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Performance of multiuser CDMA system with space-time block coding in MIMO Rayleigh fading channels

Science in China(Series F) 2009年第12期52卷 2296-2307页

作者： YU XiangBin DONG Tao BI GuangGuo College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China School of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

In this paper, by introducing orthogonal space-time coding scheme, the multiuser CDMA systems with different space time codes are given, and corresponding system performance is investigated over Rayleigh fading channel. A low-complexity multiuser receiver scheme is developed for space-time coded CDMA systems. The scheme can make full use of the complex orthogonality of space-time coding to simplify the high decoding complexity of the existing scheme. Compared to the existing scheme with exponential decoding complexity, it has linear decoding complexity. Based on the performance analysis and mathematical calculation, average bit error rate （BER） of the system is derived in detail, and tight closed-form approximation expressions of BER are attained. Simulation results on average BER are in agreement with the theory analysis. The results show that the proposed scheme can achieve almost the same performance as the existing scheme. Moreover, on the condition of same system throughput and concatenation of channel code, the given full-rate space-time coded CDMA system has lower BER than the full-diversity space-time coded CDMA systems.

关键词： space-time block coding code division multiple access （CDMA） full diversity full rate multiple input multiple output （MIMO）

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Error Control Coded space-time block coding for Frequency-Selective Fading Channels

Error Control Coded Space-Time Block Coding for Frequency-Se...

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1st International Workshop on Education Technology and Computer Science

作者： Zhang, Jieyin Zhang, Minxia Univ Leeds Dept Elect & Elect Engn Leeds LS2 9JT W Yorkshire England Qingdao Technol Univ Dept Comp Sci Qingdao Peoples R China

ISBN: (纸本)9780769535579

To achieve high data rate and spectral efficiency requirement, diversity techniques are designed to compensate fading channel impairments. Transmitter diversity scheme are preferred as they effectively increase data rates for all the receivers in their coverage area. Since transmitter diversity techniques such as beamformers at the transmitter require feedback from the receiver, space-time block coding (STBC) is considered to be a powerful transmitter diversity technique as this scheme does not require any feedback from the receiver. The STBC scheme introduced by Alamouti([1]) is suitable only for flat fading channels. Therefore a transmitter diversity scheme called time-Reversal space-time block coding (TR-STBC) for frequency-selective fading channels is studied. Finally, error coding techniques are applied to the system which enhances the Bit Error Rate (BER) performance of TR-STBC scheme.

关键词： space-time block coding STBC TR-STBC

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Joint Channel Estimation and Data Detection for STBC MIMO-OFDM Wireless Communication System

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JOURNAL OF CIRCUITS SYSTEMS AND COMPUTERS 2015年第4期24卷 1550059-1550059页

作者： Patil, Gajanan R. Kokate, Vishwanath K. Army Inst Technol Pune 411015 Maharashtra India Sinhgad Coll Engg Pune 411041 Maharashtra India

This paper presents a joint channel estimation and data detection technique for multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) system. Initial estimate of the channel is obtained using semi-blind channel estimation (SBCE). The whitening rotation (WR)-based orthogonal pilot maximum likelihood (OPML) method is used to obtain the channel estimate. The estimate is further enhanced by extracting information through the received data symbols. The performance of the proposed estimator is studied under various channel models. The simulation study shows that this approach gives better performance over training-based channel estimation (TBCE) and OPML SBCE methods but at the cost of higher computational complexity.

关键词： Multiple input multiple output orthogonal frequency division multiplexing semi-blind channel estimation space-time block coding

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Decision Feedback Detection for space-time block coding over time-Selective Fading Channels

Decision Feedback Detection for Space-Time Block Coding over...

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69th IEEE Vehicular Technology Conference

作者： Yu, Donghun SAIT Commun Lab Yongin 446712 Kyunggido South Korea

ISBN: (纸本)9781424425167

Decision feedback detectors for space-time block coding are proposed to combat time-selective fading. Although there are many conventional detectors, better performance is obtained if non-linear techniques are used. If we first detect the most reliable element of the transmitted vector and use it to improve the detection of the other elements of the transmitted vector, better performance can be achieved. In this paper, we propose zero forcing decision feedback detector and MMSE decision feedback detector for space-time block coding. It is shown by simulations that the proposed decision feedback detectors outperform the conventional detectors when the channel is time-selective fading.

关键词： Detectors time-selective fading channels Decision feedback detection MIMO systems space-time block coding

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Power optimization of Decode-and-Forward assisted ARQ relaying

Power optimization of Decode-and-Forward assisted ARQ relayi...

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International Conference on Microelectronics

作者： Ali Kamouch Abdelaali Chaoub Zouhair Guennoun Laboratory of Electronic and Communication Mohammed V-Agdal University Rabat Morocco Department of Telecommunication National Institute of Posts and Telecommunications Rabat Morocco

In this paper we investigate the performances of Decode-and-forward (DF) assisted by automatic repeat request (ARQ) relaying over Rayleigh fast fading channel. We derive a tight asymptotic approximation of the outage probability at high signal-to-noise ratio(SNR) regime. Furthermore we formulate an optimization problem aiming at achieving a target outage probability with an optimum allocation of the power budget depending on the relative position of the relay with regard to source and destination.

关键词： Decode and forward Automatic retransmission request maximum ratio combining Outage probability Power allocation space-time block coding

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Unified Analysis of Multiuser Scheduling for Downlink MIMO Systems with Imperfect CSI

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2014年第3期13卷 1344-1355页

作者： Yu, Xiangbin Dang, Xiaoyu Leung, Shu-Hung Liu, Yan Yin, Xin Nanjing Univ Aeronaut & Astronaut Dept Elect Engn Nanjing Jiangsu Peoples R China City Univ Hong Kong Dept Elect Engn Hong Kong Hong Kong Peoples R China City Univ Hong Kong State Key Lab Millimeter Wave Hong Kong Hong Kong Peoples R China City Univ Hong Kong Dept Elect Engn Hong Kong Hong Kong Peoples R China

In this paper, unified BER performance and outage probability analyses of downlink multiuser scheduling for multiple-input multiple-output (MUS-MIMO) transmission/combining (transceiving) systems with imperfect channel state information (CSI) caused by feedback over Rayleigh fading channels is presented. The unified analysis is applicable to MIMO transceiving systems whose received signal-to-noise ratio (SNR) is given as largest order statistic of chi-square distribution. The performance of MUS-MIMO employing selective transmission/selective combining (ST/SC), ST/maximum ratio combining (MRC) and space-time block codes (STBC) can be analyzed by this general framework. Accurate and approximate unified closed-form BER and outage probability expressions of the MUS-MIMO transceiving system with normalized SNR-based scheduling in heterogeneous networks are derived. Based on the approximate BER and outage probability expressions, diversity gains are analyzed at high SNR. The results indicate that the MUS-MIMO for using the three transceiving schemes can achieve full diversity order for perfect CSI, while the diversity gain is degraded differently for the three transceiving schemes under imperfect CSI. Computer simulation shows that the theoretical analysis is in good agreement with simulation results, and the approximate BER expressions are very close to the accurate ones but with lower computational complexity.

关键词： Multiuser MIMO bit error rate user scheduling space-time block coding antenna selection imperfect CSI

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Blind and semi-blind ML detection for space-time block-coded OFDM wireless systems

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EURASIP JOURNAL ON ADVANCES IN SIGNAL PROCESSING 2014年第1期2014卷 1-14页

作者： Zaib, Alam Al-Naffouri, Tareq Y. King Fahd Univ Petr & Minerals Dept Elect Engn Dhahran 31261 Saudi Arabia King Abdullah Univ Sci & Technol Dept Elect Engn Thuwal 239556900 Saudi Arabia

This paper investigates the joint maximum likelihood (ML) data detection and channel estimation problem for Alamouti space-time block-coded (STBC) orthogonal frequency-division multiplexing (OFDM) wireless systems. The joint ML estimation and data detection is generally considered a hard combinatorial optimization problem. We propose an efficient low-complexity algorithm based on branch-estimate-bound strategy that renders exact joint ML solution. However, the computational complexity of blind algorithm becomes critical at low signal-to-noise ratio (SNR) as the number of OFDM carriers and constellation size are increased especially in multiple-antenna systems. To overcome this problem, a semi-blind algorithm based on a new framework for reducing the complexity is proposed by relying on subcarrier reordering and decoding the carriers with different levels of confidence using a suitable reliability criterion. In addition, it is shown that by utilizing the inherent structure of Alamouti coding, the estimation performance improvement or the complexity reduction can be achieved. The proposed algorithms can reliably track the wireless Rayleigh fading channel without requiring any channel statistics. Simulation results presented against the perfect coherent detection demonstrate the effectiveness of blind and semi-blind algorithms over frequency-selective channels with different fading characteristics.

关键词： Blind ML detection OFDM space-time block coding

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Cross-layer in MIMO-OFDM System with Adaptive Modulation and coding:Design and Analysis

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Chinese Journal of Electronics 2014年第2期23卷 371-376页

作者： ZHAO Junhui GUAN Xin LI Xiuping ZENG Longji State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University National Mobile Communications Research Laboratory Southeast University Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences School of Electronic Engineering Beijing University of Posts and Telecommunications

The queuing performance of the cross-layer system with space-time block code(STBC) over Multiinput-multi-output(MIMO) channel is analyzed. The Adaptive modulation and coding(AMC) in physical layer and finite length of buffer in data-link layer are combined with this model. A simple cross-layer design and the queue state process are proposed based on finite state Markov channel model, which is to solve the service process. The proposed cross-layer design is also incorporated with STBC to further improve the system performance. Simulation results illustrate the dependence of system performance on various parameters, and quantify the performance gain due to cross-layer optimization. The adjustment of target packet loss rate of adaptive modulation coding in physical layer can maximize average throughput of the system,meanwhile a significant improvement of the system performance is brought.

关键词： Adaptive modulation and coding Crosslayer design Multi-input-multi-output space-time block coding

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On the performance of multi-hop wireless relay networks

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WIRELESS COMMUNICATIONS & MOBILE COMPUTING 2014年第1期14卷 145-160页

作者： Jaafar, Wael Ajib, Wessam Haccoun, David Ecole Polytech Dept Elect Engn Montreal PQ H3C 3A7 Canada Univ Quebec Dept Comp Sci Montreal PQ H3C 3P8 Canada

User cooperation has evolved as a popular coding technique in wireless relay networks (WRNs). Using the neighboring nodes as relays to establish a communication between a source and a destination achieves an increase of the diversity order. The relay nodes can be seen as a distributed multi-antenna system, which can be exploited for transmit diversity by using distributed space-time block coding (STBC). In this paper, we investigate the bit error rate (BER) of multi-hop WRNs employing distributed STBC at the relay nodes. We develop the general model of WRNs using distributed STBC, and we derive the pairwise error probability and an approximation of the BER. We examine the impact of several parameters, such as distributed STBC at the relays, the number of relays, the distances between the nodes, and the channel state information available at the receivers, on the BER performance of the multi-hop WRN. The obtained results provide guidelines about the expected error performance and the design of channel estimation for these networks. Copyright (c) 2011 John Wiley & Sons, Ltd.

关键词： relay networks space-time block coding channel state information multi-hop

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Alamouti-Type STBC for Atmospheric Optical Communication Using Coherent Detection

IEEE PHOTONICS JOURNAL

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IEEE PHOTONICS JOURNAL 2014年第1期6卷 1页

作者： Niu, Mingbo Cheng, Julian Holzman, Jonathan F. Queens Univ Dept Elect & Comp Engn Kingston ON K7L 3N6 Canada Univ British Columbia Sch Engn Kelowna BC V1V 1V7 Canada

Alamouti-type space-time block coding is studied for optical wireless communication systems using coherent detection over atmospheric turbulence channels. Atmospheric turbulence-induced fading and phase noise are known to impair the performance of coherent optical wireless systems. Two new Alamouti-type space-time coded architectures are proposed to overcome turbulence-induced fading and phase noise from transmitter lasers, receiver local oscillators, and turbulence channels. Their error rate performance is analyzed for a wide range of turbulence conditions. With developed analytical error rate expressions, the usefulness of the proposed Alamouti-type space-time block coding is demonstrated for coherent optical wireless communication systems. Numerical results confirm the performance improvements of the proposed systems over that of single-input-single-output systems.

关键词： Atmospheric turbulence coherent detection optical communication phaseshift keying symbol error rate space-time block coding

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