Performance Bounds of Opportunistic Cooperative Communications With CSI-Assisted Amplify-and-Forward Relaying and MRC Reception

Analytically studying the outage performance of channel-state-information (CSI)-assisted amplify-and-forward (AF) cooperative networks with maximal ratio combining (MRC) receivers at the destination has always been a difficult task. In this paper, we will derive upper and lower performance bounds-including outage probability, ergodic achievable rate, and average symbol error rate-for such a network that selects the "best relay" out of multiple relays to carry out the relay transmission. Our results show that the derived analytical bounds are able to accurately predict the simulated performance. The analytical technique used here can further be applied to investigate multiple-relay systems under dissimilar fading channel conditions.