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Numerical Performance Evaluation for Alamouti space time Coded OFDM under Receiver Impairments

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2009年第3期8卷 1446-1455页

作者： Krondorf, Marco Fettweis, Gerhard Tech Univ Dresden Vodafone Chair Mobile Communicat Syst D-01069 Dresden Germany

We present a methodology for the analysis of the capacity and symbol/bit error rate performance of Alamouti space time coded OFDM links that jointly captures the aggregate effects of real life receiver imperfections and mobile channel effects. Specifically, we investigate carrier frequency offset, channel estimation error, outdated channel state information due to time selective channel properties and flat receiver I/Q imbalance. Hence, we provide a numerical tool for realistic Alamouti space time coded (STC) OFDM performance evaluation. The main contribution of this work is the derivation of the probability density function of the received frequency domain signal with respect to the mentioned impairments. The density function is then used for numerical calculations of both the symbol and bit error rates, as well as the capacity for Alamouti STC OFDM links. Finally, we illustrate which of the mentioned impairments has the most severe impact on the overall STC OFDM system performance. The abstract goes here.

关键词： OFDM space time coding RF impairments

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Improving space-time Code Performance in Slow Fading Channels using Reconfigurable Antennas

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IEEE COMMUNICATIONS LETTERS 2012年第4期16卷 494-497页

作者： Martin, Philippa A. Smith, Peter J. Murch, Ross Univ Canterbury Dept Elect & Comp Engn Canterbury New Zealand Hong Kong Univ Sci & Technol Dept Elect & Comp Engn Hong Kong Hong Kong Peoples R China

space-time block codes typically only span a small number of time slots. However, error control coding spanning hundreds or thousands of symbol periods is often used with space-time coding. In this case, slow fading channels significantly degrade performance. In this letter, we show that performance can be significantly improved in slow fading conditions by using reconfigurable antennas. We propose switching the transmit antenna states during transmission so that the error control code experiences several different channel conditions over the transmission period. Hence, it can achieve higher diversity and the superior performance expected of a faster fading channel due to reconfigurable antenna state switching. If we also allow the receiver to select the reconfigurable receive antenna states based on channel energy, then an antenna state selection gain is also achieved.

关键词： Reconfigurable antennas space time coding MIMO

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Blind Channel Estimation for STBC Systems Using Higher-Order Statistics

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2011年第2期10卷 495-505页

作者： Choqueuse, Vincent Mansour, Ali Burel, Gilles Collin, Ludovic Yao, Koffi Univ Brest Lab STICC UEB UMR CNRS 3192CS 93837 F-29238 Brest 3 France Curtin Univ Dept Elect & Comp Engn Perth WA Australia

This paper describes a new blind channel estimation algorithm for space-time Block Coded (STBC) systems. The proposed method exploits the statistical independence of sources before space-time encoding. The channel matrix is estimated by minimizing a kurtosis-based cost function after Zero-Forcing equalization. In contrast to subspace or Second-Order Statistics (SOS) approaches, the proposed method is more general since it can be employed for the general class of linear STBCs including Spatial Multiplexing, Orthogonal, quasi-Orthogonal and Non-Orthogonal STBCs. Furthermore, unlike other approaches, the method does not require any modification of the transmitter and, consequently, is well-suited for non-cooperative context. Numerical examples corroborate the performance of the proposed algorithm.

关键词： MIMO space time coding channel estimation independent component analysis higher-order statistics

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Design of diagonal algebraic space time codes with 8-star-PSK signals

Design of diagonal algebraic space time codes with 8-star-PS...

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14th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications

作者： Fan, PY Tsing Hua Univ Dept Elect Engn State Key Lab Microwave & Digital Commun Beijing 100084 Peoples R China

ISBN: (纸本)7505350668

Diagonal algebraic space time (DAST) block codes was proved to outperform the codes from orthogonal design with the equivalent spectral efficiency when the number of transmit antennas employed is larger than 2. However, due to the limitation on the signal constellation with complex integer points, no good 3bits/symbol DAST block code was not given previously. In this paper, we propose a general form of 8-star-PSK constellations with integer points and present some theoretical results on the performance of the equivalent 8-star-PSK modulations. By using our proposed 8-star-PSKs, we present a searching algorithm to construct optimal DAST codes with 3 bits per symbol under some criteria and investigate their performances. over flat Rayleigh fading channels.

关键词： space time coding algebraic coding Rayleigh fading channel multiple antennas

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Research and Simulation of MIMO-OFDM Wireless Communication System

Research and Simulation of MIMO-OFDM Wireless Communication ...

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International Forum on Information Technology and Applications (IFITA 2009)

作者： Jiang Xuehua Chen Peijiang Linyi Normal Univ Sch Engn Linyi 276000 Shandong Peoples R China

ISBN: (纸本)9780769536002

A simple MIMO-OFDM wireless communication system is constructed based on the analysis of the technical principles and the system models of the MIMO technology and the OFDM technology. The system combines the MIMO system and the OFDM system together, space-time coding is done in the transmitter firstly, the signal is launched after OFDM modulated, and the process of the receiver is the inverse process of the transmitter. The system performance is simulated by using the software MATLAB, the experimental result shows that the MIMO-OFDM wireless communication system has better performance when the antenna number is very large and the other conditions are identical, but the system performance will reduce if the carrier number increases.

关键词： wireless communication MIMO OFDM space time coding

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time-switched space-time Coded OFDM over time-varying Channels

Time-switched Space-time Coded OFDM over Time-varying Channe...

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6th International ICST Conference on Communications and Networking in China (CHINACOM)

作者： Jin, Jiyu Jin, Guiyue Wang, Zhisen Dalian Polytech Univ Sch Informat Sci & Engn Dalian Peoples R China

ISBN: (纸本)9781457701016

In this paper, we propose a time-switched space-time coded orthogonal frequency division multiplexing scheme over time-varying channels. The base station can use the proposed TSST-OFDM scheme with only two power amplifiers for four transmit antennas. For a given space-time code, we show that the signal to inter-antenna interference ratio is a function of Doppler frequency in time-varying channels. The proposed scheme not only gets time-switched diversity and lower decoding complexity, but also less sensitive to the time-varying channels, hence it exhibits better performance than quasi-orthogonal space-time coded scheme.

关键词： MIMO OFDM time-switched Transmit Diversity space time coding time-varying Channel

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Uplink single-user MIMO for 3GPP LTE

Uplink single-user MIMO for 3GPP LTE

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18th IEEE International Symposium on Personal, Indoor and Mobile Radio Communication

作者： Grieco, Donald M. Pan, Kyle Jung-Lin Olesen, Robert Lind Shah, Nirav InterDigital Commun Corp Melville NY USA

ISBN: (纸本)9781424411436

In this paper a multiple-input multiple-output (MIMO) scheme proposed for single carrier frequency division multiple access (SC-FDMA) system is described. Transmit and receive algorithms are developed for SC-FDMA MIMO systems. A spatial precoding closed-loop transmit beamforming (TxBF) algorithm for SC-FDMA MIMO system which uses singular value decomposition (SVD) at the transmitter and linear minimum mean square error (LMMSE) equalization at the receiver is described. Quantization and feedback schemes to support closed-loop operation are discussed. The PAPR effects and a mitigation approach are presented. Simulation results are shown for throughput vs. signal-to-noise ratio (SNR). The performance for this new TxBF algorithm is compared to Single-Input-Multiple Output (SIMO) performance. Also, single and dual-codeword performance is considered.

关键词： MIMO beamforming pre-coding SC-FDMA diversity space time coding space frequency coding feedback complexity PAPR

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MIMO-OFDM: Maximum Diversity Using Maximum Likelihood Detector

MIMO-OFDM: Maximum Diversity Using Maximum Likelihood Detect...

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10th International Conference on Communications (COMM)

作者： Sahrab, Ammar Ali Marghescu, Ion Politehn Univ Bucharest Romania

ISBN: (纸本)9781479923854

Multiple-Input Multiple-Output (MIMO) systems offer considerable increase in data throughput and link range without additional bandwidth or transmit power by using several antennas at transmitter and receiver to improve wireless communication system performance. At the same time, Orthogonal Frequency Division Multiplexing (OFDM) has becoming a very popular multi-carrier modulation technique for transmission of signals over wireless channels. OFDM eliminate Inter-Symbol-Interference (ISI) and allows the bandwidth of subcarriers to overlap without Inter Carrier Interference (ICI). A MIMO-OFDM modulation technique can achieve reliable high data rate transmission over broadband wireless channels. This paper deals with the analysis of a MIMO-OFDM system by using a MATLAB program. The performance of the system is evaluated on the basis of Bit Error Rate (BER) and Minimum Mean Square Error (MMSE) level.

关键词： MIMO-OFDM channel estimation multipath propagation MMSE diversity spatial multiplexing space time coding

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Model and Simulation of Channel Capacity for MIMO Wireless Navigation System

Model and Simulation of Channel Capacity for MIMO Wireless N...

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4th International Conference on Wireless Communications, Networking and Mobile Computing

作者： Dong, Chengxi Wu, Dewei Liu, Haibo AF Engn Univ Telecommun Engn Inst Xian 710077 Peoples R China

ISBN: (纸本)9781424421077

In order to study the basis of information theory for MIMO wireless navigation system, channel capacity formula of MIMO system which uses multi-sending and multi-receiving antennas was deduced from point of view of information theory. With a circularly symmetric complex Gaussian Input signal vector and equally-distributed signal power through all the transmit antennas, a much higher capacity can be obtained compared to the traditional SISO system. Two typical MIMO systems corresponding to all 1's and the unit transmission matrix were modeled completely for their channel capacity, followed by our proposed virtual equivalent structures. The simulation results were also given to testify the MIMO channel capacity.

关键词： channel capacity MIMO wireless navigation system space time coding

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Study and Implementation of MIMO-OFDM System Based on Matlab

Study and Implementation of MIMO-OFDM System Based on Matlab

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International Conference on Information Technology and Computer Science

作者： Jiang Xuehua Chen Peijiang Linyi Normal Univ Sch Engn Linyi 276000 Shandong Peoples R China

ISBN: (纸本)9780769536880

Based on the analysis of the technical principles and the system model of the MIMO and OFDM technologies, a simple MIMO-OFDM wireless communication system is constructed. The system is composed of transmitter, channel, receiver, and so on. space-time coding is done in the transmitter, the signal is launched after OFDM modulation, and the process of the receiver is the inverse process of the transmitter. The system performance is simulated by using the software Matlab, the experiment result shows that the MIMO-OFDM wireless communication system has better performance when there are more antennas. But, with the increase of the carrier number, the system performance will reduce because of the interference between sub-carriers.

关键词： MIMO OFDM Matlab space time coding wireless communication

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