Super-orthogonal differential space-time trellis coding and decoding

In this paper, a differential space-time trellis-coded scheme based on super-orthogonal space-time trellis codes (SOSTTCs) is proposed. It achieves full diversity and provides an improved coding gain. Based on the per-survivor processing (PSP) technique, a low-complexity suboptimal differential decoder is developed. In slow fading channels, it can approach the performance of SOSTTC with coherent decoding. Furthermore, in time-varying channels, a bank of recursive least square (RLS) type channel predictors are incorporated into the Viterbi decoder to track the channel variance and the RLS predictors do not need training data and channel statistics. The performance analysis is given. Simulation results are presented to illustrate our analytical results and they show that our scheme can achieve a good performance in both slow fading and time-varying fading channels with modest complexity.