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1.
The asymptotic bit error performance of the Alamouti scheme with transmit antenna selection is investigated for imperfect selection of antenna subset. It is shown that the transmit diversity order is equal to the largest ordinal number of the antenna within the selected antenna subset. 相似文献
2.
Jinhong Yuan 《Wireless Communications, IEEE Transactions on》2006,5(7):1706-1715
We consider the problem of selecting a subset of transmit antennas in MIMO systems to minimize error probability when only partial channel information is available at the transmitter. An upper bound for error probability of space-time coded transmit antenna selection scheme conditioned on the channel state information is presented. Based on the performance analysis, a criterion of selecting a subset of available transmit antennas to minimize the upper bound on the PEP is proposed. In contrast to other transmit antenna selection schemes for uncoded transmission or with a fixed number of antennas within the selection subset in the literature, the proposed scheme can adaptively select both a variable number of transmit antennas and their corresponding space-time codes for transmission. Furthermore, we present pragmatic space-time trellis coding schemes for slow Rayleigh fading channels. The principal advantage of the schemes is that a single encoder and decoder can be used for systems with a variable number of transmit antennas. The performance of the pragmatic space-time codes with adaptive antenna selection and the effect of the imperfect channel estimation on performance are evaluated by simulations. It is shown that the adaptive selection offers considerable antenna selection gain relative to the antenna selection system with a fixed number of antennas within the selection subset 相似文献
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Van-Bien Pham 《Wireless Personal Communications》2013,71(4):2937-2945
A new transmit antenna selection (TAS) scheme with phase feedback for multiple-input multiple-output systems is proposed in this paper. This scheme allows two or more transmit antennas to simultaneously use one radio frequency chain. By grouping the transmit antennas according to their similarities in instantaneous channel coefficients into two subsets and treating each subset as a single antenna, both hardware complexity reduction and antenna array gain can be achieved. Compared with the transmit antenna selection combined with space-time block code (TAS/STBC) scheme, the proposed TAS scheme provides excellent robustness, in terms of symbol error rate performance, against spatially correlated fading channels. Moreover, the proposed TAS scheme need not use STBC encoder and decoder which used in the TAS/STBC schemes. Therefore, the proposed TAS scheme is simpler than the TAS/STBC schemes in practical hardware implementation. 相似文献
5.
接近最优的编码MIMO系统的发送天线子集选择算法 总被引:1,自引:0,他引:1
多天线无线系统可提供更大的信道容量和更好的抗衰落能力,发送端利用反馈的部分信道状态信息进行发送天线子集选择能够进一步提高信道容量。该文提出了一种MIMO系统的快速的、动态的天线子集选择算法,其提供的信道容量高于已有的静态算法,且接近于最优天线选择算法,而无需计算所有可能的天线子集组合的信道容量,因而具有更低的复杂度。将本文算法与比特交织编码调制(BICM)技术相结合,对各天线速率进行适配,提出了空时自适应比特交织编码调制(ST-ABICM)方案。仿真结果证实了该方案性能的优越性。 相似文献
6.
Spatial multiplexing with transmit antenna and constellation selection for correlated MIMO fading channels 总被引:10,自引:0,他引:10
We consider spatial multiplexing systems in correlated multiple-input multiple-output (MIMO) fading channels with equal power allocated to each transmit antenna. Under this constraint, the number and subset of transmit antennas together with the transmit symbol constellations are determined assuming knowledge of the channel correlation matrices. We first consider a fixed data rate system and vary the number of transmit antennas and constellation such that the minimum margin in the signal-to-noise ratio (SNR) is maximized for linear and Vertical Bell Laboratories Layered Space-Time (V-BLAST) receivers. We also derive transmit antenna and constellation selection criteria for a successive interference cancellation receiver (SCR) with a fixed detection order and a variable number of bits transmitted on each substream. Compared with a system using all available antennas, performance results show significant gains using a subset of transmit antennas, even for independent fading channels. Finally, we select a subset of transmit antennas to maximize data rate given a minimum SNR margin. A lower bound on the maximum outage data rate is derived. The maximum outage data rate of the SCR receiver is seen to be close to the outage channel capacity. 相似文献
7.
When a high spectral efficiency is needed, the cost of Euclidean distance‐based antenna selection for spatial modulation (EDAS‐SM) in terms of hardware, size, and computational complexity is significantly increased because of the large transmit antenna array required. In comparison, generalized spatial modulation (GSM) can match the spectral efficiency of EDAS‐SM, while using significantly fewer transmit antenna elements. However, the error performance of GSM is naturally limited because of the use of a predetermined and fixed set of transmit antenna combinations. By exploiting knowledge of the channel, the optimal set of transmit antenna combinations can be selected by maximizing the minimum Euclidean distance between transmit vectors. In this paper, an adaptive scheme for selection of the optimal set of transmit antenna combinations is proposed to improve the reliability of GSM. The computational overhead of the said scheme is relatively high; hence, a low‐complexity suboptimal scheme for selection of the set of transmit antenna combinations is further proposed. The improved GSM schemes address the spectral efficiency limitation of EDAS‐SM, while demonstrating superior error performance. 相似文献
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Asymptotic performance of transmit antenna selection with maximal-ratio combining for generalized selection criterion 总被引:2,自引:0,他引:2
Zhuo Chen 《Communications Letters, IEEE》2004,8(4):247-249
In this letter, we investigate the asymptotic error performance of an uncoded multiple-input-multiple-output (MIMO) scheme combining transmit antenna selection and receiver maximal-ratio combining (MRC) with a generalized selection criterion. A single transmit antenna corresponding to a fixed ordinal number of order statistic is selected for uncoded transmission. The order statistics consist of instantaneous channel power gain between each transmit and all the receive antennas. A general asymptotic bit error rate (BER) expression is derived for all values of ordinal number. An interesting conclusion is reached that the system diversity order is proportional to the ordinal number of the selected antenna. 相似文献
10.
分布式M IMO天线结构可以降低发射功率,减少小区干扰,而天线选择技术在保持了M IMO系统优点的同时降低成本。TD-SCDMA有独特的时隙结构,可将不同时隙用于不同的天线组来覆盖不同的小区。基于此,提出了一种分布式天线选择的动态小区覆盖技术,采用两级天线选择,第一级可根据用户的具体位置选择天线组并确定覆盖范围,有效减少小区干扰,同时采用了预分配天线组方法,避免了通用天线选择算法的复杂性;第二级在选定的天线组内确定具体的天线,仿真结果说明该方法具有与一般天线选择相同的性能但更简单。 相似文献
11.
In this paper, we consider a transmit antenna and user selection for maximum-likelihood (ML) detector in multiuser spatial multiplexing systems. The conventional algorithm that maximizes the minimum stream SNR is not optimal in terms of the error probability, because it is tailored for linear detectors. We propose a simple transmit antenna and user selection scheme for the ML detector based on maximizing the minimum distance. Numerical results show that the proposed scheme provides enhanced performance compared with the conventional algorithms in terms of the error probability of ML receiver. 相似文献
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空间相关MIMO信道中一种自适应的天线选择算法 总被引:1,自引:0,他引:1
该文研究了空间相关性对于多输入多输出空间复用(MIMO-SM)系统性能影响问题,并提出了一种适用于迭代迫零软干扰抵消接收机的天线选择算法。平坦衰落信道中,发送天线相关性将降低接收天线选择算法的性能,该文所研究的算法采用可变的接收天线数以获得不同的接收分集,增加一定的硬件实现复杂度但可以显著减小发送天线相关性引起的误码性能下降。在2个发送天线,4个接收天线的天线配置场合,计算机仿真证实该算法在帧误码率上优于简单的行相关算法(CBM)。 相似文献
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《Vehicular Technology, IEEE Transactions on》2009,58(3):1281-1291
16.
Analysis of Transmit Antenna Selection/Maximal-Ratio Combining in Rayleigh Fading Channels 总被引:11,自引:0,他引:11
《Vehicular Technology, IEEE Transactions on》2005,54(4):1312-1321
In this paper, we investigate a multiple-input-multiple-output (MIMO) scheme combining transmit antenna selection and receiver maximal-ratio combining (the TAS/MRC scheme). In this scheme, a single transmit antenna, which maximizes the total received signal power at the receiver, is selected for uncoded transmission. The closed-form outage probability of the system with transmit antenna selection is presented. The bit error rate (BER) of the TAS/MRC scheme is derived for binary phase-shift keying (BPSK) in flat Rayleigh fading channels. The BER analysis demonstrates that the TAS/MRC scheme can achieve a full diversity order at high signal-to-noise ratios (SNRs), as if all the transmit antennas were used. The average SNR gain of the TAS/MRC is quantified and compared with those of uncoded receiver MRC and space-time block codes (STBCs). The analytical results are verified by simulation. It is shown that the TAS/MRC scheme outperforms some more complex space-time codes of the same spectral efficiency. The cost of the improved performance is a low-rate feedback channel. We also show that channel estimation errors based on pilot symbols have no impact on the diversity order over quasi-static fading channels. 相似文献
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18.
Transmit antenna selection in spatially multiplexed multiple-input multiple-output (MIMO) systems is a low complexity low-rate
feedback technique, which involves transmission of a reduced number of streams from the maximum possible to improve the error
rate performance of linear receivers. It has been shown to be effective in enhancing the performance of single-user interference-free
point-to-point MIMO systems. However, performance of transmit antenna selection techniques in interference-limited environments
and over frequency selective channels is less well understood. In this paper, we investigate the performance of transmit antenna
selection in spatially multiplexed MIMO systems in the presence of co-channel interference. We propose a transmission technique
for the downlink of a cellular MIMO system that employs transmit antenna selection to minimize the effect of co-channel interference
from surrounding cells. Several transmit antenna selection algorithms are proposed and their performance is evaluated in both
frequency flat and frequency selective channels. Various antenna selection algorithms proposed in the literature for single
user MIMO links are extended to a cellular scenario, where each user experiences co-channel interference from the other cells
(intercell interference) in the system. For frequency selective channels, we consider orthogonal frequency division multiplexing
(OFDM) with MIMO. We propose a selection algorithm that maximizes the average output SINR over all subcarriers. A method to
quantify selection gain in frequency selective channel is discussed. The effect of delay spread on the selection gain is studied
by simulating practical fading environments with different delay spreads. The effect of the variable signal constellation
sizes and the number of transmitted streams on the bit error rate (BER) performance of the proposed system is also investigated
in conjunction with the transmit antenna selection. Simulation results show that for low to moderate interference power, significant
improvement in the system performance is achievable with the use of transmit antenna selection algorithms. Even though the
gain due to selection in frequency selective channels is reduced compared to that in flat fading channels due to the inherent
frequency diversity, the performance improvement is significant when the system is interference limited. The performance improvement
due to reduced number of transmit streams at larger signal constellation sizes is found to be more significant in spatially
correlated scenarios, and the gain due to selection is found to be reduced with the increased delay spread. It is found that
employing transmit antenna selection algorithms in conjunction with adaptation of the number of transmitted streams and the
signal constellation sizes can significantly improve the performance of MIMO systems with co-channel interference. 相似文献
19.
Liang Yang 《Wireless Personal Communications》2010,55(2):225-235
In this paper, we present a comprehensive performance analysis of multiple-input multiple-output (MIMO) systems with transmit
antenna selection (TAS) and stochastic power allocation (SPA) for the spatially correlated fading channels. Two best transmit
antennas that maximize the instantaneous received signal-to-noise (SNR) are selected to transmit the Alamouti scheme and maximal-ratio
combining (MRC) is applied at the receiver. With correlation matrices available to the transmitter, SPA is applied on these
selected antennas. Two different methods are given to derive the explicit upper bounds on the bit-error rate (BER) performance.
Finally we present numerical results to verify our analysis. It is shown that the TAS/SPA scheme can achieve high performance
in spatially correlated channels. 相似文献
20.
Seijoon Shim Kyeongyeon Kim Chungyong Lee 《Communications Letters, IEEE》2005,9(2):124-126
A new antenna shuffling scheme for DSTTD (double space time transmit diversity) is proposed. The proposed method obtains the shuffling pattern directly from the estimated channel by maximizing minimum post-processing SNR (signal to noise ratio), while the conventional method minimizes channel correlation. Since the minimum post-processing SNR is directly related with error performance, the proposed method shows better bit error rate performance than the conventional method. 相似文献