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2009 ISECS International Colloquium on Computing, Communication, Control, and Management

作者： Li Zhengquan 1,2 1 Information Engineering College, Yangzhou University,Yangzhou 225009,China 2 National Mobile Communications Research Laboratory,Southeast University,Nanjing 210096,China Shen Lianfeng 2 2 National Mobile Communications Research Laboratory,Southeast University,Nanjing 210096,China Wang Jingjing 1 1 Information Engineering College, Yangzhou University,Yangzhou 225009,China

A new kind of constellation rotation for quasi-orthogonal space time polarization block code in keyhole channel is introduced in this *** kind of space time block code of 4 and 8 transmit antennas are designed,the new codes with full diversity can transmitted through dual-polarized antennas and received through dual-polarized *** the new codes is compared with the traditional quasi-orthogonal space–time block code in keyhole channel. Simulation result show that the new code can increase bit error rate compared with the constellation rotation for quasi-orthogonal space–time polarization block code in keyhole channel,and can reduce bit error rate compared with he traditional quasi-orthogonal space–time block code in keyhole channel.

关键词： space-time block code keyhole channel bit error rate constellation rotation

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Adaptive Semi-blind Channel Estimation for ST-BC MIMO-CDMA Systems with Hybrid User Signature

Adaptive Semi-blind Channel Estimation for ST-BC MIMO-CDMA S...

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International Symposium on Intelligent Signal Processing and Communications Systems (ISPACS)

作者： Chern, Shiunn-Jang Huang, Wang-Chih Yang, Richard Hsin-Hsyong Tamkang Univ Dept Elect Engn New Taipei City Taiwan Natl Kaohsiung First Univ Sci & Technol Dept Comp & Commun Kaohsiung Taiwan

ISBN: (纸本)9781467363617;978146736360+0

we extend our previous work to present a new semi-blind transceiver for the direct-sequence code division multiple access (DS-CDMA) system that uses multiple transmit and receive antennas (MIMO) system, equipped with space-time block code (ST-BC). In the transmitter we design a new hybrid augmented user signature (AUS) that composes of the desired user signatures and the prefix/postfix zero-padding sequences with respect to individual transmit-antennas. The hybrid AUS is devised to resolve the phase ambiguity problem which occurs in all blind receivers. At the receiver we propose a Capon-like semi-blind two-branch filter bank receiver, based on the linearly constrained constant modulus (LCCM) criterion, followed by the AUS-assisted semi-blind channel estimation and power method for block symbol recovery. This enables us to partially alleviate the effects of inter-block interference (IBI) and the multiple access interference (MAI). In the ST-BC MIMO-CDMA receiver with two-branch filterbank, we build on the generalized sidelobe canceller (GSC) structure with the RLS for implementing the adaptive semi-blind LCCM receiver. Via intense simulations it reveals that our proposed new transceiver has robust performance against the user's acquisition inaccuracies comparing with current available algorithms and to resolve the phase ambiguity problem.

关键词： WCDMA Capon receiver space-time block code MIMO hybrid user signature zero-padding GSC-RLS algorthm

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New Minimum Decoding Complexity Quasi-Orthogonal space-time block code for 8 Transmit Antennas

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2008年第10期E91A卷 2990-2994页

作者： Chae, Changhyeon Choi, Daewon Jung, Taejin Chonnam Natl Univ Sch Elect & Comp Engn Kwangju South Korea

In this paper, a new full-rate space-time block code (STBC) possessing a quasi-orthogonal (QO) property is proposed for QAM and 8 transmit antennas. This code is designed by serially concatenating a real constellation-rotating precoder with the Alamouti scheme. The QO property enables ML decoding to be done with joint detection of only four real symbols like the conventional minimum decoding complexity QO-STBC (MDC-QO-STBC). However. the proposed code is guaranteed to achieve full spatial diversity for general QAM unlike the MDC-QO-STBC which is specifically presented for only 4-QAM. By computer simulation results, we show that the proposed code exhibits the identical and slightly degraded error performance with the MDC-QO-STBC for 4-QAM and the Sharma's QO-STBC for 4 and 16-QAM, respectively. Finally, we present a new modified scheme of the original code so that there is no any discontinuity of transmission at each transmit antenna, without any loss oferror performance.

关键词： multiple antennas space-time block code

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Exploiting Cross-Layer Packet Overhearing for Opportunistic Distributed STC in Wireless Relay Networks

Exploiting Cross-Layer Packet Overhearing for Opportunistic ...

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International Conference on Computing, Networking and Communications (ICNC)

作者： Argyriou, Antonios Univ Thessaly Dept Comp & Commun Engn Volos 38221 Greece

ISBN: (纸本)9781467300094

In this paper we propose a distributed Alamouti-based space-time code (STC) where opportunistic listening of packets from independent sources is exploited. Relays overhear broadcasted packets from multiple sources and acknowledge them dynamically. Acknowledgments are also overheard, allowing thus the relays to know the received packets at their neighbors. At each relay, the overheard data packets are multiplexed for generating in a distributed fashion the Alamouti STC that is broadcasted by the relays. Depending on the overheard packets the two relays may use dynamically the aforementioned multiplexed Alamouti STC scheme, or classic decode-and- forward (DF), or exploit transmit diversity with decode and joint forward (DJF). We perform extensive Monte Carlo simulations for testing the proposed protocol and the Alamouti-based STC under different channel conditions in the studied network topology.

关键词： Cooperative protocol Alamouti scheme space-time block code distributed space-time code (DSTC) opportunistic listening

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Alternating Multiuser Detection with Soft Interference Cancellation for Heterogeneous-Signaling MIMO CDMA Systems

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WIRELESS PERSONAL COMMUNICATIONS 2012年第4期67卷 811-828页

作者： Tu, Yung-Ping Lu, Hoang-Yang Fang, Wen-Hsien Natl Taiwan Ocean Univ Dept Elect Engn Keelung Taiwan Natl Taiwan Univ Sci & Technol Dept Elect Engn Taipei Taiwan

This paper presents an effective alternating multiuser detector for the uplink of heterogeneous-signaling multiple-input multiple-output code division multiple access systems over multipath fading channels, where the data are transmitted using either spatially multiplexing for high transmission rate or space-time block code for transmit diversity gains. The new MUD first separates users into two groups according to their transmission signaling schemes and then detects the transmitted symbols in each group alternately with the removal of iteratively refined soft information-assisted multiple access interference to enhance the interference cancellation capability. Moreover, for practical low-complexity implementations, the users in each group are further partitioned into smaller subgroups based on their effective channel correlations and then detected in parallel by a bank of minimum mean-squared error soft detectors to further reduce the computational load. Conducted simulations show that the proposed MUD can render superior performance compared with previous approaches, especially in highly loaded scenarios.

关键词： Multiple-input multiple-output systems CDMA Multiuser detection Spatially multiplexing space-time block code

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PERFORMANCE COMPARISON OF THE STBC-OFDM DEcodeRS IN A FAST FADING CHANNEL

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JOURNAL OF MARINE SCIENCE AND TECHNOLOGY-TAIWAN 2012年第5期20卷 534-540页

作者： Li, Chi-Min Li, Guo-Wei Liu, Han-Yi Natl Taiwan Ocean Univ Dept Commun Nav & Control Engn Keelung Taiwan

In a fast fading channel, the orthogonality of the two consecutive STBC-OFDM symbols will be destroyed and the received signals can not be perfectly separated. As a result, the bit error rate (BER) performance will be degraded seriously. In this paper, we analyze several co-channel interference (CCI) cancellation decoders for the STBC-OFDM in a fast fading channel including the Alamouti method, SIC method, ML method, DMLD method, and a proposed DZFD method. The proposed DZFD method has the advantage of reducing the computational complexity for the DMLD method. We also conduct the outdoor channel measurements to verify the CCI cancellation ability for different methods.

关键词： space-time block code OFDM fast fading channel

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Comparative Study of Open-Loop Transmit Diversity Schemes for DFT-Precoded OFDMA in Frequency-Selective Fading Channels

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IEICE TRANSACTIONS ON COMMUNICATIONS 2012年第12期E95B卷 3708-3718页

作者： Deng, Lianjun Kawamura, Teruo Taoka, Hidekazu Sawahashi, Mamoru Tokyo City Univ Dept Informat Network Engn Tokyo 1588557 Japan NTT DOCOMO INC Radio Access Network Dev Dept Yokosuka Kanagawa 2398536 Japan DOCOMO Commun Labs Europe GmbH Munich Germany

This paper presents comprehensive comparisons based on the block error rate (BLER) of open-loop (OL) transmit diversity schemes considering a cubic metric (CM) for single-carrier (SC)-Frequency Division Multiple Access (FDMA) using discrete Fourier transform (DFT)-precoded OFDMA in uplink frequency-selective fading channels. The OL transmit diversity schemes assumed in the paper are space-time block code (STBC), space-frequency block code (SFBC), single-carrier (SC) - SFBC, cyclic delay diversity (CDD), and frequency switched transmit diversity (FSTD) for two antennas and a combination of STBC, SFBC, SC-SFBC and selection transmit diversity including time switched transmit diversity (TSTD) or FSTD for four antennas. We derive the most appropriate OL transmit diversity scheme for SC-FDMA using a frequency domain equalizer (FDE) with QPSK and 16QAM modulations and with various channel coding rates employing turbo coding. We investigate the best OL transmit diversity scheme under various propagation channel conditions including the fading maximum Doppler frequency and root mean square (r.m.s.) delay spread, and the fading correlation between transmitter/receiver antennas.

关键词： transmit diversity space-time block code space-frequency block code single-carrier FDMA

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Variable-power discrete-rate adaptive modulation with orthogonal space-time block coding for Nakagami-m fading channels

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TRANSACTIONS ON EMERGING TELECOMMUNICATIONS TECHNOLOGIES 2012年第1期23卷 16-24页

作者： Yu, Xiangbin Leung, Shu-Hung Wong, Wai-Ki Nanjing Univ Aeronaut & Astronaut Dept Elect Engn Nanjing Jiangsu Peoples R China City Univ Hong Kong Dept Elect Engn Kowloon Hong Kong Peoples R China

The performance analysis of a space-time coded multiple-input and multiple-output system with variable-power adaptive modulation over Nakagami-m fading channels is presented. The optimum switching thresholds for attaining maximum spectrum efficiency (SE) subject to a target bit error rate (BER) and an average power constraint are derived. The existence and uniqueness of the Lagrange multiplier used in the constrained optimization are discussed. The probability density functions of instantaneous signal-to-noise ratio for both perfect and imperfect channel state information are derived, which lead to deriving closed-form SE and BER expressions. Simulation results show that the theoretical analysis and simulation are in good agreement. The variable-power adaptive modulation with space-time coding provides SE better than the constant power counterpart, and it has performance degradation in SE and BER for imperfect channel state information. Copyright (C) 2011 John Wiley & Sons, Ltd.

关键词： adaptive modulation variable power space-time block code Nakagami fading imperfect CSI MIMO

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Performance Analysis of space-time coded CDMA System Over Nakagami Fading Channels with Perfect and Imperfect CSI

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WIRELESS PERSONAL COMMUNICATIONS 2012年第3期62卷 633-653页

作者： Yu, Xiangbin Xu, Dazhuan Nanjing Univ Aeronaut & Astronaut Coll Informat Sci & Technol Nanjing 210016 Peoples R China City Univ Hong Kong Dept Elect Engn Hong Kong Hong Kong Peoples R China Nanjing Univ Aeronaut & Astronaut Informat & Commun Engn Postdoctoral Res Stn Nanjing 210016 Peoples R China

In this paper, the performance of multiuser CDMA systems with different space time code schemes is investigated over Nakagami fading channel. Low-complexity multiuser receiver schemes are developed for space-time coded CDMA systems with perfect and imperfect channel state information (CSI). The schemes can make full use of the complex orthogonality of space-time coding to obtain the linear decoding complexity, and thus simplify the exponential decoding complexity of the existing scheme greatly. Moreover, it can achieve almost the same performance as the existing scheme. Based on the bit error rate (BER) analysis of the systems, the theoretical calculation expressions of average BER are derived in detail for both perfect CSI and imperfect CSI, respectively. As a result, tight closed-form BER expressions are obtained for space-time coded CDMA with orthogonal spreading code, and approximate closed-form BER expressions are attained for space-time coded CDMA with quasi-orthogonal spreading code. Computer simulation for BER shows that the theoretical analysis and simulation are in good agreement. The results show that the space-time coded CDMA systems have BER performance degradation for imperfect CSI.

关键词： Multiuser receiver code division multiple access (CDMA) space-time block code Nakagami fading channel Imperfect channel state information

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Modulation Diversity for Spatial Modulation Using Complex Interleaved Orthogonal Design

Modulation Diversity for Spatial Modulation Using Complex In...

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IEEE Region 10 Conference (TENCON) - Sustainable Development through Humanitarian Technology

作者： Rajashekar, Rakshith Hari, K. V. S. Indian Inst Sci Dept Elect Commun Engn Bangalore 560012 Karnataka India

ISBN: (纸本)9781467348232;9781467348225

In this paper, we propose modulation diversity techniques for Spatial Modulation (SM) system using Complex Interleaved Orthogonal Design (CIOD). Specifically, we show that the standard SM scheme can achieve a transmit diversity order of two by using the CIOD meant for two transmit antenna system without incurring any additional system complexity or bandwidth requirement. Furthermore, we propose a low-complexity maximum likelihood detector for our CIOD based SM schemes by exploiting the structure of the CIOD. We show with our simulation results that the proposed schemes offer transmit diversity order of two and give a better symbol error rate performance than the conventional SM scheme.

关键词： Spatial modulation space-time block code complex interleaved orthogonal design diversity decoding complexity

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