orthogonalspace-timeblock coding (STBC) offers linear-complexity one-shot maximum-likelihood (ML) reception when the channel coefficients are known to the receiver. However, when the channel coefficients are unknown...
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ISBN:
(纸本)9781424429257
orthogonalspace-timeblock coding (STBC) offers linear-complexity one-shot maximum-likelihood (ML) reception when the channel coefficients are known to the receiver. However, when the channel coefficients are unknown, the optimal receiver takes the form of sequence detection. In this work, we prove that ML noncoherent sequence detection can always be performed in polynomial time with respect to the block length for orthogonal STBC and Rayleigh distributed channel coefficients. Using recent results on efficient maximization of reduced-rank quadratic forms over finite alphabets, we develop a novel algorithm that performs ML noncoherent orthogonal STBC detection with polynomial complexity in the block length. The order of the polynomial complexity of the proposed receiver is determined by the number of transmit and receive antennas.
orthogonalspace-timeblock coding (STBC) offers linear-complexity one-shot maximum-likelihood (ML) reception when the channel coefficients are known to the receiver. However, when the channel coefficients are unknown...
详细信息
ISBN:
(纸本)9781424429257
orthogonalspace-timeblock coding (STBC) offers linear-complexity one-shot maximum-likelihood (ML) reception when the channel coefficients are known to the receiver. However, when the channel coefficients are unknown, the optimal receiver takes the form of sequence detection. In this work, we prove that ML noncoherent sequence detection can always be performed in polynomial time with respect to the block length for orthogonal STBC and Rayleigh distributed channel coefficients. Using recent results on efficient maximization of reduced-rank quadratic forms over finite alphabets, we develop a novel algorithm that performs ML noncoherent orthogonal STBC detection with polynomial complexity in the block length. The order of the polynomial complexity of the proposed receiver is determined by the number of transmit and receive antennas.
Recently there has been growing interest in employing the orthogonal space-time block codes (OSTBCs) for blind maximum-likelihood (ML) detection. Several independent works have suggested that OSTBCs are favorable spac...
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ISBN:
(纸本)1424407281
Recently there has been growing interest in employing the orthogonal space-time block codes (OSTBCs) for blind maximum-likelihood (ML) detection. Several independent works have suggested that OSTBCs are favorable space-timecodes from a blind receiver implementation standpoint. In this work we turn our attention to blind ML identifiability, with an emphasis on a special class of codes called the nonintersecting subspace (NIS) OSTBCs. We show a powerful property that NIS-OSTBCs are uniquely identifiable up to a sign for any nonzero channel. However, many existing OSTBCs are not NIS. We propose a code construction procedure that can convert an existing OSTBC to an NIS-OSTBC. Simulation result are provided to support our theoretical findings.
In this paper, we propose a QR-based detection scheme of orthogonal space-time block codes for very fast fading channels. The proposed detection scheme employs a QR decomposition on the channel matrix and minimizes no...
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ISBN:
(纸本)9780780393912
In this paper, we propose a QR-based detection scheme of orthogonal space-time block codes for very fast fading channels. The proposed detection scheme employs a QR decomposition on the channel matrix and minimizes noise enhancement which occurs in an existing detection scheme. The performance of the proposed detection scheme is evaluated by computer simulations for various very fast fading channels. It is shown that when the channel fading is very fast, the proposed detection scheme outperforms the existing detection scheme.
A memoryless linear precoder is designed for orthogonal space-time block codes (OSTBC) for improved performance over block-fading flat correlated Rayleigh fading multiple-input multiple-output (MIMO) channels. Origina...
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A memoryless linear precoder is designed for orthogonal space-time block codes (OSTBC) for improved performance over block-fading flat correlated Rayleigh fading multiple-input multiple-output (MIMO) channels. Original features of the proposed technique include 1) the precoder can handle both transmit and receive correlation, and 2) the precoder handles any arbitrary joint correlation structure, including the so-called Kronecker (non-Kronecker) correlation models. The precoder is designed to minimize a symbol error-based metric as function of the joint slowly-varying channel correlation coefficients, which are supposed to be known to the transmitter. Several useful properties of the optimal precoder are given, evidencing the impact of receive correlation on transmitter optimization in certain situations. An iterative fast-converging numerical optimization algorithm is proposed. Monte Carlo simulations over fading channels are used to validate our claims.
It is well known that the Alamouti scheme with two transmit antennas and one receive antennas is the only capacityachieving complex orthogonal space-time block code(OSTBC).The rate of complex OSTBC for systems with mo...
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ISBN:
(纸本)078039335X
It is well known that the Alamouti scheme with two transmit antennas and one receive antennas is the only capacityachieving complex orthogonal space-time block code(OSTBC).The rate of complex OSTBC for systems with more than two transmit antennas is always less than 1. Recently, a quasi orthogonal space-time block code(QSTBC) with four transmit antennas and one receive antenna was proposed, which has the ability to approach the capacity, although at the price of sacrificing part of the diversity gain. In this paper, we analyze the capacity of QSTBC with four transmit antennas and arbitrary number of receive antennas. We show that the portion of the capacity that the QSTBC can achieve decreases with the number of receive antennas, and the (4,1) configuration is the only capacity-approaching case. In the high signal-to-noise ratio regime, we calculate the limit portion of capacity of QSTBC, and find that it is fixed to 1/4 when the number of receive antennas is no less than four. Numerical simulations verify our conclusions.
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