Power allocation algorithms in parallel relay communication networks

We consider a parallel relay communication network based on the nonorthorgonal amplify-and-forward protocol. We design two optimal power allocation schemes: separate power allocation (SPA) of the relays using the improved water-filling algorithm and joint power allocation (JPA) of the source and relays using convex optimization algorithm. Simulation results show that, in the fading channels with path loss, the proposed JPA and SPA have better mutual information performances than equal power allocation and direct transmission without relay.