On Throughput Analysis for Cognitive Interference Relay Channel

We consider a two-user Gaussian interference channel with a relay. Two source-destination pairs and the relay share a single common channel, and the relay assists both sources in communicating the messages to their respective destinations. We mainly focus on the "amplify-and-forward" (AF) relaying strategy, and derive upper bound and lower bound on achievable sum rate accordingly. Next, we consider the application of the above model in cognitive radio (CR) networks. We assume one of the source-destination pair is a cognitive user (CU), and the other is a primary user (PU). We propose schemes that can ensure the coexistence between CU and PU, in the sense that there is no rate degradation for PU due to sharing of the channel. Further, we investigate the throughput of CU in different communication scenarios.