Yukihiko OKUMURA


Throughput Improvement of Mobile Cooperative WLAN Systems with Identifying and Management of Starved APs/UEs for 5G
Akiyoshi INOKI Hirantha ABEYSEKERA Munehiro MATSUI Kenichi KAWAMURA Takeo ICHIKAWA Yasushi TAKATORI Masato MIZOGUCHI Akira KISHIDA Yoshifumi MORIHIRO Takahiro ASAI Yukihiko OKUMURA 
Publication:   
Publication Date: 2017/08/01
Vol. E100-B  No. 8  pp. 1366-1376
Type of Manuscript:  Special Section PAPER (Special Section on Radio Access Technologies for 5G Mobile Communications System)
Category: Terrestrial Wireless Communication/Broadcasting Technologies
Keyword: 
5Gwireless LANthroughput starvationCSMA/CA
 Summary | Full Text:PDF(2.8MB)

Field Experimental Evaluation on 5G Millimeter Wave Radio Access for Mobile Communications
Yuki INOUE Shohei YOSHIOKA Yoshihisa KISHIYAMA Satoshi SUYAMA Yukihiko OKUMURA James KEPLER Mark CUDAK 
Publication:   
Publication Date: 2017/08/01
Vol. E100-B  No. 8  pp. 1269-1276
Type of Manuscript:  Special Section PAPER (Special Section on Radio Access Technologies for 5G Mobile Communications System)
Category: Wireless Communication Technologies
Keyword: 
5Gmillimeter wavebeam trackingstreet canyonshopping mallfield experiment
 Summary | Full Text:PDF(9MB)

Experimental Trial of 5G Super Wideband Wireless Systems Using Massive MIMO Beamforming and Beam Tracking Control in 28GHz Band
Tatsunori OBARA Tatsuki OKUYAMA Yuki INOUE Yuuichi AOKI Satoshi SUYAMA Jaekon LEE Yukihiko OKUMURA 
Publication:   
Publication Date: 2017/08/01
Vol. E100-B  No. 8  pp. 1256-1268
Type of Manuscript:  Special Section PAPER (Special Section on Radio Access Technologies for 5G Mobile Communications System)
Category: Wireless Communication Technologies
Keyword: 
5Ghigher frequency bandsmassive MIMObeamformingspatial multiplexingbeam tracking
 Summary | Full Text:PDF(10.2MB)

Improving Accuracy of Ray-Tracing Prediction in Non Line-of-Sight (NLOS) Urban Street Cell Environment beyond 6GHz
Nobutaka OMAKI Tetsuro IMAI Koshiro KITAO Yukihiko OKUMURA 
Publication:   
Publication Date: 2017/04/01
Vol. E100-B  No. 4  pp. 566-574
Type of Manuscript:  PAPER
Category: Antennas and Propagation
Keyword: 
ray-tracing5G wireless network systemmicrocellular environmentSHFEHF
 Summary | Full Text:PDF(2.7MB)

Path Loss Model for Outdoor-to-Indoor Corridor Up to 40GHz Band in Microcell Environments
Minoru INOMATA Motoharu SASAKI Wataru YAMADA Takeshi ONIZAWA Masashi NAKATSUGAWA Nobutaka OMAKI Koshiro KITAO Tetsuro IMAI Yukihiko OKUMURA 
Publication:   
Publication Date: 2017/02/01
Vol. E100-B  No. 2  pp. 242-251
Type of Manuscript:  Special Section PAPER (Special Section on Antenna and Propagation Technologies Contributing to Realization of Next Generation Wireless Systems)
Category: 
Keyword: 
propagation5Goutdoor-to-indoor path loss modelmillimeter wavehigh frequency bandsmicrocell environments
 Summary | Full Text:PDF(2.7MB)

Cluster Power Variation Characteristics for 3GHz-Band MIMO Communication System in a Crowded Indoor Environment
Kentaro SAITO Tetsuro IMAI Koshiro KITAO Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2016/05/01
Vol. E99-B  No. 5  pp. 1131-1142
Type of Manuscript:  PAPER
Category: Antennas and Propagation
Keyword: 
MIMO channel modelcrowded environmenthuman body shadowingindoor environmentquasi-static environment
 Summary | Full Text:PDF(2.8MB)

Joint Processing of Analog Fixed Beamforming and CSI-Based Precoding for Super High Bit Rate Massive MIMO Transmission Using Higher Frequency Bands
Tatsunori OBARA Satoshi SUYAMA Jiyun SHEN Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2015/08/01
Vol. E98-B  No. 8  pp. 1474-1481
Type of Manuscript:  Special Section PAPER (Special Section on 5G Radio Access Networks―Part I: Radio Access Technologies and System Design)
Category: 
Keyword: 
5Ghigher frequency bandsMassive MIMOanalog fixed beamformingCSI-based precoding
 Summary | Full Text:PDF(1.6MB)

Experimental Study on Ray Based Spatio-Temporal Channel Characteristics in Indoor Environment
Koshiro KITAO Tetsuro IMAI Kentaro SAITO Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2015/05/01
Vol. E98-B  No. 5  pp. 798-805
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Radio Propagation)
Category: 
Keyword: 
indoor channel modelspatio - temporal channelvector channel sounder
 Summary | Full Text:PDF(2.3MB)

Model for Estimating Effects of Human Body Shadowing in High Frequency Bands
Ngochao TRAN Tetsuro IMAI Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2015/05/01
Vol. E98-B  No. 5  pp. 773-782
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Radio Propagation)
Category: 
Keyword: 
human body shadowinghigh frequency bandsKEUTD
 Summary | Full Text:PDF(2.6MB)

Dynamic Channel Modeling Using Particle Filtering for Wireless MIMO Systems in Urban Environment
Kentaro SAITO Koshiro KITAO Tetsuro IMAI Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/10/01
Vol. E96-B  No. 10  pp. 2372-2379
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Antennas and Propagation in Conjunction with Main Topics of ISAP2012)
Category: Radio Propagation
Keyword: 
MIMOchannel modeltime-variant channelcluster-based channel modelparticle filter
 Summary | Full Text:PDF(3MB)

Investigation of Inter-Cell Interference Coordination Applying Transmission Power Reduction in Heterogeneous Networks for LTE-Advanced Downlink
Akihito MORIMOTO Nobuhiko MIKI Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/06/01
Vol. E96-B  No. 6  pp. 1327-1337
Type of Manuscript:  Special Section PAPER (Special Section on Heterogeneous Networks for Future Cellular Systems)
Category: 
Keyword: 
LTE-Advancedheterogeneous networkinter-cell interference coordinationcell range expansiontransmission power reduction
 Summary | Full Text:PDF(2.3MB)

Performance Evaluation of Interference Rejection Combining Receiver in Heterogeneous Networks for LTE-Advanced Downlink
Yusuke OHWATARI Akihito MORIMOTO Nobuhiko MIKI Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/06/01
Vol. E96-B  No. 6  pp. 1265-1276
Type of Manuscript:  Special Section PAPER (Special Section on Heterogeneous Networks for Future Cellular Systems)
Category: 
Keyword: 
LTE-Advancedheterogeneous networkinterference rejection combininginter-cell interference
 Summary | Full Text:PDF(3.7MB)

Investigation on Transmission Power Control Suitable for Heterogeneous Network Employing Cell Range Expansion in LTE-Advanced Uplink
Akihito MORIMOTO Nobuhiko MIKI Hiroyuki ISHII Daisuke NISHIKAWA Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/04/01
Vol. E96-B  No. 4  pp. 1051-1060
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
LTE-advancedheterogeneous networktransmission power controlcell range expansion
 Summary | Full Text:PDF(3.2MB)

Link Performance Modeling of Interference Rejection Combining Receiver in System Level Evaluation for LTE-Advanced Downlink
Yousuke SANO Yusuke OHWATARI Nobuhiko MIKI Akihito MORIMOTO Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2012/12/01
Vol. E95-B  No. 12  pp. 3739-3751
Type of Manuscript:  Special Section PAPER (Special Section on Coding and Coding Theory-Based Signal Processing for Wireless Communications)
Category: 
Keyword: 
LTE-Advancedinterference rejection combininginter-cell interferencesystem level simulationlink performance modelingturbo equalizer
 Summary | Full Text:PDF(2.3MB)

Impact on Inter-Cell Interference of Reference Signal for Interference Rejection Combining Receiver in LTE-Advanced Downlink
Yousuke SANO Yusuke OHWATARI Nobuhiko MIKI Yuta SAGAE Yukihiko OKUMURA Yasutaka OGAWA Takeo OHGANE Toshihiko NISHIMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2012/12/01
Vol. E95-B  No. 12  pp. 3728-3738
Type of Manuscript:  Special Section PAPER (Special Section on Coding and Coding Theory-Based Signal Processing for Wireless Communications)
Category: 
Keyword: 
LTE-Advancedinterference rejection combininginter-cell interferencereference signalturbo equalizer
 Summary | Full Text:PDF(3MB)

Performance Investigation on Cell Selection Schemes Associated with Downlink Inter-Cell Interference Coordination in Heterogeneous Networks for LTE-Advanced
Yuya SAITO Jaturong SANGIAMWONG Nobuhiko MIKI Satoshi NAGATA Tetsushi ABE Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2011/12/01
Vol. E94-B  No. 12  pp. 3304-3311
Type of Manuscript:  Special Section PAPER (Special Section on Cooperative Communications for Cellular Networks)
Category: 
Keyword: 
LTE-advancedheterogeneous networkcell selectionreference signal received powerreference signal received quality
 Summary | Full Text:PDF(2.4MB)

Investigation on Data Signal Muting to Improve Channel Estimation Accuracy in Downlink Coordinated Multiple-Point Transmission in LTE-Advanced
Yusuke OHWATARI Nobuhiko MIKI Tetsushi ABE Satoshi NAGATA Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2011/12/01
Vol. E94-B  No. 12  pp. 3321-3334
Type of Manuscript:  Special Section PAPER (Special Section on Cooperative Communications for Cellular Networks)
Category: 
Keyword: 
coordinated multipoint transmission/receptiondata signal mutingLTE-Advanced
 Summary | Full Text:PDF(5.6MB)

1. 92 Mbps Data Transmission Experiments over a Coherent W-CDMA Radio Link
Koichi OKAWA Yukihiko OKUMURA Mamoru SAWAHASHI Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1998/07/25
Vol. E81-B  No. 7  pp. 1330-1336
Type of Manuscript:  Special Section PAPER (Special Issue on Third Generation Land Mobile Communication Systems)
Category: 
Keyword: 
wideband CDMAmobile radioorthogonal multicode transmission
 Summary | Full Text:PDF(648.5KB)

Variable-Rate Data Transmission with Blind Rate Detection for Coherent DS-CDMA Mobile Radio
Yukihiko OKUMURA Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1998/07/25
Vol. E81-B  No. 7  pp. 1365-1373
Type of Manuscript:  Special Section PAPER (Special Issue on Third Generation Land Mobile Communication Systems)
Category: 
Keyword: 
DS-CDMAvariable-rate transmissionblind rate detection
 Summary | Full Text:PDF(703.1KB)

Further Results on Field Experiments of Coherent Wideband DS-CDMA Mobile Radio
Tomohiro DOHI Yukihiko OKUMURA Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1998/06/25
Vol. E81-B  No. 6  pp. 1239-1247
Type of Manuscript:  PAPER
Category: Mobile Communication
Keyword: 
DS-CDMAmobile radioreverse linktransmit power controlantenna diversityRake combining
 Summary | Full Text:PDF(790.6KB)

Experiments on Coherent Multicode DS-CDMA
Tomohiro DOHI Yukihiko OKUMURA Akihiro HIGASHI Koji OHNO Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1996/09/25
Vol. E79-B  No. 9  pp. 1326-1332
Type of Manuscript:  Special Section PAPER (Special Issue on Personal Communications)
Category: CDMA and multiple access technologies
Keyword: 
DS-CDMApilot symbol-aided coherent RAKEinterference power measurement based power controlorthogonal multicode transmissiontest-bedfield test
 Summary | Full Text:PDF(614.4KB)

Coherent Multicode DS-CDMA Mobile Radio Access
Fumyuki ADACHI Koji OHNO Akihiro HIGASHI Tomohiro DOHI Yukihiko OKUMURA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1996/09/25
Vol. E79-B  No. 9  pp. 1316-1325
Type of Manuscript:  Special Section PAPER (Special Issue on Personal Communications)
Category: CDMA and multiple access technologies
Keyword: 
DS-CDMAmobile raido accesscellular system
 Summary | Full Text:PDF(909.2KB)