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Data throughputs using, multiple-input multiple-output (MIMO), techniques in a noise-limited cellular environment

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2002年第2期1卷 226-235页

作者： Catreux, S Driessen, PF Greenstein, LJ Iospan Wireless San Jose CA 95131 USA Univ Victoria Victoria BC V8W 5C3 Canada AT&T Labs Res Middletown NJ 07748 USA

We present a general framework to quantify the data throughput capabilities of a wireless communication system when it combines: 1) multiple transmit signals;2) adaptive modulation for each signal;and 3) adaptive array processing at the receiver. We assume a noise-limited environment, corresponding to either an isolated cell or a multicell system whose out-of-cell interference is small compared with the thermal noise. We focus on the user data throughput, in bits per second/Hertz (bps/Hz), and its average over multipath fading, which we call the user spectral efficiency. First, an analysis method is developed to find the probability distribution and mean value of the spectral efficiency over the user positions and shadow fadings, both as. a function of user distance from its serving base station and averaged over the cell coverage area. We assume fading conditions and receiver processing that lend themselves to closed-form analysis. The resulting formulas are simple and straightforward to compute, and they provide a number of valuable insights. Next, we run Monte Carlo simulations, both to confirm the analysis and to treat cases less amenable to simple analysis. A key contribution of this paper is a simple formula for the mean spectral efficiency in terms of the propagation exponent, mean signal-to-noise ratio at the cell boundary, number of antennas, and type of coding. Under typical propagation conditions, the mean spectral efficiency using three transmit and three receive antennas ranges from 19.2 bps/Hz (uncoded) to 26.8 bps/Hz (ideally coded), highlighting the potential benefits of multiple transmissions combined with adaptive techniques. This is much higher than the spectral efficiencies for a link using a single transmitter and a threefold receive diversity under the same conditions, where the range is from 8.77 bps/Hz to 11.4 bps/Hz. Moreover, the latter results are not nearly as practical to achieve, as they call for large signal constellations that would b

关键词： adaptive modulation antenna arrays fading channels land mobile radio cellular systems multiple-input multiple-output

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On the construction of high-rate quasi-orthogonal STBC for MIMO QR demodulation

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2005年第7期E88D卷 1417-1429页

作者： Le, MT Pham, VS Mai, L Yoon, G Informat & Commun Univ Sch Engn Taejon 305714 South Korea

Orthogonal space-time block codes (STBCs) [1], [2] appear to be a very fascinating means of enhancing reception quality in quasistatic MIMO channels due to their full diversity, and especially their simple maximum-likelihood (ML) decoders. However, full-rate full-diversity orthogonal STBCs do not exist for more than two transmit antennas. Vertical layered space-time architecture (so-called the V-BLAST) [3] with a nulling- and cancelling-based detection algorithm, in contrast, has an ability of achieving high transmission rates at the cost of having very low diversity gain, an undesirable consequence caused by the interference nulling and cancelling processes. The uncoded V-BLAST system is able to reach its ML performance with the aid of the sphere decoder algorithm [4] at the expense of higher detection complexity. Undoubtedly, the tradeoff between transmission rates, diversity, and complexity is inherent in designing space-time codes. This paper investigates a method to increase the "nulling diversity gains" for a general high-rate space-time code and introduces a new design strategy for high-rate space-time codes detected based on interference nulling and cancelling processes, thanks to which high-rate quasi-orthogonal space-time codes for MIMO applications are proposed. We show that when n(T) transmit and n(R) = n(T) receive antennas are deployed, the first code offers a transmission rate of (n(T) - 1) with a minimum nulling diversity order of 3, whereas the second one offers a transmission rate of (n(T) - 2) with a minimum nulling diversity order of 5. Therefore, the proposed codes significantly outperform the V-BLAST as n(R) = n(T). Simulation results and discussions on the performance of the proposed codes are provided.

关键词： space-time coding multiple-input multiple-output maximum likelihood detection diversity wireless communication multipath channels

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Very-low-complexity maximum-likelihood decoders for four-transmit-antenna quasi-orthogonal space-time code

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IEICE TRANSACTIONS ON COMMUNICATIONS 2005年第9期E88B卷 3802-3805页

作者： Le, MT Pham, VS Mai, L Yoon, G Informat & Commun Univ CEL Lab Taejon 305714 South Korea

This letter proposes two very-low-complexity maximum-likelihood (ML) detection algorithms based on QR decomposition for the quasi-orthogonal space-time code (QSTBC) with four transmit antennas [3]-[5], called VLCMLDec1 and VLCMLDec2 decoders. The first decoder, VLCMLDec1, can be used to detect transmitted symbols being extracted from finite-size constellations such as phase-shift keying (PSK) or quadrature amplitude modulation (QAM). The second decoder, VLCMLDec2, is an enhanced version of the VLCMLDec1, developed mainly for QAM constellations. Simulation results show that both of the proposed decoders enable the QSTBC to achieve ML performance with significant reduction in computational load.

关键词： space-time coding multiple-input multiple-output maximum likelihood detection diversity wireless communication

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Characterization and modeling of the MIMO propagation channel: An overview

Characterization and modeling of the MIMO propagation channe...

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8th European Conference on Wireless Technology (ECWT 2005)

作者： El Zein, Ghais Cosquer, Ronan Guillet, Julien Farhat, Hanna Sagnard, Florence IETR UMR 6164 CNRS INSA F-35043 Rennes France

ISBN: (纸本)296005511X

This paper deals with several aspects relative to the multiple-input multiple-output (MIMO) propagation channel. Different approaches used to model the MIMO channel are first presented. Then, the different measurement techniques used in order to characterize the propagation channel are described. Measurement campaigns made in urban environments have been analyzed to obtain the relevant statistical parameters of the channel. These results make it possible to discuss the integration of MIMO techniques in practical wireless communication systems.

关键词： MIMO systems statistical analysis wireless channels MIMO propagation channel multiple-input multiple-output statistical parameters wireless communication systems

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Space-time spreading for MIMO CDMA-based systems over fast-fading channels

Space-time spreading for MIMO CDMA-based systems over fast-f...

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International Conference on Wireless Networks, Communications and Mobile Computing

作者： Hamouda, W Concordia Univ Dept Elect & Comp Engn Montreal PQ HEG 1M8 Canada

ISBN: (纸本)0780393058

In this paper, a transmit diversity scheme based on space-time spreading for code-division multiple-access (CDMA) systems in fast-fading channels is introduced. The proposed transmit diversity scheme employs orthogonal Walsh spreading codes to exploit the time diversity introduced by the channel, and hence achieves two-fold of the diversity order obtained using conventional space-time spreading schemes. A generalization of the proposed coding scheme to systems with different antenna configurations is also discussed. For slowly-fading channels, we show that the proposed transmit diversity scheme reduces to that of conventional transmit diversity schemes with no performance degradation. For nonorthogonal spreading codes, we propose a receiver structure that employs an interference cancellation scheme to compensate for signal interference. Our results show a large performance improvement when using such an interference cancellation scheme relative to the conventional matched filter receiver.

关键词： multiple-input multiple-output space-time block codes flat-fading channels fast-fading direct-sequence code-division multiple access

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The performance of STBC coded MIMO-OFDM system based on turbo product codes

The performance of STBC coded MIMO-OFDM system based on turb...

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International Conference on Wireless Communications, Networking and Mobile Computing

作者： He, YJ Zhu, GX Zhang, BJ Zhang, ZM Li, X Huazhong Univ Sci & Technol Dept Elect & Informat Engn Wuhan 430074 Peoples R China

ISBN: (纸本)078039335X

Space-Time Block Codes(STBCs) are designed to obtain the full diversity gain. However, STBCs are not designed to achieve an additional coding gain. Therefore, STBCs need to be concatenated with an outer code which provides a significant coding gain. Turbo Product Codes (TPCs) are a kind of high-efficient coding scheme with low latency decoding, which do not suffer from an error floor associated with turbo codes. This article considers the concatenation of TPCs with STBCs and sets up coded MIMO-OFDM syatem to improve the reliability of the wireless communication systems. Finally, the paper presents simulating environment of experiment testing.

关键词： turbo product codes multiple-input multiple-output space-time block codes OFDM IMT2000

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Soft parallel decoding of per-antenna-coded MIMO systems

Soft parallel decoding of per-antenna-coded MIMO systems

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IEEE International Conference on Communications (ICC 2005)

作者： Mielczarek, B Krzymien, W Univ Alberta TRLabs Edmonton AB T6G 2V4 Canada

ISBN: (纸本)0780389387

In this paper, we consider a soft parallel decoding approach using probabilistic data association (PDA) algorithm for per-antenna-coded (PAC) transmission on multiple-input multiple-output (MIMO) channels. The proposed algorithm allows for decoding of layered signals in a variety of contexts: downlink and uplink in multi-user systems, single user transmission for both real-time and data traffic, systems with fewer receive than transmit antennas and with or without channel state information at the transmitter. We investigate performance of the proposed algorithm in turbo-coded MIMO systems using 16, 64, 256-QAM and spectral efficiencies ranging from 2 to 6 bpcu/layer. We present frame error rates for selected scenarios with the corresponding lower bounds on channel outage probabilities. We also briefly discuss the convergence properties of the PDA algorithm with turbo encoded signals.

关键词： probabilistic data association per-antenna-coding multiple-input multiple-output multi-user diversity M-QAM

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Performance Results of Space-time Block Coding Over Nakagami-m Fading Channels

Performance Results of Space-time Block Coding Over Nakagami...

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2005年无线通信、网络和移动计算国际会议

作者： Xudong Wang Dianwu Yue Bin Lin Yu Gong National Key Laboratory of Antenna and Microwave Technology Xidian University Xi'an 710071 China College of Information Engineering Dalian Maritime University Dalian 116026 China

ISBN: (纸本)078039335X

We study the performance of space-time block coding in terms of different transmission matrices over Nakagami-m fading channels in multiple-input multiple-output (MIMO) environments. A closed-form expression for the exact symbol error rate (SER) of orthogonal space-time block coding (OSTBC) over independent identically distributed Nakagami-m fading channels can be derived by means of the equivalent single-input single-output (SISO) model. The exact SERs of OSTBC with M-PSK and M-QAM modulations are expressed in terms of the moment generating function (MGF) of instantaneous SNR as well as the higher transcendental functions. In this paper, we provide performance evaluation results of several codes of OSTBC with the closed-form expressions;also, Monte Carlo simulation results are given, which demonstrate the accuracy of closed-form solutions. In addition, some new observations on the performance results of different code matrices are made.

关键词： MIMO systems Monte Carlo methods Nakagami channels block codes channel coding error statistics method of moments space-time codes Monte Carlo simulation Nakagami-m fading channels moment generating function multiple-input multiple-output orthogonal space multiple input multiple output systems Monte Carlo technique Block codes space time block coding Nakagami channels Moment generating function space-time codes Channel coding METHOD OF MOMENTS Fading channels

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A Stochastic MIMO Channel Model and the Analysis of the Spatial Correlation Properties

A Stochastic MIMO Channel Model and the Analysis of the Spat...

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2005年无线通信、网络和移动计算国际会议

作者： Ji Li Er-Yang Zhang School of Electronic Science and Engineering National University of Defense Technology Changsha China

ISBN: (纸本)078039335X

A physically in tuitional stochastic multiple-input multiple-output (MIMO) channel model is presented in this paper. It is realized as simple linear superposition architecture and has involved diversified effect of the wireless propagation. Then,the spatial correlation properties of the MIMO channel are analyzed exhaustively based on this model and results shows that the spatial correlation depends on the statistical properties of the channel, the antenna pattern, the separation between the antennas and the geometric configurations of the arrays.

关键词： MIMO systems antenna arrays antenna radiation patterns correlation methods stochastic processes wireless channels antenna pattern linear superposition architecture multiple-input multiple-output spatial correlation properties statistical properties stoch

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Jointly minimum BER transmitter and receiver FIR MIMO filters for binary signal vectors

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2004年第4期52卷 1021-1036页

作者： Hjorungnes, A Diniz, PSR de Campos, MLR Univ Oslo Dept Informat N-0316 Oslo Norway Univ Fed Rio de Janeiro COPPE Signal Proc Lab BR-21945970 Rio De Janeiro Brazil

A theory is developed for jointly minimizing the bit error rate (BER) between the desired and decoded signals with respect to the coefficients of transmitter and receiver finite impulse response (FIR) multiple-input multiple-output (MIMO) filters. The original signal is assumed to be a vector time-series with equally likely memoryless Bernoulli vector components. The channel model constitutes of a known FIR MIMO transfer function and Gaussian additive noise independent of the original signal. The channel input signal is assumed to be power constrained. Based on the formulas obtained, an iterative numerical optimization algorithm is proposed. When compared with other design methods available in the literature, the proposed method yields better results due to the generality of the model considered and the joint optimization of the transmitter-receiver pair.

关键词： FIR MIMO filters MIMO system multiple-input multiple-output

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