Performance analysis of decode-and-forward MIMO relay networks with keyhole and Nakagami-m fading effects

In this paper, we analyze the performance of decode-and-forward (DF) multiple-input multiple-output (MIMO) relay networks in which the source and relay use the same orthogonal space-time block code (OSTBC) for transmission whereas the relay and destination use maximum — ratio-combining (MRC) for reception. In particular, by assuming that the DF relay operates over Nakagami-m fading channels in the presence of the keyhole, we derive the exact closed-form expressions of the outage probability (OP) and the symbol error probability (SEP) for MPSK modulation which enables us to analyze the performance of the considered system. Simulation results are presented to verify the theoretical analysis and show excellent agreement.