Outage Performance of DF-Based Cooperative Multicast in Spectrum-Sharing Cognitive Relay Networks

This letter investigates the outage performance of decode-and-forward-based cooperative multicast (CM) in spectrum-sharing cognitive relay networks (CRNs). Considering a CRN coexisted with multiple primary users, a closed-form expression for the exact outage probability of CM is derived over independently and non-identically distributed Rayleigh fading channels. The asymptotic analysis is also presented to reveal that the diversity gain of CM in CRNs is determined by the number of relays, and the spectrum-sharing scenario only has impact on coding gain. Simulation results corroborate our theoretical analysis.