Antenna grouping assisted spatial modulation for massive MIMO systems

Abstract

In this paper, an antenna grouping assisted spatial modulation scheme is proposed for massive MIMO systems. Massive multiple-input-multiple-output (MIMO) systems are capable of offering abundant spatial capacity by deploying hundreds of antennas at the base station (BS). Spatial modulation (SM) is one of the key technologies in exploiting spatial capacity, which maps the information bits to the active antenna patterns. However, the classical SM having only one radio frequency (RF) chain to be active significantly reduces the spatial multiplexing gain offered by massive antennas. Generalised spatial modulation (GSM) is an extension of SM, which allows several antennas to be active. With multiple active antennas, the throughout improves while the bit error ratio (BER) performance becomes poor. Thus, we propose an antenna grouping assisted spatial modulation, which is called as grouping SM (GrSM). Explicitly, the transmitting antennas are partitioned into multiple groups based on their channel characteristics and each group activates a single antenna for delivering signals. Furthermore, the upper bound of the BER of the proposed GrSM is also theoretically analyzed. Simulation results are presented to verify the effectiveness of the proposed GrSM in terms of achievable BER performance with same bit rate in comparison with SM and GSM.