Performance analysis of MIMO-OSTBC based selective DF cooperative wireless system with node mobility and channel estimation errors

This paper analyzes the end-to-end performance of a selective Decode-and-Forward (DF) based MIMO-OSTBC cooperative wireless system over time-varying Rayleigh fading links. Closed form expressions are derived for the per-frame average pair-wise error probability (PEP) and SNR outage probability considering a realistic scenario where all the communicating nodes including the relay are in motion along with channel estimation errors at each receiving node. Further, we present a framework for optimal power allocation at the source and relay nodes. Simulation results are presented to demonstrate the outage and PEP performance of the MIMO-OSTBC DF cooperative relaying system and verify the analytical expressions derived. It is observed that the optimal power factors, obtained by considering the scenario with perfect channel estimates and static nodes, leads to a lower outage and PEP performance in the low as well as moderate SNR regimes. Moreover, at high SNR, the outage performance for both equal and optimal power allocation approaches the derived asymptotic floor.