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2005年无线通信、网络和移动计算国际会议

作者： Xiang-Quan Shi Yu-Feng Ruan Yong-Xin Guo Nanjing University of Science and Technology Nanjing Jiangsu P.R.China Institute for Infocomm Research Science Park Ⅱ Singapore

ISBN: (纸本)078039335X

In this paper, the performance of the space-time coding ultra wideband impulse radio system in a typical IEEE 802.15 multipath channel is studied. In the proposed scheme, only two transmit antennas and one receiver antenna are employed and no channel information feedback is needed. We investigate how the temporal and spatial diversity influence the multiple access performance and how the space-time coding technique is used to mitigate the multiple access interference (MAI) and the inter-symbol interference (ISI) thereby improves the bit error rate performance of the ultra wideband impulse radio system. Numerical results show that the space-time coding technique is an efficient means to improve the performance of ultra wideband impulse radio system under IEEE 802.15 multipath environment in both one single user and multi users environment.

关键词： ultra wideband impulse radio transmit diversity space-time coding IEEE 802.15 multipath

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Differential diversity-embedding space-time block coding for 2 and 4 transmit antennas

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2008年第7期7卷 2452-2457页

作者： Rabiei, Payam Al-Dhahir, Naofal Univ Texas Dallas Richardson TX 75083 USA

Diversity-Embedding space-time Block coding (DE-STBC), introduced in [1], enables Unequal Error Protection (UEP) using multiple transmit antennas. Even though these codes do not require channel state information (CSI) at the transmitter, they do need it at the receiver for decoding. A novel differential DE-STBC scheme is proposed in this paper to eliminate the need for channel estimation at the receiver which is especially costly with multiple transmit and receive antennas. Most previously proposed differential schemes in the literature are based on orthogonal STBC and hence are not applicable to the non-orthogonal family of DE-STBC considered in this paper.

关键词： diversity embedding differential detection decoding throughput unequal error protection space-time coding

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Transmit-antennae space-time block coding for generalized OFDM in the presence of unknown multipath

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2001年第7期19卷 1352-1364页

作者： Liu, ZQ Giannakis, GB Barbarossa, S Scaglione, A Univ Minnesota Dept Elect & Comp Engn Minneapolis MN 55455 USA Univ Roma La Sapienza Informat & Commun Dept I-00184 Rome Italy

Transmit antenna diversity has been exploited recently to develop high-performance space-time coders and simple maximum-likelihood decoders for transmissions over flat fading channels. Relying on block preceding, this paper develops generalized space-time coded multicarrier transceivers appropriate for wireless propagation over frequency-selective multipath channels, Multicarrier preceding maps the frequency-selective channel into a set of flat fading subchannels, whereas space-time encoding/decoding facilitates equalization and achieves performance gains by exploiting the diversity available with multiple transmit antennas, When channel state information is unknown at the receiver, it is acquired blindly based on a deterministic variant of the constant-modulus algorithm that exploits the structure of space-time block codes, To benchmark performance, the Cramer-Rao bound of channel estimates is also derived, System performance is evaluated both analytically and with simulations.

关键词： blind channel estimation multipath fading channels space-time coding transmit diversity

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Adaptive Buffer-Aided space-time coding for Multiple-Antenna Cooperative Wireless Networks

Adaptive Buffer-Aided Space-Time Coding for Multiple-Antenna...

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WSA 2015;19th International ITG Workshop on Smart Antennas

作者： Tong Peng Rodrigo C. de Lamare CETUC/PUC-RIO

In this work we propose an adaptive buffer-aided space-time coding scheme for cooperative wireless networks. A maximum likelihood receiver and adjustable code vectors are considered subject to a power constraint with an amplify-and-forward cooperation strategy. Each multiple-antenna relay is equipped with a buffer and is capable of storing the received symbols before forwarding them to the destination. We also present an adaptive relay selection and optimization algorithm, in which the instantaneous signal to noise ratio in each link is calculated and compared at the destination. An adjustable code vector obtained by a feedback channel at each relay is employed to form a space-time coded vector which achieves a higher coding gain than standard schemes. A stochastic gradient algorithm is developed to compute the parameters of the adjustable code vector with reduced computational complexity. Simulation results show that the proposed buffer-aided scheme and algorithm obtain performance gains over existing schemes.

关键词： Cooperative systems Buffer-aided relays spacetime codes Relay selection cooperative systems Wireless networks signal to noise ratios feedback channel space-time coding relay time coding destination TUNABLE coding gain Self tuning Codes

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Adaptive Distributed space-time coding for Cooperative MIMO Relaying Systems with Limited Feedback

Adaptive Distributed Space-Time Coding for Cooperative MIMO ...

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IEEE Vehicular Technology Conference

作者： Tong Peng Rodrigo C. de Lamare Anke Schmeink Communications Research Group Department of Electronics University of York York YO10 5DD UK TUMIC Research Centre RWTH Aachen University D-52056 Aachen Germany

ISBN: (纸本)9781467363365

An adaptive distributed space-time coding (DSTC) scheme is proposed for two-hop cooperative MIMO networks. Linear minimum mean square error (MMSE) receive filters and adjustable matrices subject to a power constraint are considered with an amplify-and-forward (AF) cooperation strategy. In the proposed DSTC scheme, an adjustable matrix obtained by a feedback channel is employed to transform the space-time coded matrix at the relay node. Linear MMSE expressions of the adjustable code matrices based on the mean square error (MSE) and the maximum likelihood (ML) criteria are derived. The effects of the limited feedback and the feedback errors on the performance are considered. A stochastic gradient (SG) algorithm is also developed with reduced computational complexity. The simulation results show that the proposed algorithms obtain significant performance gains as compared to existing DSTC schemes.

关键词： DSTC MIMO AF multiple input multiple output systems Mean square error air feed equipment space-time coding feedback channel TUNABLE Feedback matrices encoding matrix Relay systems time coding Trunk Node

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A Trace-Orthogonal Multi-User space-time coding

A Trace-Orthogonal Multi-User Space-Time Coding

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第三届IEEE无线通讯、网络技术暨移动计算国际会议

作者： Qinghua Ma Jianguo Liu Luxi Yang School of Information Science and Engineering Southeast University Nanjing 210096 China

In this paper, we propose a trace-orthogonal spacetime coding (TD-STC) for multi-user systems. Based on the flexibility of linear dispersive codes (LDC), we apply it to broadcast channels in multi-user systems. According to the transmission rates of user's, we adaptively construct the transmitting space-time coding matrix. At the same time, we give the design criterion of the space time coding for multi-user systems. At the receiver, exploiting the characteristic of trace orthogonal, the complexity of decoder based on MMSE criterion will not increase apparently. Compared with orthogonal spacetime coding (OSTC), our proposed TD-STC can greatly decrease the complexity of ML decoding instead of little performance loss. When in the lower SNR, the proposed scheme is better than the scheme when applying orthogonal space-time coding.

关键词： trace-orthogonal broadcast channels space-time coding

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Performance of space-time coding with Variablepower Adaptive Modulation in Fading Channel

Performance of Space-time Coding with Variablepower Adaptive...

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第三届IEEE无线通讯、网络技术暨移动计算国际会议

作者： Xiangbin Yu College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China

In this paper, a space-time coded adaptive MQAM scheme with variable power is developed for MIMO system. Under the target BER and average power constraint, the optimum SNR switching thresholds for the developed scheme are generated by using the Lagrange method, which can make the scheme maximize the spectrum efficiency (SE). Besides, the closed-form expressions for the SE and average BER of the scheme are derived. Simulation results show that our scheme is superior to the corresponding constant-power space-time coded adaptive MQAM scheme. Moreover, the SE and average BER from theory computation accords with those from the simulation results.

关键词： Adaptive modulation space-time coding variable powe MQAM Spectrum efficiency

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On channel orthogonalization using space-time block coding with partial feedback

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IEEE TRANSACTIONS ON COMMUNICATIONS 2006年第6期54卷 1121-1130页

作者： Milleth, J. Klutto Giridhar, K. Jalihal, Devendra Indian Inst Technol Dept Elect Engn Telecommun & Comp Networks Grp Madras 600036 Tamil Nadu India

Orthogonal space-time block codes (OSTBCs) yield full diversity gain even while requiring only a linear receiver. Such full-rate (rate-one) orthogonal designs are available for complex symbol constellations only for N = 2 transmit antennas. In this paper, we propose a new family of full-rate space-time block codes (STBCs) using a single parameter feedback for communication over Rayleigh fading channels for N = 3, 4 transmit antennas and M receive antennas. The proposed rate-one codes achieve full diversity, and the performance is similar to maximum receiver ratio combining. The decoding complexity of these codes are only linear even while performing maximum-likelihood decoding. The partial channel information is a real phase parameter that is a function of all the channel gains, and has a simple closed-form expression for N = 3, 4. This feedback information enables us to derive (channel) orthogonal designs starting from quasi-orthogonal STBCs. The feedback complexity is significantly lower than conventional closed-loop transmit beamforming. We compare the proposed codes with the open-loop OSTBCs and also with the closed-loop equal gain transmission (EGT) scheme which uses equal power loading on all antennas. Simulated error-rate performances indicate that the proposed channel orthogonalized STBCs significantly outperform the open-loop orthogonal designs, for the same spectral efficiency. Moreover, even with significantly lower feedback and computational complexity, the proposed scheme outperforms the EGT technique for M > N.

关键词： closed-loop space-time block code (STBQ multiple-input multiple-output (MIMO) systems partial feedback space-time coding transmit diversity

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Tensor space-time (TST) coding for MIMO wireless communication systems

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SIGNAL PROCESSING 2012年第4期92卷 1079-1092页

作者： Favier, Gerard da Costa, Michele N. de Almeida, Andre L. F. Romano, Joao Marcos T. Univ Nice Sophia Antipolis CNRS Lab I3S Sophia Antipolis France Univ Campinas UNICAMP DSPCom Lab Campinas SP Brazil Univ Fed Ceara GTEL Wireless Telecom Res Grp Fortaleza Ceara Brazil

In this paper, we propose a tensor space-time (TST) coding for multiple-input multiple-output (MIMO) wireless communication systems. The originality of TST coding is that it allows spreading and multiplexing the transmitted symbols, belonging to R data streams, in both space (antennas) and time (chips and blocks) domains, owing the use of two (stream- and antenna-to-block) allocation matrices. This TST coding is defined in terms of a third-order code tensor admitting transmit antenna, data stream and chip as modes. Assuming flat Rayleigh fading propagation channels, the signals received by K receive antennas during P time blocks, composed of N symbol periods each, with J chips per symbol, form a fourth-order tensor that satisfies a new constrained tensor model, called a PARATUCK-(2,4) model. Conditions for identifiability and uniqueness of this model are established, and a performance analysis of TST coding is made, before presenting a blind receiver for joint channel estimation and symbol recovery. Finally, some simulation results are provided to evaluate the performance of this receiver. (C) 2011 Elsevier B.V. All rights reserved.

关键词： Channel estimation MIMO systems PARATUCK model space-time coding Symbol estimation Tensor modeling

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space-time modulation and coding over transmit correlated fading channels

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2004年第5期3卷 1405-1410页

作者： Godbout, M Leib, H McGill Univ Dept Elect & Comp Engn Montreal PQ H3A 2A7 Canada

Multi-dimensional space-time modulation schemes can be classified by the manner in which signal dimensions are shared among transmit antennas. In aggregate transmit antenna (ATA) systems, a generalization of Tarokh, Seshadri, Calderbank's (TSC) approach, there is total sharing of dimensions. In orthogonal transmit antenna (OTA) systems, a generalization of many traditional diversity schemes, there is no sharing of dimensions. In partially orthogonal transmit antennas (POTA), a combination of ATA with OTA, subsets of available dimensions are shared by subsets of transmit antennas. This letter considers such coded schemes for spatially correlated fading channels. Over strongly transmit correlated channels, in addition to coding and diversity gains, ATA and POTA can harvest a transmit beamforming-like gain. This letter presents a scheme, POTARep, designed to provide beamforming-like gain as well as diversity and coding gains, yielding improved performance over a highly transmit correlated channel.

关键词： antenna arrays beam forming fading channels multiple input multiple output (MIMO) systems space-time coding

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