Optimal power allocation and best relay positioning in opportunistic incremental amplify-and-forward cooperative system

In this paper, aiming to minimize the system outage probability in the condition of limited total power consumption, we study the optimal power allocation and relay positioning of the opportunistic incremental Amplify-and-Forward (OIAF) cooperative system over Rayleigh fading channels with the utilization of convex optimization theory. The analysis of the outage probability and bit error rate (BER) performance is provided. Moreover, we also provide the analysis about the impact of information rate R on the BER performance under certain conditions when the number of the relays, the relay position and also the total power vary. Simulation results show that the proposed joint power optimization and best relay positioning scheme has advantages over other schemes in outage performance.