Low-Complexity Improved-Rate Generalised Spatial Modulation: Bit-to-Symbol Mapping, Detection and Performance Analysis

Abstract

Low-complexity improved-rate generalised spatial modulation (LCIR-GSM) is proposed to mitigate the high complexity of the mapping book design and demodulation of variable-<inline-formula><tex-math notation="LaTeX">${N_a}$</tex-math></inline-formula> GSM. Specifically, <i>first of all</i>, we propose two efficient schemes for mapping the information bits to the transmit antenna activation patterns, which can be readily scaled to massive MIMO setups. <i>Secondly</i>, we derive a pair of low-complexity near-optimal detectors, one of which has a reduced search scope, while the other benefits from a decoupled single-stream based signal detection algorithm. <i>Finally</i>, the performance of the proposed LCIR-GSM system is characterised by the improved error probability upper bound. Our simulation results confirm the improved error performance of our proposed scheme, despite its reduced signal detection complexity.