Koji YAMAMOTO


Software Radio-Based Distributed Multi-User MIMO Testbed: Towards Green Wireless Communications
Hidekazu MURATA  Susumu YOSHIDA  Koji YAMAMOTO  Daisuke UMEHARA  Satoshi DENNO  Masahiro MORIKURA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2013/01/01
Vol. E96-A  No. 1  pp. 247-254
Type of Manuscript: Special Section PAPER (Special Section on Wideband Systems)
Category: INVITED
Keyword: 
green wirelessmulti-user MIMOsoftware radiodistributed antenna systemfield experiment
  Summary |  Full Text:PDF (2.8MB)

FPS-RAM: Fast Prefix Search RAM-Based Hardware for Forwarding Engine
Kazuya ZAITSU  Koji YAMAMOTO  Yasuto KURODA  Kazunari INOUE  Shingo ATA  Ikuo OKA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2012/07/01
Vol. E95-B  No. 7  pp. 2306-2314
Type of Manuscript: PAPER
Category: Network System
Keyword: 
IP routeraddress lookupternary content addressable memory (TCAM)power consumptionfield programmable gate array (FPGA)circuit design
  Summary |  Full Text:PDF (1.5MB)

Evolutionary Game Based Access Control Protocol in Wireless Networks with Mobile Routers
Ippei AOKI  Koji YAMAMOTO  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2011/08/01
Vol. E94-B  No. 8  pp. 2225-2234
Type of Manuscript: Special Section PAPER (Special Section on Deployment and Operation of New Internet Technology: Challenges and Approaches)
Category: 
Keyword: 
mobile routerevolutionary game theorygame theoryCSMA/CA
  Summary |  Full Text:PDF (702.3KB)

Resource Reduction Method for the LTE-Advanced Uplink ACK/NACK Signal and SR
Seigo NAKAO  Kenji TAKAGI  Masaru FUKUOKA  Daichi IMAMURA  Hidekazu MURATA  Koji YAMAMOTO  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2011/01/01
Vol. E94-B  No. 1  pp. 364-367
Type of Manuscript: LETTER
Category: Terrestrial Wireless Communication/Broadcasting Technologies
Keyword: 
LTE-Advancedspace orthogonal resource transmit diversityphase rotationACK/NACK signalscheduling request
  Summary |  Full Text:PDF (275.4KB)

Potential Game Approach for Spectrum Sharing in Distributed Cognitive Radio Networks
I Wayan MUSTIKA  Koji YAMAMOTO  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2010/12/01
Vol. E93-B  No. 12  pp. 3284-3292
Type of Manuscript: Special Section PAPER (Special Section on Wireless Distributed Networks)
Category: 
Keyword: 
spectrum sharinginterference managementcognitive radiogame theorypotential game
  Summary |  Full Text:PDF (779.2KB)

Wireless Distributed Network: For Flexible Networking and Radio Resource Management
Seiichi SAMPEI  Kei SAKAGUCHI  Shinsuke IBI  Koji YAMAMOTO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2010/12/01
Vol. E93-B  No. 12  pp. 3218-3227
Type of Manuscript: Special Section PAPER (Special Section on Wireless Distributed Networks)
Category: INVITED
Keyword: 
wireless distributed networkheterogeneous networkautonomous distributed networkscognitive radiocooperative transmissionradio resource management
  Summary |  Full Text:PDF (1.3MB)

A New TCAM Architecture for Managing ACL in Routers
Haesung HWANG  Shingo ATA  Koji YAMAMOTO  Kazunari INOUE  Masayuki MURATA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2010/11/01
Vol. E93-B  No. 11  pp. 3004-3012
Type of Manuscript: PAPER
Category: Network
Keyword: 
Access Control List (ACL)hardware costIP routerprefix expansionTernary Content Addressable Memory (TCAM)
  Summary |  Full Text:PDF (1.6MB)

FPGA Implementation of STBC Based Cooperative Relaying System
Hidekazu MURATA  Yuji OISHI  Koji YAMAMOTO  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2010/08/01
Vol. E93-B  No. 8  pp. 1988-1992
Type of Manuscript: Special Section PAPER (Special Section on Implementation, Experiments, and Practice for Ad Hoc and Mesh Networks)
Category: 
Keyword: 
multi-hop wireless networkscooperative relayinglaboratory experimentsFPGA implementation
  Summary |  Full Text:PDF (923.8KB)

Impact and Use of the Asymmetric Property in Bi-directional Cooperative Relaying under Asymmetric Traffic Conditions
Takaaki SAEKI  Koji YAMAMOTO  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2010/08/01
Vol. E93-B  No. 8  pp. 2126-2134
Type of Manuscript: PAPER
Category: Wireless Communication Technologies
Keyword: 
cooperative relayingasymmetric trafficoptimal relay positionopportunistic scheduling
  Summary |  Full Text:PDF (826.6KB)

Cell Edge Capacity Improvement by Using Adaptive Base Station Cooperation in Cellular Networks with Fractional Frequency Reuse
Liang XU  Koji YAMAMOTO  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2010/07/01
Vol. E93-B  No. 7  pp. 1912-1918
Type of Manuscript: PAPER
Category: Wireless Communication Technologies
Keyword: 
base station cooperationcell edgefractional frequency reuseinter-cell interference
  Summary |  Full Text:PDF (1MB)

Channel-Gain-Based Transmission Scheduling for Cooperative Relaying
Naotaka SHIBATA  Koji YAMAMOTO  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2010/03/01
Vol. E93-B  No. 3  pp. 776-779
Type of Manuscript: LETTER
Category: Terrestrial Radio Communications
Keyword: 
cooperative relayingtransmission schedulingspectral efficiency
  Summary |  Full Text:PDF (227.7KB)

Capacity Analysis of Cooperative Relaying Networks with Adaptive Relaying Scheme Selection
Kunihiko TESHIMA  Koji YAMAMOTO  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2009/12/01
Vol. E92-B  No. 12  pp. 3744-3752
Type of Manuscript: PAPER
Category: Network
Keyword: 
cooperative relayingmultihopspectral efficiencyadaptive controlgame theory
  Summary |  Full Text:PDF (527.8KB)

Performance Improvement of Wireless Mesh Networks by Using a Combination of Channel-Bonding and Multi-Channel Techniques
Liang XU  Koji YAMAMOTO  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2008/10/01
Vol. E91-B  No. 10  pp. 3103-3112
Type of Manuscript: Special Section PAPER (Special Section on Next-Generation Mobile Multimedia Communications)
Category: 
Keyword: 
IEEE 802.11nchannel-bondingmulti-channelCSMA/CAwireless mesh network
  Summary |  Full Text:PDF (553.1KB)

Spectral Efficiency of Fundamental Cooperative Relaying in Interference-Limited Environments
Koji YAMAMOTO  Hirofumi MARUYAMA  Takashi SHIMIZU  Hidekazu MURATA  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2008/08/01
Vol. E91-B  No. 8  pp. 2674-2682
Type of Manuscript: PAPER
Category: Terrestrial Radio Communications
Keyword: 
cooperative relayingmultihoparea spectral efficiencybandwidth efficiency
  Summary |  Full Text:PDF (680.4KB)

Interference Information Based Power Control for Cognitive Radio with Multi-Hop Cooperative Sensing
Youngjin YU  Hidekazu MURATA  Koji YAMAMOTO   Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2008/01/01
Vol. E91-B  No. 1  pp. 70-76
Type of Manuscript: Special Section PAPER (Special Section on Cognitive Radio and Spectrum Sharing Technology)
Category: Spectrum Sensing
Keyword: 
cognitive radiocooperative sensingshadowinginterference informationmulti-hop transmission
  Summary |  Full Text:PDF (692.7KB)

Optimum Practical Design of Distributed and Asynchronous Power Control for Wireless Networks with Shared Bands
Stepan KUCERA  Koji YAMAMOTO  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2007/07/01
Vol. E90-A  No. 7  pp. 1261-1270
Type of Manuscript: Special Section PAPER (Special Section on Multi-dimensional Mobile Information Networks)
Category: 
Keyword: 
cognitive radioad hoc networkspower controldistributedasynchronousequilibriumfrequency band sharing
  Summary |  Full Text:PDF (492.7KB)

Tradeoff between Area Spectral Efficiency and End-to-End Throughput in Rate-Adaptive Multihop Radio Networks
Koji YAMAMOTO  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2005/09/01
Vol. E88-B  No. 9  pp. 3532-3540
Type of Manuscript: Special Section PAPER (Special Section on Advances in Ad Hoc Mobile Communications and Networking)
Category: 
Keyword: 
multihop radio networksarea spectral efficiencybandwidth efficiencyrate adaptation
  Summary |  Full Text:PDF (481.6KB)

Game-Theoretic Approach to Capacity and Stability Evaluations of Decentralized Adaptive Route Selections in Wireless Ad Hoc Networks
Koji YAMAMOTO  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2005/03/01
Vol. E88-B  No. 3  pp. 1009-1016
Type of Manuscript: Special Section PAPER (Special Section on Ubiquitous Networks)
Category: Network
Keyword: 
ad hoc networksdecentralized controlgame theorynetwork capacityrouting
  Summary |  Full Text:PDF (428.1KB)

Analysis of Reverse Link Capacity Enhancement for CDMA Cellular Systems Using Two-Hop Relaying
Koji YAMAMOTO  Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2004/07/01
Vol. E87-A  No. 7  pp. 1712-1719
Type of Manuscript: Special Section PAPER (Special Section on Multi-dimensional Mobile Information Networks)
Category: Reverse Link Capacity for CDMA Cellular
Keyword: 
two-hop relayingmultihop cellular systemsCDMA cellular systemscapacity enhancement
  Summary |  Full Text:PDF (639.1KB)

Fault-Tolerant Graphs for Hypercubes and Tori*
Toshinori YAMADA  Koji YAMAMOTO  Shuichi UENO 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 1996/08/20
Vol. E79-D  No. 8  pp. 1147-1152
Type of Manuscript: Special Section PAPER (Special Issue on Architectures, Algorithms and Networks for Massively Parallel Computing)
Category: Fault Diagnosis/Tolerance
Keyword: 
hypercubestoriedge-fault-tolerant graphsmatric graphserror-correcting binary linear codes
  Summary |  Full Text:PDF (507.7KB)