時には災害情報の発信と受信のために,膨大なアクセスが短時間にネットワークに対して行われる.それら通信サービスに対応するための通信処理能力が大幅に不足することから,通信途絶等の状態が生じたことを踏まえ,通信ネットワークの耐災害性強化に向けるネットワークを統合的に構成することが必要である.本研究では,ネットワーク全体のトラヒックを削減するには,コンテンツ中心ネットワークを用い,ルータ上でキャッシュを行う方法を検討する.さらに,キャッシュヒット率の向上を図るために,パスキャパシティとコンテンツ人気度を考慮するキャッシュを適切に多重化するキャッシュデシジョンポリシの提案とその評価を行う.

    CiNii

  • An Intelligent Hybrid MAC With Traffic-Differentiation-Based QoS for Wireless Sensor Networks

    Mohammad Arifuzzaman, Mitsuji Matsumoto, Takuro Sato

    IEEE SENSORS JOURNAL   13 ( 6 ) 2391 - 2399  2013年06月  [査読有り]

     概要を見る

    In this paper, we present the Intelligent Hybrid MAC (IH-MAC), a novel low power with quality of service guaranteed medium access control protocol for wireless sensor networks (WSNs). The IH-MAC achieves high energy efficiency under wide range of traffic load. It ensures shorter latency to critical and delay-sensitive packets. The IH-MAC protocol achieves high channel utilization during high traffic load without compromising energy efficiency. The IH-MAC does it by using the strength of CSMA and TDMA approach with intelligence. The novel idea behind the IH-MAC is that it uses both the broadcast scheduling and link scheduling. Depending on the network loads, the IH-MAC protocol dynamically switches from broadcast scheduling to link scheduling and vice versa in order to achieve better efficiency. The scheduling is done in the IH-MAC with a novel decentralized approach where the nodes locally use the clock arithmetic to find the time slot, allocated for it. Furthermore, the IH-MAC uses Request-To-Send, Clear-To-send handshakes with methods for adapting the transmit power to the minimum level necessary to reach the intended neighbor. Thus, the IH-MAC reduces energy consumption by suitably varying the transmit power. The IH-MAC also uses the concept of parallel transmission that further reduces delay. The analytical and simulation results corroborate the theoretical idea, and show the efficiency of our proposed protocol.

    DOI

    Scopus

    56
    被引用数
    (Scopus)
  • An Intelligent Hybrid MAC With Traffic-Differentiation-Based QoS for Wireless Sensor Networks

    Mohammad Arifuzzaman, Mitsuji Matsumoto, Takuro Sato

    IEEE SENSORS JOURNAL   13 ( 6 ) 2391 - 2399  2013年06月  [査読有り]

     概要を見る

    In this paper, we present the Intelligent Hybrid MAC (IH-MAC), a novel low power with quality of service guaranteed medium access control protocol for wireless sensor networks (WSNs). The IH-MAC achieves high energy efficiency under wide range of traffic load. It ensures shorter latency to critical and delay-sensitive packets. The IH-MAC protocol achieves high channel utilization during high traffic load without compromising energy efficiency. The IH-MAC does it by using the strength of CSMA and TDMA approach with intelligence. The novel idea behind the IH-MAC is that it uses both the broadcast scheduling and link scheduling. Depending on the network loads, the IH-MAC protocol dynamically switches from broadcast scheduling to link scheduling and vice versa in order to achieve better efficiency. The scheduling is done in the IH-MAC with a novel decentralized approach where the nodes locally use the clock arithmetic to find the time slot, allocated for it. Furthermore, the IH-MAC uses Request-To-Send, Clear-To-send handshakes with methods for adapting the transmit power to the minimum level necessary to reach the intended neighbor. Thus, the IH-MAC reduces energy consumption by suitably varying the transmit power. The IH-MAC also uses the concept of parallel transmission that further reduces delay. The analytical and simulation results corroborate the theoretical idea, and show the efficiency of our proposed protocol.

    DOI

    Scopus

    56
    被引用数
    (Scopus)
  • スマートグリッド分野における無線センサネットワークのデータ融合技術に関する研究(移動通信ワークショップ)

    周 巍, 呉 昊, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   112 ( 443 ) 163 - 169  2013年02月

     概要を見る

    近年、無線技術の進歩に伴い無線センサ端末の小型化,低価格化および標準化の進展が著しいである.スマートグリッド分野において、膨大な数の住宅やビルに対して、情報を収集する無線センサネットワーク技術が注目を集めている.私は各家庭やビルなどにある環境清報を長期間の観測及び監視をするため、大規模なセンサネットワークに対応できるデータの処理方法が必要だと考えている.スマートグリッド分野における、センサ収集データの処理方法による高精度のデータを取得し、最適な省エネルギー手法やデマンドレスポンス手法が生み出すことができる.本提案は、スマートグリットのHEMSとBEMS分野における、センサ収集データの処理方法に注目し、従来の処理方法より高い精度なデータ処理を提案し、提案する処理方法で評価を行い、従来型のデータ処理方法より優れた事が分かった.

    CiNii

  • WSNを用いた自動灌漑管理システムの応用研究(移動通信ワークショップ)

    呉 昊, Paul Anup Kumar, 周 巍, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   112 ( 443 ) 157 - 161  2013年02月

     概要を見る

    過去、日本の農業の70%以上を占めしていた里山は、天然資源の使用変化と社会問題により相次いて消失した。里山の復興に目を置き、筆者は農業におけるワイヤレス・センサ・ネットワークを用いた温度、湿度の監視と制御を提案する。本稿では、効果的なデータ収集や省エネーのクラスタリングスキームを確保できる方法について研究を行った結果、センサノートが定期的なデータ収集により良く対応できることを明らかにした。その結論によって、人口の減少に対応し里山の生産性と効率性を向上させることが可能になった。

    CiNii

  • 災害時における移動性の情報共有システムの開発 : 一般講演(試作・実用化の報告)(移動通信ワークショップ)

    沈 子捷, Lopez Jairo Eduardo, 余 娜, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   112 ( 443 ) 151 - 155  2013年02月

     概要を見る

    本稿では、情報通信技術(ICT)のアプローチの近代的な概念を使用して情報共有システムを提案する。濃縮された首都圏の災害は、人間の生命や財産に深刻な被害の重大な損失を引き起こす。災害が発生すると被害地域外の救助者は避難所の場所はそれほど頻繁に提供されるより集約された情報を必要とするなどのサービスを提供しながら、被害者は、リアルタイムで離散的事件の情報を受信する必要があります。スマートフォンの需要は驚異的な成長、私たちの災害管理システムのウェブサービスは、スマートフォンに提供することができたので。さらに救助を評価するために、モバイルユーザーがワイヤレス測位技術を通じて現在位置を取得し、システムに災害関連情報をアップロードすることもできますが、この論文では、情報共有システムの設計について説明し、損傷領域外の救助者かウェブサイト上でこれらのデータを確認する操作。

    CiNii

  • Performance Evaluation of WLAN under Impulsive Electromagnetic Interference in Substation

    Zhenyu Zhou, Jun Wu, Muhammad Tariq, Zhiheng Liu, Takuro Sato

    2013 INTERNATIONAL CONFERENCE ON ICT CONVERGENCE (ICTC 2013): FUTURE CREATIVE CONVERGENCE TECHNOLOGIES FOR NEW ICT ECOSYSTEMS     171 - 176  2013年  [査読有り]

     概要を見る

    Wireless communication technologies bring numerous bene. ts for smart grid applications including lower cost, more. exibility, easier installation, etc. In this paper, the performance of wireless local area network (WLAN) under impulse electromagnetic interference (EMI) in a substation is evaluated. Simulation results have demonstrated that the impulsive EMI causes more severe degradations compared with additive white Gaussian noise (AWGN), especially when the signal to interference plus noise ratio (SINR) is high. Although multiple-antenna based diversity schemes achieve better performance than the single-antenna scheme, the diversity gain is not sufficient to compensate for the performance loss caused by the impulsive EMI. Therefore, how to mitigate the impulsive EMI is essential for deploying WLAN systems in a substation. This paper also summarized conventional interference mitigation techniques, and their adaptability to the impulsive EMI. The analysis provides an insight to future research.

  • A cluster-based consensus algorithm in a wireless sensor network

    Yanwei Li, Zhenyu Zhou, Takuro Sato

    International Journal of Distributed Sensor Networks   2013  2013年

     概要を見る

    In this paper, we propose an average connectivity degree cluster (ACDC) scheme gossip algorithm to improve the convergence speed and the accuracy of the consensus, when a common decision is needed for a certain phenomenon in a distributed network. We analyze the effects of the initial value, the network topology (regular and irregular), and the number of clusters on the algorithm convergence rate as well as the accuracy of the value when reaching consensus. A utility function is developed based on two parameters, iteration and relative error, to help the network designers make an optimal decision based on their requirements. An irregular sensor model which is based on the degree of irregular (DOI) radius is introduced to evaluate the robustness of the algorithm. The simulation results demonstrate that for any initial value and network topology, the proposed ACDC gossip algorithm can yield results that are 50% closer to the real average value than the referenced standard gossip and grid cluster gossip algorithms. With different DOI values, our ACDC gossip algorithm can still reach lower relative error compared with other gossip algorithms, which demonstrates that our algorithm is robust enough to be executed in the network. © 2013 Yanwei Li et al.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • A cluster-based consensus algorithm in a wireless sensor network

    Yanwei Li, Zhenyu Zhou, Takuro Sato

    International Journal of Distributed Sensor Networks   2013  2013年

     概要を見る

    In this paper, we propose an average connectivity degree cluster (ACDC) scheme gossip algorithm to improve the convergence speed and the accuracy of the consensus, when a common decision is needed for a certain phenomenon in a distributed network. We analyze the effects of the initial value, the network topology (regular and irregular), and the number of clusters on the algorithm convergence rate as well as the accuracy of the value when reaching consensus. A utility function is developed based on two parameters, iteration and relative error, to help the network designers make an optimal decision based on their requirements. An irregular sensor model which is based on the degree of irregular (DOI) radius is introduced to evaluate the robustness of the algorithm. The simulation results demonstrate that for any initial value and network topology, the proposed ACDC gossip algorithm can yield results that are 50% closer to the real average value than the referenced standard gossip and grid cluster gossip algorithms. With different DOI values, our ACDC gossip algorithm can still reach lower relative error compared with other gossip algorithms, which demonstrates that our algorithm is robust enough to be executed in the network. © 2013 Yanwei Li et al.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Game Theory based Hybrid Access for Macrocell-edge Users in a Macro-Femto Network

    Yanwei Li, Zhenyu Zhou, Nam Nguyen, Takuro Sato

    2013 IEEE 77TH VEHICULAR TECHNOLOGY CONFERENCE (VTC SPRING)    2013年  [査読有り]

     概要を見る

    The extensive deployment of femtocells introduces co-channel interference to the macro cell-edge users (MCEUs), which degrades the throughput improvement of the total network. In this paper, we consider the scenario in which the femtocell base station (FBS) allows the hybrid access of MCEUs on the condition that the MCEUs rent the power resource from it. However, the FBS is power limited. If almost all of its power is used to serve the MCEUs and its original femtocell users (FUEs), when newly authoritized FUEs are switched on, there will be little power left to serve these newly authoritized FUEs. In this situation, the FBS can select one MCEU as a relay to coordinate its information transmission to the FUE. To reward the cooperation of the MCEUs, the FBS will agree to support the service of MCEUs without charging. Stackelberg game is used to find the optimal power and price value for this procedure. An MCEU relay selection criterion is proposed for the FBS. The optimal power that the MCEU can obtain from the FBS and the power that the MCEU can obtain from the FBS and the power that the MCEU can share with the FUEs are obtained. The simulation results show that the throughputs of both the FUEs and the MCEUs are improved.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Data Collection Method for Mobile Sensor Networks based on the Theory of Thermal Fields

    Martin Macuha, Muhammad Tariq, Takuro Sato

    Journal Sensors in MDPI    2012年12月

  • ストレステスト3態

    佐藤 拓朗

    シミュレーション   31 ( 2 ) 75 - 82  2012年06月

    CiNii

  • An Adaptive Blind Single Antenna Interference Cancellation Algorithm for 4G LTE Systems

    Zhenyu Zhou, Yi Jiang, Muhammad Tariq, Yanwei Li, Takuro Sato

    2012 IEEE 14TH INTERNATIONAL CONFERENCE ON HIGH PERFORMANCE COMPUTING AND COMMUNICATIONS & 2012 IEEE 9TH INTERNATIONAL CONFERENCE ON EMBEDDED SOFTWARE AND SYSTEMS (HPCC-ICESS)     1162 - 1166  2012年

     概要を見る

    In previous works, a blind single antenna interference cancellation (SAIC) algorithm named least mean squareblind joint maximum likelihood sequence estimation (LMS-BJMLSE) has been proposed for OFDM systems. It is blind with respect to interference and is able to cancel interference by only one receive antenna. However, LMS-BJMLSE requires a long training sequence (TS) for channel estimation, which greatly reduces the transmission efficiency. Furthermore, since TS is not available in 4G LTE systems, LMS-BJMLSE can not be applied directly. In this paper, in order to solve this problem, a SINR and symbol position weight adaptive algorithm is proposed, and named as adaptive LMS-BJMLSE (ALMS-BJMLSE). For each slot, ALMS-BJMLSE dynamically decides the number of antennas used for interference cancellation and adjusts the step size, based on estimated SINR conditions and symbol position weight. Simulation results demonstrate that ALMS-BJMLSE achieves a much better balance between performance and transmission efficiency compared to the conventional LMS-BJMLSE algorithm, and can be applied for 4G LTE systems.

    DOI

    Scopus

  • 基地局間連携 MIMO における帯域保証リソース割当方式に関する一考察

    大西 健太, 爲末 和彦, 佐藤 拓朗

    日本シミュレーション学会論文誌   4 ( 3 ) 107 - 115  2012年

     概要を見る

    We propose a resource allocation method which guarantees a throughput of each mobile station (MS) in a Base Station (BS) cooperated MIMO. A previously proposed method for guaranteeing MS throughputs allocates resource to MSs which can not guarantee throughput with a bad channel quality. Our method excludes MSs with a bad channel quality and allocates resource to the other MSs with a good channel quality. The simulation result showed our method guaranteed more MSs' throughput and achieved a higher system throughput than the previous method.

    CiNii

  • 無線端末を用いた視覚障害者向け衝突回避システム(無線通信のための信号処理及び一般)

    蒋 〓贇, 佐藤 拓朗

    電子情報通信学会技術研究報告. SIP, 信号処理   111 ( 403 ) 139 - 141  2012年01月

    CiNii

  • 無線端末を用いた視覚障害者向け衝突回避システム(無線通信のための信号処理及び一般)

    蒋 〓贇, 佐藤 拓朗

    電子情報通信学会技術研究報告. RCS, 無線通信システム   111 ( 404 ) 139 - 141  2012年01月

    CiNii

  • 無線端末を用いた視覚障害者向け衝突回避システム

    蒋 〓贇, 佐藤 拓朗

    電子情報通信学会技術研究報告. SIP, 信号処理 : IEICE technical report   111 ( 403 ) 139 - 141  2012年01月

    CiNii

  • Inter-Signal Interference Cancellation Filter for Four-Element Single Sideband Modulation

    Yi Jiang, Zhenyu Zhou, Masahiko Nanri, Gen-Ichiro Ohta, Takuro Sato

    2012 IEEE 75TH VEHICULAR TECHNOLOGY CONFERENCE (VTC SPRING)    2012年  [査読有り]

     概要を見る

    This paper aims at improving the demodulation performances of Four-element Single Sideband signals by proposing a new receiver structure involving an Inter-Signal Interference cancellation filter. The filter makes use of the estimated symbols generated by the receiver to approximate the interference between multiplexed signals inherent to the use of low complexity Hilbert Transform filters at the transmitter. Simulation results show that the new receiver structure performs better than the one formerly proposed in early works on this topic.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Smart Grid Standards for Home and Building Automation

    M. Tariq, Z. Zhou, J. Wu, M. Macuha, T. Sato

    2012 IEEE INTERNATIONAL CONFERENCE ON POWER SYSTEM TECHNOLOGY (POWERCON)    2012年  [査読有り]

     概要を見る

    The involvement of smart grid in home and building automation systems has led to the development of diverse standards for interoperable products to control appliances, lighting, energy management and security. Smart grid enables a user to control the energy usage according to the price and demand. These standards have been developed in parallel by different organizations, which are either open or proprietary. It is necessary to arrange these standards in such a way that it is easier for potential readers to easily understand and select a suitable standard according to their functionalities without going into the depth of each standard. In this paper, we review the main smart grid standards proposed by different organizations for home and building automation in terms of different function fields. In addition, we evaluate the scope of interoperability, benefits and drawbacks of the standard.

    DOI

    Scopus

    22
    被引用数
    (Scopus)
  • An Adaptive Blind Single Antenna Interference Cancellation Algorithm for 4G LTE Systems

    Zhenyu Zhou, Yi Jiang, Muhammad Tariq, Yanwei Li, Takuro Sato

    2012 IEEE 14TH INTERNATIONAL CONFERENCE ON HIGH PERFORMANCE COMPUTING AND COMMUNICATIONS & 2012 IEEE 9TH INTERNATIONAL CONFERENCE ON EMBEDDED SOFTWARE AND SYSTEMS (HPCC-ICESS)     1162 - 1166  2012年  [査読有り]

     概要を見る

    In previous works, a blind single antenna interference cancellation (SAIC) algorithm named least mean squareblind joint maximum likelihood sequence estimation (LMS-BJMLSE) has been proposed for OFDM systems. It is blind with respect to interference and is able to cancel interference by only one receive antenna. However, LMS-BJMLSE requires a long training sequence (TS) for channel estimation, which greatly reduces the transmission efficiency. Furthermore, since TS is not available in 4G LTE systems, LMS-BJMLSE can not be applied directly. In this paper, in order to solve this problem, a SINR and symbol position weight adaptive algorithm is proposed, and named as adaptive LMS-BJMLSE (ALMS-BJMLSE). For each slot, ALMS-BJMLSE dynamically decides the number of antennas used for interference cancellation and adjusts the step size, based on estimated SINR conditions and symbol position weight. Simulation results demonstrate that ALMS-BJMLSE achieves a much better balance between performance and transmission efficiency compared to the conventional LMS-BJMLSE algorithm, and can be applied for 4G LTE systems.

    DOI

    Scopus

  • Power Dissipation Analysis of IEEE 802.15.4 Distributed Multi-Hop Wireless Sensor Networks

    Muhammad Tariq, Zhenyu Zhou, Yong-Jin Park, Takuro Sato

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E94A ( 11 ) 2279 - 2286  2011年11月  [査読有り]

     概要を見る

    The involvement of IEEE 802.15.4 Wireless Sensor Networks (WSNs) in diverse applications has made the realistic analysis of sensor power dissipation in distributed network environments an essential research issue. In this paper, we propose and thoroughly analyze a power dissipation model for Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) based IEEE 802.15.4 distributed multi-hop WSNs. Our model takes the loss rate of frames, neighbor sensors density in communication range of a sensor, number of hops, distance of source to the sink, and density of the network into account. We evaluate the impact of these factors on overall power dissipation. We also perform comprehensive analysis of overheads caused by message routing through multi-hop distributed networks. We validate our proposed model through Monte Carlo simulations. Results show that our power dissipation model is more realistic compared to other proposed models in terms of accuracy and multiplicity of the environments.

    DOI

    Scopus

  • 複数基地局間における帯域保証動的チャネル割当方式(無線通信技術)

    大西 健太, 爲末 和彦, 佐藤 拓朗

    電子情報通信学会論文誌. B, 通信   94 ( 11 ) 1470 - 1480  2011年11月

     概要を見る

    本論文は,複数基地局環境において,個々の端末のスループットを保証可能な基地局制御装置(RNC:Radio Network Controller)を用いた集約的な動的チャネル割当方式(DCA:Dynamic Channel Allocation)について提案する.これまで複数基地局環境において提案されたDCAとしては,個別の端末のスループットを考慮せずにシステム全体の端末のスループットの和を最大化する方式や,ある大きさ以上の基地局間干渉波を抑止する条件のもとでシステム全体の端末のスループットを最大化する方式はあったが,個々の端末のスループットを保証した上でシステム全体における端末のスループットの和を最大化するようなDCAの方式は提案されていなかった.本論文では,提案方式についてシミュレーションを実施し,あらかじめ設定したスループットを保証するチャネル割当が実現可能なことを示す.また従来方式によるシミュレーション結果と比較を行い,提案方式の有効性を示す.

    CiNii

  • 複数基地局間における帯域保証動的チャネル割り当て方式

    西 健太, 爲末, 和彦, 佐藤 拓朗

    IEICE Trans. Communication   pp.Vol.J94-B,No.11 ( 11 )  2011年11月

    J-GLOBAL

  • Power Dissipation Analysis of IEEE 802.15.4 Distributed Multi-Hop Wireless Sensor Networks

    Muhammad Tariq, Zhenyu Zhou, Yong-Jin Park, Takuro Sato

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E94A ( 11 ) 2279 - 2286  2011年11月  [査読有り]

     概要を見る

    The involvement of IEEE 802.15.4 Wireless Sensor Networks (WSNs) in diverse applications has made the realistic analysis of sensor power dissipation in distributed network environments an essential research issue. In this paper, we propose and thoroughly analyze a power dissipation model for Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) based IEEE 802.15.4 distributed multi-hop WSNs. Our model takes the loss rate of frames, neighbor sensors density in communication range of a sensor, number of hops, distance of source to the sink, and density of the network into account. We evaluate the impact of these factors on overall power dissipation. We also perform comprehensive analysis of overheads caused by message routing through multi-hop distributed networks. We validate our proposed model through Monte Carlo simulations. Results show that our power dissipation model is more realistic compared to other proposed models in terms of accuracy and multiplicity of the environments.

    DOI

    Scopus

  • A Realistic Communication Model for Distributed Error-Prone Wireless Sensor Networks

    Muhammad Tariq, Martin Macuha, Yong-Jin Park, Takuro Sato

    IEICE TRANSACTIONS ON COMMUNICATIONS   E94B ( 10 ) 2805 - 2816  2011年10月  [査読有り]

     概要を見る

    With Wireless Sensor Networks (WSNs) involving in diverse applications, the realistic analysis of energy consumption of a sensor node in an error-prone network environment is emerging as an elementary research issue. In this paper, we introduce a Distributed Communication Model (DCM) that can accurately determine the energy consumption through data communication from source to destination in error-prone network environments. The energy consumption is affected with the quality of link, which is characterized by symmetry, directivity, instability, and irregularity of the communication range of a sensor node. Due to weak communication links, significant packet loss occurs that affects the overall energy consumption. While other models unable to determine energy consumption due to lossy links in error-prone and unstable network environments, DCM can accurately estimate the energy consumption in such situations. We also perform comprehensive analysis of overheads caused by data propagation through multi-hop distributed networks. We validate DCM through both simulations and experiments using MICAz motes. Similarity of the results from energy consumption analysis with both simulations and experimentations shows that DCM is realistic, compared to other models in terms of accuracy and diversity of the environments.

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • Evaluating Gossip Algorithm based on Energy Constrained Best Linear Unbiased Estimation in Wireless Sensor Network

    Yanwei Li, Muhammad Tariq, Anup Kumar Paul, Martin Macuha, Takuro Sato

    International Conference on Modeling and Simulation Technology(JSST 2011)    2011年10月

  • Range free angle calculation (rfac) based sensor localization in wireless sensor networks

    Anup Kumar Paul, Muhammad Tariq, Li Yanwei, Takuro Sato

    International Conference on Modeling and Simulation Technology, JSST-2011    2011年10月

  • B-5-52 フェムトセルの干渉電力制御方式(B-5. 無線通信システムA(移動通信),一般セッション)

    小木曽 充彬, 南里 将彦, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2011 ( 1 ) 431 - 431  2011年08月

    CiNii

  • B-1-214 LTEにおける指向性アンテナ制御方式(B-1. アンテナ・伝播C(アンテナシステム),一般セッション)

    桐 貴文, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2011 ( 1 ) 214 - 214  2011年08月

    CiNii

  • B-9-7 ライフスタイルと電力消費のマルコフモデル化(B-9. 電子通信エネルギー技術,一般セッション)

    周 麒, 曽根高 則義, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2011 ( 2 ) 210 - 210  2011年08月

    CiNii

  • Data Collection Method for Mobile Sensor Networks Based on the Theory of Thermal Fields

    Martin Macuha, Muhammad Tariq, Takuro Sato

    SENSORS   11 ( 7 ) 7188 - 7203  2011年07月  [査読有り]

     概要を見る

    Many sensor applications are aimed for mobile objects, where conventional routing approaches of data delivery might fail. Such applications are habitat monitoring, human probes or vehicular sensing systems. This paper targets such applications and proposes lightweight proactive distributed data collection scheme for Mobile Sensor Networks (MSN) based on the theory of thermal fields. By proper mapping, we create distribution function which allows considering characteristics of a sensor node. We show the functionality of our proposed forwarding method when adapted to the energy of sensor node. We also propose enhancement in order to maximize lifetime of the sensor nodes. We thoroughly evaluate proposed solution and discuss the tradeoffs.

    DOI

    Scopus

    7
    被引用数
    (Scopus)
  • Data Collection Method for Mobile Sensor Networks Based on the Theory of Thermal Fields

    Martin Macuha, Muhammad Tariq, Takuro Sato

    SENSORS   11 ( 7 ) 7188 - 7203  2011年07月  [査読有り]

     概要を見る

    Many sensor applications are aimed for mobile objects, where conventional routing approaches of data delivery might fail. Such applications are habitat monitoring, human probes or vehicular sensing systems. This paper targets such applications and proposes lightweight proactive distributed data collection scheme for Mobile Sensor Networks (MSN) based on the theory of thermal fields. By proper mapping, we create distribution function which allows considering characteristics of a sensor node. We show the functionality of our proposed forwarding method when adapted to the energy of sensor node. We also propose enhancement in order to maximize lifetime of the sensor nodes. We thoroughly evaluate proposed solution and discuss the tradeoffs.

    DOI

    Scopus

    7
    被引用数
    (Scopus)
  • Error Probability Bounds Analysis of JMLSE Based Interference Cancellation Algorithms for MQAM-OFDM Systems

    Zhenyu Zhou, Takuro Sato

    IEICE TRANSACTIONS ON COMMUNICATIONS   E94B ( 7 ) 2032 - 2042  2011年07月  [査読有り]

     概要を見る

    Due to the reuse factor reduction, the same frequencies are reused in adjacent neighboring cells, which causes an attendant increase in co-channel interference (CCI). CCI has already become the limiting factor in the performance of orthogonal frequency division multiplexing (OFDM) based cellular systems. Joint maximum likelihood sequence estimation (JMLSE) based interference cancellation algorithms have been under intense research. However, despite the fact that the error probability of JMLSE is critical for analyzing the performance, to the best of our knowledge, the mathematical expression has not been derived for MQAM-OFDM yet. Direct computation of the error probability involves integrating a multi-dimensional Gaussian distribution that has no closed-form solution. Therefore, an alternative way is to upper and lower bound the error probability with computable quantities. In this paper, firstly, both the upper and the conventional lower error probability bounds of JMLSE are derived for MQAM-OFDM systems based on a genie-aided receiver. Secondly, in order to reduce the gap between the conventional lower bound and the simulation results, a tighter lower bound is derived by replacing the genie with a less generous one. Thirdly, those derived error probability bounds are generalized to the receiver diversity scheme. These error probability bounds are important new analytical results that can be used to provide rapid and accurate estimation of the BER performance over any MQAM scheme and an arbitrary number of interferers and receive antennas.

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • Data Collection Method for Mobile Sensor Networks Based on the Theory of Thermal Fields

    Martin Macuha, Muhammad Tariq, Takuro Sato

    SENSORS   11 ( 7 ) 7188 - 7203  2011年07月  [査読有り]

     概要を見る

    Many sensor applications are aimed for mobile objects, where conventional routing approaches of data delivery might fail. Such applications are habitat monitoring, human probes or vehicular sensing systems. This paper targets such applications and proposes lightweight proactive distributed data collection scheme for Mobile Sensor Networks (MSN) based on the theory of thermal fields. By proper mapping, we create distribution function which allows considering characteristics of a sensor node. We show the functionality of our proposed forwarding method when adapted to the energy of sensor node. We also propose enhancement in order to maximize lifetime of the sensor nodes. We thoroughly evaluate proposed solution and discuss the tradeoffs.

    DOI PubMed

    Scopus

    7
    被引用数
    (Scopus)
  • Error probability bounds analysis of JMLSE based interference cancellation algorithms for MQAM-OFDM systems

    Z. Zhou, T. Sato

    IEICE Trans. Commun   vol. E94  2011年07月

  • Training Sequence Reduction for the Least Mean Square-Blind Joint Maximum Likelihood Sequence Estimation Co-channel Interference Cancellation Algorithm in OFDM Systems

    Zhenyu Zhou, Takuro Sato

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E94A ( 5 ) 1173 - 1183  2011年05月  [査読有り]

     概要を見る

    Due to the reuse factor reduction, the attendant increase in co-channel interference (CCI) becomes the limiting factor in the performance of the orthogonal frequency division multiplexing (OFDM) based cellular systems. In the previous work, we proposed the least mean square-blind joint maximum likelihood sequence estimation (LMS-BJMLSE) algorithm, which is effective for CCI cancellation in OFDM systems with only one receive antenna. However, LMS-BJMLSE requires a long training sequence (TS) for channel estimation, which reduces the transmission efficiency. In this paper, we propose a subcarrier identification and interpolation algorithm, in which the subcarriers are divided into groups based on the coherence bandwidth, and the slowest converging subcarrier in each group is identified by exploiting the correlation between the mean-square error (MSE) produced by LMS and the mean-square deviation (MSD) of the desired channel estimate. The identified poor channel estimate is replaced by the interpolation result using the adjacent subcarriers' channel estimates. Simulation results demonstrate that the proposed algorithm can reduce the required training sequence dramatically for both the cases of single interference and dual interference. We also generalize LMS-BJMLSE from single antenna to receiver diversity, which is shown to provide a huge improvement.

    DOI

    Scopus

    3
    被引用数
    (Scopus)
  • Training sequence reduction for the least mean square-blind joint maximum likelihood sequence estimation co-channel interference cancellation algorithm in OFDM systems

    Z. Zhou, T. Sato

    IEICE Trans. Fundamentals   vol. E94-A, No. 5  2011年05月

  • 多次元移動通信網研究委員会(研究委員会紹介)

    佐藤 拓朗, 田村 裕, 山本 潮, 伊藤 建一

    シミュレーション   30 ( 1 ) 46 - 48  2011年04月

    CiNii

  • BK-1-2 最適電力供給運行ネットワークシステムの検討(BK-1.新しい時代に向けて-情報通信ネットワークと電気自動車-,ソサイエティ特別企画,ソサイエティ企画)

    李 大鵬, 佐藤 拓朗

    電子情報通信学会総合大会講演論文集   2011 ( 1 ) "SS - 3"-"SS-4"  2011年02月

    CiNii

  • BK-1-1 プロービング情報を用いた交通渋滞回避システム(BK-1.新しい時代に向けて-情報通信ネットワークと電気自動車-,ソサイエティ特別企画,ソサイエティ企画)

    胡 愛嫻, 佐藤 拓朗

    電子情報通信学会総合大会講演論文集   2011 ( 1 ) "SS - 1"-"SS-2"  2011年02月

    CiNii

  • B-15-12 スマートフォンにおける不正アクセスに対する監視機能(B-15.モバイルマルチメデイア通信,一般セッション)

    佐藤 光正, 佐藤 拓朗

    電子情報通信学会総合大会講演論文集   2011 ( 1 ) 585 - 585  2011年02月

    CiNii

  • AS-4-3 無線端末を用いた視聴覚障害者向け衝突回避システム(AS-4.安全・安心な生活のための情報通信ネットワーク,シンポジウムセッション)

    蒋 〓贇, 佐藤 拓朗

    電子情報通信学会総合大会講演論文集   2011   "S - 57"-"S-58"  2011年02月

    CiNii

  • Performance Evaluation of A Blind Single Antenna Interference Cancellation Algorithm for OFDM Systems with Insufficient Training Sequence

    Zhenyu Zhou, Muhammad Tariq, Yi Jiang, Nam Hoai Nguyen, Takuro Sato

    2011 IEEE VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL)    2011年  [査読有り]

     概要を見る

    In the previous work, a single antenna interference cancellation (SAIC) algorithm named least mean square-blind joint maximum likelihood sequence estimation (LMS-BJMLSE) has been proposed. However, LMS-BJMLSE requires a long training sequence (TS) for channel estimation, which reduces the transmission efficiency. In another work, in order to solve this problem, a subcarrier identification and interpolation algorithm was proposed, in which the slowly converging subcarriers are identified by exploiting the correlation between the mean-square error (MSE) produced by LMS and the mean-square deviation (MSD) of the desired channel estimate. However, this correlation relationship was only found based on simulation results and no clear mathematical proof was given. The performance of the algorithm was only evaluated for the case of single interference. In this paper, the mathematical proof of the correlation relationship between MSE and MSD is given. Furthermore, we generalize LMS-BJMLSE from single antenna to receiver diversity, which is shown to provide a huge improvement over single antenna. The performance of LMS-BJMLSE is also evaluated for the case of dual interference.

  • RLS for Link Trigger in Handover across Heterogeneous Wireless Networks

    Nam Hoai Nguyen, Zhenyu Zhou, Takuro Sato

    2011 IEEE VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL)    2011年  [査読有り]

     概要を見る

    The wireless communication system is evolving towards a ubiquitous wireless network in which multiple-radio devices can roam anytime and anywhere across different access networks. Minimal latency and low packet loss ratio during handover (HO) are the indispensable requirements to reduce service disruption and support real-time services. However, minimizing service disruption is a challenging issue to multiple access networks since HO latency is much higher than that of homogeneous networks. Link layer trigger or layer 2 trigger has been proposed to address this issue. Nevertheless, the precise timing and definitive criteria for initiating L2 trigger which can greatly affect the handover performance is not specified. This paper considers the issue of how to timely initiate handover decision from the link layer by using adaptive filtering algorithm to predict forthcoming received signal. Particularly, we propose Recursive Least Squares (RLS) as the predictive method for layer 2 triggering and compare its performance with various conventional filtering techniques. A simulation in which the proposed predictive algorithm is implemented to a handover scenario from Wi-Fi to WIMAX is also presented. Our numerical analysis and simulation results show that the proposed algorithm can achieve better performance than that of the other algorithms and can be used to enhance the handover performance in heterogeneous wireless networks.

  • Performance Evaluation of Four Orthogonal Single Sideband Elements Modulation Scheme in Multi-Carrier Transmission Systems

    Yi Jiang, Zhenyu Zhou, Masahiko Nanri, Gen-Ichiro Ohta, Takuro Sato

    2011 IEEE VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL)    2011年  [査読有り]

     概要を見る

    This paper proposes a study of performances of the Orthogonal Four Single Sideband elements modulation previously proposed by Ohta [1]. Realistic parameters such as receiver noise and various channel effects are introduced in the derivation of the modulation. Transmission of two QPSK signals multiplexed in one 4-SSB (Single Sideband) signal over OFDM (Orthogonal frequency-division multiplexing) is considered and a demodulation process exploiting a turbo equalizer is presented. Computer simulations are used to verify the performances of the proposed modulation scheme. Results show that 4-SSB QPSK signal over OFDM can achieve performances close to QPSK-OFDM scheme while carrying twice more information, provided perfect channel equalization. However, we also show that in a non-ideal equalization case, performances of 4-SSB QPSK OFDM become highly sensitive to channel effects.

  • Utilizing Femtocells for Peer-to-Peer File Sharing in Cellular Networks

    Martin Macuha, Yangyang Li, Takuro Sato

    2011 IEEE 22ND INTERNATIONAL SYMPOSIUM ON PERSONAL INDOOR AND MOBILE RADIO COMMUNICATIONS (PIMRC)     21 - 25  2011年  [査読有り]

     概要を見る

    Peer-to-Peer file sharing, computing and communication services are widely used by internet community and thoroughly studied by academia. However, main utilization of such services is in the wired networks due to several significant issues in the wireless world like connectivity, bandwidth, battery, unwillingness of cellular operators, etc. In the recent years, offering femtocell access points to subscribers became very promising business model for cellular operator. It also opens space for a variety of new services at the users premises. In this paper, we propose novel architecture for mobile peer-to-peer file sharing based on the femtocell deployment and describe a role of the femtocell in such scenario. We also describe traditional architecture and previously proposed solutions for mobile P2P. We evaluate these approaches and clearly show that the femtocell plays significant role and moves mobile P2P services into reality. We also discuss several current issues which can be easily solved by this architecture.

    DOI

    Scopus

  • RLS for link trigger in handover across heterogeneous wireless networks

    Nam Hoai Nguyen, Zhenyu Zhou, Takuro Sato

    IEEE Vehicular Technology Conference    2011年

     概要を見る

    The wireless communication system is evolving towards a ubiquitous wireless network in which multiple-radio devices can roam anytime and anywhere across different access networks. Minimal latency and low packet loss ratio during handover (HO) are the indispensable requirements to reduce service disruption and support real-time services. However, minimizing service disruption is a challenging issue to multiple access networks since HO latency is much higher than that of homogeneous networks. Link layer trigger or layer 2 trigger has been proposed to address this issue. Nevertheless, the precise timing and denitive criteria for initiating L2 trigger which can greatly affect the handover performance is not specified. This paper considers the issue of how to timely initiate handover decision from the link layer by using adaptive filtering algorithm to predict forthcoming received signal. Particularly, we propose Recursive Least Squares (RLS) as the predictive method for layer 2 triggering and compare its performance with various conventional filtering techniques. A simulation in which the proposed predictive algorithm is implemented to a handover scenario from Wi-Fi to WIMAX is also presented. Our numerical analysis and simulation results show that the proposed algorithm can achieve better performance than that of the other algorithms and can be used to enhance the handover performance in heterogeneous wireless networks. © 2011 IEEE.

    DOI

    Scopus

  • Performance evaluation of a blind single antenna interference cancellation algorithm for OFDM systems with insufficient training sequence

    Zhenyu Zhou, Muhammad Tariq, Yi Jiang, Nam Hoai Nguyen, Takuro Sato

    IEEE Vehicular Technology Conference    2011年

     概要を見る

    In the previous work, a single antenna interference cancellation (SAIC) algorithm named least mean square-blind joint maximum likelihood sequence estimation (LMS-BJMLSE) has been proposed. However, LMS-BJMLSE requires a long training sequence (TS) for channel estimation, which reduces the transmission efficiency. In another work, in order to solve this problem, a subcarrier identification and interpolation algorithm was proposed, in which the slowly converging subcarriers are identified by exploiting the correlation between the mean-square error (MSE) produced by LMS and the mean-square deviation (MSD) of the desired channel estimate. However, this correlation relationship was only found based on simulation results and no clear mathematical proof was given. The performance of the algorithm was only evaluated for the case of single interference. In this paper, the mathematical proof of the correlation relationship between MSE and MSD is given. Furthermore, we generalize LMS-BJMLSE from single antenna to receiver diversity, which is shown to provide a huge improvement over single antenna. The performance of LMS-BJMLSE is also evaluated for the case of dual interference. © 2011 IEEE.

    DOI

    Scopus

    3
    被引用数
    (Scopus)
  • Performance Evaluation of Four Orthogonal Single Sideband Elements Modulation Scheme in Multi-Carrier Transmission Systems

    Yi Jiang, Zhenyu Zhou, Masahiko Nanri, Gen-Ichiro Ohta, Takuro Sato

    2011 IEEE VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL)    2011年  [査読有り]

     概要を見る

    This paper proposes a study of performances of the Orthogonal Four Single Sideband elements modulation previously proposed by Ohta [1]. Realistic parameters such as receiver noise and various channel effects are introduced in the derivation of the modulation. Transmission of two QPSK signals multiplexed in one 4-SSB (Single Sideband) signal over OFDM (Orthogonal frequency-division multiplexing) is considered and a demodulation process exploiting a turbo equalizer is presented. Computer simulations are used to verify the performances of the proposed modulation scheme. Results show that 4-SSB QPSK signal over OFDM can achieve performances close to QPSK-OFDM scheme while carrying twice more information, provided perfect channel equalization. However, we also show that in a non-ideal equalization case, performances of 4-SSB QPSK OFDM become highly sensitive to channel effects.

    DOI

    Scopus

    5
    被引用数
    (Scopus)
  • Performance Evaluation of the IEEE 802.15.4 Multi-hop Communications in Error-prone Wireless Sensor Networks

    Muhammad Tariq, Martin Macuha, Yong-Jin Park, Takuro Sato

    MOBIWAC 11: PROCEEDINGS OF THE NINTH ACM INTERNATIONAL SYMPOSIUM ON MOBILITY MANAGEMENT AND WIRELESS ACCESS     131 - 135  2011年  [査読有り]

     概要を見る

    Performance evaluation in terms of energy conservation and data reliability of the IEEE 802.15.4 multi-hop communications in error-prone Wireless Sensor Networks (WSNs) is an emerging research issue. In order to accurately evaluate the energy consumption of a sensor node and ultimately the lifetime of WSNs, it is highly desired to thoroughly analyze data reliability through variety of aspects. In this paper, we analyze data reliability in the IEEE 802.15.4 multi-hop communications in error-prone WSNs, by assessing the channel quality using both physical and logical channel quality estimators with different set of parametric values of IEEE 802.15.4 Medium Access Control (MAC) protocol. On the basis of these estimators, we approximate the energy consumption of a sensor node. We also analyze the overheads caused by packet forwarding in the multi-hop WSNs. Simulation results indicate that although physical channel quality estimators are dependent on hardware characteristics, they show better performance in terms of energy consumption and successful data delivery compared to logical channel quality estimators.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • A scheme for disaster recovery in wireless networks with dynamic ad-hoc routing

    Chen, Guowei, Hu, Aixian, Sato, Takuro

    International Telecommunication Union - Proceedings of the 2010 ITU-T Kaleidoscope Academic Conference: Beyond the Internet? Innovations for Future Networks and Services     183 - 188  2010年12月

     概要を見る

    This paper proposes a hybrid network scheme combining ad-hoc networks into cellular networks. The scheme is aimed to help the networks to recover to service as much as possible after a disaster strike, by maintaining the connection between Base Stations (BSs) and nodes via multi-hopping, where if a node cannot connect to a BS directly, it switches its working mode from cellular mode to ad-hoc mode. A location-based routing protocol has been proposed for building a route from the node to the BS. Simulation results shows that even if only a small part of the nodes can directly connect to a BS, most of the nodes can find a route to a BS via multi-hopping. And it is found that it outperforms a previously proposed solution which is via beaconing in terms of resistance to mobility.

    CiNii

  • B-21-3 MANETにおける確率密度関数を用いたノードクラスタ化に関する検討(B-21.アドホックネットワーク,一般セッション)

    樋口 太祐, 曽根高 則義, 佐藤 拓朗, 富永 英義

    電子情報通信学会ソサイエティ大会講演論文集   2010 ( 2 ) 440 - 440  2010年08月

    CiNii

  • A-17-19 最適ルート配送ネットワーク構成の検討(A-17.ITS,一般セッション)

    李 大鵬, 佐藤 拓朗

    電子情報通信学会ソサイエティ大会講演論文集   2010   165 - 165  2010年08月

    CiNii

  • A-4-10 雑音信号を利用し,音声信号に情報を乗せる研究(A-4.信号処理,一般セッション)

    島村 泰輝, 佐藤 拓朗, 富永 英義

    電子情報通信学会ソサイエティ大会講演論文集   2010   79 - 79  2010年08月

    CiNii

  • 1-326 早稲田大学大学院日本規格協会・経済産業省提携講座の進め方と成果(その2) : 「企業ビジネス戦略と国際標準化」((19)国際化時代における工学教育-III,口頭発表論文)

    佐藤 拓朗

    工学・工業教育研究講演会講演論文集   22   466 - 467  2010年08月

    CiNii

  • Handoff with Assistance of Distance for Wireless Relay Networks"

    Guowei Chen, Wipaporn Clayboot, Kenichi Itoh, Takuro Sato

    Transaction of the Japan Society fro Simulation Technology   Vol.29, No.2 ( 2 ) 76 - 82  2010年06月

     概要を見る

    A handoff algorithm with the criterion of linear combination of RSSI (Received Signal Strength Indicator) and distance is proposed. The system model under study is a multi-hop network with two fixed access points, some moving terminal repeaters, and a mobile terminal. The mobile terminal moves from one access point to the other, and makes handoff thru the terminal repeaters to maintain access to service. Simulation is made and the results are compared against the RSSI-only algorithm and the distance-assisted algorithm [2]. It is found that the proposed algorithm achieves lower handoff percentage and outage occurrence.

    DOI CiNii

  • Considering Node Dgree in Anycast Routing in Wireless Ad-Hoc Neyworks"

    Martin Macuha, Takuro Sato

    Transaction of the Japan Society fro Simulation Technology   Vol.29, No.2 ( 2 ) 67 - 75  2010年06月

     概要を見る

    In anycast routing the packet is routed to anyone of the anycast group members. Anycast allows supporting many services and can significantly improve network performance of wireless networks. In this paper, we provide an analysis of anycast routing in mobile ad hoc networks. We also show the correlation between mobility and the probability of connected route in anycast scenario and impact of the node degree density. To evaluate improvement of the network performance we design anycast proactive protocol with two modes. The first routing mode considers only the shortest path routing and another considers also the node degree density through the count of routes to the anycast group member. We also compare the performance with a potential field-based proactive anycast protocol.

    DOI CiNii

  • A Single Antenna Interference Cancellation Algorithm for OFDM Communication"

    Zhenyu ZHOU, Takuro SATO

    IEICE Trans   Vol.J93-B,No.02 ( 2 ) 259 - 268  2010年02月

     概要を見る

    本論文では直交周波数分割多重(OFDM:Orthogonal Frequency Division Multiplexing)システムに対して高速フェージング環境下においても高精度に動作できる逐次型チャネル推定(SCE:Sequential Channel Estimation)と適応同時最大事後確率(AJMAP:Adaptive Joint Maximum A Posterior Probability)を用いた単一アンテナ同一チャネル干渉除去方式を検討したので提案する.本論文で提案したSCE-AJMAPアルゴリズムは,シンボルごとに各基地局のチャネル応答を推定し,受信機側にあるジョイントトレリス生成出力をシンボルごとに更新することにより,高速フェージングによる希望信号と干渉信号が合成された受信信号の振幅変動をより精密に追従できる.本論文では計算器シミュレーションにより,提案したSCE-AJMAP復号器が従来のJMAP復号器に比べて高速フェージング環境における受信機の特性を大きく改善できることを確認した.

    CiNii

  • COGNITIVE UPLINK INTERFERENCE MANAGEMENT IN 4G CELLULAR FEMTOCELLS

    Yang-Yang Li, Elvino S. Sousa

    2010 IEEE 21ST INTERNATIONAL SYMPOSIUM ON PERSONAL INDOOR AND MOBILE RADIO COMMUNICATIONS (PIMRC)     1567 - 1571  2010年  [査読有り]

     概要を見る

    We study a cognitive channel reuse approach for autonomous femtocell deployment in an OFDMA-based cellular network. The objective is to manage the uplink interference from macrocell users to femtocell access points. Macrocell users are normally far away from the base station and may cause strong uplink interference to the close-by femtocells. By cognitive interference recognition, a femtocell access point autonomously reuse the proper channel modes for interference minimization. We propose an opportunistic channel scheduling scheme that determines optimal channel and power allocation to femtocell users. Simulation results show improved uplink performance in terms of the average channel outage probability in femtocells.

  • A Preface to the Special Edition "Advanced Simulation for Multi Dimension Mobile Communication Networks"

    佐藤 拓朗

    日本シミュレーション学会論文誌   2 ( 2 ) 49 - 49  2010年

    DOI CiNii

  • An energy estimation model for mobile sensor networks

    Muhammad Tariq, Martin Macuha, Yong-Jin Park, Takuro Sato

    Proceedings - 4th International Conference on Sensor Technologies and Applications, SENSORCOMM 2010     507 - 512  2010年

     概要を見る

    Mobile sensor networks have received significant attention recently. Mobile sensors are deployed to achieve network load balancing, prolonging network lifetime, and improving network coverage, by monitoring critical areas where manual sensor deployment cannot be performed. To achieve these goals, energy estimation is one of the main constraints and concerns to consider, while deploying mobile sensors in a sensor field. Most of the energy models designed for sensor networks assumed static sensors. In this paper, we propose a comprehensive energy model to estimate the overall energy consumption through power dissipation, for both static and mobile sensors in the potential sensor fields. We calculate the total remaining lifetime of mobile sensor networks from the total power dissipation. By predicting the remaining lifetime of any network in different network scenarios at a given instance of time, an optimum network strategy can be designed for a given application. © 2010 IEEE.

    DOI

    Scopus

    7
    被引用数
    (Scopus)
  • Error Probability Bounds of JMLSE Based Single Antenna Interference Cancellation Algorithms for MQAM-OFDM Systems

    Zhenyu Zhou, Muhammad Tariq, Takuro Sato

    2010 IEEE 72ND VEHICULAR TECHNOLOGY CONFERENCE FALL    2010年  [査読有り]

     概要を見る

    In orthogonal frequency division multiplexing (OFDM) based cellular systems, co-channel interference (CCI) would greatly degrade the bit error rate (BER) performance of cell-border users. Joint maximum likelihood sequence estimation (JMLSE) based single antenna interference cancellation (SAIC) algorithms have been under intense research. In this paper, both the upper and lower error probability bounds for JMLSE are extended to MQAM-OFDM systems based on a genie-aided receiver. The derived upper and lower bounds are valid for any MQAM and an arbitrary number of interferers. A tighter lower bound is derived by replacing the genie with a less generous one. We prove that this new lower bound is much tighter compared to the conventional lower bound.

  • Diffusion Based Self-deployment Algorithm for Mobile Sensor Networks

    Muhammad Tariq, Zhenyu Zhou, Yong-Jin Park, Takuro Sato

    2010 IEEE 72ND VEHICULAR TECHNOLOGY CONFERENCE FALL    2010年  [査読有り]

     概要を見る

    Mobile Sensor Networks (MSN) are used for network load balancing, prolonging network lifetime, and improving network coverage by monitoring critical areas where manual sensor deployment cannot be performed. Addressing the problem of how to achieve maximum network coverage and network uniformity, after deploying sensors in critical areas randomly, is of significant importance recently. In this paper, we design an energy efficient distributed self-deployment algorithm, which is based on the diffusion of mobile sensors in the Region of Interest (ROI). Mobile sensors are diffused from denser sensors area to lesser or uncovered area in ROI, on the basis of localized information. Our algorithm considers ROI with the absence as well as presence of obstacles. Resemblance in the numerical and simulation analysis confirms the concreteness of our algorithm.

  • Training sequence reduction for A blind single antenna interference cancellation algorithm in MQAM-OFDM systems

    Zhenyu Zhou, Takuro Sato

    IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC     36 - 40  2010年

     概要を見る

    In orthogonal frequency division multiplexing (OFDM) based cellular systems, co-channel interference (CCI) from adjacent interfering base stations (BSs) would greatly degrade the bit error rate (BER) performance of cell-border users. In the previous work, a blind single antenna interference cancellation (SAIC) algorithm named least mean square-blind joint maximum likelihood sequence estimation (LMS-BJMLSE) has been proposed. The proposed LMS-BJMLSE algorithm is blind with respect to interfering signals and neither the training sequence (TS) nor pilot signal from interferers is needed. However, the conventional LMS-BJMLSE requires a long training sequence (TS) for channel estimation. In this paper, we propose a TS reduction scheme in which the subcarriers are divided into small groups based on the coherence bandwidth, and the slowest converging subcarrier in each group is identified by exploiting the correlation between the mean-square error (MSE) produced by LMS and the mean-square deviation (MSD) of the desired signal. The identified subcarrier's channel estimate is replaced by the interpolation result using the adjacent subcarriers' channel estimates. Simulation results demonstrate that the proposed algorithm could reduce the required TS length by 80%. ©2010 IEEE.

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • Diffusion based self-deployment algorithm for mobile sensor networks

    Muhammad Tariq, Zhenyu Zhou, Yong-Jin Park, Takuro Sato

    IEEE Vehicular Technology Conference    2010年

     概要を見る

    Mobile Sensor Networks (MSN) are used for network load balancing, prolonging network lifetime, and improving network coverage by monitoring critical areas where manual sensor deployment cannot be performed. Addressing the problem of how to achieve maximum network coverage and network uniformity, after deploying sensors in critical areas randomly, is of significant importance recently. In this paper, we design an energy efficient distributed self-deployment algorithm, which is based on the diffusion of mobile sensors in the Region of Interest (ROI). Mobile sensors are diffused from denser sensors area to lesser or uncovered area in ROI, on the basis of localized information. Our algorithm considers ROI with the absence as well as presence of obstacles. Resemblance in the numerical and simulation analysis confirms the concreteness of our algorithm. ©2010 IEEE.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Study on Adaptive Switching DC offset Compensation Scheme for Direct-Conversion Receiver using SC-FDMA, OFDM modulation"

    Kazuhiko Tamesue, Takuro Sato

    IEICE Transaction B   92 ( 10 ) 1687 - 1695  2009年10月

     概要を見る

    近年,マルチキャリヤ変調方式は高効率データ伝送を実現することから,多くの無線システムに採用されている.一方,受信機の小型化のためには,中間周波数の処理がないダイレクトコンバージョン方式を用いることは重要である.しかし,マルチキャリヤ変調方式は,高速伝送化に伴いDFT(Discrete Fourier Transform)の次数を高めることでPAPR(Peak-to-Average Power Ratio)が大きくなるという問題点がある.このため,LTE(Long Term Evolution)では,下りリンクではOFDM(Orthogonal Frequency Division Multiplexing),上りリンクではSC-FDMA(Single Carrier Frequency Division Multiple Access)方式が採用されている.マルチキャリヤ伝送方式にダイレクトコンバージョン受信機を採用する場合,広帯域化による受信機内部の自己混合によりDCオフセットが発生し,受信感度の劣化が大きな問題となる.本論文では,ダイレクトコンバージョン受信機におけるOFDM,SC-FDMA変調方式の受信信号におけるDCオフセットひずみの軽減方法を提案し,伝送特性を計算機シミュレーションにより評価した結果,従来の単純な平均振幅によるDC除去方式と比較してシンボル誤り率を改善できることを示す.

    CiNii

  • Sampling Frequency O&#64256;set and Residual Carrier Frequency O&#64256;set Compensation method using Pilot symbol for OFDM Systems

    Hiroki Sugimoto, Takuro Sato, Hideyoshi Tominaga

    IEICE Transaction B    2009年10月

  • Study on Adaptive Switching DC offset Compensation Scheme for Direct-Conversion Receiver using SC-FDMA, OFDM modulation

    Kazuhiko Tamesue, Takuro Sato

    IEICE Transaction B   92 ( 10 ) 1687 - 1695  2009年10月

     概要を見る

    近年,マルチキャリヤ変調方式は高効率データ伝送を実現することから,多くの無線システムに採用されている.一方,受信機の小型化のためには,中間周波数の処理がないダイレクトコンバージョン方式を用いることは重要である.しかし,マルチキャリヤ変調方式は,高速伝送化に伴いDFT(Discrete Fourier Transform)の次数を高めることでPAPR(Peak-to-Average Power Ratio)が大きくなるという問題点がある.このため,LTE(Long Term Evolution)では,下りリンクではOFDM(Orthogonal Frequency Division Multiplexing),上りリンクではSC-FDMA(Single Carrier Frequency Division Multiple Access)方式が採用されている.マルチキャリヤ伝送方式にダイレクトコンバージョン受信機を採用する場合,広帯域化による受信機内部の自己混合によりDCオフセットが発生し,受信感度の劣化が大きな問題となる.本論文では,ダイレクトコンバージョン受信機におけるOFDM,SC-FDMA変調方式の受信信号におけるDCオフセットひずみの軽減方法を提案し,伝送特性を計算機シミュレーションにより評価した結果,従来の単純な平均振幅によるDC除去方式と比較してシンボル誤り率を改善できることを示す.

    CiNii

  • Improving Network Performance by Considering Count of Routes in Anycast Routing

    Martin Macuha, Takuro Sato

    WPMC 2009    2009年09月

  • Sampling Frequency O&#64256;set and Residual Carrier Frequency O&#64256;set Compensation method using Pilot symbol for OFDM Systems

    Hiroki Sugimoto, Takuro Sato, Hideyoshi Tominaga

    IEICE Journal   Vol.J92-B,No.9  2009年09月

  • An FEC Adaptive Multicast MAC Protocol for Providing Reliability in WLANs

    Anas Basalamah, Takuro Sato

    IEICE TRANSACTIONS ON COMMUNICATIONS   E92B ( 5 ) 1834 - 1840  2009年05月  [査読有り]

     概要を見る

    For wireless multicast applications like multimedia conferencing. voice over IP and video/audio streaming, a reliable transmission of packets within short delivery delay is needed. Moreover, reliability is crucial to the performance of error intolerant applications like file transfer. distributed computing, chat and whiteboard sharing. Forward Error Correction (FEC) is frequently used in wireless multicast, to enhance Packet Error Rate (PER) performance, but cannot assure full reliability unless coupled with Automatic Repeat Request forming what is knows as Hybrid-ARQ. While reliable FEC can be deployed at different levels of the protocol stack, it cannot be deployed on the MAC layer of the unreliable IEEE802.11 WLAN due to its inability to exchange ACKs with multiple recipients. In this paper. we propose a Multicast MAC protocol that enhances WLAN reliability by using Adaptive FEC and study it's performance through mathematical analysis and simulation. Our results show that our protocol can deliver high reliability and throughput performance.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • An FEC Adaptive Multicast MAC Protocol on Communications

    Anas Basalamah, Takuro Sato

    IEICE Transaction on Communication   Vol.E92-B  2009年05月

  • A Single Antenna Interference Cancellation Algorithm for OFDM systems

    Zhenyu Zhou, Takuro Sato

    IEEE 69th Vehicular Technology Conference (IEEE VTC2009)     1 - 5  2009年04月

    CiNii

  • Cognitive interference management in 3G femtocells

    Yang-Yang Li, Martin Macuha, Elvino S. Sousa, Takuro Sato, Masahiko Nanri

    IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC    2009年

     概要を見る

    We study a method of cognitive interference management in user-deployed 3G femtocell networks. Each femtocell cognitively recognizes an interference signature from the network environment and opportunistically allocates the proper channel patterns for interference minimization. Simulation results show great channel SINR improvement by implementing our opportunistic channel scheduler. The approach offers a novel view of autonomous spectrum management based on cognitive interference recognition and adaptive channel management. ©2009 IEEE.

    DOI

    Scopus

    67
    被引用数
    (Scopus)
  • Velocity adaptive vertical handoff on multi-frequency system

    Li Hua, Md. Humayun Kabir, Takuro Sato

    2009 IEEE 20TH INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS     773 - 777  2009年  [査読有り]

     概要を見る

    This paper describes the velocity adaptive vertical handoff algorithm on multi-frequency band wireless systems (V-MFVHO: Velocity adaptive Multi Frequency Vertical HandOff) in order to achieve the homogeneous handoff decision strategy. WiMAX Forum has published three licensed spectrum profiles: 2.3GHz, 2.5GHz and 3.5GHz. These frequency bands operated by WiMAX coexist on the same service area. In heterogeneous wireless networks, the problem is complicated since there are many differences cell coverage due to the frequency band, traffic conditions, data rate, and moving speed of MS (Mobile Station). This paper clarifies the design a scheme for selecting the candidate cells to satisfy the QoS requirements from each MS using the estimation of the location and the velocity of each MS by back-propagation neural network and the traffic and RSSI (Received Signal Strength Indicator) conditions of MS for each cell allocated for different frequency bands.

  • A Blind Single Antenna Interference Cancellation Algorithm for Asynchronous OFDM Communication Systems

    Zhenyu Zhou, Takuro Sato

    2009 IEEE 20TH INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS     1226 - 1230  2009年  [査読有り]

     概要を見る

    In orthogonal frequency division multiplexing (OFDM) based cellular systems, co-channel interference (CCI) from adjacent interfering base stations (BSs) operating and co-existing with the desired BS in the same frequency channel would greatly degrade the bit error rate (BER) performance of mobile receivers which are near to cell borders. CCI cancellation algorithms by using only one receiving antenna named single antenna interference cancellation (SAIC) have been under intense research. However, most of these algorithms require additional information from interfering signals. Furthermore, the orthogonality of a asynchronous interfering signal is destroyed and therefore, conventional SAIC algorithms cannot be applied. In this paper, we propose a blind SAIC algorithm named least mean square-blind joint maximum likelihood sequence estimation (LMS-BJMLSE) for asynchronous interference cancellation. The proposed LMS-BJMLSE algorithm is blind with respect to interfering signals and neither the training sequence (TS) nor pilot signal from interfering signals is needed. Its complexity is independent of channel length compared to the conventional time domain JMLSE algorithm. Simulation results show that the proposed LMS-BJMLSE algorithm could greatly improve the BER performance in both synchronous and asynchronous interference conditions.

  • Route-Count Based Anycast Routing in Wireless Ad hoc Networks

    Martin Macuha, Takuro Sato

    2009 IEEE 70TH VEHICULAR TECHNOLOGY CONFERENCE FALL, VOLS 1-4     263 - 267  2009年  [査読有り]

     概要を見る

    In anycast routing the packet is routed to anyone of the anycast group members. Anycast allows supporting many services and can significantly improve network performance of ad hoc networks. Unicast protocols have been extended to support anycast routing, however, these protocols consider solely the shortest path routing. The protocols based on a theory of potential fields have been proposed to improve packet delivery ratio in large mesh networks by routing to area with higher density of nodes instead of the shortest path routing. In this paper, we consider the density of nodes through count of routes. We propose simple anycast protocol which utilizes count of routes to the anycast group member as a routing metric and evaluate its performance.

  • Enhancement of beaconless location-based routing with signal strength assistance for Ad-hoc networks

    Guowei Chen, Kenichi Itoh, Takuro Sato

    IEICE TRANSACTIONS ON COMMUNICATIONS   E91B ( 7 ) 2265 - 2271  2008年07月  [査読有り]

     概要を見る

    Routing in Ad-hoc networks is unreliable due to the mobility of the nodes. Location-based routing protocols, unlike other protocols which rely on flooding, excel in network scalability. Furthermore, new location-based routing protocols, like, e.g. BLR [1], IGF [2], & CBF [3] have been proposed, with the feature of not requiring beacons in MAG layer, which improve more in terms of scalability. Such beaconless routing protocols can work efficiently in dense network areas. However, these protocols' algorithms have no ability to avoid from routing into sparse areas. In this article, historical signal strength has been added as a factor into the BLR algorithm, which avoids routing into sparse area, and consequently improves the global routing efficiency.

    DOI

    Scopus

    5
    被引用数
    (Scopus)
  • Verification of Adaptive switching DC offset cancellation schemes on direct conversion receiver

    Kazuhio Tamesue, Masahiro Moriya, Takuro Sato

    IEICE journal paper B   Vol.J91-B No.4  2008年04月

  • An Energy Estimation Model for Mobile Sensor Networks

    Muhammad Tariq, Martin Macuha, Yong-Jin Park, Takuro Sato

    2010 FOURTH INTERNATIONAL CONFERENCE ON SENSOR TECHNOLOGIES AND APPLICATIONS (SENSORCOMM)     507 - 512  2008年

     概要を見る

    Mobile sensor networks have received significant attention recently. Mobile sensors are deployed to achieve network load balancing, prolonging network lifetime, and improving network coverage, by monitoring critical areas where manual sensor deployment cannot be performed. To achieve these goals, energy estimation is one of the main constraints and concerns to consider, while deploying mobile sensors in a sensor field. Most of the energy models designed for sensor networks assumed static sensors. In this paper, we propose a comprehensive energy model to estimate the overall energy consumption through power dissipation, for both static and mobile sensors in the potential sensor fields. We calculate the total remaining lifetime of mobile sensor networks from the total power dissipation. By predicting the remaining lifetime of any network in different network scenarios at a given instance of time, an optimum network strategy can be designed for a given application.

    DOI

    Scopus

    7
    被引用数
    (Scopus)
  • Adaptive FEC reliable multicast MAC protocol for WLANs

    Anas Basalamah, Takuro Sato

    2007 IEEE 66TH VEHICULAR TECHNOLOGY CONFERENCE, VOLS 1-5     244 - 248  2007年  [査読有り]

     概要を見る

    For end-to-end wireless multicast applications like multimedia conferencing, voice over IP and video/audio streaming applications which require reliable transmission of frames within short delivery delay, adding MAC layer H-ARQ (Hybrid Automatic Repeat Request) can enhance reliability and delivery delay. However, IEEE802.11 does not support reliable multicast due to its inability to exchange ACKs with multiple recipients. In this paper, we propose a protocol that enhances WLAN reliability performances by using Adaptive FEC (Forward Error Correction) while maintaining an optimal throughput performance.

  • A rate adaptive multicast protocol for providing MAC layer reliability in WLANs

    Anas Basalamah, Hiroki Sugimoto, Takuro Sato

    IEICE TRANSACTIONS ON COMMUNICATIONS   E89B ( 10 ) 2733 - 2740  2006年10月  [査読有り]

     概要を見る

    IEEE802.11b standard provides 1, 2, 5.5, 11 Mbps data rates. These data rates can be made possible by using different modulation techniques: DBPSK, DQPSK, CCK5.5 and CCK11 respectively. Rate adaptation is the process of dynamically selecting a proper modulation scheme depending on channel conditions in order to improve total throughput. Current rate adaptation protocols deal with unicast links rather than multicast. Measuring the received Signal Strength (RSS) of a feedback message (CTS, ACK) to estimate the receiver's link condition, can be one way to do this. A receiver may send its channel condition information to the sender allowing it to adapt its data rate for the following transmission. IEEE802.11 standard however, does not provide feedback messages for MAC layer recovery on multicast frames. This is due to collisions occurring if multicast group members simultaneously initiate a feedback message. Therefore, in order to link adapt multicast, a reliable multicast MAC protocol has to be introduced. In this paper, we propose a Rate Adaptive Multicast (RAM) protocol which provides reliability to WLANS and enhances its throughput by using Rate Adaptation. Further, we evaluate our protocol by throughput analysis and computer simulation. Simulation results suggest that our protocol performs better than related/existing protocols in both throughput as well as reliability.

    DOI

    Scopus

    13
    被引用数
    (Scopus)
  • Rate Adaptive Reliable Multicast MAC Protocol for WLANs

    Anas Basalamah, Hiroki Sugimoto, Takuro Sato

    2006 IEEE 63RD VEHICULAR TECHNOLOGY CONFERENCE, VOLS 1-6     1216 - 1220  2006年  [査読有り]

     概要を見る

    IEEE802.11b standard provides 1, 2, 5.5, 11 Mbps data rates. These data rates can be made possible by using different modulation techniques: DBPSK, DQPSK, CCK5.5 and CCK11 respectively. Rate adaptation is the process of dynamically selecting a proper modulation scheme depending on channel conditions in order to improve total throughput. Current rate adaptation protocols deal with unicast links rather than multicast. Channel conditions can be estimated by measuring the Received Signal Strength (RSS) of a feedback message (CTS, ACK). However, IEEE802.11 standard does not provide feedback messages for MAC layer recovery on multicast frames. This is due to collisions which may occur to simultaneous feedback messages from multicast group members. Therefore, in order to rate adapt multicast, a reliable multicast MAC protocol has to be introduced. In this paper, we propose a protocol which provides multicast reliability to WLANs and enhances its throughput by using rate adaptation. Further, we evaluate our protocol by throughput analysis and computer simulation. Simulation results suggest that our protocol performs better than a related/existing protocol in both throughput as well as reliability performances.

  • フル光接続光無線システムの研究開発(1)—ファイバ直接受光型光無線装置の開発及び評価の一検討—

    大前和憲, カムギシャ カザウラ, 松本充司, 佐藤拓朗, 羽鳥光俊, 鮫島彰孝, 鈴木敏司, 高橋浩一, 松本秀樹, 若森和彦, 度情報通信推進協議会, 淺谷耕一

    電子情報通信学会全国大会   B-5-167  2005年03月

  • ダイレクトコンバージョンにおけるDCオフセット電圧の抑圧に関する検討

    爲末和彦, 森屋正弘, 松本圭介, パナソニックモバイルコミュニケーションズ, 中村 文(パナソニックモバイル仙台研究, 佐藤拓朗

    電子情報通信学会全国大会   B-5-127   576 - 576  2005年03月

    CiNii

  • Buffering Stream UDP Packets control in FMIPv6 handoff

    BASALAMAH Anas(Waseda Uni, Kenich ITO(KSC, Hiroki SUGIMOTO(Niigata, Institute of Technology, Takuro SATO(Waseda U

    電子情報通信学会全国大会   B-6-23  2005年03月

  • Inner-chip-interference cancellation using Rake receiver with Wiener filter

    TT Tsai, S Watanabe, YL Huang, T Sato

    IEICE TRANSACTIONS ON COMMUNICATIONS   E87B ( 11 ) 3295 - 3302  2004年11月  [査読有り]

     概要を見る

    In this paper, a sub-optimal Rake receiver combined with a Wiener Filter is investigated for use in an indoor environment. InnerChip-interference is dominant when the application is indoors, so the innerchip-interference rejection function becomes critical for the receiver. Pilot symbols in each slot are used for channel estimation and weight calculation of Rake combining through Wiener Filter. Compared to conventional combining which uses maximum ratio combining, Wiener combining using IRC (Interference rejection combining) achieves better ICI (Inner-chipInterference) rejection. This paper clarified that the sub optimal Rake receiver using Wiener Filter is 4 dB better than the conventional Rake receiver under the indoor application.

  • Study of orthogonal SSB modulation method

    GI Ohta, M Uesugi, T Sato, H Tominaga

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E87A ( 10 ) 2676 - 2683  2004年10月  [査読有り]

     概要を見る

    This paper proposes a new SSB-QPSK modulation/demodulation method. The present method multiplexes the USB (Upper Side Band) and LSB (Lower Side Band) of a QPSK-modulated SSB (Single Side Band) on the same SSB complex frequency band. The present method thus achieves 2 bit/s/Hz. This method is an orthogonal SSB-QPSK method, because the multiplex signals are orthogonal to each other. The demodulator consists of two SSB demodulators. A simulation result in AWGN conditions, shows that the proposed method has better BER (Bit Error Rate) performance than 16 QAM. The degradation of BER in comparison with QPSK is less than 0.2 dB on Eb/No (bit-energy-to-noise-power ratio). In a fading/Doppler environment, the BER performance of the orthogonal SSB-QPSK is the same as that of QPSK.

  • SSB化QPSK変調方式の一検討(その2)

    太田現一郎, 上杉充, 佐藤拓朗, 富永英義

    電子情報通信学会全国大会   A-5-22  2004年03月

  • A consideration on a modem for high efficiency of frequency use

    Gen-ichiro Ohta, Mituru Uesugi, Takuro Sato, Hideyoshi Tominaga

    Wireless Personal Multimedia Communications   Vol.3   470 - 473  2004年

  • Improved CMOS microwave linearity based on the modified large-signal

    Hong-Hsin Lai, Chao-Chih Hsiao, Chin-Wei Kuo, Yi-Jen Chan, Takuro Sato

    IEIEC、Transactions   Vol.E87  2003年11月

  • A consideration on digital modulation on SSB for high spectral efficiency

    Gen-ichiro Ohta, Mituru Uesugi, Takuro Sato, Hideyoshi Tominaga

    IEEE/IEICE APSITT2003 conference     397 - 402  2003年11月

    CiNii

  • System evaluation of a chip interference cancellation rake receiver with

    Chih Hao Wu, Tsung-tingTsai Yung Liang Huang, Takuro Sato

    Wireless Personal Multimedia Communications   Vol.3   342 - 345  2003年10月

  • Experimental results of radio propagation characteristics at 2.45 GHz and 5Ghz

    Hong hsin Lai, Hiroki-Sugimoto, Souich Watanabe, Takuro Sato

    Wireless Personal Multimedia Communications   vol.1   162 - 165  2003年10月

  • SSB化QPSK変調方式の実証化検証

    太田現一郎, 上杉充, 佐藤拓朗, 富永英義

    電子情報通信学会ソサイアティ大会   B-5-129  2003年09月

  • SSB化QPSK変調方式の一検討

    太田現一郎, 上杉充, 佐藤拓朗, 富永英義

    電子情報通信学会ソサイアティ大会   B-5-206  2003年09月

  • Turbo 符号を用いたOFDM無線LANの検討と評価

    鈴木祐介, 渡辺壮一, 佐藤拓朗

    電子情報通信学会全国大会    2003年07月

  • Performance of handoff algorithm based on distance and RSSI measurements

    KI Itoh, S Watanabe, JS Shih, T Sato

    IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY   51 ( 6 ) 1460 - 1468  2002年11月  [査読有り]

     概要を見る

    The performance of a proposed handoff algorithm based on both the distance of a mobile station to neighboring base stations and the relative signal strength measurements is evaluated. The algorithm performs handoff when the measured distance from the serving base station exceeds that from the candidate base station by a given threshold and if the measured signal strength of the adjacent base station exceeds that of the serving base station by a given hysteresis level. The average handoff delay and average number of handoffs are used as criteria for performance. Numerical results are presented to demonstrate the feasibility of the distance-based handoff algorithm, including results for an additional criterion based on relative signal strength. The proposed algorithm is compared with an algorithm based on absolute and relative signal strength measurements and with a solely distance-based algorithm. It is found that the proposed handoff algorithm performs well in a log-normal fading environment when the distance estimate error is modeled by wide-sense stationary additive white Gaussian noise.

    DOI

    Scopus

    93
    被引用数
    (Scopus)
  • Performance analysis of distance-assisted handoff algorithm in multi-cellular systems

    JS Shih, KI Itoh, S Watanabe, T Sato

    IEICE TRANSACTIONS ON COMMUNICATIONS   E85B ( 9 ) 1676 - 1684  2002年09月  [査読有り]

     概要を見る

    This paper assesses the performance of the handoff algorithm based on distance and RSSI measurements in a multi-cellular environment by computer simulation. The algorithm performs a handoff if handoff initiation conditions, handoff possible conditions, and handoff selective conditions are met. The performance criteria are based on the average number of handoffs, the crossover points and the average number of outages. Numerical results are presented to demonstrate the feasibility of the algorithm. The performance of the distance-assisted handoff algorithm is compared with that of a conventional algorithm that utilizes signal strength alone. Overall, the distance-assisted algorithm exhibits higher performance in average number of handoffs and the crossover points, yet exhibits a higher number of outages on average than the conventional algorithm.

  • Higher data rate wireless LAN system based on OFDM

    H Sugimoto, D Sasagawa, Y Suzuki, S Watanabe, T Sato

    5TH INTERNATIONAL SYMPOSIUM ON WIRELESS PERSONAL MULTIMEDIA COMMUNICATIONS, VOLS 1-3, PROCEEDINGS     734 - 737  2002年  [査読有り]

     概要を見る

    In this paper, the performance of a higher data rater OFDM system based on IEEE802.11a is described. The performance of the OFDM system which is applied 256QAM and 1024QAM to obtain higher data rate than 64QAM, are evaluated in A WGN and multi path fading environment. Also the system with ADC performance and required SNR are given. This shows 1024QAM OFDM system has capability of an candidate of the higher data rate wireless LAN system, target to 100Mbps.

  • Down-link rake receiver for WCDMA with Wiener filter

    TT Tsai, W Soichi, YL Huang, T Sato

    5TH INTERNATIONAL SYMPOSIUM ON WIRELESS PERSONAL MULTIMEDIA COMMUNICATIONS, VOLS 1-3, PROCEEDINGS     377 - 381  2002年  [査読有り]

     概要を見る

    In this paper,a simplified and sub-optimal wideband CDM4 downlink rake receiver with Wiener combining is investigated. Pilot symbols in each of slots will be used for channel delay estimation and weight calculation. Compared to conventional combining which uses MRC(maximum ratio combining), Wiener combining which uses IRC (Interference rejection combining) can get better MAI (Multiple Access Interference) rejection. For AWGN channel and Clarke's Rayleigh Fading channel with four performance of the independent paths, We simulate the BER per rake receiver with Wiener filter. From the simulation result, although we get about 1.5dB performance degraded in AWGN and 6 to 7 dB degraded in Rayleigh Fading channel as compared to the ideal performance, its simplified algorithm can be an advantage of implementation.

  • Analysis and simulation results of multihop handoff scheme in an ad hoc wireless network

    F Urasawa, KI Itoh, L En-Shang, T Sato

    5TH INTERNATIONAL SYMPOSIUM ON WIRELESS PERSONAL MULTIMEDIA COMMUNICATIONS, VOLS 1-3, PROCEEDINGS     1366 - 1369  2002年  [査読有り]

     概要を見る

    We analyzed the handoff performance of a multihop-based wireless LAN that uses Access Points (APs) for communication. When a mobile terminal isn't able to communicate with any APs, it uses other mobile terminals as Terminal Repeaters (TRs). The handoff criteria are based on absolute and relative signal strengths. The performance criteria are the average number of handoffis and the average handoff delay. We investigated the relation between the handoff criteria and the performance criteria when both the mobile terminal and the terminal repeaters are moving. Numerical results are presented to show that the average handoff delay decreases but the average number of handoffis increases as the TRs' moving speed is increased.

  • Performance Analysis of Handover Algorithm using Both Distance and RSSI Measurements

    伊藤建一, 渡辺壮一, 佐藤拓朗

    The Third International Symposium on Wireless Personal Multimedia Communications     773 - 778  2001年10月

  • Performance Analysis of Distance-Assisted Handoff Algorithm in Multi-Cellular Systems

    施鑑修, 伊藤建一, 渡辺壮一, 佐藤拓朗

    Wireless Personal Multimedia Communication     335 - 340  2001年09月

    CiNii

  • 双曲線による電波源位置特定方式と特性解析

    渡辺壮一, 伊藤建一, 佐藤拓朗, 星子芳三郎

    電子情報通信学会論文誌B   Vol.J84-B ( No.6 ) 1033 - 1042  2001年06月

     概要を見る

    任意の電波を発射する電波源の位置を双曲線法を用いて推定する.双曲線法における位置測定精度は各センサ間の距離差検出精度に依存する.距離差は電波の伝搬遅延時間差に光速を乗じることにより得られるため, 高精度な時間差検出が必須である.本論文では, 従来時間軸上で直接行っていたセンサ局間の伝搬遅延時間差検出を周波数軸上で行った.周波数上に展開した各周波数成分の位相を検出し, 位相差を各成分の受信電力に応じて合成した後に時間差に換算することにより, 高精度な時間差推定が可能となる.シミュレーションの結果, マルチパスフェージング伝搬環境, 未知局信号のベースバンド帯域幅±3kHz, S/N10dBにおいて, 80〜260mの位置測定精度が得られることを明らかにした.

    CiNii

  • OFDM伝送技術の現状と将来

    佐藤拓朗, 渡辺壮一, 施鑑修

    シミュレーション学会小特集     12 - 15  2001年03月

  • Burst synchronization scheme for millimeter band OFDM

    S Watanabe, K Itoh, F Urasawa, T Sato

    IEEE 54TH VEHICULAR TECHNOLOGY CONFERENCE, VTC FALL 2001, VOLS 1-4, PROCEEDINGS     1706 - 1710  2001年  [査読有り]

     概要を見る

    Burst synchronization scheme for millimeter band OFDM uplink system is proposed. For the estimation of subscribers access and its frequency offset and time offset, OFDM-CDMA pilot signal is adopted. The accuracy and probability of error estimation are investigated by the theoretical analysis and simulations. This paper clarified that the proposed synchronization scheme has the capacity of four users simultaneous access with 10% of error estimation probability, when 64 of the number of subchannels are used for spreading each subscribers pilot signal.

  • Bit Error Rate Evaluation of OFDM-CDMA Wireless Mobile Communication System under Multi-Path Fading Channel

    渡辺壮一, 佐藤拓朗, 阿部武雄

    The Third International Symposium on Wireless Personal Multimedia Communications     44 - 47  2000年11月

  • Mobile station location in CDMA cellular networks

    伊藤建一, 渡辺壮一, 佐藤拓朗

    The 7th international workshop on Mobile Multimedia Communications     1 - 6  2000年10月

  • Two dimensional equalization scheme of orthogonal coding multi-carrier CDMA under frequency selective fading

    佐藤拓朗, 渡辺壮一, 阿部武雄

    NOLTA’99     887 - 890  1999年11月

  • 周波数有効利用技術におけるグラフネットワーク理論の適用

    佐藤拓朗, 田村博, 阿部武雄

    電子情報通信学会特別小特集情報通信の将来の基礎に向けて     922 - 926  1999年09月

  • Adaptive Forward Subchannel Control Scheme of OFDM Mobile Communication System

    真壁, 渡辺壮一, 佐藤拓朗, 阿部武雄

    IEEE VTC'99-Fall     2438 - 2441  1999年09月

  • Forward subchannel control scheme for TDD multi-carrier mobile communication system

    S Watanabe, T Sato, T Abe

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E82A ( 7 ) 1172 - 1178  1999年07月  [査読有り]

     概要を見る

    This paper describes a forward subchannel control of multi-carrier scheme intended to compensate for phase/amplitude distortions under frequency selective fading. The forward subchannel control scheme is used for a Time Division Duplex (TDD) multi-carrier system on up-link. The forward subchannel control scheme provides forward subchannel control of phase/amplitude variation and subchannel assignment control. These controls are applied before transmission of an up-link signal. The forward control parameters are estimated by a preamble down-link signal. Simulation results clarify that the BER performance with the forward subchannel control scheme shows a superiority of more than one order at the condition of 22 dB of E-b/N-o and 400 Hz of fading frequency.

  • Equalization technique of inner chip distortion multi-carrier CDMA scheme

    S Watanabe, T Sato, T Abe

    1999 IEEE 49TH VEHICULAR TECHNOLOGY CONFERENCE, VOLS 1-3     2418 - 2421  1999年  [査読有り]

     概要を見る

    This papa describes an equalization scheme of an inner chip distortion which is awed by multi-path fading on a multi-carrier CDMA system. The proposed equalization scheme uses Auto-regressive Process model (AR) and prediction parameters of AR are obtained by Recursive Last Square algorithm (RLS). Simulation results of the multi-carrier CDMA system using the inner chip equalizer clarified that BER is 1.1x10(-2) at 20 dB of Eb/NO under the condition of two multi-path fading environments of which delay time is 2 mu sec and 100 Hz Of fading frequency. In the evaluation of system parameters of the multi-carrier CDMA, number of subchannels are 16, data rate is 32 kbps and spreading ratio is 16.

  • Bit Error Rate evaluation of the multi-carrier CDMA modulation under frequency selective fading

    S Watanabe, T Sato, T Abe

    GLOBECOM'99: SEAMLESS INTERCONNECTION FOR UNIVERSAL SERVICES, VOL 1-5     681 - 685  1999年  [査読有り]

     概要を見る

    This paper describes the Bit Error Rate (B.E.R) performance of the mult-carrier CDMA modulation under the frequency selective fading. The multi-carrier CDMA signal is obtained by spreading the multicarrier signal using the peculiar PN (Pseudo Random) code. The received multi-carrier CDMA signal is correlated and demodulated by the rake receiver. The output signal of the rake receiver is converted to subchannel signals through the discrete fourier transform (dft) and the received data is detected through S/P (Serial Parallel converter). This paper clarifies that BER performance of the multi-carrier CDMA becomes 10(-3) under the condition of two multipath condition and 100 Hz of the fading frequency.

  • Two dimensional equalization scheme of orthogonal coding multi-carrier CDMA

    S Watanabe, T Sato, M Sengoku, T Abe

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E81A ( 6 ) 1079 - 1088  1998年06月  [査読有り]

     概要を見る

    This paper describes two dimensional (2D) equalization scheme of orthogonal coding multi-carrier CDMA for reverse link of mobile communication systems. The purpose of the 2D equalization is the reduction of Multiple Access Interference (MAI) which is caused by the random access and the different propagation path from each mobile station. The orthogonal coding multi-carrier CDMA multiplexes all mobile stations' data by Code Division Multiplexing (CDM). The 2D coding scheme spreads a preamble signal at time (in subchannel signals) and frequency (between subchannel signals) domains. The 2D decoding scheme estimates transmission delay time and instantaneous fading frequency from preamble signal for individual mobile stations and compensate the received data using these estimation values to reduce MAI.

  • Two dimensional equalization scheme of orthogonal coding multi-carrier CDMA under frequency selective fading environment

    T Sato, S Watanabe, T Abe

    ICUPC &apos;98 - IEEE 1998 INTERNATIONAL CONFERENCE ON UNIVERSAL PERSONAL COMMUNICATIONS, VOLS 1 AND 2   1-2   1215 - 1219  1998年  [査読有り]

  • Bit error rate evaluation of delay time control scheme for reverse channel on orthogonal coding multi-carrier CDMA

    S Watanabe, T Sato, M Sengoku, T Abe

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E80A ( 7 ) 1226 - 1232  1997年07月  [査読有り]

     概要を見る

    This paper describes a delay control scheme for synchronous detection of an orthogonal coding multi-carrier CDMA (Code Division Multiple Access) system. The delay control scheme estimates transmission timing of data from each mobile station. At a base station. delay time is obtained by detecting phase shift value of the preamble signal from each mobile station. The estimated transmission timing information is sent from base station to each mobile station and the mobile station then adjusts its transmission timing. Simulation results clarified that Bit Error Rate (BER) is 2.5 x 10(-3) at 19 dB of E-b/N-0 under conditions of 29.4 msec initial delay time, 32 kbit/sec data rate, 16 subchannels and 100 Hz of fading frequency.

  • Wideband CDMA personal communications system featuring ISDN compatibility

    R Fisher, H Suyderhoud, T Kato, A Fukasawa, T Sato

    1997 IEEE 47TH VEHICULAR TECHNOLOGY CONFERENCE PROCEEDINGS, VOLS 1-3     1777 - 1781  1997年  [査読有り]

     概要を見る

    T1P1 J-STD-015 (TIA IS-665) is a 1.9 GHz wideband CDMA personal communications system which was standardized in the U.S.A. during 1995. At present, the W-CDMA maximum data rate is specified at 64 kbps which allows G4 facsimile transmission. W-CDMA is a candidate for wireless local loop (WLL) applications. The WLL requires ISDN compatibility at the air interface. This paper describes an improvement to the W-CDMA data transmission system which provides full 2B+D ISDN (Integrated Services Digital Network) capability.

  • Equalization scheme of orthogonal coding multi-carrier CDMA scheme under multi-path fading environment

    T Sato, S Watanabe, T Abe

    1997 IEEE 47TH VEHICULAR TECHNOLOGY CONFERENCE PROCEEDINGS, VOLS 1-3     1887 - 1891  1997年  [査読有り]

     概要を見る

    This paper clarifies an estimation method of a carrier offset frequency of an orthogonal coding multi-carrier CDMA system under a multi-path fading. This paper analyzes an inter channel interference and an inner channel interference which are caused by the multicarrier offset frequency. An estimation method of the carrier offset frequency adopts a prediction method. Prediction coefficients are obtained by Burg algorithm of a Maximum entropy method. As a result of a simulation, it shows that Bit Error Rate (BER) is 3.5x10(-2) at 15 dB of E-6/N-0 for 32 kbit/sec of data rate and 16 subchannels of the orthogonal coding multi-carrier CDMA under a multi-path fading environment.

  • Wideband CDMA system

    深沢敦司, 佐藤拓朗, 川辺 学, 滝沢由美, 加藤俊雄

    IEEE ISSTA     450 - 455  1996年09月

  • Synchronization Analysis of Orthogonal coding multi-carrier CDMA under multi-path fading

    佐藤拓朗, 渡辺壮一, 阿部武雄

    ITC-CSCC'96   1   46 - 49  1996年07月

    CiNii

  • Modulation and Demodulation Characteristics of Orthogonal Coding Multi-carrier CDMA Scheme

    佐藤拓朗, 渡辺壮一, 阿部武雄

    MDMC'96     740 - 744  1996年07月

    CiNii

  • Group 3 Error-Free Facsimile Terminal for Analog Cellular Networks

    Manabu Kawabe, Toshio Kato, Takuro Sato, Masaharu Bessho, Atsushi Fukasawa

    IEEE Transactions on Vehicular Technology   45 ( 1 ) 64 - 73  1996年

     概要を見る

    Group 3 error-free facsimile terminal for use in an analog cellular network has been developed. This facsimile terminal is provided with the International Telecommunication Union (ITU-T, formerly CCITT) T.30 recommendation protocol and an adaptive error control scheme (AECS) for Group 3 communication and error-free communication. The AECS monitors the channel conditions and selects the optimum error correction code. ITU-T V.27ter is used as the modulation method and the transmission rate is 4800 bps. This system is compatible with the modified Huffman (MH), modified READ (MR), and modified modified READ (MMR) image data compression codes. The average communication time of this facsimile terminal is 40 s per page under moving condition through the analog cellular network. © 1996 IEEE.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Wideband CDMA system for personal communications services

    RE Fisher, A Fukasawa, T Sato, Y Takizawa, T Kato, M Kawabe

    1996 IEEE 46TH VEHICULAR TECHNOLOGY CONFERENCE, PROCEEDINGS, VOLS 1-3     1652 - 1655  1996年  [査読有り]

  • Sequential Interference Cancellation System applying to wideband CDMA systems

    T Sato, K Manabu, A Kawahashi, T Kato, A Fukasawa

    1996 IEEE 46TH VEHICULAR TECHNOLOGY CONFERENCE, PROCEEDINGS, VOLS 1-3     1366 - 1370  1996年  [査読有り]

  • Wideband CDMA system for personal communications services

    深沢敦司, 佐藤拓朗, 川辺 学, 滝沢由美, 加藤俊雄

    IEEE ICNNSP     337 - 340  1995年12月

  • Interference cancellation system based on DS-CDMA scheme

    佐藤拓朗, 川辺 学, 川橋明世志, 加藤俊雄, 深沢敦司

    IEEE ICNNSP     341 - 344  1995年12月

  • Wideband CDMA system for personal communication

    深沢敦司, 佐藤拓朗, 加藤俊雄

    4th IEEE ICUPC'95     833 - 837  1995年11月

  • Data transmission architecture of wideband CDMA system

    加藤俊雄, 佐藤拓朗, 深沢敦司

    4th IEEE ICUPC'95     743 - 747  1995年11月

  • Configuration and its performance of an interference cancellation system using pilot signal for radio channel estimation

    深沢敦司, 佐藤拓朗, 川辺 学, 佐藤慎一, 杉本大樹

    IEICE Trans. B-Ⅱ,Vol.J77-B-Ⅱ   77 ( 11 ) 628 - 640  1994年12月

    CiNii

  • EVALUATION OF INNERCELL AND INTERCELL INTERFERENCE ON CDMA SYSTEM

    M KAWABE, T SATO, T KATO, A FUKASAWA

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E77A ( 6 ) 993 - 999  1994年06月  [査読有り]

     概要を見る

    In implementing the future Personal Communication Services (PCS), providing a system allowing simultaneous access by many subscribers is of utmost importance. The study of CDMA, as a candidate for the radio access method is being promoted for this purpose. Increasing the CDMA system capacity is determined by; the selection of a spread code having an excellent correlation characteristic [1]; the interference cancellation method [2], [3], and; the method for controlling the power accordance with the near-far problems [4]. In this paper we considered the cellular system, and have analyzed the correlation characteristic by using the PN or Walsh code as the innercell spreading code and the PN or Gold code as the intercell spreading code. We have also analyzed the system capacity in terms of the correlation characteristics for different combinations of these spreading codes. It has been clarified as a result that 40 subscriber channels can be accommodated per cell by using the Walsh code and PN code as the innercell and intercell codes for the forward link (the Base Station (BS) to the Personal Station (PS)) and the PN code as both the innercell and intercell codes for the reverse link (the PS to the BS).

  • パイロット信号を用いた伝搬路推定に基づく干渉キャンセラの構成とその特性

    深沢敦司, 佐藤拓朗, 川辺 学, 佐藤慎一, 杉本大樹

    電子情報通信学会論文誌 B-Ⅱ,Vol.J77-B-Ⅱ、No.11     628 - 640  1993年11月

  • advanced CDMA scheme for personal communication services

    深沢敦司, 佐藤拓朗, 徳田清仁, 川辺 学

    JTC-CSCC'93     252 - 255  1993年07月

    CiNii

  • Evaluation of inner cell and inter cell interference on CDMA system

    川辺 学, 佐藤拓朗, 加藤俊雄, 川橋明世志

    JTC-CSCC'93     256 - 261  1993年07月

  • Neural network configuration for multiple sound source location and its performance

    佐藤慎一, 佐藤拓朗, 深沢敦司

    IEICE Trans.Fundamental,Vol.E76-A,No.5   76   754 - 760  1993年03月

    CiNii

  • Throughput Analysis Method for Hybrid ARQ Schemes Over Burst Error Channels

    Takuro Sato, Manabu Kawabe, Toshio Kato, Atsushi Fukasawa

    IEEE Transactions on Vehicular Technology   42 ( 1 ) 110 - 118  1993年

     概要を見る

    We presented a definition of a burst error channel using a Markov model in a previous paper [1]. This paper described a throughput analysis method of a hybrid automatic repeat request (ARQ) under the burst error channel using the three-state Markov model. The hybrid ARQ was studied for the random and burst error correction codes as the forward error correction (FEC) code, and multiframe rejection (MREJ) as the ARQ. The throughput efficiency was obtained with both an infinite buffer memory and a finite buffer memory. The applicable range of the burst error channel has been clarified for the hybrid ARQ using random and burst error correction codes. © 1993 IEEE

    DOI

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    23
    被引用数
    (Scopus)
  • FREQUENCY-SELECTIVE FADING MODEL ON NEAR-FAR PROBLEM IN M-ARY CDMA COMMUNICATION

    K TOKUDA, Y SHIRAKI, S SHIMIZU, T SATO

    1993 43RD IEEE VEHICULAR TECHNOLOGY CONFERENCE     460 - 463  1993年  [査読有り]

  • ADVANCED CDMA SCHEME BASED ON INTERFERENCE CANCELLATION

    M KAWABE, T KATO, A KAWAHASHI, T SATO, A FUKASAWA

    1993 43RD IEEE VEHICULAR TECHNOLOGY CONFERENCE     448 - 451  1993年  [査読有り]

  • TECHNICAL ISSUES OF MOBILE COMMUNICATION-SYSTEMS FOR PERSONAL COMMUNICATIONS SERVICES

    T SATO, T SUZUKI, K HORIGUCHI, A FUKASAWA

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E75A ( 12 ) 1625 - 1633  1992年12月  [査読有り]

     概要を見る

    This paper describes a perspective on Personal Communications Services (PCS) and technological trends. It takes into consideration rules pertaining to the use of PCS for mobile radio communication and countermeasures to cope with the huge increase in PCS subscribers. In this paper, PCS network structures, inter-regional roaming, microcell structure, radio access and channel access methods are also covered as PCS technologies. Furthermore, trends in domestic and international standards are also described. Although these technologies present many difficulties, we believe that they will be overcome and PCS services will be introduced in the near future.

  • PROTOCOL CONFIGURATION AND VERIFICATION OF AN ADAPTIVE ERROR CONTROL SCHEME OVER ANALOG CELLULAR NETWORKS

    T SATO, M KAWABE, T KATO, A FUKASAWA

    IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY   41 ( 1 ) 69 - 76  1992年02月  [査読有り]

     概要を見る

    A high-speed and error-free voiceband data communication method using a hybrid automatic repeat request (ARQ) protocol over an analog cellular system is described. The present method adopts an adaptive error control scheme (AECS). This error control scheme automatically selects the optimal error correction code according to circuit bit error rate (BER), so as to match it to the frequently changing mobile radio propagation paths (MRPP) conditions. This method adopts multiframe rejection (MREJ) as a retransmission scheme for a high throughput efficiency on the burst error circuit. Actual field evaluation was made by mounting this protocol on a CCITT V.22bis modem with a data transmission speed of 2400 b/s and a modulation method using 16 carrier states over the Advanced Mobile Phone Service (AMPS) in Atlanta, GA, verifying that data communication can be achieved with an average throughput efficiency of 70% over a radio channel having a BER up to 10(-2).

  • ERROR-FREE GROUP-3 FACSIMILE TERMINAL FOR CELLULAR MOBILE TELEPHONE CIRCUIT

    M KAWABE, T YOSHIDA, T SATO, H ETOH, M BESSHO

    VEHICULAR TECHNOLOGY SOCIETY 42ND VTS CONFERENCE - FRONTIERS OF TECHNOLOGY : FROM PIONEERS TO THE 21ST CENTURY, VOLS 1 AND 2     89 - 92  1992年  [査読有り]

  • EVALUATION RESULTS FOR GROUP-3 FACSIMILE TRANSMISSION OVER THE DIGITAL CELLULAR-SYSTEM USING THE TRANSPARENT MODE

    T SATO, M KAWABE, T KATO, A FUKASAWA

    IEICE TRANSACTIONS ON COMMUNICATIONS ELECTRONICS INFORMATION AND SYSTEMS   74 ( 10 ) 2990 - 3000  1991年10月  [査読有り]

     概要を見る

    This paper describes the evaluation results for Group 3 (G3) facsimile transmission in the transparent mode over the digital cellular system. Effectiveness of a convolutional code is clarified for encoding the G3 facsimile data from analysis of error correction capability for the transparent mode. The 1/2 convolutional code is used as the error correction code in the digital cellular circuit, and a simulation experiment is conducted at the data transmission speed of 4,800 bit/sec in a G3 facsimile. It has been clarified that the transparent transmission system is applicable up to a fading frequency of 80 Hz, a received power of -100 dBm and a handoff occupancy frequency of 4 times per minute on asumption of handoff occurrence probability in a Poisson distribution. This scheme presents the high reliable G3 facsimile transmission which does not depend on delay time of the digital cellular system.

  • Group3 facsimile communication scheme in transparent mode on digital cellular network

    佐藤拓朗, 川辺 学, 加藤俊雄, 深沢敦司

    IEEE ISCAS、Vol.2 of 5     958 - 961  1991年06月

  • SIMULATION OF BURST ERROR MODELS AND AN ADAPTIVE ERROR CONTROL SCHEME FOR HIGH-SPEED DATA-TRANSMISSION OVER ANALOG CELLULAR-SYSTEMS

    T SATO, K TOKUDA, M KAWABE, T KATO

    IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY   40 ( 2 ) 443 - 452  1991年05月  [査読有り]

     概要を見る

    To realize high speed data communication in a cellular system, the characteristics of mobile radio propagation paths (MRPP), and a robust error control scheme for poor circuit quality must be studied. This paper discusses the following: 1) MRPP are analyzed by computer simulation, and an analysis method is described that used a Markov model for burst errors generated by the simulation. 2) By simulating the locus of moving vehicles, the relationship between the carrier-to-noise ratio (CNR), the fading frequency of a moving vehicle and the three-states Markov model is shown. 3) An adaptive error control scheme (AECS) is constituted as an effective high speed data communication scheme in an analog cellular system. The effectiveness of the AECS is analyzed by simulating its application rate, using the three-states Markov model. 4) An in a subcarrier transmission system with a 4800 b/s data transmission rate, using the three-states Markov model. 4) An assessment using actual field data in the U.S. and the U.K. is also performed, and the analysis method is verified and the characteristics of the AECS are evaluated using the data.

  • STUDY ON FACSIMILE TRANSMISSION THROUGH DIGITAL CELLULAR-SYSTEM

    T SATO, M KAWABE, T KATO, A FUKASAWA

    41ST IEEE VEHICULAR TECHNOLOGY CONFERENCE     138 - 143  1991年  [査読有り]

  • Group3 facsimile transmission scheme over cellular systems

    佐藤拓朗, 川辺 学, 加藤俊雄, 深沢敦司

    JTC-CSCC'90、J41     140 - 144  1990年12月

  • 適応符号化による誤り制御データ通信方式の構成と適用効果

    佐藤拓朗, 川辺 学, 加藤俊雄, 深沢敦司

    電子情報通信学会論文誌B−Ⅰ,J72−B−I No.5   72 ( 5 ) 438 - 445  1989年05月

    CiNii

  • Data transmission protocol in integrated mobile communications network

    佐藤拓朗, 川辺 学, 加藤俊雄, 深沢敦司

    39th IEEE Vehicular Technology conference     656 - 659  1989年05月

  • Data transmission performance in a narrow band system

    徳田清仁, 川辺 学, 佐藤拓朗

    37th IEEE Vehicular Technology conference     300 - 304  1988年05月

    CiNii

  • A new data compression system

    佐藤拓朗, 川辺 学, 島崎俊雄

    87 GROBCOM、Vol.2 of 3 、     1402 - 1405  1987年11月

  • 4800bit/s high speed voice band data and CCITT T30 facsimile transmission over cellular mobile radio system

    佐藤拓朗, 深沢敦司, 辻 健造

    5th World Telecommunication FORUM 87.2 Ⅲ     191 - 195  1987年10月

  • Adaptive error control scheme for high speed data transmission through a fading channel

    深沢敦司, 佐藤拓朗, 吉田達正, 川辺 学

    36th IEEE Vehicular Technology Conference     256 - 261  1986年05月

  • 4800bit/s high speed data transmission over cellular system

    深沢敦司, 佐藤拓朗, 徳田清仁, 徳山勝巳

    36th IEEE Vehicular Technology Conference     208 - 214  1986年05月

  • Analysis and Simulation Results of Handoff Scheme in an Infrastructure-Based Multi-Hop Network

    Kenichi Ito, Jen-Shew Shih, Takuro Sato

    Wireless Personal Multimadia Communications   Vol.1-175

▼全件表示

書籍等出版物

  • Smart Grid Standards: Specifications, Requirements, and Technologies

    Takuro Sato( 担当: 共著)

    Wily  2015年02月 ISBN: 9781118653692

  • 最新移動通信のキーテクノロジー

    佐藤拓朗, 伊藤建一

    リックテレコム  2009年02月 ISBN: 9784897978147

  • RFワールド No2

    佐藤拓朗

    CQ出版  2008年06月

  • CDMA的基礎興応用

    佐藤拓朗( 担当: 共著)

    広磁資所  2002年12月

  • OFDM技術の基礎から応用まで

    佐藤拓朗

    リアライズ  1999年11月 ISBN: 4898080197

  • CDMA技術の基礎から応用まで

    佐藤拓朗

    リアライズ  1997年12月 ISBN: 4898080030

  • 無線データ通信入門解説

    佐藤拓朗

    ST出版  1994年06月

▼全件表示

共同研究・競争的資金等の研究課題

  • 屋内において10Gbpsを超える超高速通信を可能とする第5世代移動通信システムの技術的条件等に関する調査検討(GⅣ)

    総務省 技術試験事務  総務省 技術試験事務

    研究期間:

    2017年04月
    -
    2020年03月
     

  • サービスに応じたスライス動的生成・管理機能の実証と標準化を目的とする日欧連携5G移動通信基盤テストベッドの研究開発

    総務省  総務省SCOPE サービスに応じたスライス動的生成・管理機能の実証と標準化を目的とする日欧連携5G移動通信基盤テストベッドの研究開発

    研究期間:

    2016年04月
    -
    2019年06月
     

  • IoT共通基盤技術の確立実証高効率かつセキュアなIoTデータ収集・配信ネットワーク制御技術の確立

    総務省  総務省 IoT共通基盤技術の確立実証高効率かつセキュアなIoTデータ収集・配信ネットワーク制御技術の確立

    研究期間:

    2017年04月
    -
    2019年03月
     

  • 止まらない通信網”を活用した命をつなぐ減災推進事業

    総務省  総務省 SCOPE 止まらない通信網”を活用した命をつなぐ減災推進事業

    研究期間:

    2016年04月
    -
    2018年03月
     

  • 本庄地域高度医療情報ネットワーク支援システムのための無線ATMの実用化研究

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(地域連携推進研究費)

    研究期間:

    1999年
    -
    2001年
     

    富永 英義, 佐藤 拓朗, 亀山 渉, 浦野 義頼, 西塔 隆二, 笠原 孝雄

     概要を見る

    1 研究目的 埼玉県本庄地域で実施されている「地域適合型高度情報通信サービスアプリケーションの研究開発」プロジェクトと連携し、アクセスネットワークに無線ATMを利用したネットワークを、本庄地方拠点都市地域における高度医療情報ネットワーク支援システムのインフラストラクチャとすることにより、無線ATMの実用化に関する研究を行う。
    2 研究成果の概要と今後の研究展開 これまで連携先プロジェクトでは、埼玉県本庄地域と近隣町村に対し、広域無線LANの構築と高度医療情報ネットワーク支援システムの構築を進めている。本研究では、平成11年度において、高速光無線通信システムによる無線ATMネットワークの設計検討、基礎実験、連携先研究会とのシステム環境調査などの基礎検討を行った。平成12年度は、光無線ATMネットワークの構築、連携先プロジェクトへのネットワーク接続のためのアーキテクチャ設計と、HD動画像配信システム、MPEG-4映像伝送システムを用いたアーキテクチャ確認および、連携先研究会と共同での多地点遠隔講義の実証実験を行った。平成13年度は、近隣町村の神泉村での難視聴CATVに関するコンテント伝送システム検討や、光無線ATMネットワークを含む統合広域ネットワーク上における、HD動画像配信システムとMPEG-4映像伝送システムの実証実験を通して、無線ATMが実用的であることを確認した。また、高度医療情報に間するネットワーク支援システムとサービスシステムの検討を行うと伴に、本庄地域における医療機関の設置状況調査を行い、地域全体への研究システム適用に関する検討も行った。今後は、連携先プロジェクトの福祉・医療分野での研究開発に対して、本研究で得られた研究成果を十分反映できる様な研究協力を行っていく予定である。

  • セルラ移動通信系のニューロダイナミックチャネル割当システムの研究

    日本学術振興会  科学研究費助成事業

    研究期間:

    1998年
    -
    2001年
     

    仙石 正和, 中野 敬介, 佐藤 拓朗, 岡田 和則, 篠田 庄司, 山田 吉英, 田村 裕

     概要を見る

    移動通信への需要の急激な高まりから周波数の有効利用が重要な課題となっている.この問題を解決するため,移動通信ネットワークの高度な最適化,知的制御を行う必要があるが,その際には,多くのNP完全問題を高速に解く必要が生ずる.そのため,ニューラルネット,遺伝的アルゴリズム等を用いた近似最適化手法の移動通信ネットワークの制御に対する応用は非常に重要な課題である.本研究の目的は,ニューラルネット,遺伝的アルゴリズム等を用いた高速ダイナミックチャネル割当システムを実現すること,その性能を評価することである.最近のマイクロプロセッサ技術の進歩により,複数の高速マイクロプロセッサを用いた高速ダイナミックチャネル割当システムも実現例の一つの形態として考えられる.そこで,本研究では,ニューロアルゴリズム,遺伝的アルゴリズムを基本としたマイクロプロセッサを複数用いた高速ダイナミッククチャネル割当システムの設計及び制御システムに関する検討を行い,特に並列処理,分散処理を用いた遺伝的アルゴリズムによるチャネル割当法の開発,評価を行い,その有効性を確認した.また,交通トラヒックの変動による通信トラヒックの変動を考慮したチャネル割当問題を考え,この場合のチャネル割当問題の解法を提案した.また,利用者の移動を考慮して,ダイナミックチャネル割当法が用いられているセルラシステムの理論性能評価手法を提案した.また,その他の最適化問題や基礎技術についても並行して検討を行い,様々な成果を得た

  • マルチキャリアCDMA伝送方式による放送と移動通信の無線システム技術の研究

    研究期間:

    1999年
    -
     
     

▼全件表示

Misc

  • 低遅延でインタラクティブなゼロレイテンシー映像・Somatic統合ネットワーク(1)全体概要

    甲藤二郎, 勝山裕, 佐藤俊雄, QI Xin, WEN Zheng, 金井謙治, SUN Heming, 亀山渉, 佐藤拓朗, 津田俊隆, 中村裕一, 近藤一晃, 下西慶, 小野浩司, 根波健一, 小林康雄, 森一倫, 永松衛二

    電子情報通信学会大会講演論文集(CD-ROM)   2023  2023年

    J-GLOBAL

  • Using linguistic properties of place specification for network naming to improve mobility performance

    Jairo López, Quang Ngoc Nguyen, Zheng Wen, Keping Yu, Takuro Sato

    Sensors (Switzerland)   19  2019年07月

     概要を見る

    © 2019 by the authors. Licensee MDPI, Basel, Switzerland. By considering the definitions and properties from the field of linguistics regarding place specification, a questionnaire that can be used to improve naming in networks is obtained. The questionnaire helps introduce the idea of place specification from linguistics and the concept of metric spaces into network naming schemes. The questionnaire results are used to improve the basic Information-Centric Networking (ICN) architecture’s notoriously lax network naming structure. The improvements are realized by leveraging components from the Named-Node Network Architecture, a minor ICN design, to supply the resulting network architecture with the properties the questionnaire highlights. Evaluation results from experiments demonstrate that modifying the network architecture so that the proposed questionnaire is satisfied results in achieving high mobility performance. Specifically, the proposed system can obtain mean application goodput at above 88% of the ideal result, with a delay below 0.104 s and with the network time-out Interest ratio below 0.082 for the proposed single mobile push producer, single mobile consumer scenario, even when the nodes reach the maximum tested speed of 14 m/s.

    DOI PubMed

  • Content-oriented disaster network utilizing named node routing and field experiment evaluation

    Xin Qi, Zheng Wen, Keping Yu, Kazunori Murata, Kouichi Shibata, Takuro Sato

    IEICE Transactions on Information and Systems   E102D   988 - 997  2019年05月

     概要を見る

    Copyright © 2019 The Institute of Electronics, Information and Communication Engineers. Low Power Wide Area Network (LPWAN) is designed for low-bandwidth, low-power, long-distance, large-scale connected IoT applications and realistic for networking in an emergency or restricted situation, so it has been proposed as an attractive communication technology to handle unexpected situations that occur during and/or after a disaster. However, the traditional LPWAN with its default protocol will reduce the communication efficiency in disaster situation because a large number of users will send and receive emergency information result in communication jams and soaring error rates. In this paper, we proposed a LPWAN based decentralized network structure as an extension of our previous Disaster Information Sharing System (DISS). Our network structure is powered by Named Node Networking (3N) which is based on the Information-Centric Networking (ICN). This network structure optimizes the excessive useless packet forwarding and path optimization problems with node name routing (NNR). To verify our proposal, we conduct a field experiment to evaluate the efficiency of packet path forwarding between 3N+LPWA structure and ICN+LPWA structure. Experimental results confirm that the load of the entire data transmission network is significantly reduced after NNR optimized the transmission path.

    DOI

  • A novel base-station selection strategy for cellular vehicle-to-everything (C-V2X) communications

    Qiaozhi Hua, Keping Yu, Zheng Wen, Takuro Sato

    Applied Sciences (Switzerland)   9  2019年02月

     概要を見る

    © 2019 by the authors. Cellular vehicle-to-everything (C-V2X) communication facilitates the improved safety, comfort, and efficiency of vehicles and mobility by exchanging information between vehicles and other entities. In general, only the macrocell or only the femtocell is the communication infrastructure for C-V2X. Currently, a macro-femtocell network is used as the new C-V2X networking architecture. However, there are two unresolved problems for C-V2X in macro-femtocell networks. Firstly, vehicle mobility requires the frequent switching of connections between different base stations; invalid switching results in worse communication quality. Secondly, unintelligent base station selections cause network congestion and network-load imbalance. To address the above challenges, this paper proposes a base station selection strategy based on a Markov decision policy for a vehicle in a macro-femtocell system. Firstly, we present a mechanism to predict received signal strength (RSS) for base station selection. Secondly, a comparing Markov decision policy algorithm is presented in C-V2X. To the best of our knowledge, this is the first attempt to achieve predicted RSS based on a Markov decision policy in C-V2X technology. To validate the proposed mechanism, we simulated the traditional base station selection and our proposal when the vehicle moved at different speeds. This demonstrates that the effectiveness of a traditional base station selection policy is obvious only at high speeds, and this weakness can be resolved by our proposal. Then, we compare our solution with the traditional base station selection policy. The simulation results show that our solution is effective at switching connections between base stations, and it can effectively prevent the overloading of network resources.

    DOI

  • Design and performance evaluation of content-oriented communication system for iot network: A case study of named node networking for real-Time video streaming system

    Xin Qi, Yuwei Su, Keping Yu, Jingsong Li, Qiaozhi Hua, Zheng Wen, Jairo Lopez, Takuro Sato

    IEEE Access   7   88138 - 88149  2019年01月

     概要を見る

    © 2013 IEEE. Information-Centric Networking (ICN) was born in an era that more and more users are shifting their interests to the content itself rather than the location where contents are stored. This paradigm shift in the usage patterns of the Internet, along with the urgent needs for content naming, pervasive caching, better security, and mobility support, has prompted researchers to consider a radical change to the Internet architecture. However, ICN is still in its infancy and development stage, and many issues still exist and need to be addressed. The common ICN architecture is lacking the host-centric communication ability and difficult to provide seamless mobility in current solutions. To solve this problem, our team had proposed the Named-Node Networking (3N) concept, which not only naming the content but also naming the node and it proved to have better performance of providing seamless mobility in the simulation. However, the previous contributions were limited in the 3N namespace for seamless mobility support in both producer and consumer. In this paper, we have proposed a 3N system which includes 3N naming, data delivery, mobility support, and data security. Moreover, we have created a 3N-based real-Time video streaming system to evaluate data delivery performance and mobility handoff performance. The evaluation result proofs that our system performs better than TCP video streaming in a multi-client situation and a WiFi-based handoff was demonstrated.

    DOI

  • Content-Oriented Surveillance System Based on ICN in Disaster Scenarios

    Koki Okamoto, Toru Mochida, Daichi Nozaki, Zheng Wen, Xin Qi, Takuro Sato

    International Symposium on Wireless Personal Multimedia Communications, WPMC   2018-November   484 - 489  2018年07月

     概要を見る

    © 2018 IEEE. This paper deals with an efficient image object detection method for use in a disaster prevention network that uses information-centric networking (ICN). In ICN for disaster prevention, a large number of surveillance cameras are arranged, and disaster image contents corresponding to the user&#039;s requests are distributed directly from the node attached to the surveillance camera. At this time, the name of the content requested by the user does not necessarily match the name of the image acquired by the surveillance camera. In this paper, the content requested by the user is processed and named using natural language processing (NLP). In addition, the image content from the surveillance camera is named using artificial intelligence technology. In this way, a method for improving the hit ratio between users and cameras was established. Furthermore, the volume of the interest packets decreases based on the information which area often occurs disaster. As a result, the network efficiency of ICN can be improved.

    DOI

  • AI Management System to Prevent Accidents in Construction Zones Using 4K Cameras Based on 5G Network

    Daichi Nozaki, Koki Okamoto, Toru Mochida, Xin Qi, Zheng Wen, San Hlaing Myint, Kiyohito Tokuda, Takuro Sato, Kazuhiko Tamesue

    International Symposium on Wireless Personal Multimedia Communications, WPMC   2018-November   462 - 466  2018年07月

     概要を見る

    © 2018 IEEE. Accident prevention for trucks, cranes and work vehicles at construction sites is important. Here, we use high-precision surveillance cameras with 4K cameras as IoT terminals to implement safe workplace environments. In this research, the system transmits photographic images from trucks, cranes, and other construction equipment fitted with 4K cameras at the work site to a database via 5G wireless networks, and uses AI to assess the interactions and movements of workers in the database. We introduce a system that makes it possible to avoid crashes by informing truck and crane drivers, and notifying automatic driving trucks and crane cars of that information. It is conceivable that uplink traffic could become congested due to many vehicles equipped with 4K cameras simultaneously transmitting images over the 5G uplink. Here, as a basic 5G characteristic evaluation, 4K images from trucks or cranes moving at a low speed are transmitted to the database according to moving speed and distance to the 5G terminal connecting the base station and IoT device. Based on the error environment, we report the relation with the error of the system that judges and identifies the surrounding environment using AI when video quality is deteriorated.

    DOI

  • A Novel ICN & Drone Based Emergency Information System for Disaster Area (回路とシステム)

    Wen Zheng, Zhang Di, Qi Xin, Yu Keping, Sato Takuro

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 421 ) 47 - 52  2017年01月

    CiNii

  • A Novel ICN & Drone Based Emergency Information System for Disaster Area (安全・安心な生活とICT)

    Wen Zheng, Zhang Di, Qi Xin, Yu Keping, Sato Takuro

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 422 ) 47 - 52  2017年01月

    CiNii

  • B-6-121 3N-SIMULATOR PACKAGE TRANSMISSION ON PHYSICAL NETWORK

    Qi Xin, Zhang Lu, Wen Zheng, Sato Takuro

    電子情報通信学会総合大会講演論文集   2016 ( 2 )  2016年03月

    CiNii

  • Seamless mobility in data aware networking

    Jairo E. López, M. Arifuzzaman, Li Zhu, Zheng Wen, Sato Takuro

    Proceedings of the 2015 ITU Kaleidoscope: Trust in the Information Society, K-2015 - Academic Conference    2016年01月

     概要を見る

    © 2015 International Telecommunication Union. The underlying networks (of the Internet) have been reworked to make way for new technologies, some serious inefficiencies and security problems have arisen. As a result, over the past years, fundamentally new network designs have taken shape and are being tested. In ITU Recommendation Y.3001 [1], four objectives are identified in line with the requirements for Future Network; one of them is data awareness. In ITU Recommandation Y.3033 [2], the &#039;Mobility&#039; is addressed as one of the key problem spaces of data aware networking (DAN). This paper proposes Named-Node-Networking (3N), a novel architecture for DAN. We design a simulator (nnnSIM) [3] for evaluating our proposed 3N architecture which is the second major contribution of this paper. The nnnSIM simulator is written in C++ under the ns-3 framework [4] and has been made available as open-source software for the scientific community. Considering the importance of a unique DAN architecture, we propose a study for standardization work in the ITU as an initiative which can lead to its rapid adaptation.

    DOI

  • 交通機関を活用したコンテンツ配信システム (ネットワークシステム)

    佐藤 拓朗, 朴 容震, 津田 俊隆, 後藤 滋樹, 田中 良明, 亀山 渉, 嶋本 薫, 甲藤 二郎, 市野 将嗣

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   114 ( 252 ) 93 - 97  2014年10月

     概要を見る

    今後、モバイル環境において大容量動画像コンテンツを中心にトラヒックが爆発的に増大する,膨大なトラヒックを処理するために、ネットワークとしてCDN (Contents Delivery Network)を経てネットワークのクラウド化を目的としてSDN (Software Defined Network)により仮想化ネットワークの実現を図ってきた.一方で、従来のIPネットワークのIPアドレスに依存しないネットワークとしてICN (Information Centric Network)が発表され、IPネットワークに対する優位性の検討が進められている.本論文ではICNを用いた列車内のコンテンツ配信システムとしてICNを用いて実証試験を行った結果について報告する.本研究は総務省SCOPE「先進的アプリケーション」の委託事業の協力により実証された成果である.

    CiNii

  • B-6-91 Contents hit rate evaluation of proactive cashing utilizing transport systems based on CCN

    Zhu Li, Wen Zheng, Wu Chao, Zhao Zhengge, Shen Yang, Yu Na, Sato Takuro

    電子情報通信学会総合大会講演論文集   2014 ( 2 )  2014年03月

     概要を見る

    Content Centric Network(CCN) as one of the next generation networks has the characteristic of cache storage in CCN routers which reduces congestion and latency in backbone network. This characteristic can turn into great advantage in railway scene for the large throughput such as at the train station will cause great pressure on backbone network. In this paper, we propose an content pre-fetching scheme by using CCN for railway information distribution. Simulation show that content pre-fetching scheme has better performance in the aspect of bit ratio by using same cache strategy than original CCN.

    CiNii

  • B-6-83 CCN BASED DISASTER INFORMATION SERVICE

    Wen Zheng, Zhu Li, Zhao Zhengge, Sato Takuro

    電子情報通信学会総合大会講演論文集   2014 ( 2 )  2014年03月

    CiNii

  • B-6-84 PCC: Against Cache Pollution in CCN

    Wu Chao, Zhao Zhengge, Wen Zheng, Zhu Li, Shen Yang, Na Yu, Sato Takuro

    電子情報通信学会総合大会講演論文集   2014 ( 2 )  2014年03月

     概要を見る

    The content-centric network (CCN) provides a new solution to what future network would be like. By caching named data on routers, CCN intends to realize higher speed and energy efficiency in Internet. In this paper, we propose an against-attack caching strategy-popularity comparing caching (PCC). The basic design concept is based on analysis of contents&#039; popularity. Simulation shows that PCC achieves higher hit ratio than LCE when there is no attack, and outperforms LCD and LCE under attack.

    CiNii

  • Economic Incentives for major network players in Information Centric Networking : A Game Theoretic Analysis (無線通信システム)

    Arifuzzaman M, Keping Yu, Sato Takuro

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   113 ( 456 ) 533 - 537  2014年03月

     概要を見る

    By the nature of the design architecture of Information Centric Networking (ICN), it is evident that the benefits of ICN are mostly reliant on the extensive cache structure. It is true that without some explicit monetary gain the network player will not be motivated to provide this widespread cache structure for accommodating totally new internet architecture. In this paper, we clarify the economic gain of major network players in Information Centric Networking (ICN). We assumed a realistic contend distribution model for ICN and by applying game theory, we formulate an incentive sharing mechanism among the major network players involved in the contend distribution. We also analyze the possible economic gain for the network player for Live Streaming Media broadcast in ICN architecture.

    CiNii

  • Evaluation of PCC in CCN MANET (無線通信システム)

    Chao Wu, Li Zhu, Zhengge Zhao, Wen Zheng, Sato Takuro

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   113 ( 456 ) 515 - 519  2014年03月

     概要を見る

    Content Centric Network (CCN) intends to meet the rapid growth of data delivery demand. The mobile application of CCN poses a hot topic, and Mobile Ad-hoc Network (MANET), which plays a crucial role in information propagation in post-disaster rescue, combat missions and infrastructure-less applied with CCN is suggested to be more efficient. However, situation in the mobile case is different as that of wired. In this paper, we focus on the cache characteristics of mobile CCN device. We propose a novel caching decision policy -- Popularity Compare caching (PCC). Simulation show on limited memory mobile devices, PCC outperforms LCE, and achieves higher hit ratio outperforms LCD and LCE under cache attack.

    CiNii

  • CCN Based Mobile Disaster Information Sharing System : General Talk(Theory)

    Wen Zheng, Zhu Li, Zhao Zhengge, Wu Chao, Shen Yang, Yu Na, Sato Takuro

    電子情報通信学会技術研究報告. RCS, 無線通信システム   113 ( 456 ) 521 - 522  2014年02月

     概要を見る

    The content-centric networking (CCN) has changed the method of network service design. As the next generation network, the CCN provides significant advantages over previous networking. Nowadays, most webservers still work in terms of client to server (C/S) architecture. When a large scale disaster happens, the C/S architecture will become unstable. In this paper, we proposed a disaster information sharing method based on CCN, Content-oriented network service. The terminals could share and gain information from the CCN routers without webservers. The exchange of information is between the routers and mobile terminals. Even if the connection between CCN routers and Webservers is disconnected, our system may still provide disaster information service for terminals.

    CiNii

  • BS-6-41 Performance Evaluation of Residential Energy Management algorithm in Smart Grid network(BS-6. Planning, Control and Management on Networks and Services)

    Yu Keping, Zhou Zhengyu, Paul Anup Kumar, SATO Takuro

    電子情報通信学会ソサイエティ大会講演論文集   2011 ( 2 ) "S - 110"-"S-111"  2011年08月

    CiNii

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産業財産権

  • FIB検索器、FIB検索方法、及びプログラム

    佐藤 拓朗, 文 鄭, 斉 欣

    特許権

  • コンテンツ配信システム、ネットワーク装置、及びその作動方法

    亀山 渉, 甲藤 二郎, 津田 俊隆, 佐藤 拓朗

    特許権

  • コンテンツ配信システム及び方法

    甲藤 二郎, 佐藤 拓朗, 津田 俊隆, 亀山 渉, 金井 謙治

    特許権

  • コンテンツ配信システム及び方法

    津田 俊隆, 佐藤 拓朗, 亀山 渉, 甲藤 二郎

    特許権

  • ネットワーク中継装置並びに情報提供システム及び方法

    佐藤 拓朗, 津田 俊隆, 亀山 渉, 甲藤 二郎

    特許権

  • 受信装置及び受信方法

    5846601

    佐藤 拓朗, 太田 現一郎, 江 奕, 周 振宇

    特許権

  • マルチキャリア伝送方式で送信する機能を有する複数の送信局とマルチキャリア伝送方式で受信する受信局からなる伝送装置と、それを構成する送信局及び受信局

    佐藤 拓朗, 周 振宇

    特許権

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学内研究所・附属機関兼任歴

  • 2022年
    -
    2024年

    国際情報通信研究センター   兼任研究員

特定課題制度(学内資金)

  • ICNを基本とした耐災害次世代強靭ネットワークの研究

    2014年  

     概要を見る

    次世代インターネットを用いた防災ネットワークの研究を行った。次世代インターネットはICN(InformationCentric Network)を用い、災害リア情報をエリア毎に指定し、エリア内での災害情報を収集し、自動的の公開可能なネットワーク構成を明らかにした。実システムとして簡便なネットワークを構築し、GPS機能と連携することで、ほぼリアルタイムでの災害情報ネットワークの構築を可能とした。その成果を、電子情報通信学会、安全安心特集号、論文誌へ投稿した。

  • 単一アンテナを用いた干渉除去技術による周波数有効利用技術の研究

    2009年  

     概要を見る

    概要本研究は、OFDM方式において一つのアンテナを送受信機に用いるSISO(Single Input Single Output)技術を用いて、さらに、隣接セルが同じ周波数を用いても、自局の希望信号と隣接セルの干渉信号とを分離し、自局の信号のみを検出する方式に関する研究である。本研究の成果により、一つのアンテナを用い、しかも全てのセルで同一の周波数を同時に用いることができることから、OFDM方式において周波数利用効率が最大となる通信方式を明らかにした.研究報告本研究成果は2つの分けることができる。それぞれについて述べる。(1)The Sequential Channel Estimation-Adaptive Joint Maximum A Posteriori (SCE-AJMAP)に関する研究逐次型チャネル推定は、シンボル毎にデータを更新し、高速フェージングによる希望信号と干渉信号が合成された受信信号の振幅変動をより精密に追従できることを示した.逐次型チャネル推定されたシンボル毎に適応的に同時最大事後確率を希望信号と干渉信号の両トレーニング信号も用いて適応同時最大事後確率を求める逐次型チャネル推定適応同時最大事後確率(SCE-AJMAP)復号方式を研究し、従来の同時最大事後確率(JMAP)復号器に比べて高速フェージング環境下における受信特性を大きく改善できることを示した.結果を図1に示す。干渉雑音が2dBで高速移動環境下において、14dBSINRにおいて10-3の誤り特性を可能とした。(2)The Least Mean Square-Blind Joint Maximum Likelihood Sequence Estimation (LMS-BJMLSE)Algorithmに関する研究処理遅延が低い同時最尤度推定(JMLSE:Joint Maximum Likelihood Sequence Estimation)法と最小平均二乗(LMS:Least Mean Square)法を用いた単一アンテナ干渉除去方式の研究を行った.最小二乗同時最尤推定(LMS-JMLSE)方式は、希望局からのトレーニング系列のみを用い、干渉局からの情報が必要としないブラインド方式が可能であることを示した.LMS-JMLSE方式は希望信号および干渉信号のシンボル系列候補とそれぞれのチャネル推定値を用い、希望信号と干渉信号を含むレプリカ信号を生成し、受信信号から減算することで尤度情報を得て最尤推定を行い干渉信号が未知でも希望信号を検出することでブラインド問題を解決した.また、LMS-JMLSE方式は収束が遅いサブキャリアを検出し、線形補間が行うことで、トレーニング系列の大幅な減少を可能とし、伝送効率を大幅に向上させることができる.本研究ではさらに受信ダイバシーティにも適用し高速フェージングに対する優れた耐性が得られたことを明らかにした.結果を図2に示した。干渉雑音と希望信号が同じ0dBの条件において誤り特性10-3を実現した。

  • 異種無線ネットワークのハンドオフ制御方式の研究

    2006年  

     概要を見る

    セルラーシステムと無線LANネットワークの異なるネットワーク間をハンドオフそしながら接続する方法として、移動体の位置情報と移動局間の受信電力から精度の高いハンドオフを実現する手法について研究を行い、加入者容量で20%以上の増大できることを明らかにした。また、この方式によりハンドオフ失敗確率1%以下に減少できことを明らかにした。解析には、シミュレーションと解析用いて行い、理論的にも妥当であることを示した。本研究はこれからの新しい無線システムとしてリレーネットワークについても応用ができることを明らかにした。すでに、リレーネットワーク、無線アドホックネットワークへ適用する手法についても明らかにした。