Full-Duplex SWIPT Relaying Based on Spatial-Modulation

In this paper, we investigate the application of spatial-modulation (SM) in multi-antenna full-duplex (FD) decode-and-forward (DF) relay networks with simultaneous wireless information and power transfer (SWIPT). Both the time switching (TS) and power splitting (PS) protocols are employed. In the proposed scheme, a subset of relay antennas are selected to forward the received information signal with the harvested energy and the remaining inactive antennas receive the energy signal/information signal from the source node. The application of SM at the relay node leads to the throughput improvement of the relay-to-destination link because of the additional information mapped to the active antenna indices, which consequently leads to the overall system throughput improvement. According to the proposed tight SM mutual information (MI) upper bound, we provide a theoretical solution for the system throughput optimization. Monte-Carlo simulations verify the significant throughput gain facilitated by SM as well as the validity of the throughput optimization.