Updated on 2025/01/19

写真a

 
TAKAHATA, Fumio
 
Affiliation
Faculty of Science and Engineering
Job title
Professor Emeritus
Degree
工学博士 ( 早稲田大学 )
Doctor of Engineering
博士(工学) ( 早稲田大学 )

Research Experience

  • 1988
    -
     

    Professor, School of Science and Engineering, Waseda University

  • 1974
    -
    1988

    KDD R&D Laboratories, Researcher

Education Background

  •  
    -
    1974

    Waseda University   Graduate School of Science and Engineering   Major in Electrical Engineering  

  •  
    -
    1972

    Waseda University   School of Science and Engineering   Department of Electronics and Communication Engineering  

Professional Memberships

  •  
     
     

    Institute of Image, Information and Television Engineers (ITE)

  •  
     
     

    Institute of Image Information and Television Engineers (ITE)

  •  
     
     

    Institute of Electrical and Electronics Engineers (IEEE)

  •  
     
     

    Institute of Electronics, Information and Communication Engineers (IEICE)

  •  
     
     

    Institute of Electronics, Information and Communication Engineers (IEICE)

Research Interests

  • Wireless Communications, Digital Signal Processing, Telecommunication Engineering

Awards

  • 「電波の日」総務大臣表彰

    2017.06  

  • 電子情報通信学会 通信ソサイエテイ 優秀論文賞

    2017.05  

  • 日本放送協会 放送文化賞

    2016.03  

  • 日本ITU協会賞 功績賞

    2010.05  

  • 「平成20年度情報化促進貢献個人」総務大臣表彰「情報化促進部門」

    2008.10  

▼display all

 

Papers

  • On Reduction of Computational Complexity in MLD by applying Search Algorithms

    Ken Nikaido, Akira Kato, Fumio Takahata

    Proceedings of the 2017 IEICE General Conference   B-5-3  2017.03  [Refereed]

  • On Computational Complexity in Lattice Reduction-Sphere Encoding-Vector Perturbation

    Akira Kato, Fumio Takahata

    Proceedings of the 2017 IEICE General Conference   B-5-41  2017.03  [Refereed]

  • An Adaptive Switching Scheme of OFDM Channel Estimation Direction based on Log Likelihood Ratio

    Futoshi Fukuda, Fumio Takahata

    Proceedings of the 2017 IEICE General Conference   B-5-72  2017.03  [Refereed]

  • On Bit Error Performance of Polar Codes over Additive White Gaussian Noise Channels

    Masaaki Ito, Fumio Takahata

    Proceedings of the 2016 Communications Society, IEICE Conference   B-5-17  2016.09  [Refereed]

  • An Application of Sorted QR Detection to LR-SE-VP(Lattice Reduction-Sphere Encodhing-Vector Perturbation)

    Akira Kato, Fumio Takahata

    Proceedings of the 2016 Communications Society, IEICE Conference   B-5-41  2016.09  [Refereed]

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Books and Other Publications

  • ディジタル無線通信入門

    髙畑文雄, 前原文明, 笹森文仁

    培風館  2002.06 ISBN: 9784563014872

  • 信号表現の基礎(CD-ROM付)

    髙畑文雄

    社団法人電子情報通信学会  1998.09 ISBN: 4885521556

  • 宇宙技術入門

    髙畑文雄, 森英彦, 池内了, 輿石肇, 戸田勧, 新田慶治

    オーム社  1994.09 ISBN: 4274022668

Research Projects

  • New Generation Satellite Network and Inter-university System

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research

    Project Year :

    1994
     
     
     

    TAKAHATA Fumio, PARK Y., LEE C., LEE J., TANAKA Y., ONOZATO K., TOMINAGA H., KOMATSU N.

     View Summary

    The appearance of advanced satellites with high power and the cost reduction of earth stations enabled universities to conduct experiments using actual satellites. Taking account of this situation, the University^<, >s Joint Study Group for Digital Satellite Communications (UnSAT JSG) has been established, in which more than forty universities in Japan, two universities each in Korea and China join and about thirty universities are actually carrying out experiments using their own earth stations via Ku-band satellite. The experiments cover a variety of study fields such as radio propagation characteristics, communications scheme, network structure between universities, transmission and security of video, image and computer data. Considering that satellites have an inherent potential to provide borderless communications, it is expected by the international cooperation that the experiments via satellite will widely spread over the Asia-Pacific region in the near future

  • Study on Spread Spectrum Packet Communications

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research

    Project Year :

    1993
    -
    1994
     

    TAKAHATA Fumio

     View Summary

    A spread ALOHA system using a unified spread spectrum code is discussed in terms of its performance, design and transmission efficiency. The system is outlined and then the bit error performance under two conditions is derived by a theoretical analysis and an approximate method. The comparison it with the results obtained by means of computer simulation indicates that the theoretical results coincide perfectly with the simulated ones and that the approximayte results coincide with the simulated results in the low E_b/N_0 range. A demondulator is designed focussing on symbol timing recovery and carrier recovery. It is proposed that the provision of a short preamble enables to apply a synchronous cyclic addition to these recoveries. It is concluded as a result of performance evaluation concerming symbol timing detection and carrier offset estimation that the proposed scheme improves the performance remarkably. The transmission efficiency obtained in the spread ALOHA system is derived for three cases. Comparing quantitatively the transmission efficiency in the first case with that of the conventional slotted ALOHA system under the condition at the same frequency bandwidth, it is concluded that the spread ALOHA system gives a good performance with the lower transmitting power compared with that of the slotted ALOHA system. As for the other two cases, the system using a unified spread spectrum code is compared with that using different spread spectrum codes in terms of transmission efficiency and it becomes obvious that the former system provides better performance for the long packet length than the latter one. Finally it is proposed to realize a spread-ALOHA system by using a chirp signal. Correlation process using the chirp matched filter is theoretically described at first and signal processings to be performed in the receiving side are clarified, in particular focussing on the block demodulator. The quantitative evaluation under various conditions is discussed concerning bit error rate performance obtained by means of computer simulation

  • Syudy on Frame Synchronization Methods for Digital Satellite Communications System

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research

    Project Year :

    1990
    -
    1991
     

    TAKAHATA Fumio

     View Summary

    Frame synchronization is an essential function for providing digital transmission services in digital satellite communications systems. It consists of a detection of frame synchronization pattern called "Unique Word (UW)", and an establishment of synchronization by detecting UWs consecutively. The UW detection in the receiving side is realized based on Euclidian distance between received signal vector and UW vector in multi-dimentional space, the dimension of which coincides with the length of UW. An application of quantized soft-decision data to UW detection is discussed from the practical point of view, and a theoretical and experimental approaches are established for obtaining a variety of UW detection characteristics. The obtained performance such as unique word missed, false detections and so on is quantitatively evaluated, compared with that of conventional hard-decision data and non-quantized soft-decision data. It is concluded from the quantitative evaluation that the application of quantized soft-decision data has potential to realize effectively the UW detection complying with design objective. With respect to the frame synchronization, a theoretical approach is established for calculating a variety of frame synchronization characteristics from those of UW detection. It becomes obvious from the quantitative evaluation that the UW detection using soft-decision data provides better performance on the criteria of reframe time and sync loss detection & reframe time in the low C/N condition, compared to the use of hard-decision and non-quantized soft-decision data

  • 次世代衛星ネットワ-クシステムと大学間共同利用に関する総合的研究

     View Summary

    通信と放送はそれを実現する基本的な技術は同類のものであり共通な機能も多くあったが、施設や機器の運用制度や利用形態の差が個々の技術の差となって現れた。このことにより通信衛星と放送衛星の区別が生じ、技術開発のプロセスとその運用制度も区別されたものとして発達しているが、技術開発の本質はこれらの運用制度の壁を越え、コンピュ-タと映像の融合とともに放送に通信のサ-ビス機能の区別が全く意味をなさなくなってきている。衛星を用いた媒体においても通信と放送とコンピュ-タを統合したサ-ビス機能の実現が予想される。この研究の主題である「次世代衛星ネットワ-クシステム」とは、家庭やオフィスの端末はもとより、自動車や飛行機等の移動体や、人の携帯する端末に対し、高詳細な画像や音声、デ-タを含んだ情報を、従来の通信的な機能と放送的な機能の両方を実現しうる衛星によるネットワ-クシステムのことである。このような研究開発は、従来、供給者側の視点から行なわれている。すなわち、NTTやNHKなどの事業者の立場での開発が先行しており、またこれを制度的に規制し、バックアップする郵政省等による行政指導によって行なわれている。このことは、利用者側の視点による技術開発がともすると蔑ろにされたために、真に利用者の利便性を重視したシステム開発のための基礎研究の遅れを生む結果となった。これらの歪みを正すために利用者側の視点で基礎研究を行なうことが重要であり、文部省科学研究費補助金重点領域研究の必要性がある。すなわち、本研究は大学を中心とした教育・研究の場において必要である情報通信のインフラストラクチャを構築するための基礎研究を行なうに当たり、何を研究すべきかを調査した結果である