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Very-large-scale integration hardware implementation of adaptive space-time coding/spatial multiplexing switching

IET COMMUNICATIONS 2012年第10期6卷 1316-1325页

作者： Nurmi, W. Nooshabadi, S. Univ Turku Dept Informat Technol SF-20500 Turku Finland Michigan Technol Univ Dept Elect & Comp Engn Houghton MI 49931 USA

Multiple input multiple output (MIMO) techniques are widely employed in modern wireless systems. The most prominent approaches to MIMO communication are space-time coding (STC) and spatial multiplexing (SM). Less studied is a hybrid technique called adaptive MIMO switching (AMS), which may be employed by fixing the transmission rate and selecting between space-time block coding and SM transmission modes based on instantaneous channel conditions to achieve the most efficient link. This study presents a hardware implementations of a selector algorithm and a detector employing it. The detector is designed for a 2 x 2 MIMO system and was implemented on an Altera Cyclone II FPGA. In addition, two transmission protocols with decision feedback from the receiver to the transmitter via a low-rate feedback channel are introduced and the feasibility of switching for high-data-rate transmissions is discussed.

关键词： Communication switching automatic repeat request Protocols space division multiplexing telecommunication channels multiple input multiple output communication radio transmitters space-time codes Codes very-large-scale integration hardware implementation decision feedback low-rate feedback channel adaptive MIMO switching receiver field programmable gate arrays radio receivers MIMO system two transmission protocols spatial multiplexing switching space-time block coding protocols transmitter adaptive codes Altera Cyclone II FPGA adaptive space-time coding Radio links and equipment MIMO communication modern wireless systems

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Hybrid IRS and DFE Detection Scheme for MDL-Impaired Transmission With TAST coding

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JOURNAL OF LIGHTWAVE TECHNOLOGY 2019年第17期37卷 4251-4259页

作者： Hei, Yongqiang Li, Li Song, Weiting Shi, Guangming Gu, Huaxi Xidian Univ State Key Lab ISN Xian 710071 Shaanxi Peoples R China Xidian Univ Sch Elect Engn Xian 710071 Shaanxi Peoples R China

Linear threaded algebraic space-time (TAST) codes have shown potential advantage in mitigating the mode-dependent loss in the few-mode-fiber-based mode-division multiplexing (MDM) system. However, the maximum-likelihood (ML) detector employed at the receiver of the MDM system greatly suffers from exponential computational complexity. In this work, we first examine the necessity of space-time coding in the MDM system. On this basis, a new hybrid detection, which integrates the improved reduced-search (IRS) method and the decision feedback equalizer (DFE), is proposed for the TAST-assisted MDM system, in which DFE is employed to detect the more reliable tributaries to obtain a near-ML solution, while IRS is responsible for finding the best solution in the remaining set with a reduced number of candidates. Simulation results show that the proposed detection method can achieve near-optimal solutions and has a low computational complexity. Moreover, it has the attractive advantage of flexible adjustment in the tradeoff between system performance and computational complexity.

关键词： Mode-division multiplexing MIMO detection space-time block coding

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Performance comparisons of MIMO techniques with application to WCDMA systems

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EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2004年第5期2004卷 649-661页

作者： Li, CX Wang, XD Columbia Univ Dept Elect Engn New York NY 10027 USA

Multiple-input multiple-output (MIMO) communication techniques have received great attention and gained significant development in recent years. In this paper, we analyze and compare the performances of different MIMO techniques. In particular, we compare the performance of three MIMO methods, namely, BLAST, STBC, and linear precoding/decoding. We provide both an analytical performance analysis in terms of the average receiver SNR and simulation results in terms of the BER. Moreover, the applications of MIMO techniques in WCDMA systems are also considered in this study. Specifically, a subspace tracking algorithm and a quantized feedback scheme are introduced into the system to simplify implementation of the beamforming scheme. It is seen that the BLAST scheme can achieve the best performance in the high data rate transmission scenario;the beamforming scheme has better performance than the STBC strategies in the diversity transmission scenario;and the beamforming scheme can be effectively realized in WCDMA systems employing the subspace tracking and the quantized feedback approach.

关键词： BLAST space-time block coding linear precoding/decoding subspace tracking WCDMA

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Subspace approach to blind and semi-blind channel estimation for space-time block codes

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2005年第2期4卷 357-362页

作者： Ding, ZG Ward, DB Univ London Imperial Coll Sci Technol & Med Dept Elect & Elect Engn London SW7 2AZ England

A new approach to blind and semi-blind channel estimation for space-time block codes (STBCs) is presented. By exploiting the recently proposed generalized space-time block code framework, an STBC system is reduced from multiple-input multiple-output to a single-input multiple-output system. A conventional blind algorithm based on the subspace algorithm is then used to identify the channel impulse responses and achieve equalization. Simulation results demonstrate the performance of the proposed algorithm and a comparable scheme.

关键词： blind and semi-blind channel estimation equalization multiple-input multiple-output (MIMO) systems space-time block coding

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Performance analysis of two-user cooperative ARQ protocol over Rayleigh fading channel

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2015年第1期2015卷 1-6页

作者： Xiao, Hailin Ni, Ju Guilin Univ Elect Technol Sch Informat & Commun Guilin 541004 Guangxi Peoples R China Lib Guilin Univ Elect Technol Guilin 541004 Guangxi Peoples R China

In this paper, we present a two-user cooperative automatic repeat request (C-ARQ) protocol which combines cooperative diversity at the physical layer and ARQ at the link layer. In this scheme, distributed Alamouti space-time block coding (DASTBC) is applied to achieve cooperative diversity, and ARQ is used to improve the data link layer reliability. To analyze the performance of the proposed protocol, we derive the average frame error rate (FER) and throughput with multiple phase shift keying (MPSK) over a Rayleigh fading channel. Numerical simulation results show that the performance gain of average FER with ARQ retransmission is about 2 dB more than the case without ARQ retransmission in the same conditions. Moreover, the combined DASTBC and quadrature phase shift keying (QPSK) with ARQ retransmission will lead to an approximate 3 Mbits/s increase in transmission rate.

关键词： Cooperative communication Multiple phase shift keying ARQ space-time block coding

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Upper bounds on the BER performance of MTCM-STBC schemes over shadowed Rician fading channels

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EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2004年第9期2004卷 1238-1245页

作者： Uysal, M Georghiades, CN Univ Waterloo Dept Elect & Comp Engn Waterloo ON N2L 3G1 Canada Texas A&M Univ Dept Elect Engn College Stn TX 77843 USA

space-time block coding (STBC) provides substantial diversity advantages with a low decoding complexity. However, these codes are not designed to achieve coding gains. Outer codes should be concatenated with STBC to provide additional coding gain. In this paper, we analyze the performance of concatenated trellis-coded STBC schemes over shadowed Rician frequency-flat fading channels. We derive an exact pairwise error probability (PEP) expression that reveals the dominant factors affecting performance. Based on the derived PEP, in conjunction with the transfer function technique, we also present upper bounds on the bit error rate (BER), which are further shown to be tight through a Monte-Carlo simulation study.

关键词： space-time block coding trellis-coded modulation Rician fading channels shadowing pairwise error probability

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An adaptive CMMSE receiver for space-time block-coded CDMA systems in frequency-selective fading channels

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2004年第3期53卷 587-600页

作者： Jung, YH Hong, SC Kim, SR Lee, YH Samsung Adv Inst Technol i Networking Lab Kyonggi Do 449712 South Korea Samsung Elect Kyonggi Do 443742 South Korea ETRI Mobile Commun Lab Taejon 305350 South Korea Korea Adv Inst Sci & Technol Dept Elect Engn & Comp Sci Taejon 305701 South Korea

A technique that can suppress multiple-access interference (MAI) in space-time block-coded (STBC) multiple-input-multiple-output (MIMO) code-division multiple-access (CDMA) systems is developed. The proposed scheme, called a constrained minimum mean square error (CMMSE) receiver, is an extension of the CMMSE receiver for a single-input-single-output system to MIMO systems. It is shown that the complexity of the proposed CMMSE receiver is almost independent of the number of transmitter antennas. The advantage of the proposed receiver over the existing receivers for STBC CDMA systems is demonstrated by comparing the closed-form expressions of the signal-to-interference plus noise ratio and simulated bit error rates. The results indicate that the proposed CMMSE receiver can provide a significant performance improvement over the conventional receivers and that the gain achieved by suppressing the MAI can be larger than that from increasing the transmitter or receiver diversity.

关键词： adaptive interference mitigation code division multiple access (CDMA) constrained minimum mean square error (CMMSE) multiple-input-multiple-output (MIMO) space-time block coding

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Spatially Modulated Orthogonal space-time block Codes with Non-Vanishing Determinants

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IEEE TRANSACTIONS ON COMMUNICATIONS 2014年第1期62卷 85-99页

作者： Minh-Tuan Le Vu-Duc Ngo Hong-Anh Mai Xuan Nam Tran Di Renzo, Marco Hanoi Dept Sci & Technol Hanoi Vietnam HUST Sch Elect & Telecommun Hanoi Vietnam Le Quy Don Tech Univ Dept Elect & Commun Hanoi Vietnam Univ Paris 11 Lab Signaux & Syst Unite Mixte Rech 8506 CNRSEcole Super Elect F-91192 Gif Sur Yvette France

This paper proposes a multiple-input multiple-output (MIMO) transmission scheme for M-ary modulations, called Spatially Modulated Orthogonal space-time block coding (SM-OSTBC), based on the concept of Spatial Constellation (SC) codewords introduced by Le at el. [1]. In the proposed scheme, transmit codeword matrices are generated by multiplying SC matrices with codewords constructed from Orthogonal space-time block Codes (O-STBC). The maximum spectral efficiency of the proposed scheme is equal to (n(T) - 2+ log(2) M) bpcu, where n(T) is the number of transmit antennas and M is the modulation order. The SC matrices provide a means of carrying information bits together with the O-STBC codewords and allow the SM-OSTBC scheme to achieve second-order transmit diversity by satisfying the non-vanishing determinant property. A systematic method to design the SC codewords for an even number of transmit antennas greater than 3 is presented. A single-stream maximum-likelihood (ML) decoder, which requires a low computational complexity thanks to the structure of the SM-OSTBC codewords and to the orthogonality of the O-STBCs, and a sphere decoder with further reduced signal processing complexity are developed. The bit error rate (BER) performance of the proposed scheme is studied by using both theoretical union bound analysis and computer simulations. Finally, simulation results are presented in order to compare BER performance, energy efficiency and decoding complexity of the proposed scheme with those of several existing MIMO transmission schemes.

关键词： MIMO systems spatial modulation space-time block coding space-time block coded spatial modulation spatial constellation matrices

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A Quasi-Orthogonal Group space-time architecture to achieve a better diversity-multiplexing tradeoff

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2007年第4期6卷 1295-1307页

作者： Dai, Lin Sfar, Sana Letaief, Khaled B. Hong Kong Univ Sci & Technol Ctr Wireless Informat TEchnol Dept Elect Engn Hong Kong Hong Kong Peoples R China

Most existing MIMO (Multiput-Input Multiput-Output) schemes optimize only either the diversity gain or the multiplexing gain. To obtain a good tradeoff between these two, the Quasi-Orthogonal. Group space-time (QoGST) architecture is proposed, wherein the transmit stream is subgrouped but encoded via an inter-group space-time block encoder, with group interference suppression at the receiver. This paper also considers another combined space-time coiling and layered space-time architecture, which we refer to as Group Layered space-time (GLST), where space-time block coding is employed within each group. Under the assumption of Rayleigh fading and a prior perfect channel state information at the receiver, a performance analysis will demonstrate that both QoGST and GLST can achieve a good diversity-multiplexing tradeoff. QoGST is even superior to GLST. Simulation results will validate our analysis and further show that compared to the existent Layered space-time block Code (LSTBC) scheme, both QoGST and GLST can achieve a significant performance gain.

关键词： diversity-multiplexing tradeoff group detection layered space-time MIMO systems quasi-orthogonal group space-time space-time block coding

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Distributed differential space-time coding for wireless relay networks

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IEEE TRANSACTIONS ON COMMUNICATIONS 2008年第7期56卷 1092-1100页

作者： Jing, Yindi Jafarkhani, Hamid Univ Calif Irvine Dept Comp Sci & Elect Engn Irvine CA 92697 USA

Distributed space-time coding is a cooperative transmission scheme for wireless relay networks. With this scheme, antennas of the distributive relays work as transmit antennas of the sender and generate a space-time code at the receiver. It achieves the maximum diversity. Although the scheme needs no channel information at relays, it does require full channel information, both the channels from the transmitter to relays and the channels from relays to the receiver, at the receiver. In this paper, we propose a differential transmission scheme, which requires channel information at neither relays nor the receiver, for wireless relay networks. As distributed space-time coding can be seen as the counterpart of space-time coding in the network setting, this scheme is the counterpart of differential space-time coding. Compared to coherent distributed space-time coding, the differential scheme is 3dB worse. In addition, we show that Alamouti, square real orthogonal, and Sp(2) codes can be used differentially in networks with corresponding numbers of relays. We also propose distributed differential space-time codes that work for networks with any number of relays using circulant matrices.

关键词： wireless relay networks cooperative diversity differential transmission space-time block coding

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