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Helmut Bölcskei - One of the best experts on this subject based on the ideXlab platform.

  • selective fading multiple access mimo channels diversity multiplexing tradeoff and dominant outage event regions
    IEEE Transactions on Information Theory, 2012
    Co-Authors: Philippe Coronel, M Gartner, Helmut Bölcskei
    Abstract:

    We establish the optimal diversity-multiplexing (DM) tradeoff for coherent selective-fading multiple-access MIMO channels and provide corresponding Code design criteria. As a byproduct, on the conceptual level, we find an interesting relation between the DM tradeoff framework and the notion of dominant error event regions, first introduced in the AWGN case by Gallager, IEEE Trans. IT, 1985. This relation allows us to accurately characterize the error mechanisms in MIMO fading multiple-access channels. In particular, we find that, for a given rate tuple, the maximum achievable diversity order is determined by a single outage event that dominates the total error probability exponentially in SNR. Finally, we examine the distributed Space-Time Code construction proposed by Badr and Belfiore, Int. Zurich Seminar on Commun., 2008, using the Code design criteria derived in the present paper.

  • selective fading multiple access mimo channels diversity multiplexing tradeoff and dominant outage event regions
    arXiv: Information Theory, 2009
    Co-Authors: Pedro Coronel, M Gartner, Helmut Bölcskei
    Abstract:

    We establish the optimal diversity-multiplexing (DM) tradeoff for coherent selective-fading multiple-access MIMO channels and provide corresponding Code design criteria. As a byproduct, on the conceptual level, we find an interesting relation between the DM tradeoff framework and the notion of dominant error event regions, first introduced in the AWGN case by Gallager, IEEE Trans. IT, 1985. This relation allows us to accurately characterize the error mechanisms in MIMO fading multiple-access channels. In particular, we find that, for a given rate tuple, the maximum achievable diversity order is determined by a single outage event that dominates the total error probability exponentially in SNR. Finally, we examine the distributed Space-Time Code construction proposed by Badr and Belfiore, Int. Zurich Seminar on Commun., 2008, using the Code design criteria derived in this paper.

  • ICASSP - Space-Time signaling and frame theory
    2001 IEEE International Conference on Acoustics Speech and Signal Processing. Proceedings (Cat. No.01CH37221), 2001
    Co-Authors: Robert W Heath, Helmut Bölcskei, Arogyaswami J. Paulraj
    Abstract:

    Wireless systems with multiple transmit and receive antennas (MIMO systems) provide high capacity due to the plurality of modes available in the channel. Previous Code designs for MIMO systems have focused primarily on multiplexed signaling for high data rate or diversity signaling for high link reliability. Based on Ganesan and Stoica (2000) and Hassibi and Hochwald (2000), and using results from frame theory, we present a MIMO Space-Time Code design which bridges the gap between multiplexing and diversity and performs well both in terms of ergodic capacity as well as error-probability. In particular, we demonstrate that designs performing well from an ergodic capacity point of view do not necessarily perform well from an error probability point of view. Simulations illustrate performance of the proposed Codes in narrowband MIMO Rayleigh fading channels.

  • space time signaling and frame theory
    International Conference on Acoustics Speech and Signal Processing, 2001
    Co-Authors: Robert W Heath, Helmut Bölcskei, Arogyaswami J. Paulraj
    Abstract:

    Wireless systems with multiple transmit and receive antennas (MIMO systems) provide high capacity due to the plurality of modes available in the channel. Previous Code designs for MIMO systems have focused primarily on multiplexed signaling for high data rate or diversity signaling for high link reliability. Based on Ganesan and Stoica (2000) and Hassibi and Hochwald (2000), and using results from frame theory, we present a MIMO Space-Time Code design which bridges the gap between multiplexing and diversity and performs well both in terms of ergodic capacity as well as error-probability. In particular, we demonstrate that designs performing well from an ergodic capacity point of view do not necessarily perform well from an error probability point of view. Simulations illustrate performance of the proposed Codes in narrowband MIMO Rayleigh fading channels.

  • Performance of Space-Time Codes in the presence of spatial fading correlation
    Conference Record of the Thirty-Fourth Asilomar Conference on Signals Systems and Computers (Cat. No.00CH37154), 2000
    Co-Authors: Helmut Bölcskei, Arogyaswami J. Paulraj
    Abstract:

    Previous work on Space-Time coding has been restricted to the idealistic case of uncorrelated spatial fading. In practice, however insufficient antenna spacing or lack of scattering cause the individual antennas to be correlated. In this paper we study the impact of spatial fading correlation on the performance of Space-Time Codes. In particular we quantify the loss in diversity gain and coding gain as a function of angle spread and antenna spacing. We furthermore show that if a Space-Time Code achieves full diversity in the uncorrelated case, the diversity order achieved in the correlated case is given by the product of the rank of the transmit correlation matrix and the rank of the receive correlation matrix. Finally, we provide simulation results demonstrating the impact of spatial fading correlation on the symbol error rate of Space-Time Codes.

Arumugam Nallanathan - One of the best experts on this subject based on the ideXlab platform.

  • delay tolerant distributed linear convolutional space time Code with minimum memory length under frequency selective channels
    IEEE Transactions on Wireless Communications, 2009
    Co-Authors: Zhimeng Zhong, Arumugam Nallanathan
    Abstract:

    In cooperative communication networks, the performance of distributed Space-Time Code will be severely degraded if the timing synchronization among relay nodes is not perfect. In this letter, we propose a systematic construction of the so called distributed linear convolutional Space-Time Code (DLCSTC) for multipath fading channels that does not require the synchronization assumption. We derive sufficient conditions on the Code design such that the full cooperative and multipath diversities can be achieved under the minimum memory length constraint. Then we design DLCSTCs that both have the traceorthonormality property and achieve the full diversity. We show that the proposed Codes can also achieve the full diversity for asynchronous cooperative communications with ZF, MMSE and MMSE-DFE receivers under frequency-selective channels. Finally, various numerical examples are provided to corroborate the analytical studies.

  • ICC - Delay-Tolerant Distributed Linear Convolutional Space-Time Code Under Frequency-Selective Channels
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: Zhimeng Zhong, Arumugam Nallanathan
    Abstract:

    In cooperative communication networks, the performance of the distributed Space-Time Code (DSTC) will be severely degraded if the timing synchronization among relay nodes are not perfect. In this paper, we propose a systematic construction of the so called distributed linear convolutional Space-Time Code (DLCSTC) for multipath fading channels that does not require the synchronization assumption. We derive sufficient conditions on the Code design such that the full cooperative and multipath diversities can be achieved under the minimum memory length constraint. Then we design DLCSTCs that both have the trace-orthonormality property and achieve the full diversity. We also study the diversity property of the DLCSTC with suboptimal receivers. We show that the proposed Codes can also achieve the full diversity for asynchronous cooperative communications with ZF, MMSE and MMSE-DFE receivers under frequency-selective channels. Finally, various numerical examples are provided to corroborate the analytical studies.

Zhimeng Zhong - One of the best experts on this subject based on the ideXlab platform.

  • delay tolerant distributed linear convolutional space time Code with minimum memory length under frequency selective channels
    IEEE Transactions on Wireless Communications, 2009
    Co-Authors: Zhimeng Zhong, Arumugam Nallanathan
    Abstract:

    In cooperative communication networks, the performance of distributed Space-Time Code will be severely degraded if the timing synchronization among relay nodes is not perfect. In this letter, we propose a systematic construction of the so called distributed linear convolutional Space-Time Code (DLCSTC) for multipath fading channels that does not require the synchronization assumption. We derive sufficient conditions on the Code design such that the full cooperative and multipath diversities can be achieved under the minimum memory length constraint. Then we design DLCSTCs that both have the traceorthonormality property and achieve the full diversity. We show that the proposed Codes can also achieve the full diversity for asynchronous cooperative communications with ZF, MMSE and MMSE-DFE receivers under frequency-selective channels. Finally, various numerical examples are provided to corroborate the analytical studies.

  • ICC - Delay-Tolerant Distributed Linear Convolutional Space-Time Code Under Frequency-Selective Channels
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: Zhimeng Zhong, Arumugam Nallanathan
    Abstract:

    In cooperative communication networks, the performance of the distributed Space-Time Code (DSTC) will be severely degraded if the timing synchronization among relay nodes are not perfect. In this paper, we propose a systematic construction of the so called distributed linear convolutional Space-Time Code (DLCSTC) for multipath fading channels that does not require the synchronization assumption. We derive sufficient conditions on the Code design such that the full cooperative and multipath diversities can be achieved under the minimum memory length constraint. Then we design DLCSTCs that both have the trace-orthonormality property and achieve the full diversity. We also study the diversity property of the DLCSTC with suboptimal receivers. We show that the proposed Codes can also achieve the full diversity for asynchronous cooperative communications with ZF, MMSE and MMSE-DFE receivers under frequency-selective channels. Finally, various numerical examples are provided to corroborate the analytical studies.

Tolga M Duman - One of the best experts on this subject based on the ideXlab platform.

  • performance analysis of mimo systems with antenna selection over quasi static fading channels
    IEEE Transactions on Vehicular Technology, 2003
    Co-Authors: Ali Ghrayeb, Tolga M Duman
    Abstract:

    We analyze the performance of multiple-input-multiple-output (MIMO) systems with antenna selection over quasi-static fading channels. The basic idea is that, for a given number of receive antennas, M, the receiver uses the best L out of the available M antennas where, typically, Lsquared Euclidean distance. For full-rank Space-Time Codes, we believe that this is a valid assumption, especially for the worst case Codeword pairs that dominate the performance at high SNR. Under this assumption, we show that the diversity order of the underlying Space-Time Code is maintained, whereas the coding gain deteriorates by a value upper bounded by 10log/sub 10/(M/L) dB. We provide semianalytical and simulation results that support our analysis.

  • performance analysis of mimo systems with antenna selection over quasi static fading channels
    International Symposium on Information Theory, 2002
    Co-Authors: Ali Ghrayeb, Tolga M Duman
    Abstract:

    We examine the performance of multiple-input/multiple-output (MIMO) systems with antenna selection. We show that regardless of the underlying Space-Time Code, the diversity gain is maintained whereas the coding gain deteriorates by a value upper bounded by 10 log/sub 10/ (M/L) dB when L out of M antennas are selected at the receiver.

Philippe Coronel - One of the best experts on this subject based on the ideXlab platform.

  • selective fading multiple access mimo channels diversity multiplexing tradeoff and dominant outage event regions
    IEEE Transactions on Information Theory, 2012
    Co-Authors: Philippe Coronel, M Gartner, Helmut Bölcskei
    Abstract:

    We establish the optimal diversity-multiplexing (DM) tradeoff for coherent selective-fading multiple-access MIMO channels and provide corresponding Code design criteria. As a byproduct, on the conceptual level, we find an interesting relation between the DM tradeoff framework and the notion of dominant error event regions, first introduced in the AWGN case by Gallager, IEEE Trans. IT, 1985. This relation allows us to accurately characterize the error mechanisms in MIMO fading multiple-access channels. In particular, we find that, for a given rate tuple, the maximum achievable diversity order is determined by a single outage event that dominates the total error probability exponentially in SNR. Finally, we examine the distributed Space-Time Code construction proposed by Badr and Belfiore, Int. Zurich Seminar on Commun., 2008, using the Code design criteria derived in the present paper.