Koji YAMAMOTO


Knowledge-Based Reestablishment of Primary Exclusive Region in Database-Driven Spectrum Sharing
Shota YAMASHITA Koji YAMAMOTO Takayuki NISHIO Masahiro MORIKURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2016/09/01
Vol. E99-B  No. 9  pp. 2019-2027
Type of Manuscript:  Special Section PAPER (Special Section on Integration Technologies of Ambient Intelligence and Sensor Networks)
Category: 
Keyword: 
5Gcognitive radiospectrum sharingdatabasestochastic geometry
 Summary | Full Text:PDF(1.5MB)

Self-Organization of Coverage of Densely Deployed WLANs Considering Outermost APs without Generating Coverage Holes
Shotaro KAMIYA Keita NAGASHIMA Koji YAMAMOTO Takayuki NISHIO Masahiro MORIKURA Tomoyuki SUGIHARA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2016/09/01
Vol. E99-B  No. 9  pp. 1980-1988
Type of Manuscript:  Special Section PAPER (Special Section on Integration Technologies of Ambient Intelligence and Sensor Networks)
Category: 
Keyword: 
coverage adaptationIEEE 802.11 WLANtransmission power controlarea coverage holecoverage boundary
 Summary | Full Text:PDF(1.6MB)

Proactive Handover Based on Human Blockage Prediction Using RGB-D Cameras for mmWave Communications
Yuta OGUMA Takayuki NISHIO Koji YAMAMOTO Masahiro MORIKURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2016/08/01
Vol. E99-B  No. 8  pp. 1734-1744
Type of Manuscript:  Special Section PAPER (Special Section on Advanced Information and Communication Technologies and Services in Conjunction with Main Topics of APCC2015)
Category: Terrestrial Wireless Communication/Broadcasting Technologies
Keyword: 
mmWave communicationshuman blockageRGB-D cameraproactive handover
 Summary | Full Text:PDF(2.1MB)

Rate Adaptation Based on Exposure Assessment Using Rectenna Output for WLAN Station Powered with Microwave Power Transmission
Shota YAMASHITA Koichi SAKAGUCHI Yong HUANG Koji YAMAMOTO Takayuki NISHIO Masahiro MORIKURA Naoki SHINOHARA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2015/09/01
Vol. E98-B  No. 9  pp. 1785-1794
Type of Manuscript:  Special Section PAPER (Special Section on Emerging Technologies on Ambient Sensor Networks toward Future Generation)
Category: 
Keyword: 
wireless local area networkrate adaptationmicrowave power transmissionrectenna
 Summary | Full Text:PDF(3.6MB)

A Comprehensive Survey of Potential Game Approaches to Wireless Networks
Koji YAMAMOTO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2015/09/01
Vol. E98-B  No. 9  pp. 1804-1823
Type of Manuscript:  INVITED SURVEY PAPER
Category: 
Keyword: 
potential gamegame theoryradio resource managementchannel assignmenttransmission power control
 Summary | Full Text:PDF(1.1MB)

An Iterative MIMO Receiver Employing Virtual Channels with a Turbo Decoder for OFDM Wireless Systems
Akihito TAYA Satoshi DENNO Koji YAMAMOTO Masahiro MORIKURA Daisuke UMEHARA Hidekazu MURATA Susumu YOSHIDA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2015/05/01
Vol. E98-B  No. 5  pp. 878-889
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
multiple-input multiple-outputvirtual channelsoft-input soft-outputlog likelihood ratioiterative scheme
 Summary | Full Text:PDF(1.5MB)

A Camera and LED-Based Medium Access Control Scheme for Wireless LANs
Ryo NISHIOKA Takayuki NISHIO Masahiro MORIKURA Koji YAMAMOTO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2015/05/01
Vol. E98-B  No. 5  pp. 917-926
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
WLANvisual MIMOmedium access controlCSMA/CAquality of experienceoptical camera communications
 Summary | Full Text:PDF(1.7MB)

Hybrid Station Aided Coexistence Scheme between Wireless PANs and Wireless LAN
Fumihiro INOUE Takayuki NISHIO Masahiro MORIKURA Koji YAMAMOTO Fusao NUNO Takatoshi SUGIYAMA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2015/02/01
Vol. E98-A  No. 2  pp. 578-588
Type of Manuscript:  Special Section PAPER (Special Section on Wideband Systems)
Category: 
Keyword: 
coexistenceIEEE 802.15.4IEEE 802.11ZigBeeWLANWPANWSNQoS
 Summary | Full Text:PDF(2.2MB)

Differential Game-Theoretic Analysis on Information Availability in Decentralized Demand-Side Energy Management Systems
Ryohei ARAI Koji YAMAMOTO Takayuki NISHIO Masahiro MORIKURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2014/09/01
Vol. E97-B  No. 9  pp. 1817-1825
Type of Manuscript:  Special Section PAPER (Special Section on Ambient Intelligence and Sensor Networks)
Category: 
Keyword: 
demand-side energy managementsmart gridsdifferential gameoptimal controlinformation availabilitydecentralized control
 Summary | Full Text:PDF(1.5MB)

Implementation and Feasibility Study of Co-channel Operation System of Microwave Power Transmissions to IEEE 802.11-Based Batteryless Sensor
Shota YAMASHITA Norikatsu IMOTO Takuya ICHIHARA Koji YAMAMOTO Takayuki NISHIO Masahiro MORIKURA Naoki SHINOHARA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2014/09/01
Vol. E97-B  No. 9  pp. 1843-1852
Type of Manuscript:  Special Section PAPER (Special Section on Ambient Intelligence and Sensor Networks)
Category: 
Keyword: 
microwave power transmissionIEEE 802.11g-based wireless LANco-channel operationbatterylesstime schedulingsleep mode
 Summary | Full Text:PDF(3.7MB)

Experimental Investigation of Co-channel and Adjacent Channel Operations of Microwave Power and IEEE 802.11g Data Transmissions
Norikatsu IMOTO Shota YAMASHITA Takuya ICHIHARA Koji YAMAMOTO Takayuki NISHIO Masahiro MORIKURA Naoki SHINOHARA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2014/09/01
Vol. E97-B  No. 9  pp. 1835-1842
Type of Manuscript:  Special Section PAPER (Special Section on Ambient Intelligence and Sensor Networks)
Category: 
Keyword: 
microwave power transmissionIEEE 802.11CSMA/CAWLANadjacent channel interference
 Summary | Full Text:PDF(3.3MB)

Virtual Continuous CWmin Control Scheme of WLAN
Yuki SANGENYA Fumihiro INOUE Masahiro MORIKURA Koji YAMAMOTO Fusao NUNO Takatoshi SUGIYAMA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2014/01/01
Vol. E97-A  No. 1  pp. 40-48
Type of Manuscript:  Special Section PAPER (Special Section on Wideband Systems)
Category: Foundations
Keyword: 
CSMA/CAIEEE 802.11 DCFCWmin controlfairnessperformance analysis model
 Summary | Full Text:PDF(1.4MB)

IEEE 802.11ah Based M2M Networks Employing Virtual Grouping and Power Saving Methods
Kohei OGAWA Masahiro MORIKURA Koji YAMAMOTO Tomoyuki SUGIHARA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/12/01
Vol. E96-B  No. 12  pp. 2976-2985
Type of Manuscript:  Special Section PAPER (Special Section on Network and System Technologies for Sustainable Society)
Category: 
Keyword: 
M2M networkswireless LANIEEE 802.11ahEDCApower savingCSMA/CA
 Summary | Full Text:PDF(2MB)

Fixed-Rate Resource Exchange for Multi-Operator Pico eNodeB
Tomohiko MIMURA Koji YAMAMOTO Masahiro MORIKURA Ayako IWATA Takashi TAMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/11/01
Vol. E96-B  No. 11  pp. 2913-2922
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
multi-operatorpico eNodeBresource allocationgame theorymechanism design
 Summary | Full Text:PDF(2MB)

A 250 Msps, 0.5 W eDRAM-Based Search Engine Dedicated Low Power FIB Application
Hisashi IWAMOTO Yuji YANO Yasuto KURODA Koji YAMAMOTO Kazunari INOUE Ikuo OKA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2013/08/01
Vol. E96-C  No. 8  pp. 1076-1082
Type of Manuscript:  PAPER
Category: Integrated Electronics
Keyword: 
routeraddress lookuppower consumptionsearch engineTCAMlow power
 Summary | Full Text:PDF(2.8MB)

Deterministic Packet Buffer System with Multi FIFO Queues for the Advanced QoS
Hisashi IWAMOTO Yuji YANO Yasuto KURODA Koji YAMAMOTO Shingo ATA Kazunari INOUE 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/07/01
Vol. E96-B  No. 7  pp. 1819-1825
Type of Manuscript:  PAPER
Category: Network System
Keyword: 
packet buffermulti FIFO queuesmemory controllerquality services
 Summary | Full Text:PDF(2.5MB)

Game-Theoretic Analysis of Multibandwidth Channel Selection by Coordinated APs in WLANs
Kohei HANADA Koji YAMAMOTO Masahiro MORIKURA Koichi ISHIHARA Riichi KUDO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/06/01
Vol. E96-B  No. 6  pp. 1277-1287
Type of Manuscript:  Special Section PAPER (Special Section on Heterogeneous Networks for Future Cellular Systems)
Category: 
Keyword: 
wireless LANmultibandwidthchannel selectionIEEE 802.11acoverlapping BSSgame theory
 Summary | Full Text:PDF(1.6MB)

Multi-Operator Mobile Relaying: Shared-Spectrum Allocation
Tomohiko MIMURA Koji YAMAMOTO Masahiro MORIKURA Ayako IWATA Akihiko NISHIO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/06/01
Vol. E96-B  No. 6  pp. 1377-1384
Type of Manuscript:  Special Section PAPER (Special Section on Heterogeneous Networks for Future Cellular Systems)
Category: 
Keyword: 
multi-operatormobile relayingschedulingbargaining game
 Summary | Full Text:PDF(2MB)

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:  INVITED PAPER (Special Section on Wideband Systems)
Category: 
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(701.6KB)

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(280.4KB)

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(780.5KB)

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:  INVITED PAPER (Special Section on Wireless Distributed Networks)
Category: 
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)

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(827.8KB)

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(924.8KB)

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(228.5KB)

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(529KB)

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(554.4KB)

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(681.7KB)

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(692.1KB)

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(491.6KB)

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(479.9KB)

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(428.3KB)

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(639.4KB)

Fault-Tolerant Graphs for Hypercubes and Tori*
Toshinori YAMADA Koji YAMAMOTO Shuichi UENO 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 1996/08/25
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(506.1KB)