Cooperative Differential Space-Time Transmission Scheme for MIMO Relay Networks

In this paper, we develop a new cooperative differential space-time transmission scheme for multiple-input multiple-output (MIMO) relay networks with partial channel state information (CSI). We propose an adaptive selection amplify-and-forward (AF) protocol which is combined with selection combining and antenna selection. Differential space-time coding is employed at the transmitter when the CSI is imperfect at the receiver. And maximum likelihood differential detection is derived. Simulation results show that the proposed scheme achieves higher diversity gain and better bit-error rate (BER) performance compared with the traditional point-to-point MIMO scheme with the same number of transmit and receive antennas and the equal power efficiency and spectral efficiency.