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TRAITEMENT DU SIGNAL 2010年第2期27卷 147-160页

作者： Boutros, Joseph J. Randriambololona, Hugues Texas A&M Univ Qatar Doha 23874 Qatar Telecom ParisTech CNRS LTCI UMR 5141 F-75013 Paris France

We study linear unitary precoding for multiple antenna transmissions. Our aim is to find a new precoder satisfying both the genie conditions and the non-vanishing determinant criterion. Such a precoder will be optimized for both maximum likelihood and iterative probabilistic decoding. By combining the rank criterion and the genie conditions, we propose a new family of space-time codes over ℤ[i] defined by Pythagorean triples. In this family, the space-time code associated with the triple (3,4,5) - or with the quaternion algebra - is optimal. We will refer to it as Aladdin-Pythagoras, or more simply, Aladdin's Code. © 2010 Lavoisier, Paris.

关键词： Genie conditions Iterative probabilistic decoding Quaternion algebra Rank criterion space-time coding

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Differential space-time block code modulation for DS-CDMA systems

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EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2002年第3期2002卷 289-296页

作者： Liu, JH Li, J Larsson, EG Univ Florida Dept Elect & Comp Engn Gainesville FL 32611 USA

A differential space-time block code (DSTBC) modulation scheme is used to improve the performance of DS-CDMA systems in fast time-dispersive fading channels. The resulting scheme is referred to as the differential space-time block code modulation for DS-CDMA (DSTBC-CDMA) systems. The new modulation and demodulation schemes are especially studied for the down-link transmission of DS-CDMA systems. We present three demodulation schemes, referred to as the differential space-time block code Rake (D-Rake) receiver, differential space-time block code deterministic (D-Det) receiver, and differential space-time block code deterministic de-prefix (D-Det-DP) receiver, respectively. The D-Det receiver exploits the known information of the spreading sequences and their delayed paths deterministically besides the Rake type combination;consequently, it can outperform the D-Rake receiver, which employs the Rake type combination only. The D-Det-DP receiver avoids the effect of intersymbol interference and hence can offer better performance than the D-Det receiver.

关键词： wireless communications space-time coding smart antennas spread spectrum DS-CDMA Rake receiver

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Adaptive MIMO OFDM receivers: Implementation impairments and complexity issues *

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IFAC Proceedings Volumes 2004年第12期37卷 37-49页

作者： Alireza Tarighat Waleed M. Younis Ali H. Sayed Department of Electrical Engineering University of California Los Angeles CA 90095

MIMO OFDM communications is a promising choice for future high data rate wireless systems. However, the commercial deployment of MIMO OFDM systems faces some challenges, including those arising from front-end analog implementation impairments and complex receiver structures. The impairments are caused by the analog processing of the received radio frequency (RF) signal and they cannot be e±ciently nor entirely eliminated in the analog domain. This paper illustrates the e®ect of In-phase and Quadrature-phase (IQ) imbalances on system performance. Receiver algorithms are described that compensate for IQ imbalances. The structure of space-time block codes, along with the assumed structure of the distortion models, are exploited to design reduced-complexity adaptive receivers that are robust to IQ imbalances.

关键词： Orthogonal frequency division multiplexing (OFDM) multi-input-multi-output (MIMO) systems in-phase and quadrature-phase (IQ) imbalances space-time coding Alamouti scheme equalization adaptive receiver

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Cross-Layer Design for space-time coded MIMO Systems over Rice Fading Channel

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Physics Procedia 2012年 33卷 1176-1183页

作者： Xiangbin Yu Tingting Zhou Xiaoshuai Liu Xin Yin College of Information Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing China National Mobile Communication Research Laboratory Southeast UniversityNanjing China

A cross-layer design (CLD) scheme for space-time coded MIMO systems over Rice fading channel is presented by combining adaptive modulation and automatic repeat request, and the corresponding system performance is investigated well. The fading gain switching thresholds subject to a target packet error rate (PER) and fixed power constraint are derived. According to these results, and using the generalized Marcum Q-function, the calculation formulae of the average spectrum efficiency (SE) and PER of the system with CLD are derived. As a result, closed-form expressions for average SE and PER are obtained. These expressions include some existing expressions in Rayleigh channel as special cases. With these expressions, the system performance in Rice fading channel is evaluated effectively. Numerical results verify the validity of the theoretical analysis. The results show that the system performance in Rice channel is effectively improved as Rice factor increases, and outperforms that in Rayleigh channel.

关键词： Cross-layer design space-time coding Rice fading spectrum efficiency MIMO

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PERFORMANCE OF CLOSED LOOP TRANSMIT DIVERSITY IN A RAYLEIGH FADING CHANNEL

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Journal of Electronics(China) 2006年第1期23卷 29-34页

作者： Yang Xin You Xiaohu National Mobile Comm. Research Lab Dept of Radio Eng. Southeast Univ. Nanjing 210096 China

In this paper, the closed loop transmit diversity technology for the Wideband Code Division Multiple Access(WCDMA) systems is investigated in a multipath Rayleigh fading channel. The RAKE receiver model and the weighing vector algorithm are presented. The performance is theoretically analyzed in terms of the average maximal Signal-to-Noise Ratio(SNR) gain available over the space-time block coding based Transmit Diversity(STTD) technology. Theoretic analysis and simulation results show that the closed loop transmit diversity can provide a 3dB performance gain over the open loop scheme in a single path fading channel, while the performance gain decreases dramatically with the increasing inherent multipath diversity of the wireless channel.

关键词： Wideband Code Division Multiple Access(WCDMA) Transmit diversity Closed loop Openloop space-time coding

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Comments on "Semi-Blind Channel Estimation and Equalization for MIMO space-time Coded OFDM"

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS 2008年第11期55卷 3513-3513页

作者： Yu, Jung-Lang Lin, Yin-Cheng Fu Jen Catholic Univ Dept Elect Engn Taipei 242 Taiwan

A semiblind channel estimation scheme of the multiple-input-multiple-output space-time coded orthogonal frequency-division multiplexing system was proposed in the aforementioned paper for either real or complex with s... 详细信息

关键词： Channel-estimation multiple-input multiple-output (MIMO) space-time coding zero-padded (ZP) orthogonal frequency-division multiplexing (OFDM)

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Multiple Antenna Techniques in WiMAX Systems

ELEKTROTEHNISKI VESTNIK-ELECTROCHEMICAL REVIEW

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ELEKTROTEHNISKI VESTNIK-ELECTROCHEMICAL REVIEW 2008年第1-2期75卷 24-30页

作者： Celcer, T. Plevel, S. Javornik, T. Fortuna, C. Kandus, G. Jozef Stefan Inst Ljubljana Slovenia Jozef Stefan Inst Dept Commun Syst Ljubljana Slovenia Telsima Doo Trzin Slovenia

Multiple antenna systems can offer significant improvements in system performance due to their ability to exploit multipath signal propagation and take advantage of its random nature in order to achieve diversity or spatial multiplexing gain. As such, they are very suitable for implementation in WiMAX (Worldwide Interoperability for Microwave Access) systems to improve its performance in harsh urban and indoor environments. WiMAX physical layer is based on Orthogonal Frequency Division Multiplexing (OFDM), which is very robust to multipath propagation and enables straightforward usage of MIMO techniques. In this paper multiple antenna techniques and their use in Fixed and Mobile WiMAX systems are discussed. We present test results, collected with field measurements during a Fixed WiMAX system deployment, and describe results obtained by applying a channel simulator whose parameters are tuned according to field measurement data. A performance comparison between STC (space-time coding) and non-STC operation mode is analyzed for different coding and modulation schemes specified in the standard.

关键词： multiple antennas WiMAX space-time coding spatial multiplexing OFDM

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Performance Comparison of Sub-optimal Algorithms Based on MIMO-OFDM Systems

Performance Comparison of Sub-optimal Algorithms Based on MI...

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2008 11th IEEE International Conference on Communication Technology(ICCT2008)

作者： Wu Nian Wang Zhongpeng Zhejiang University of Science and Technology Hangzhou,China Zhang Shaozhong Faculty of Electronic and Information Engineering Zhejiang Wanli University Ningbo,China

Multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) is the key technique for generation communications *** this paper,several detection algorithms based on MIMO-OFDM systems are briefly introduced,and their performances are evaluated by computer *** simulation results indicate that performance of these algorithms for MIMO-OFDM system is similar to the performance for flat MIMO *** conclude that the socalled ZF-PIC algorithm is very attractive compared to conventional ZF-VBLAST in performance.

关键词： MIMO space-time coding frequency channel interference cancellation V-BLAST

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Spatio-Temporal Adaptive Array for Asynchronous Multiuser MIMO-STBC Transmission

Spatio-Temporal Adaptive Array for Asynchronous Multiuser MI...

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3rd International Symposium on Communications, Control, and Signal Processing (ISCCSP 2008), vol.1

作者： Nordin Bin Ramli Tetsuki Taniguchi Yoshio Karasawa Advanced Wireless Communication research Center (AWCC) University Of Electro-Communications Chofu Tokyo Japan

In this paper, we present a modified spatiotemporal adaptive array for multiuser space-time block codes (Modified STBC-TDLAA) transmission in frequency selective fading channel with the presence of co-channel interferences (CCIs). This method based on the transversal filter adaptive array perform the joint interference suppression and equalization. The presented Modified STBC-TDLAA can maximize the transmission efficiency by incorporating the receive signal component for both non-conjugated and the complex conjugated version of desired signal, which is dispersed in the received signal. Furthermore, Modified STBC-TDLAA overcomes the timing synchronization errors by realigning the asynchronous multiuser signal to undergo the synchronous joint interference suppression and equalization. Simulation results show that both our proposed scheme has a better performance than conventional STBC-TDLAA, in frequency selective fading channel.

关键词： space-time coding MIMO Tapped delay line adaptive array Frequency selective fading channel

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Multiple-Symbol Differential Detection for Cooperative System

Multiple-Symbol Differential Detection for Cooperative Syste...

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IEEE International Conference on Electronics, Communications and Control (ICECC)

作者： Chen, Jie Jin, Xiaoping Ying, Yingguo China Jiliang Univ Dept Informat Engn Hangzhou Zhejiang Peoples R China

ISBN: (纸本)9781457703218

Distributed space-time coding is a cooperative transmission scheme proposed for wireless relay networks. With this scheme, the performance of wireless communication can be greatly improved and the transmit rate can be perfectly accelerated. In this paper, using the maximum likelihood principle, we propose a multiple-symbol differential detection (MSDD) scheme, which reduces the 3dB gap between single-symbol differential detection and multiple-symbol detection. In MSDD for cooperative system over Rayleigh fading channels without channel state information, blocks of N received symbols are jointly processed to decide on N-1 data symbols. The simulation results show that our proposed MSDD is 1.5 dB better than single-symbol detection, at high SNR.

关键词： Multiple-Symbol detection (MSDD) space-time coding Cooperative System

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