All posts by d-wise-lab

Prof. Chen visited our laboratory.

Prof. Yougan Chen, Ph.D visited our laboratory and had discussions with Prof. Ishibashi on 1st June.

Prof. Chen published the paper entitled “OFDM-Modulated Dynamic Coded Cooperation in Underwater Acoustic Channels” in IEEE Journal of Oceanic Engineering which was inspired by Prof. Ishibashi’s paper on dynamic coded cooperation.

[Prof. Chen’s website]


Our member, Hiroki Kawabata, gave presentation titled “Analysis of Energy Harvesting Relay Selection Using Channel Distribution Information” at IEICE SR, Akashi, Japan.


“チャネル分布情報を用いたエナジーハーベスティング中継端末選択法の解析”,川畑大樹,ヴッパラ サティアナラヤナ,アブレウ ジュゼッペ,石橋功至

Prof. Abreu: New visiting professor.

Prof. Giuseppe Abreu from Jacobs University Bremen, Germany, is now visiting our laboratory.

He will stay until the end of August and we have started a joint research project about the secrecy capacity.

2014 IEICE RCS Active Research Award

Naoki Takeishi, an alumnus of our group, won the 2014 IEICE RCS Active Research Award.

石橋研究室の卒業生である武石直樹君が,2014年度電子情報通信学会 無線通信システム(RCS)研究会活動奨励賞を受賞しました.



English follows Japanese.

2015年3月に滋賀県立命館大学で開催されたIEICE 2015年総合大会において、修士1年川畑大樹君、尾形 駿君が下記のテーマで発表を行いました。

“チャネル分布情報を用いたエナジーハーベスティング中継端末の選択法に関する一検討”,川畑大樹,Abreu Giuseppe,Vuppala Satyanaranaya,石橋功至

“Frameless ALOHAにおけるターゲット重みの最適化”,尾形駿,ジュゼッペ  アブレウ,石橋功至

Our members, Hiroki Kawabata and Shun Ogata gave presentations titled “A study on energy harvesting relay selection using channel distribution information”  and “Optimization of the target degree of frameless ALOHA,” respectively at the 2015 IEICE General Conference.


English follows Japanese.

2015年3月に東京工業大学で開催されたRCS研究会において、修士2年 武石直樹君、修士1年 尾形 駿君が下記のテーマで発表を行いました。

“分散多次元空間結合Repeat-Accumulate符号”, 武石直樹, 石橋功至, アブレウ ジュゼッペ

“フレームレスALOHAにおけるターゲット重み分布の密度発展法を用いた最適化”, 尾形 駿, アブレウ ジュゼッペ, 石橋功至


Our members, Naoki Takeishi and Shun Ogata gave presentations about distributed multi-dimensional spatially coupled Repeat-Accumulate code and optimization of target degree distribution using density evolution for frameless ALOHA, respectively at IEICE RCS, Tokyo, Japan.

Our paper has been accepted to IEEE WCNC’15.

Our paper entitled “spatially-coupled repeat accumulate coded cooperation” has been accepted to IEEE WCNC’15 will be held at New Orleans, LA.

The program of Track1 (PHY and Fundamentals) is available at the following website:

The paper proposes the effective technique to simultaneously obtain the diversity and coding gain even when both the number of users and the length of information packets are limited. The proposed approach significantly improves the decoding performance compared with conventional cooperative techniques.

Special Guest Lecture @ Jacobs University Bremen

Professor Ishibashi gave a special guest lecture about RF energy harvesting and cooperative communications at Jacobs University Bremen in Bremen, Germany on Dec 8, 2014.

Abstract: In this talk, we provide an overview of radio frequency (RF) energy harvesting technology, which scavenges the energy from ambient radio signals. As an example of wireless-powered cooperative diversity, we introduce dynamic-harvest-and-forward (DHF) cooperation which enables to obtain diversity gain with consuming neither extra energy nor extra bandwidth by exploiting the relay’s proximity advantage over the destination. We analyze the DHF cooperation from the aspect of diversity-multiplexing tradeoff (DMT) and prove that it can achieve diversity order of two. Also, some open issues regarding cooperative diversity with RF energy harvesting are presented.

Further details can be found in the following link: