Decision-feedback multiple-symbol differential detection of differential space-time modulation in continuously fading channels
Linear prediction (LP)-based decision-feedback differential detection (DFDD) only works for diagonal differential space-time modulation (DSTM) when fading is changing fast and continuously. For other constellations, it suffers bad performance. We propose DFDD based on multiple-symbol differential detection (MSDD) for DSTM to cope with continuous fading. A key observation is that the correlation matrix of the received signal can be expressed in terms of DSTM matrices corresponding to the sent information symbols. In this way, decision feedback can be inserted into the MSDD metric, yielding a DF-MSDD receiver while maintaining almost the same performance as MSDD.