Differential detection for two-user cooperative diversity systems

In this paper, a two-user cooperative diversity scheme with high rate and low decoding complexity is proposed where the cooperation is performed suitably to Alamouti's space-time block coding technique. The scheme does not require coding or differential modulation and the data bits are directly transmitted by MPSK modulation. The transmitted symbols are detected at the destination without any requirement of the state information of the channels between users and destination. The error performance of the proposed system is evaluated by computer simulations for BPSK modulation in quasi-static Rayleigh fading channel and the results are compared to the corresponding reference systems.