Cooperative cognitive radios with optimal primary detection and packet acceptance control

In this paper, we investigate the stable throughput of a cognitive interference channel (four nodes: a primary transmitter- receiver pair and a secondary transmitter-receiver pair) with random packet arrivals and possible relaying of primary packets by the secondary transmitter. We extend the previous work [1] by considering the optimal design of the secondary transmitter with the following additional degrees of freedom: a) optimization of the detector of the primary activity (trade-off between probability of false alarm and probability of missed detection); b) a packet acceptance control mechanism that prevents queue overflow due to the traffic relayed on behalf of the primary. Moreover, we investigate the impact of errors in detecting the primary activity on the queuing delays.