Exact Outage Probability of Relay Selection in Decode-and-Forward Based Cooperative Multicast Systems

In this letter, we present the outage performance of decode-and-forward based cooperative multicast systems with the best relay selection (CM-RS) over Rayleigh fading channels. Especially, we provide an exact and closed-form expression for the outage probability of CM-RS and its diversity order. Through numerical results, the analysis is verified, and the outage performance of CM-RS is compared with that of a single-hop multicast system.