Koichi ISHIHARA


Wide-Range and Fast-Tracking Non-Data-Aided Frequency Offset Estimator for QAM Optical Coherent Receivers
Tadao NAKAGAWA Takayuki KOBAYASHI Koichi ISHIHARA Yutaka MIYAMOTO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2016/07/01
Vol. E99-B  No. 7  pp. 1416-1425
Type of Manuscript:  PAPER
Category: Fiber-Optic Transmission for Communications
Keyword: 
optical fiber communicationoptical receiversquadrature amplitude modulationdigital signal processingfrequency offset estimation
 Summary | Full Text:PDF(2MB)

Maximum Likelihood Demodulators and Their Evaluations on Amplify-and-Forward Cooperative OFDM-Based Wireless LAN Systems
Hayato FUKUZONO Yusuke ASAI Riichi KUDO Koichi ISHIHARA Masato MIZOGUCHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2014/11/01
Vol. E97-B  No. 11  pp. 2435-2448
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
cooperative communicationorthogonal frequency division multiplexing (OFDM)wireless local area network (LAN)amplify-and-forward (AF) modeGolden codeAlamouti codelog likelihood ratio
 Summary | Full Text:PDF(2.7MB)

Implementation and Evaluation of Real-Time Distributed Zero-Forcing Beamforming for Downlink Multi-User MIMO Systems
Tomoki MURAKAMI Koichi ISHIHARA Riichi KUDO Yusuke ASAI Takeo ICHIKAWA Masato MIZOGUCHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2013/10/01
Vol. E96-B  No. 10  pp. 2521-2529
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Antennas and Propagation in Conjunction with Main Topics of ISAP2012)
Category: Wireless Communication Technologies
Keyword: 
multiuser MIMOinter-cell interferencedistributed systemwireless LAN system
 Summary | Full Text:PDF(4.7MB)

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)

A Band-Divided Receiver Prototype for Wideband Optical Signals
Munehiro MATSUI Riichi KUDO Yasushi TAKATORI Tadao NAKAGAWA Koichi ISHIHARA Masato MIZOGUCHI Takayuki KOBAYASHI Yutaka MIYAMOTO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2011/07/01
Vol. E94-B  No. 7  pp. 1801-1808
Type of Manuscript:  Special Section PAPER (Joint Special Section on Opto-electronics and Communications for Future Optical Network)
Category: 
Keyword: 
coherent receiveranalog to digital converterOFDMreal-timeheterodyne receiver
 Summary | Full Text:PDF(1.4MB)

A Novel Dynamic Channel Access Scheme Using Overlap FFT Filter-Bank for Cognitive Radio
Motohiro TANABE Masahiro UMEHIRA Koichi ISHIHARA Yasushi TAKATORI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2009/12/01
Vol. E92-B  No. 12  pp. 3589-3596
Type of Manuscript:  Special Section PAPER (Special Section on Dynamic Spectrum Access)
Category: Spectrum Allocation
Keyword: 
dynamic spectrum accesschannel accessoverlap FFTfilter-bank
 Summary | Full Text:PDF(1.1MB)

Frequency-Domain Equalization for Coherent Optical Single-Carrier Transmission Systems
Koichi ISHIHARA Takayuki KOBAYASHI Riichi KUDO Yasushi TAKATORI Akihide SANO Yutaka MIYAMOTO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2009/12/01
Vol. E92-B  No. 12  pp. 3736-3743
Type of Manuscript:  PAPER
Category: Fiber-Optic Transmission for Communications
Keyword: 
frequency-domain equalization (FDE)coherent optical transmissionchromatic dispersion (CD)polarization mode dispersion (PMD)digital signal processing (DSP)
 Summary | Full Text:PDF(2.6MB)

Overlap Frequency-Domain Multiuser Detection for Asynchronous Uplink Multiuser MIMO-OFDM Systems
Koichi ISHIHARA Yasushi TAKATORI Kentaro NISHIMORI Kazuyasu OKADA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2009/05/01
Vol. E92-B  No. 5  pp. 1582-1588
Type of Manuscript:  Special Section PAPER (Special Section on Radio Access Techniques for 3G Evolution)
Category: 
Keyword: 
multiuser MIMO (MU-MIMO)multiuser detection (MUD)OFDMuplinktiming offsetinter-block interference (IBI)
 Summary | Full Text:PDF(1MB)

New Robust Beamforming Method for Frequency Offsets in Uplink Multiuser OFDM-MIMO
Yasushi TAKATORI Riichi KUDO Atsushi OHTA Koichi ISHIHARA Kentaro NISHIMORI Shuji KUBOTA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2007/09/01
Vol. E90-B  No. 9  pp. 2312-2320
Type of Manuscript:  Special Section PAPER (Special Section on 2006 International Symposium on Antennas and Propagation)
Category: Smart Antennas
Keyword: 
multiuser MIMOuplinkbeamformingfrequency offset
 Summary | Full Text:PDF(782.4KB)

Frequency-Domain Multi-Stage Soft Interference Cancellation for DS-CDMA Uplink Signal Transmission
Koichi ISHIHARA Kazuaki TAKEDA Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2007/05/01
Vol. E90-B  No. 5  pp. 1152-1161
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
DS-CDMAfrequency-domain equalization (FDE)MUI cancellationmulti-user detection (MUD)
 Summary | Full Text:PDF(1.1MB)

Iterative Channel Estimation for Frequency-Domain Equalization of DSSS Signals
Koichi ISHIHARA Kazuaki TAKEDA Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2007/05/01
Vol. E90-B  No. 5  pp. 1171-1180
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
DSSSfrequency-domain equalization (FDE)channel estimation
 Summary | Full Text:PDF(1.9MB)

Frequency-Domain ICI Cancellation with MMSE Equalization for DS-CDMA Downlink
Kazuaki TAKEDA Koichi ISHIHARA Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2006/12/01
Vol. E89-B  No. 12  pp. 3335-3343
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
DS-CDMAfrequency-domain equalizationMMSEICI cancellation
 Summary | Full Text:PDF(988.3KB)

Iterative Frequency-Domain Soft Interference Cancellation for Multicode DS- and MC-CDMA Transmissions and Performance Comparison
Koichi ISHIHARA Kazuaki TAKEDA Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2006/12/01
Vol. E89-B  No. 12  pp. 3344-3355
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
DS-CDMAMC-CDMAfrequency-domain equalization (FDE)multicodeinterference cancelation
 Summary | Full Text:PDF(1.3MB)

Pilot-Assisted Decision Feedback Channel Estimation for STTD in OFDM Mobile Radio
Koichi ISHIHARA Kazuaki TAKEDA Fumiyuki ADACHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2005/02/01
Vol. E88-B  No. 2  pp. 561-567
Type of Manuscript:  Special Section PAPER (Special Section on Multi-carrier Signal Processing Techniques for Next Generation Mobile Communications--Part2)
Category: 
Keyword: 
pilotdecision feedbackchannel estimationOFDMSTTD
 Summary | Full Text:PDF(1.3MB)