研究者詳細 - 山里　敬也

論文 - 山里　敬也

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符号化OFDM通信方式における複数シンボルマッピングによる最大瞬時電力抑圧手法査読有り

原田政明, 山里敬也, 岡田啓, 片山正昭, 小川明

電子情報通信学会論文誌 J86-A 巻 ( 10 ) 頁： 1058-1067 2003年10月

基地局ダイバシチを用いたTCPによる無線インターネット接続に関する一検討

内藤克浩, 岡田啓, 山里敬也, 片山正昭

電子情報通信学会ネットワークシステム研究会 103 巻 ( 204 ) 頁： 31 - 36 2003年7月

Performance Improvement for Coded OFDM Systems with Adaptive Interleaving in Frequency Selective Fading Channel 査読有り

M. Harada, T. Yamazato, H. Okada, M. Katayama, A. Ogawa

電子情報通信学会論文誌 E86-A 巻 ( 6 ) 頁： 1541-1549 2003年6月

記述言語：英語掲載種別：研究論文（学術雑誌）

In an attempt to improve the performance under frequency selective fading environment, we develope in this paper an orthogonal frequency division multiplex (OFDM) system in which adaptive interleaving is applied. The adaptive interleaving is a method that assigns symbols adaptively to the subcarriers in order to cope with frequency selective fading based on a channel state information (CSI) sent back from the reception end. The concept of adaptive interleaving is to maximize a free Euclidean distance in the limited interleave size. In this paper, we extend the method by an introduction of bit interleaving and multiple trellis coded modulation (MTCM). MTCM assigns two or more symbols to one trellis branch and shows good performance in frequency selective fading. If we could assign those set of symbols with an aid of the adaptive interleaving, the performance improvement can be expected. Another improvement method considered in this paper is the use of bit interleaving. The bit interleaving techniques randomize the effect of channel more efficiently compared to the case of symbols interleaving. Thus the further performance improvement is expected. One draw back is that since the interleaving process is done in bit level, bit interleaving can not be applied to TCM nor MTCM. In this paper, we mainly focus on adaptive bit and symbol interleaving and discuss the performance from the point of interleaving effect, and the error correcting code (convolutional code and MTCM).

Performance improvement for coded OFDM systems with adaptive interleaving in frequency selective fading channel 査読有り

Harada M, Yamazato T, Okada H, Katayama M, Ogawa A

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES E86A 巻 ( 6 ) 頁： 1541 - 1549 2003年6月

Performance Improvement for Coded OFDM Systems with Adaptive Interleaving in Frequency Selective Fading Channel 査読有り

Harada M.

IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E86-A 巻 ( 6 ) 頁： 1541 - 1549 2003年6月

Performance Improvement for Coded OFDM Systems with Adaptive Interleaving in Frequency Selective Fading Channel 査読有り

M. Harada, T. Yamazato, H. Okada, M. Katayama, A. Ogawa

IEICE Transactions on Fundamentals E86-A 巻 ( 6 ) 頁： 1541-1549 - 1549 2003年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：一般社団法人電子情報通信学会

In an attempt to improve the performance under frequency selective fading environment, we develop in this paper an orthogonal frequency division multiplex (OFDM) system in which adaptive interleaving is applied. The adaptive interleaving is a method that assigns symbols adaptively to the subcarriers in order to cope with frequency selective fading based on a channel state information (CSI) sent back from the reception end. The concept of adaptive interleaving is to maximize a free Euclidean distance in the limited interleave size. In this paper, we extend the method by an introduction of bit interleaving and multiple trellis coded modulation (MTCM). MTCM assigns two or more symbols to one trellis branch and shows good performance in frequency selective fading. If we could assign those set of symbols with an aid of the adaptive interleaving, the performance improvement can be expected. Another improvement method considered in this paper is the use of bit interleaving. The bit interleaving techniques randomize the effect of channel more efficiently compared to the case of symbols interleaving. Thus the further performance improvement is expected. One draw back is that since the interleaving process is done in bit level, bit interleaving can not be applied to TCM nor MTCM. In this paper, we mainly focus on adaptive bit and symbol interleaving and discuss the performance from the point of interleaving effect, and the error correcting code (convolutional code and MTCM).

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A-5-15 DS-CDMA 方式の周波数領域での線形フィルタリングに関する一検討査読有り

竹内裕志, 山里敬也, 岡田啓, 片山正昭

電子情報通信学会総合大会講演論文集 2003 巻頁： 154 2003年3月

A Study on Turbo Soft-Decision Decoding for Hard-Detected Optical Communication signals 査読有り

ZHENG Chen, YAMAZATO Takaya, OKADA Hikaru, KATAYAMA Masaaki, OGAWA Akira

IEICE Trans. Communication, B 86 巻 ( 3 ) 頁： 1022 - 1030 2003年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：The Institute of Electronics, Information and Communication Engineers

We propose a method to realize soft-derision decoding for hard-detected signals. In this paper, a novel concept is introduced as "error-deleeled reliability." The method is very useful for optical fiber communications (OFC) as hard detection is the only detection method for the OFC systems. We demonstrate our proposed method using the turbo code in which soft information is required for decoding. As a result, the simulation shows slight difference in the range of moderate to high signal-to-noise ratio between the proposed decoding scheme and the conventional turbo decoding scheme. Moreover, the bit error rate of If 10^<〜11> can be achieved by serial concatenation of a ReedSolomon code and a turbo code for Q-factor lower than 8.0dB with a bandwidth expansion ratio of 33.3%.

CiNii Research

A Study on Turbo Soft-Decision Decoding for Hard Detected Optical Communication Signals 査読有り

C. Zheng, T. Yamazato, H. Okada, M. Katayama, A. Ogawa

電子情報通信学会論文誌 E86-B 巻 ( 3 ) 頁： 1022-1030 2003年3月

記述言語：英語掲載種別：研究論文（学術雑誌）

We propose a method to realize soft-decision decoding for hard-detected signals. In this paper, a novel concept is introduced as error-detected reliability. The method is very useful for optical fiber communications (OFC) as hard detection is the only detection method for the OFC systems. We demonstrate our proposed method using the turbo code in which soft information is required for decoding. As a result, the simulation shows slight difference in the range of moderate to high signal-to-noise ratio between the proposed decoding scheme and the conventional turbo decoding scheme. Moreover, the bit error rate of 10-11 can be achieved by serial concatenation of a Reed-Solomon code and a turbo code for Q-factor lower than 8.0 dB with a bandwidth expansion ratio of 33.3%.

Noise analysis on wide-band PLC with high sampling rate and long observation time 査読有り

Y. Hirayama, H. Okada, T. Yamazato and M. Katayama

7th International Symposium on Power-Line Communications and Its Applications 頁： 142-147 2003年3月

記述言語：英語

This manuscript reports the results of the measurement of wide-band PLC noise with high speed (50MHz) sampling and long (10.4s) observation duration. The measured noise is divided in frequency, and stochastic properties of the noise waveforms in each frequency bands, such as autocorrelations, probability density functions, and correlation coefficients between noise waveforms of different frequency bands are discussed. Cyclostationary features of the noise in each band is confirmed. It is found that the amplitude distribution in each band is different, and that Gaussian noise model is not a good approximation in higher frequency bands.

Soft-Decision Decoding of Low-Density Parity-Check Codes for Hard-Detected Optical Communication Signals 査読有り

C. Zheng, T. Yamazato, H. Okada, M. Katayama, A. Ogawa

電子情報通信学会論文誌 E86-B 巻 ( 3 ) 頁： 1132-1135 2003年3月

記述言語：英語掲載種別：研究論文（学術雑誌）

A soft-decision decoding scheme of low-density parity-check codes (LDPC) is proposed for hard-detected signals of optical fiber communication (OFC) systems. Based on the error detection, the proposed scheme converts the received hard-decision into soft reliability for the input of the LDPC decoder, and soft-decision decoding is performed. Simulation results under OFC channels are shown and superior performance is obtained by using the proposed decoding scheme of the LDPC codes.

A Study on Turbo Soft-Decision Decoding for Hard Detected Optical Communication Signals 査読有り

C. Zheng, T. Yamazato, H. Okada, M. Katayama, A. Ogawa

IEICE Transactions on Communications E86-B 巻 ( 3 ) 頁： 1022-1030 - 1135 2003年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：一般社団法人電子情報通信学会

A soft-derision decoding scheme of low-density parity-check codes (LDPC) is proposed for hard-detected signals of optical fiber communication (OFC) systems. Based on the error detection, the proposed scheme converts the received hard-decision into soft reliability for the input of the LDPC decoder, and soft-decision decoding is performed. Simulation results under OFC channels are shown and superior performance is obtained by using the proposed decoding scheme of the LDPC codes.

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A study on turbo soft-decision decoding for hard-detected optical communication signals 査読有り

Zheng C, Yamazato T, Okada H, Katayama M, Ogawa A

IEICE TRANSACTIONS ON COMMUNICATIONS E86B 巻 ( 3 ) 頁： 1022 - 1030 2003年3月

A study on turbo soft-decision decoding for hard-detected optical communication signals 査読有り

Zheng C., Yamazato T., Okada H., Katayama M., Ogawa A.

IEICE Transactions on Communications E86-B 巻 ( 3 ) 頁： 1022 - 1030 2003年3月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：IEICE Transactions on Communications

We propose a method to realize soft-decision decoding for hard-detected signals. In this paper, a novel concept is introduced as "error-detected reliability." The method is very useful for optical fiber communications (OFC) as hard detection is the only detection method for the OFC systems. We demonstrate our proposed method using the turbo code in which soft information is required for decoding. As a result, the simulation shows slight difference in the range of moderate to high signal-to-noise ratio between the proposed decoding scheme and the conventional turbo decoding scheme. Moreover, the bit error rate of 10-11 can be achieved by serial concatenation of a Reed-Solomon code and a turbo code for Q-factor lower than 8.0 dB with a bandwidth expansion ratio of 33.3%.

Scopus

Soft-decision decoding of low-density parity-check codes for hard-detected optical communication signals 査読有り

Zheng C, Yamazato T, Okada H, Katayama M, Ogawa A

IEICE TRANSACTIONS ON COMMUNICATIONS E86B 巻 ( 3 ) 頁： 1132 - 1135 2003年3月