Outage performance analysis of amplify-and-forward cognitive relay networks with partial relay selection

In this paper, we consider amplify-and-forward cognitive relay networks in a spectrum-sharing environment. We present the performance analysis under two different partial relay selection (PRS) schemes, namely source-relay partial relay selection (SR-PRS) and relay-destination partial relay selection (RD-PRS). Specifically, we consider interference power constraint on secondary source and relay nodes, and transmit power constraint on secondary relay nodes. In this context, the exact outage probability is derived over Rayleigh fading channels. Our results show that the system performance is dominated by the power constraints and the number of secondary relay nodes. Moreover, we provide simulation results to compare the two different PRS schemes. Finally, Monte Carlo simulations are shown to validate the accuracy of the analytical results.