Multiple-Symbol Differential Sphere Detection for Dual-hop Amplify-and-Forward Relaying Based Differential Spatial Modulation

Abstract

Differential Spatial Modulation (DSM) is a newly MIMO technique, which need no channel state information at the receiver. In this paper, we study the application of DSM in a dual-hop amplify-and forward (AF) relaying system. Owing to the poor performance of conventional differential detection in fast fading channels, we devise a nearly optimal multiple-symbol detector. First, we derive the ML metric, which is not a closed-form expression. Then, a modified suboptimal decision metric is derived instead. Simulation results show that the proposed multiple-symbol detection can effectively improve the performance of DSM in fast-fading channels.