Throughput performance optimization in cognitive radio networks under Rayleigh fading

We consider a time slotted cognitive radio (CR) network under Rayleigh fading where multiple secondary users (SUs) contend for spectrum usage over available primary users´ channels. In the contention, all SUs use common access probabilities to decide whether they access one of available channels. We focus on the throughput performance of an arbitrary SU. To improve the throughput performance of SUs, it is desirable that the access probabilities are adapted to the information on channel status and fading condition. In the analysis, we derive the optimal access probabilities that maximize the throughput performance of an arbitrary SU. From our analysis, we provide an insight on how to obtain optimal access probabilities in the CR network. We also investigate the effect of the knowledge of channel status and fading condition on throughput performance. Numerical results are provided to investigate throughput performance behavior.