Multiple-symbol differential detection for cooperative system

Distributed space-time coding is a cooperative transmission scheme proposed for wireless relay networks. With this scheme, the performance of wireless communication can be greatly improved and the transmit rate can be perfectly accelerated. In this paper, using the maximum likelihood principle, we propose a multiple-symbol differential detection (MSDD) scheme, which reduces the 3dB gap between single-symbol differential detection and multiple-symbol detection. In MSDD for cooperative system over Rayleigh fading channels without channel state information, blocks of N received symbols are jointly processed to decide on N-1 data symbols. The simulation results show that our proposed MSDD is 1.5 dB better than single-symbol detection, at high SNR.