Chang-Jun AHN

Multi Modulus Signal Adaptation for Semi-Blind Uplink Interference Suppression on Multicell Massive MIMO Systems
Kazuki MARUTA Chang-Jun AHN 
Publication:   
Publication Date: 2021/02/01
Vol. E104-B  No. 2  pp. 158-168
Type of Manuscript:  PAPER
Category: Antennas and Propagation
Keyword: 
massive MIMO, multicell, pilot contamination, multi modulus algorithm, channel estimation, decision feedback, beamspace, minimum mean square error, 
 Summary | Full Text:PDF(2.3MB)
Data-Aided SMI Algorithm Using Common Correlation Matrix for Adaptive Array Interference Suppression
Kosuke SHIMA Kazuki MARUTA Chang-Jun AHN 
Publication:   
Publication Date: 2021/02/01
Vol. E104-A  No. 2  pp. 404-411
Type of Manuscript:  Special Section PAPER (Special Section on Signal Design and Its Applications in Communications)
Category: Digital Signal Processing
Keyword: 
adaptive array, channel estimation, sample matrix invesion, decision feedback, 
 Summary | Full Text:PDF(1.5MB)
Improving Semi-Blind Uplink Interference Suppression on Multicell Massive MIMO Systems: A Beamspace Approach
Kazuki MARUTA Chang-Jun AHN 
Publication:   
Publication Date: 2019/08/01
Vol. E102-B  No. 8  pp. 1503-1511
Type of Manuscript:  Special Section PAPER (Special Section on Technology Trials and Proof-of-Concept Activities for 5G and Beyond)
Category: 
Keyword: 
massive MIMO, multicell, pilot contamination, adaptive array, constant modulus algorithm, channel estimation, decision feedback, beamspace, 
 Summary | Full Text:PDF(1.4MB)
Achievement Accurate CSI for AF Relay MIMO/OFDM Based on Complex HTRCI Pilot Signal with Enhanced MMSE Equalization
Yuta IDA Chang-Jun AHN Takahiro MATSUMOTO Shinya MATSUFUJI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2015/11/01
Vol. E98-A  No. 11  pp. 2254-2262
Type of Manuscript:  Special Section PAPER (Special Section on Smart Multimedia & Communication Systems)
Category: 
Keyword: 
AF relay transmissions, MIMO, OFDM, complex HTRCI pilot signal, enhanced MMSE equalization, 
 Summary | Full Text:PDF(1.8MB)
Removing Deep Faded Subcarrier Channel for Cooperative Multiuser Diversity OFDMA Based on Low Granularity Block
Yuta IDA Chang-Jun AHN Takahiro MATSUMOTO Shinya MATSUFUJI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2014/12/01
Vol. E97-A  No. 12  pp. 2586-2594
Type of Manuscript:  Special Section PAPER (Special Section on Signal Design and Its Applications in Communications)
Category: Communication Theory and Signals
Keyword: 
multiuser diversity OFDMA, low granularity block, cooperative communications, deep faded subcarrier channel, 
 Summary | Full Text:PDF(2.3MB)
Single Symbol Decodable QO-STBC with Full Diversity
Naotoshi YODA Chang-Jun AHN Ken-ya HASHIMOTO 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2014/01/01
Vol. E97-A  No. 1  pp. 2-6
Type of Manuscript:  Special Section PAPER (Special Section on Wideband Systems)
Category: Foundations
Keyword: 
QO-STBC, symbol modification, power imbalance, transmission diversity, 
 Summary | Full Text:PDF(814.8KB)
Heterogeneous Constellation Based QOSTBC for Improving Detection Property of QRD-MLD
Chang-Jun AHN Ken-ya HASHIMOTO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2012/08/01
Vol. E95-B  No. 8  pp. 2674-2677
Type of Manuscript:  LETTER
Category: Wireless Communication Technologies
Keyword: 
OSTBC, QOSTBC, MIMO, QRD-MLD, heterogeneous constellation, 
 Summary | Full Text:PDF(281.5KB)
Performance Enhancement of MQRD-PCM/MIMO-OFDM Using Channel Ranking Based Joint Symbols Detection
Chang-Jun AHN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2009/08/01
Vol. E92-A  No. 8  pp. 1913-1919
Type of Manuscript:  Special Section PAPER (Special Section on Signal Processing)
Category: Communications
Keyword: 
OFDM, MIMO, MQRD-PCM, channel ranking, inter-antenna interference (IAI), 
 Summary | Full Text:PDF(343.7KB)
Link Correlation Based Transmit Sector Antenna Selection for Alamouti Coded OFDM
Chang-Jun AHN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2009/03/01
Vol. E92-A  No. 3  pp. 816-823
Type of Manuscript:  Special Section PAPER (Special Section on Latest Advances in Fundamental Theories of Signal Processing)
Category: 
Keyword: 
MIMO, FBI, OFDM, antenna selection, sector antenna, 
 Summary | Full Text:PDF(743.5KB)
Throughput Improvement with Discrete Pilot Signal Assignment and Iterative Channel Identification for MQRD-PCM/OFDM
Chang-Jun AHN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2008/08/01
Vol. E91-A  No. 8  pp. 2000-2007
Type of Manuscript:  Special Section PAPER (Special Section on Signal Processing)
Category: 
Keyword: 
MIMO, OFDM, QR decomposition, MQRD-PCM, 
 Summary | Full Text:PDF(557.9KB)
Accurate Channel Identification with Time-Frequency Interferometry for OFDM
Chang-Jun AHN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2007/11/01
Vol. E90-A  No. 11  pp. 2641-2645
Type of Manuscript:  LETTER
Category: Communication Theory and Signals
Keyword: 
OFDM, time-frequency interferometry, CSI, 
 Summary | Full Text:PDF(254.2KB)
Subcarrier Block Power Control for Adaptive Downlink OFDM with Frequency Spreading and Equalization
Nam-Su KIM Sungho CHO Chang-Jun AHN 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2006/07/01
Vol. E89-B  No. 7  pp. 2102-2105
Type of Manuscript:  LETTER
Category: Wireless Communication Technologies
Keyword: 
subcarrier block power control, frequency symbol spreading, MMSEC, 
 Summary | Full Text:PDF(345.8KB)
Superimposed Frequency Symbol Based Adaptive Downlink OFDM with Frequency Spreading and Equalization
Chang-Jun AHN Hiroshi HARADA Yukiyoshi KAMIO 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2006/02/01
Vol. E89-B  No. 2  pp. 500-508
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
AMS/OFDM, frequency symbol spreading, frequency equalization, MMSEC, ORC, 
 Summary | Full Text:PDF(660KB)
Stochastic Method of Determining Substream Modulation Levels for MIMO Eigenbeam Space Division Multiplexing
Satoshi TAKAHASHI Chang-Jun AHN Hiroshi HARADA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2006/01/01
Vol. E89-B  No. 1  pp. 142-149
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
mobile radio propagation, adaptive modulation, multipath environments, ray tracing, MIMO, E-SDM, 
 Summary | Full Text:PDF(464.2KB)
Effect of Delay Spread Enhancement in MIMO Eigenbeam Space Division Multiplexing Transmission
Satoshi TAKAHASHI Chang-Jun AHN Hiroshi HARADA Yukiyoshi KAMIO 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2005/07/01
Vol. E88-A  No. 7  pp. 1931-1935
Type of Manuscript:  Special Section LETTER (Special Section on Multi-dimensional Mobile Information Networks)
Category: 
Keyword: 
radio propagation, delay spread, MIMO, E-SDM, 
 Summary | Full Text:PDF(392.6KB)
Adaptive Subcarrier Block Modulation with Differentially Modulated Pilot Symbol Assistance for Downlink OFDM Using Uplink Delay Spread
Chang-Jun AHN Satoshi TAKAHASHI Hiroshi HARADA Yukiyoshi KAMIO Iwao SASASE 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2005/07/01
Vol. E88-A  No. 7  pp. 1889-1896
Type of Manuscript:  Special Section PAPER (Special Section on Multi-dimensional Mobile Information Networks)
Category: Wireless Communication Technology
Keyword: 
DMPSA-ASMS/OFDM, MLI, coherence bandwidth, RMS delay spread, 
 Summary | Full Text:PDF(592.2KB)
Differential Modulated Pilot Symbol Assisted Adaptive OFDM for Reducing the MLI with Predicted FBI
Chang-Jun AHN Satoshi TAKAHASHI Hiroshi HARADA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2005/02/01
Vol. E88-B  No. 2  pp. 436-442
Type of Manuscript:  Special Section PAPER (Special Section on Multi-carrier Signal Processing Techniques for Next Generation Mobile Communications--Part2)
Category: 
Keyword: 
AMS/OFDM, MLI, FBI, 
 Summary | Full Text:PDF(520.1KB)
Reverse Link Performance Improvement for Wideband OFDM Using Alamouti Coded Heterogeneous Polarization Antennas
Chang-Jun AHN Yukiyoshi KAMIO Satoshi TAKAHASHI Hiroshi HARADA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2004/11/01
Vol. E87-B  No. 11  pp. 3281-3288
Type of Manuscript:  PAPER
Category: Wireless Communication Technologies
Keyword: 
OFDM, STBC, polarization, XPD, 
 Summary | Full Text:PDF(602.8KB)
Iterative Decoding with LDPC Based Unitary Matrix Modulated OFDM with Splitting the Diagonal Components over the Coherence Bandwidth
Chang-Jun AHN 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2004/08/01
Vol. E87-B  No. 8  pp. 2411-2414
Type of Manuscript:  LETTER
Category: Wireless Communication Technology
Keyword: 
LDPC, OFDM, coherence bandwidth, unitary matrix, 
 Summary | Full Text:PDF(277.4KB)
Multiple Pre-Rake Filtering Based on the Predicted Channel Impulse Response in the Transmitter and a Rake Combiner in the Receiver for TDD/DS-CDMA Mobile Communication Systems
Chang-Jun AHN Iwao SASASE 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2002/10/01
Vol. E85-B  No. 10  pp. 2282-2291
Type of Manuscript:  PAPER
Category: Wireless Communication Technology
Keyword: 
CDMA, Rake receiver, pre-Rake system, time division duplex (TDD), 
 Summary | Full Text:PDF(771.4KB)
Code Orthogonalizing Filter Based Adaptive Array Antenna Using Common Correlation Matrix of Time Domain Signals for Multicarrier DS/CDMA Systems
Chang-Jun AHN Iwao SASASE 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2002/07/01
Vol. E85-A  No. 7  pp. 1604-1611
Type of Manuscript:  Special Section PAPER (Special Section on Multi-dimensional Mobile Information Networks)
Category: 
Keyword: 
MC-DS/CDMA, code orthogonalizing filter (COF), sample matrix inversion (SMI), adaptive array antenna, common correlation matrix, 
 Summary | Full Text:PDF(667.6KB)