Receive diversity in cognitive relay transmission: Outage analysis

Abstract—This paper analyses outage probability of cognitive relay transmissions using maximal ratio combining (MRC) technique at relay and destination nodes. In the cognitive system, an exact outage probability in the secondary relay network is formulated in the absence of perfect channel state information (CSI) of interference links between primary and secondary networks. The analytical results and related simulation ones show that an increase in interference power (from the primary network) reduces diversity gains in the secondary network.