Link Adaption aided Enhanced Spatial Modulation for MIMO Transmissions

In this paper, we investigate the benefits of the link adaptation (LA) techniques for enhanced spatial modulation (ESM) based multiple-input multiple-output (MIMO) systems. To be specific, we first apply the power allocation (PA) technique to ESM and propose a novel PA algorithm, namely approximated maximum minimum distance (AMMD)-based PA, in order to improve the bit error rate (BER) performance. Then, we combine transmit antenna selection (TAS) technique and ESM scheme to overcome the constraint that the number of transmit antennas in ESM has to be a power of two as well as to enhance its BER performance by using the space resource. Finally, to seek higher BER performance gain, we consider the joint application of PA and TAS in ESM-MIMO systems. Our simulation results show that the proposed PA-ESM, TAS-ESM and joint PA and TAS aided ESM schemes provide beneficial system performance improvements compared to the conventional ESM scheme.