Transmit Antenna Selection for Precoding-Aided Spatial Modulation

Abstract

This paper examines the impacts of transmit antenna subset (TAS) selection on the biterror-rate (BER) performance of linear precoding-aided spatial modulation (PSM) multiple-input multipleoutput (MIMO) systems. It is analytically shown that decreasing the number of active transmit antennas by TAS selection, which can be used to reduce the number of RF units at the transmitter side, always degrades the BER performance. The expression of a received signal-to-noise ratio (SNR) loss is also derived and its analytical results are shown to be well-matched with simulation results. Furthermore, it is analyzed that when there are N T transmit antennas, N S selected transmit antennas, and N R receive antennas, an achievable diversity order of the zero-forcing (ZF)-based PSM MIMO systems either with optimal TAS selection or without TAS selection can be given as N T −N R +1. To select an optimal TAS based on exhaustive search, an optimization criterion to maximize the received SNR of the selected TAS is employed. In addition, a low-complexity TAS selection scheme is presented using a decremental strategy. It is also observed that the decremental TAS selection algorithm can achieve almost the same BER and achievable rate performance as the optimal one while attaining much lower complexity. Finally, simulation results show that under the identical number of active transmit antennas, the ZF-PSM MIMO system with TAS selection outperforms the conventional ZF-PSM without TAS selection.INDEX TERMS Transmit antenna selection, multiple input multiple output (MIMO), precoding, zeroforcing (ZF), spatial modulation (SM).

Decoupled Transmit and Receive Antenna Selection for Precoding-Aided Spatial Modulation

“…The ZF and minimum mean square error precoding methods are commonly used in PSM. To be consistent with the previous works for the PSM systems [7], [8], [10], [11] and [18], we utilize the ZF precoding scheme in this paper. Then the ZF precoding matrix is given as  .…”

“…RAS selection has been studied for the PSM systems [21]- [23]. In [18], the effects of only TAS selection on the bit error rate (BER) performance of the zero-forcing (ZF)-based PSM systems have been investigated. In [20], two TAS selection schemes with lowcomplexity have been developed for the PSM systems.…”

“…It should be pointed out that the decremental and incremental TAS algorithms proposed in [18] and [20] are employed for the second step (i.e., TAS selection) in the decoupled TRAS selection scheme of this work. Note that [18] and [20] consider only TAS selection. By contrast, this work proposes an optimal joint TRAS selection scheme for the PSM systems as we have said above.…”

“…It is pointed out that the computational complexity of ( 5) to find an optimal TRAS is very high owing to an exhaustive search when the numbers of transmit antennas and receive antennas are large. To evaluate its computational complexity, we take account of the number of real multiplications (RMs) and the number of real summations (RSs) [18]- [22], [36]. The complexity of the exhaustive search-based optimal TRAS selection algorithm in terms of RMs and RSs, respectively, can be analyzed as…”

Comments and Corrections Correction to “Transmit Antenna Selection for Precoding-Aided Spatial Modulation”

“…In the above article [1], the authors found some mistakes in real summation (RS) computations. As the computational complexity in terms of real summation (RS) is re-evaluated in the revision process, we didn't consider 2 RSs additionally required for a complex multiplication.…”