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Blind Channel Estimation in Orthogonally Coded MIMO-OFDM Systems: A Semidefinite Relaxation Approach

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2009年第6期57卷 2354-2364页

作者： Sarmadi, Nima Shahbazpanahi, Shahram Gershman, Alex B. Tech Univ Darmstadt Dept Commun Syst NTS D-64283 Darmstadt Germany Univ Ontario Inst Technol Fac Engn & Appl Sci Oshawa ON L1H 7K4 Canada

A new blind channel estimation approach for orthogonally coded multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems is proposed. The main idea of our technique is, using specific properties of the orthogonal space-time block codes (OSTBCs), to estimate the finite impulse response (FIR) channel parameters in the time domain instead of doing this in the frequency domain independently for each subcarrier. This results in a substantially improved parsimony of the channel parametric model as compared to the direct per subcarrier channel estimation methods and allows coherent processing across the subcarriers. It is shown that using the semidefinite relaxation (SDR) technique, our channel estimation problem can be approximated as a convex semidefinite programming (SDP) problem and, hence, can be solved efficiently using modern convex optimization methods. Our simulations validate the performance and/or computational complexity advantages of the proposed method as compared to some current state-of-the-art blind MIMO-OFDM channel estimation methods.

关键词： Channel estimation multiple-input multiple-output systems orthogonal frequency-division multiplexing semidefinite relaxation space-time block coding

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space-time block coded joint transmit/receive diversity in a frequency-nonselective Rayleigh fading channel

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IEICE TRANSACTIONS ON COMMUNICATIONS 2006年第8期E89B卷 2189-2195页

作者： Tomeba, Hiromichi Takeda, Kazuaki Adachi, Fumiyuki Tohoku Univ Grad Sch Engn Dept Elect & Commun Engn Sendai Miyagi 9808579 Japan

Antenna diversity is an effective technique for improving the transmission performance in a multi-path fading channel. Recently, transmit diversity has been attracting much attention since it can alleviate the complexity problem of the mobile terminals. Joint transmit diversity/receive diversity achieves a much improved transmission performance. In this paper, we propose a new space-time block coding algorithm for joint transmit/receive diversity, which requires the channel state information (CSI) only at the transmitter side. Unlike the conventional space-time transmit diversity (STTD), the space-time block coded joint transmit/receive diversity (STBC-JTRD) can use. arbitrary number of transmit antennas, while the number of receive antennas is limited to 4. STBC-JTRD achieves a larger diversity gain than joint STTD/receive antenna diversity. The bit error rate (BER) analysis in a frequency-nonselective Rayleigh fading channel is presented. The BER performance is evaluated and is confirmed by the computer simulation.

关键词： antenna diversity space-time block coding time-division duplex

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Unified Performance Analysis of Transmit Antenna Selection With OSTBC and Imperfect CSI Over Nakagami-m Fading Channels

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2018年第1期67卷 494-508页

作者： Yu, Xiangbin Xu, Weiye Leung, Shu-Hung Wang, Jiang Nanjing Univ Aeronaut & Astronaut Dept Elect Engn Nanjing 210016 Jiangsu Peoples R China Nanjing Inst Technol Sch Commun Engn Nanjing 211167 Jiangsu Peoples R China City Univ Hong Kong State Key Lab Millimeter Waves Hong Kong Hong Kong Peoples R China City Univ Hong Kong Dept Elect Engn Hong Kong Hong Kong Peoples R China Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai 201899 Peoples R China

Aunified error analysis of multi-antenna systems with orthogonal space-time block coding (OSTBC) using transmit antenna selection (TAS) over Nakagami-m channels in the presence of feedback delay and channel estimation error is presented, where the number of transmit antennas is arbitrarily selected. For imperfect channel state information (CSI), the Nakagami-m channel is modeled as the sum of Nakagami-(m) over cap channel and independent Gaussian channel error. By this model, accurate and closed-form approximate bit error rate (BER) expressions of TAS-OSTBC for M-ary quadrature amplitude modulation and M-ary phase-shift keying are derived by using the moment generating function of received SNR. With the approximate BER formula, the number of antennas to be selected for transmission can be adapted by minimizing the BER of the system with imperfect CSI. The diversity and coding gains of TAS-OSTBC with K receive antennas and M antennas selected from N transmit antennas for transmission are analyzed at high SNR. For noninteger m K, the upper and lower bounds of the diversity gain for different CSI and estimation error scenarios are derived. But for integer m K, the results indicate that the upper and lower bounds are equal achieving the full diversity order of m K N for perfect CSI, zero diversity order and partial diversity order of m M K for estimation error variance being fixed and being a decreasing function of average SNR, respectively. The coding gain is affected by M, N, K, Nakagami parameter m, code rate, modulation, and channel correlation coefficients. Simulation results verify the validity of the theoretical

关键词： Arbitrary number antenna selection estimation error feedback delay diversity Nakagami channel space-time block coding

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Bit error rate and outage analysis of an interference cancellation technique for cooperative spectrum sharing cognitive radio systems

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IET COMMUNICATIONS 2016年第12期10卷 1436-1443页

作者： Jain, Neha Vashistha, Ankush Bohara, Vivek Ashok Indraprastha Inst Informat Technol WiroCoMM Lab Elect & Commun Engn New Delhi 110020 India

In this study, an overlay spectrum sharing scheme has been proposed for a cognitive radio system. To achieve the desired quality of service for the licenced (i.e. primary) system and spectrum access for unlicenced (i.e. secondary) system, a three-phase cooperative decode and forward relaying is used. Furthermore, space-time block coding is used in order to cancel the interference at primary as well as secondary receiver. It has been shown that the proposed scheme helps in achieving diversity gain of three and two for primary and secondary systems, respectively. The performance of both primary and cognitive (secondary) system is appraised by deriving closed-form expression for bit error rate and outage probability. The theoretical and simulation results validate that the proposed scheme improves the performance of both systems as compared with the earlier proposed schemes.

关键词： cognitive radio interference suppression error statistics spread spectrum communication cooperative communication space-time block codes bit error rate outage analysis interference cancellation technique cooperative spectrum sharing cognitive radio system overlay spectrum sharing scheme three-phase cooperative decode and forward relaying space-time block coding outage probability

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An Open-Loop Adaptive space-time Transmit Scheme for Correlated Fading Channels

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IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING 2008年第2期2卷 147-158页

作者： Lin, Min Yang, Luxi Zhu, Wei-Ping Li, Min Southeast Univ Sch Informat Sci & Engn Nanjing 210096 Peoples R China Concordia Univ Dept Elect & Comp Engn Montreal PQ H3G 1M8 Canada

Recently, the combination of beamforming (BF) and space-time block coding (STBC) has been widely studied in wireless communications, and is recognized as an efficient means to improve the system performance. In this paper, an open-loop adaptive space-time transmit scheme for correlated fading channels is presented. A hybrid system combining adaptive BF with STBC is first developed based on the model of the equivalent scaled additive white Gaussian noise (AWGN) channel induced by STBC, in which the maximization of the output mean signal-to-noise ratio (SNR) and the minimization of the symbol error rate (SER) upper bound are used as the design criteria. Then, a method to efficiently calculate the downlink beamforming weight vectors from the uplink channel correlation matrix is presented, so that the feedback of channel statistics from the receiver to the transmitter can be avoided. The main benefit of the proposed scheme is that it can achieve a nearly optimal performance with low implementation complexity. Next, utilizing the Laplace transform, the SER performance of the system with the new transmit scheme is analyzed by considering the three most widely used modulations, namely, M-PAM, M-PSK and square M-QAM. Finally, analytical and simulation results are given to demonstrate the validity and superiority of the proposed method.

关键词： Adaptive beamforming correlated fading channel space-time block coding symbol error rate wireless communication

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Improved Linear Group Detection for Combined Spatial Multiplexing/STBC Systems

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IEEE TRANSACTIONS ON COMMUNICATIONS 2009年第11期57卷 3252-3257页

作者： Riera-Palou, Felip Femenias, Guillem Univ Balearic Isl Mobile Commun Grp Dept Math & Informat Mallorca 07122 Spain

Wireless architectures combining the use of spatial division multiplexing (SDM) and space-time block coding (STBC) have begun to appear in the latest communications standards. In recent years, different detection strategies for these schemes have been proposed which can be broadly categorised as group-based or direct-detection techniques. While the former class aims at separating the different STBC streams and then apply conventional simple Alamouti decoding, the latter type directly estimates the transmitted symbols without fully exploiting the Alamouti structure. Previous publications have shown that direct-detection outperform group-based detectors with the penalty of a higher computational complexity. This letter presents a unified view of the detection strategies for hybrid SDM/STBC systems and presents two new families of group-based detectors. It is shown that linear group detection, when properly implemented, attains the same performance as linear direct detectors at a significant lower complexity.

关键词： Spatial division multiplexing space-time block coding hybrid systems linear detectors

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Convergence Aspects of Autonomic Cooperative Networks

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INTERNATIONAL JOURNAL OF INFORMATION TECHNOLOGY AND WEB ENGINEERING 2011年第4期6卷 51-62页

作者： Wodczak, Michal Telcordia Technol Poznan Poland

The current efforts across industry and academia are to develop new paradigms that enable ubiquitous on-demand service provision. This aim may be achievable because of the envisaged deployment of cutting-edge technologies such as cooperative transmission. However, a real advancement is only attainable when autonomic system design principles are taken into account. Looking at the concept of the Relay Enhanced Cell, one may come across commonalities with Mobile Ad-hoc Networks. Especially in Local Area scenarios, Base Stations seem to resemble advanced Access Points, while fixed and movable Relay Nodes might be replaced by powerful mobile User Terminals. On top of it, Generic Autonomic Network Architecture would help accommodate the fact that network devices may expose autonomic cooperative behaviors, allowing them to play certain roles. Finally, such a network must interact with Operations Support System deployed by the network operator for uninterrupted, continued operation.

关键词： Autonomic Networking Convergence Aspects Cooperative Transmission Local Area Optimized Link State Routing Relay Enhanced Cell space-time block coding

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A New Design Criterion for Linear Receiver STBCs Based on Full-Rank spaces

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IEEE COMMUNICATIONS LETTERS 2015年第2期19卷 207-210页

作者： Tofigh, Sadegh Kermani, Hossein Momenaee Morsali, Alireza Shahid Bahonar Univ Kerman Dept Math & Comp Sci Kerman 76169133 Iran Shahid Bahonar Univ Kerman Dept Elect Engn Kerman 76169133 Iran

In this paper, we study linear receiver space-time block codes (L-STBCs). These codes are very important and applicable because the simplest decoders, namely, ZF and MMSE, can be implemented at the receiver to decode these codes. Design criterion of L-STBCs is the primary basis needed for research in this field. The only criterion put forth to date is based on two conditions on the equivalent channel matrix. In this paper, first, we propose a systematic guideline for determining the equivalent channel matrix of a wide range of L-STBCs, including all the existing L-STBCs, and then, we derive a new design criterion for these L-STBCs with only one condition on the code structure. In addition, we show that there is a strong connection between full-diversity L-STBCs and full-rank subspaces of matrices. Finally, L-STBCs with orthogonal equivalent channels are characterized.

关键词： space-time block coding multi-input-multi-output (MIMO) systems linear receiver orthogonal design full-rank subspaces

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BER Analysis of Square OSTBCs with LMMSE Channel Estimation in Arbitrarily Correlated Rayleigh Fading Channels

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IEEE COMMUNICATIONS LETTERS 2010年第7期14卷 626-628页

作者： Jacobs, Lennert Moeneclaey, Marc Univ Ghent Dept Telecommun & Informat Proc B-9000 Ghent Belgium

In this paper, we examine the bit error rate (BER) performance of square orthogonal space-time block codes (OSTBCs) under arbitrarily correlated Rayleigh fading channels. We consider a mismatched maximum-likelihood receiver that obtains the channel state information through pilot-based linear minimum mean-square error channel estimation. For PAM and QAM constellations, a closed-form approximation of the BER is presented, which yields very accurate BER results over a wide range of signal-to-noise ratios.

关键词： space-time block coding imperfect channel estimation error analysis correlated Rayleigh fading

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An efficient detector for combined space-time coding and layered processing

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IEEE TRANSACTIONS ON COMMUNICATIONS 2005年第9期53卷 1438-1442页

作者： Dai, L Sfar, S Letaief, KB Hong Kong Univ Sci & Technol Ctr Wireless Informat Technol Dept Elect & Elect Engn Hong Kong Hong Kong Peoples R China

Group layered space-time architecture (GLST) combines space-time block coding and layered space-time processing, where the transmit stream is partitioned into different groups, and in each group, space-time block coding is applied. In the traditional receiver of GLST, group detection is applied first to suppress the interference from other groups, and then decoding is performed for the desired group. In this letter, a novel detector is proposed in which the entire groups are decoded first, and then group detection is performed next. Theoretical analysis will demonstrate that the new detector can achieve a significant capacity gain compared with the traditional one. Simulation results will further show that the proposed detector can obtain at least 4 dB gain at a frame-error rate of 10(-2), for instance.

关键词： group detection layered space-time (LST) multiple-input/multiple-outpyt (MINIO) systems outage capacity space-time block coding

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