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Bjorn Ottersten - One of the best experts on this subject based on the ideXlab platform.
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The Diversity Order of the Semidefinite Relaxation Detector
IEEE Transactions on Information Theory, 2008Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:In this paper, we consider the detection of binary (antipodal) signals transmitted in a spatially multiplexed fashion over a fading multiple-input-multiple-output (MIMO) channel and where the detection is done by means of semidefinite relaxation (SDR). The SDR detector is an attractive alternative to maximum-likelihood (ML) detection since the complexity is polynomial rather than exponential. Assuming that the channel matrix is drawn with independent identically distributed (i.i.d.) real-valued Gaussian entries, we study the receiver Diversity and prove that the SDR detector achieves the maximum possible Diversity. Thus, the error probability of the receiver tends to zero at the same rate as the optimal ML receiver in the high signal-to-noise ratio (SNR) limit. This significantly strengthens previous performance guarantees available for the semidefinite relaxation detector. Additionally, it proves that full Diversity detection is also possible in certain scenarios when using a noncombinatorial receiver structure.
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On the Maximal Diversity Order of Spatial Multiplexing with Transmit Antenna Selection
arXiv: Information Theory, 2007Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:Zhang et. al. recently derived upper and lower bounds on the achievable Diversity of an N_R x N_T i.i.d. Rayleigh fading multiple antenna system using transmit antenna selection, spatial multiplexing and a linear receiver structure. For the case of L = 2 transmitting (out of N_T available) antennas the bounds are tight and therefore specify the maximal Diversity Order. For the general case with L
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on the maximal Diversity Order of spatial multiplexing with transmit antenna selection
arXiv: Information Theory, 2007Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:Zhang et. al. recently derived upper and lower bounds on the achievable Diversity of an N_R x N_T i.i.d. Rayleigh fading multiple antenna system using transmit antenna selection, spatial multiplexing and a linear receiver structure. For the case of L = 2 transmitting (out of N_T available) antennas the bounds are tight and therefore specify the maximal Diversity Order. For the general case with L <= min(N_R,N_T) transmitting antennas it was conjectured that the maximal Diversity is (N_T-L+1)(N_R-L+1) which coincides with the lower bound. Herein, we prove this conjecture for the zero forcing and zero forcing decision feedback (with optimal detection Ordering) receiver structures.
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On the Maximal Diversity Order of Spatial Multiplexing With Transmit Antenna Selection
IEEE Transactions on Information Theory, 2007Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:Zhang recently derived upper and lower bounds on the achievable Diversity of an NR timesNT i.i.d. Rayleigh fading multiple antenna system using transmit antenna selection, spatial multiplexing and a linear receiver structure. For the case of L = 2 transmitting (out of NT available) antennas the bounds are tight and therefore specify the maximal Diversity Order. For the general case with L les min(NR ldrNT) transmitting antennas it was conjectured that the maximal Diversity is (NT-L+1)(NR-L+1) which coincides with the lower bound. Herein, we prove this conjecture for the zero forcing and zero forcing decision feedback (with optimal detection Ordering) receiver structures.
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The Diversity Order of the Semidefinite Relaxation Detector
arXiv: Information Theory, 2006Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:We consider the detection of binary (antipodal) signals transmitted in a spatially multiplexed fashion over a fading multiple-input multiple-output (MIMO) channel and where the detection is done by means of semidefinite relaxation (SDR). The SDR detector is an attractive alternative to maximum likelihood (ML) detection since the complexity is polynomial rather than exponential. Assuming that the channel matrix is drawn with i.i.d. real valued Gaussian entries, we study the receiver Diversity and prove that the SDR detector achieves the maximum possible Diversity. Thus, the error probability of the receiver tends to zero at the same rate as the optimal maximum likelihood (ML) receiver in the high signal to noise ratio (SNR) limit. This significantly strengthens previous performance guarantees available for the semidefinite relaxation detector. Additionally, it proves that full Diversity detection is in certain scenarios also possible when using a non-combinatorial receiver structure.
Won Mee Jang - One of the best experts on this subject based on the ideXlab platform.
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Diversity Order and coding gain of general Order rectangular qam in mimo relay with tas mrc in nakagami m fading
IEEE Transactions on Vehicular Technology, 2014Co-Authors: Won Mee JangAbstract:Recently, multiple-input-multiple-output (MIMO) relay networks have been an active area of research, particularly with combining single transmit antenna selection (TAS) and receiver maximal ratio combining (MRC). Moreover, general-Order rectangular quadrature amplitude modulation (QAM) has received much attention for its high spectral efficiency and flexible modulation scheme. However, the analytical performance of general-Order rectangular QAM has not been found in the literature for MIMO relay with TAS/MRC in Nakagami- m fading channels in spite of its practical usefulness. In addition, the analytical performance of general-Order rectangular QAM often comes with enormous computational complexity. Therefore, it is hardly possible to understand the analytical solution unless the symbol error probability (SEP) is plotted graphically. In this paper, we present the SEP of general-Order rectangular QAM in a MIMO relay with TAS/MRC using the sampling property of the delta impulse function. The SEP of MIMO relay networks is shown in terms of Diversity Order and coding gain. The proposed sampling method can also significantly reduce the computational complexity of the SEP of general-Order rectangular QAM.
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Diversity Order and Coding Gain of General-Order Rectangular QAM in MIMO Relay With TAS/MRC in Nakagami- $m$ Fading
IEEE Transactions on Vehicular Technology, 2014Co-Authors: Won Mee JangAbstract:Recently, multiple-input-multiple-output (MIMO) relay networks have been an active area of research, particularly with combining single transmit antenna selection (TAS) and receiver maximal ratio combining (MRC). Moreover, general-Order rectangular quadrature amplitude modulation (QAM) has received much attention for its high spectral efficiency and flexible modulation scheme. However, the analytical performance of general-Order rectangular QAM has not been found in the literature for MIMO relay with TAS/MRC in Nakagami- m fading channels in spite of its practical usefulness. In addition, the analytical performance of general-Order rectangular QAM often comes with enormous computational complexity. Therefore, it is hardly possible to understand the analytical solution unless the symbol error probability (SEP) is plotted graphically. In this paper, we present the SEP of general-Order rectangular QAM in a MIMO relay with TAS/MRC using the sampling property of the delta impulse function. The SEP of MIMO relay networks is shown in terms of Diversity Order and coding gain. The proposed sampling method can also significantly reduce the computational complexity of the SEP of general-Order rectangular QAM.
Joakim Jalden - One of the best experts on this subject based on the ideXlab platform.
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on the Diversity Order of vector perturbation precoding with imperfect channel state information
International Workshop on Signal Processing Advances in Wireless Communications, 2008Co-Authors: Joakim Jalden, J. Maurer, Gerald MatzAbstract:We consider vector perturbation precoding over a quasi-static MIMO channel under the assumption of imperfect channel state information (CSI). This is accomplished via a high SNR analysis, specifically targeting the overall system Diversity Order and the identification of typical errors. The effects of long-term and short-term power constraints, or power allocation policies, are investigated. Our results indicate that under realistic assumptions regarding the channel estimation error the system is mainly interference limited and as such, the particular power constraint does not significantly affect the asymptotic behavior of the error probability. This is in sharp contrast to the case of perfect CSI.
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ON THE Diversity Order OF VECTORPERTURBATIONPRECODINGWITH IMPERFECT CHANNEL STATE INFORMATION
2008Co-Authors: Joakim Jalden, J. MaurerAbstract:We consider vector perturbation precoding over a quasi-static MIMO channel under the assumption of imperfect channel state information (CSI). This is accomplished via a high SNR analysis, specifically targeting the overall system Diversity Order and the identification of typical errors. The effects of long-term and short-term power con straints, or power allocation policies, are investigated. Our results in dicate that under realistic assumptions regarding the channel estima tion error the system is mainly interference limited and as such, the particular power constraint does not significantly affect the asymp totic behavior of the error probability. This is in sharp contrast to the case of perfect CSI.
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The Diversity Order of the Semidefinite Relaxation Detector
IEEE Transactions on Information Theory, 2008Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:In this paper, we consider the detection of binary (antipodal) signals transmitted in a spatially multiplexed fashion over a fading multiple-input-multiple-output (MIMO) channel and where the detection is done by means of semidefinite relaxation (SDR). The SDR detector is an attractive alternative to maximum-likelihood (ML) detection since the complexity is polynomial rather than exponential. Assuming that the channel matrix is drawn with independent identically distributed (i.i.d.) real-valued Gaussian entries, we study the receiver Diversity and prove that the SDR detector achieves the maximum possible Diversity. Thus, the error probability of the receiver tends to zero at the same rate as the optimal ML receiver in the high signal-to-noise ratio (SNR) limit. This significantly strengthens previous performance guarantees available for the semidefinite relaxation detector. Additionally, it proves that full Diversity detection is also possible in certain scenarios when using a noncombinatorial receiver structure.
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On the Maximal Diversity Order of Spatial Multiplexing with Transmit Antenna Selection
arXiv: Information Theory, 2007Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:Zhang et. al. recently derived upper and lower bounds on the achievable Diversity of an N_R x N_T i.i.d. Rayleigh fading multiple antenna system using transmit antenna selection, spatial multiplexing and a linear receiver structure. For the case of L = 2 transmitting (out of N_T available) antennas the bounds are tight and therefore specify the maximal Diversity Order. For the general case with L
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on the maximal Diversity Order of spatial multiplexing with transmit antenna selection
arXiv: Information Theory, 2007Co-Authors: Joakim Jalden, Bjorn OtterstenAbstract:Zhang et. al. recently derived upper and lower bounds on the achievable Diversity of an N_R x N_T i.i.d. Rayleigh fading multiple antenna system using transmit antenna selection, spatial multiplexing and a linear receiver structure. For the case of L = 2 transmitting (out of N_T available) antennas the bounds are tight and therefore specify the maximal Diversity Order. For the general case with L <= min(N_R,N_T) transmitting antennas it was conjectured that the maximal Diversity is (N_T-L+1)(N_R-L+1) which coincides with the lower bound. Herein, we prove this conjecture for the zero forcing and zero forcing decision feedback (with optimal detection Ordering) receiver structures.
Aria Nosratinia - One of the best experts on this subject based on the ideXlab platform.
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Diversity Order in ISI channels with single-carrier frequency-domain equalizers
IEEE Transactions on Wireless Communications, 2010Co-Authors: Ali Tajer, Aria NosratiniaAbstract:This paper analyzes the Diversity gain achieved by single-carrier frequency-domain equalizers (SC-FDE) in frequency selective channels, and uncovers the interplay between Diversity gain d, channel memory length ?, transmission block length L, and the spectral efficiency R. We specifically show that for the class of minimum mean-square error (MMSE) SCFDE receivers, for rates R ? log L/? full Diversity of d = ?+ 1 is achievable, while for higher rates the Diversity is given by d = [2-R L + 1. In other words, the achievable Diversity gain depends not only on the channel memory length, but also on the desired spectral efficiency and the transmission block length. A similar analysis reveals that for zero forcing SC-FDE, the Diversity Order is always one irrespective of channel memory length and spectral efficiency. These results are supported by simulations.
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Diversity Order in ISI Channels with Single-Carrier Frequency-Domain Equalizers
arXiv: Information Theory, 2009Co-Authors: Ali Tajer, Aria NosratiniaAbstract:This paper analyzes the Diversity gain achieved by single-carrier frequency-domain equalizer (SC-FDE) in frequency selective channels, and uncovers the interplay between Diversity gain $d$, channel memory length $\nu$, transmission block length $L$, and the spectral efficiency $R$. We specifically show that for the class of minimum means-square error (MMSE) SC-FDE receivers, for rates $R\leq\log\frac{L}{\nu}$ full Diversity of $d=\nu+1$ is achievable, while for higher rates the Diversity is given by $d=\lfloor2^{-R}L\rfloor+1$. In other words, the achievable Diversity gain depends not only on the channel memory length, but also on the desired spectral efficiency and the transmission block length. A similar analysis reveals that for zero forcing SC-FDE, the Diversity Order is always one irrespective of channel memory length and spectral efficiency. These results are supported by simulations.
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Diversity Order of mmse single carrier frequency domain linear equalization
Global Communications Conference, 2007Co-Authors: Ali Tajer, Aria NosratiniaAbstract:In this paper we investigate the Diversity Order of single-carrier frequency domain equalizers (SC-FDE). Specifically, we look at minimum mean square error (MMSE) linear equalizers utilizing block-transmission and cyclic prefix. It is shown that the Diversity Order in these systems depends on data transmission rate, channel memory length, as well as transmission block length. Analyses reveal that with memory length v and transmission block length L, for the rates Rleslog L/v full Diversity of v+1 is achievable. For higher rates the achievable Diversity Order is degraded and is equal to [2-R L]+1. Therefore MMSE SC-FDE has a Diversity that varies between 1 and v+1, and achieves full Diversity only for a limited range of data rates.
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GLOBECOM - Diversity Order of MMSE Single-Carrier Frequency Domain Linear Equalization
IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference, 2007Co-Authors: Ali Tajer, Aria NosratiniaAbstract:In this paper we investigate the Diversity Order of single-carrier frequency domain equalizers (SC-FDE). Specifically, we look at minimum mean square error (MMSE) linear equalizers utilizing block-transmission and cyclic prefix. It is shown that the Diversity Order in these systems depends on data transmission rate, channel memory length, as well as transmission block length. Analyses reveal that with memory length v and transmission block length L, for the rates Rleslog L/v full Diversity of v+1 is achievable. For higher rates the achievable Diversity Order is degraded and is equal to [2-R L]+1. Therefore MMSE SC-FDE has a Diversity that varies between 1 and v+1, and achieves full Diversity only for a limited range of data rates.
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Outage probability and Diversity Order of linear equalizers in frequency-selective fading channels
Conference Record of the Thirty-Eighth Asilomar Conference on Signals Systems and Computers 2004., 1Co-Authors: Ahmadreza Hedayat, Aria Nosratinia, Naofal Al-dhahirAbstract:We investigate the performance of finite-length linear equalizers through calculation of Diversity Order. We focus on block transmission with cyclic prefix. We prove that, regardless of the channel memory the Diversity Order of zero-forcing equalizer is one. Through asymptotic outage probability analysis, we observe that the minimum mean square equalizer has a varying Diversity Order depending on the spectral efficiency.
Robert W Heath - One of the best experts on this subject based on the ideXlab platform.
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information outage probability and Diversity Order of alamouti transmit Diversity in time selective fading channels
IEEE Transactions on Vehicular Technology, 2008Co-Authors: Robert W Heath, E J PowersAbstract:We analyze the effect of time-selective fading on the information outage probability and Diversity Order of Alamouti transmit Diversity with joint maximum likelihood, symbolwise linear maximum likelihood, zero forcing, and decision feedback detectors. In contrast to the existing bit error rate (BER) and bit error outage (BEO) analyses, we evaluate the information outage probabilities and corresponding asymptotic Diversity Orders for each detector. From the theoretical and simulation results, we demonstrate that, when the channel is time selective, the asymptotic Diversity Orders for the four detectors approach two, zero, one, and one, respectively.
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coordinate interleaved orthogonal design with two transmit antennas in spatially correlated rayleigh fading channels symbol error rate and Diversity Order
IEICE Transactions on Communications, 2007Co-Authors: Robert W Heath, E J PowersAbstract:Full-Diversity transmission for space-time block codes (STBCs) with multiple transmit antennas can be achieved by using coordinate interleaved orthogonal designs (CIODs). To effectively evaluate the performance of CIODs, we derive union upper and lower bounds on the symbol-error rate (SER) and a corresponding asymptotic Diversity Order of symmetric structured CIOD, in particular, with two transmit antennas over quasi-static spatially uncorrelated/correlated frequency-nonselective Rayleigh fading channels. Some numerical results are provided to verify our analysis.
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necessary and sufficient conditions for full Diversity Order in correlated rayleigh fading beamforming and combining systems
IEEE Transactions on Wireless Communications, 2005Co-Authors: David J Love, Robert W HeathAbstract:Transmit beamforming and receive combining are low complexity, linear techniques that make use of the spatial Diversity advantage provided by transmitters and/or receivers employing multiple antennas. There has been a growing interest in designing beamforming schemes for frequency division duplexing systems that use a limited amount of feedback from the receiver to the transmitter. This limited feedback conveys a beamforming vector chosen from a finite set known to both the transmitter and receiver. These techniques often use a set of beamforming vectors where the probability of error expression can not be easily formulated or bounded. It is of utmost importance to guarantee that the sets of beamforming and combining vectors are chosen such that full Diversity Order is achieved. For this reason, necessary and sufficient conditions on the sets of possible beamformers and combiners are derived that guarantee full Diversity Order in correlated Rayleigh fading.
