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Spatial Modulation for Layered space-time coding Used in Image-Sensor-Based Visible Light Communication

IEICE TRANSACTIONS ON COMMUNICATIONS 2017年第6期E100B卷 932-940页

作者： Masuda, Keisuke Kamakura, Koji Chiba Inst Technol Dept Comp Sci Narashino Chiba 2758588 Japan

Spatial modulation (SM) is introduced into layered space-time coding (L-STC) used in image sensor (IS)-based visible light communication (VLC) systems. STC was basically investigated for extending the communication range of the IS-based VLC link [10], although it is out of the range when IS receivers are at the long distance from the LED array of the transmitter where the number of pixels capturing the transmitter on the image plane is less than the number of LEDs of the array. Furthermore, LSTC was done in [11] for increasing the reception rate with improving the pixel resolution while the receiver was approaching the transmitter. In this paper, SM is combined into L-STC by mapping additional information bits on the location of the pair of STC bit matrices of each layer. Experimental results show that additional SM bits are extracted with no error, without deteriorating the reception quality of and shrinking the transmission range of the original L-STC.

关键词： spatial modulation space-time coding visible light communication layered STC image sensor

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A turbo detection and sphere-packing-modulation-aided space-time coding scheme

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2007年第2期56卷 575-582页

作者： Alamri, Osamah Rashed Yeap, Bee Leong Hanzo, Lajos Univ Southampton Sch Elect & Comp Sci Southampton SO17 1BJ Hants England

A recently proposed space-time block-coding (STBC) signal-construction method that combines orthogonal design with sphere packing (SP), referred to here as STBC-SP, has shown useful performance improvements over Alamouti's conventional orthogonal design. In this contribution, we demonstrate that the performance of STBC-SP systems can be further improved by concatenating SP-aided modulation with channel coding and performing demapping as well as channel decoding iteratively. We also investigate the convergence behavior of this concatenated scheme with the aid of extrinsic-information-transfer charts. The proposed turbo-detected STBC-SP scheme exhibits a "turbo-cliff" at E-b/N-0 = 2.5 dB and provides E-b/N-0 gains of approximately 20.2 and 2.0 dB at a bit error rate of 10(-5) over an equivalent-throughput uncoded STBC-SP scheme and a turbo-detected quadrature phase shift keying (QPSK) modulated STBC scheme, respectively, when communicating over a correlated Rayleigh fading channel.(1)

关键词： EXIT charts iterative demapping multidimensional mapping space-time coding sphere packing turbo detection

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Adaptive space-time coding Using ARQ

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2015年第9期64卷 4331-4337页

作者： Makki, Behrooz Svensson, Tommy Eriksson, Thomas Alouini, Mohamed-Slim Chalmers Dept Signals & Syst S-41296 Gothenburg Sweden King Abdullah Univ Sci & Technol Dept Elect Engn Thuwal 239556900 Saudi Arabia

We study the energy-limited outage probability of the block space-time coding (STC)-based systems utilizing automatic repeat request (ARQ) feedback and adaptive power allocation. Taking the ARQ feedback costs into account, we derive closed-form solutions for the energy-limited optimal power allocation and investigate the diversity gain of different STC-ARQ schemes. In addition, sufficient conditions are derived for the usefulness of ARQ in terms of energy-limited outage probability. The results show that, for a large range of feedback costs, the energy efficiency is substantially improved by the combination of ARQ and STC techniques if optimal power allocation is utilized.

关键词： Automatic repeat request (ARQ) feedback cost green communication outage probability power allocation space-time coding

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On the robustness of space-time coding techniques based on a general space-time covariance model

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2006年第1期55卷 219-233页

作者： Younkins, LT Su, WF Liu, KJR Johns Hopkins Univ Appl Phys Lab Laurel MD 20723 USA SUNY Buffalo Dept Elect Engn Buffalo NY 14260 USA Univ Maryland Dept Elect & Comp Engn College Pk MD 20742 USA

The robustness of space-time coding techniques for wireless channels that exhibit both temporal and spatial correlation is investigated. A general space-time covariance model is developed and employed to evaluate the exact pairwise error probability for space-time block codes. The expressions developed for the pairwise error probability are used in conjunction with the union bound to determine an upper bound for the probability of a block error. The block error probability is evaluated for several space-time codes and for wireless channels that exhibit varying degrees of spatial and temporal correlation. Numerical results are presented for a two-dimensional Gaussian scatterer model which has been shown to be consistent with recent field measurements of wireless channels. The results demonstrate that the best-case wireless channel is uncorrelated in both space and time. Correlation between transmission paths, due to insufficient spacing of the transmit antennas or scatterers located in close proximity to the mobile, can result in a significant performance degradation. The conditions that result in uncorrelated transmission paths are quantified in terms of the effective scattering radius and the spacing of the transmit and receive antennas.

关键词： receiver diversity space-time coding transmitter diversity wireless channels wireless communications

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Error performance of serially concatenated space-time coding

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JOURNAL OF COMMUNICATIONS AND NETWORKS 2003年第2期5卷 135-140页

作者： Altunbas, I Yongacoglu, A Istanbul Tech Univ Elect & Elect Fac TR-34469 Istanbul Turkey Univ Ottawa Sch Informat Technol & Engn Ottawa ON K1N 6N5 Canada

In this paper, we investigate the error performance of a serially concatenated system using a nonrecursive convolutional code as the outer code and a recursive QPSK space-time trellis code as the inner code on quasi-static and rapid Rayleigh fading channels. At the receiver, we consider iterative decoding based on the maximum a posteriori (MAP) algorithm. The performance is evaluated by means of computer simulations and it is shown that better error performance can be obtained by using low complexity outer and/or inner codes and the Euclidean distance criterion based recursive space-time inner codes. We also obtain new systems with large number of trasmit and/or receive antennas providing good error performance.

关键词： digital communication information theory serial concatenated coding space-time coding iterative decoding

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Nested Tucker tensor decomposition with application to MIMO relay systems using tensor space-time coding (TSTC)

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SIGNAL PROCESSING 2016年 128卷 318-331页

作者： Favier, Gerard Fernandes, C. Alexandre R. de Almeida, Andre L. F. Univ Nice Sophia Antipolis Lab I3S CNRS Sophia Antipolis France Univ Fed Ceara Campus Sobral Fortaleza Ceara Brazil Univ Fed Ceara Dept Teleinformat Engn Fortaleza Ceara Brazil

The aim of this paper is twofold. In a first part, we present a new tensor decomposition that we call Tucker train decomposition or nested Tucker decomposition (NTD). NTD can be viewed as a particular case of tensor-train decomposition recently proposed for representing and approximating high-dimensional tensors in a compact way. NTD of a fourth-order tensor is more specially analysed in terms of parameter estimation and uniqueness issue. In a second part, We show that the use of a tensor space-time coding (TSTC) structure at both the source node and the relay node of a one-way two-hop multi input multi-output (MIMO) relay communication system leads to a nested Tucker decomposition of the fourth-order tensor formed by the signals received at the destination. Two semi-blind receivers are then proposed for jointly estimating the transmitted information symbols and the two individual relay channels. The first one is iterative, based on a three-step alternating least squares (ALS) algorithm, whereas the second one;denoted 2LSKP, is a closed-form solution based on the LS estimations of two Kronecker products. Two supervised receivers are also derived by using a (short) pilot-assisted closed form solution for calculating channel estimates. These estimates are exploited either for initializing the ALS receiver or for designing a zero-forcing (ZF) receiver. Extensive Monte Carlo simulation results are provided to demonstrate the performance of the proposed relay system. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Channel estimation Nested Tucker model MIMO systems Relay systems Semi-blind receivers space-time coding Symbol estimation Tensor decompositions Tensor coding

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Toward Sub-Terahertz: space-time coding Metasurface Transmitter for Wideband Wireless Communications

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ADVANCED SCIENCE 2023年第29期10卷 e2304278页

作者： Liu, Yujie Wang, Yu Fu, Xiaojian Shi, Lei Yang, Fei Luo, Jiang Zhou, Qun Yan Fu, Yuan Chen, Qi Dai, Jun Yan Zhang, Lei Cheng, Qiang Cui, Tie Jun Southeast Univ State Key Lab Millimeter Waves Nanjing 210096 Peoples R China Southeast Univ Inst Electromagnet Space Nanjing 210096 Peoples R China Hangzhou Dianzi Univ Sch Elect & Informat Hangzhou 310018 Peoples R China

A space-time coding metasurface (STCM) operating in the sub-terahertz band to construct new-architecture wireless communication systems is proposed. Specifically, a programmable STCM is designed with varactor-diode-tuned metasurface elements, enabling precise regulation of harmonic amplitudes and phases by adjusting the time delay and duty cycle of square-wave modulation signal loaded on the varactor diodes. Independent electromagnetic (EM) regulations in the space and time domains are achieved by STCM to realize flexible beam manipulations and information modulations. Based on these features, a sub-terahertz wireless communication link is constructed by employing STCM as a transmitter. Experimental results demonstrate that the STCM supports multiple modulation schemes including frequency-shift keying, phase-shift keying, and quadrature amplitude modulations in a wide frequency band. It is also shown that the STCM is capable of realizing wide-angle beam scanning in the range of & PLUSMN;45(o), which offers an opportunity for user tracking during the communication. Thus, the STCM transmitter with high device density and low power consumption can provide low-complexity, low-cost, low-power, and low-heat solutions for building the next-generation wireless communication systems in the sub-terahertz frequency and even terahertz band.

关键词： metasurface space-time coding sub-terahertz wireless communications

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On the capacity of certain space-time coding schemes

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EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2002年第5期2002卷 447-458页

作者： Papadias, CB Foschini, GJ Bell Labs Lucent Technol Global Wireless Syst Res Dept Holmdel NJ 07733 USA

We take a capacity view of a number of different space-time coding (STC) schemes. While the Shannon capacity of multiple-input multiple-output (MIMO) channels has been known for a number of years now, the attainment of these capacities remains a challenging issue in many cases. The introduction of space-time coding schemes in the last 2-3 years has, however, begun paving the way towards the attainment of the promised capacities. In this work we attempt to describe what are the attainable information rates of certain STC schemes, by quantifying their inherent capacity penalties. The obtained results, which are validated for a number of typical cases, cast some interesting light on the merits and tradeoffs of different techniques. Further, they point to future work needed in bridging the gap between the theoretically expected capacities and the performance of practical systems.

关键词： MIMO systems space-time coding Bell labs Layered space time (BLAST) space-time spreading (STS) channel capacity space-time processing (STP) transmit diversity

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Distributed space-time coding in wireless relay networks

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2006年第12期5卷 3524-3536页

作者： Jing, Yindi Hassibi, Babak Univ Calif Irvine Irvine CA 92697 USA CALTECH Dept Elect Engn Pasadena CA 91125 USA

We apply the idea of space-time coding devised for multiple-antenna systems to the problem of communications over a wireless relay network with Rayleigh fading channels. We use a two-stage protocol, where in one stage the transmitter sends information and in the other, the relays encode their received signals into a "distributed" linear dispersion (LD) code, and then transmit the coded signals to the receive node. We show that for high SNR, the pairwise error probability (PEP) behaves as (log P/P)(min{T,R}), with T the coherence interval, that is, the number of symbol periods during which the channels keep constant, R the number of relay nodes, and P the total transmit power. Thus, apart from the log P factor, the system has the same diversity as a multiple-antenna system with R transmit antennas, which is the same as assuming that the R relays can fully cooperate and have full knowledge of the transmitted signal. We further show that for a network with a large number of relays and a fixed total transmit power across the entire network, the optimal power allocation is for the transmitter to expend half the power and for the relays to collectively expend the other halt We also show that at low and high SNR, the coding gain is the same as that of a multiple-antenna system with R antennas. However, at intermediate SNR, it can be quite different, which has implications for the design of distributed space-time codes.

关键词： space-time coding multiple-antenna systems wireless relay networks Rayleigh fading channels

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Performance Analysis and Optimization of the Relay Multicast System with space-time coding

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2014年第9期E97A卷 2005-2010页

作者： Wang, Nan Chen, Ming Dai, Jianxin Wu, Xia Southeast Univ Natl Mobile Commun Res Lab Nanjing 201196 Jiangsu Peoples R China

In a sector of a single cell, due to the fading characteristic of wireless channels, several decode-and-forward relay stations are deployed to form a two-hop relay-assisted multicast system. We propose two schemes for the system, the first scheme combines the use of space-time code and distributed space-time code (DSTC), and the second one combines the use of DSTC and maximum ratio combining. We give an outage probability analysis for both of them. Based on this analysis, we manage to maximize the spectral efficiency under a preset outage probability confinement by finding out the optimal power allocation and relay location strategies. We use genetic algorithms to verify our analysis and numerical results show that the schemes proposed by us significantly outperform the scheme in previous work. We also show the effect of path loss exponent on the optimal strategy.

关键词： relay multicast system space-time coding performance analysis relay location power allocation

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