Stability Analysis of a Cognitive Multiple Access Channel With Primary QoS Constraints

In this paper, a cognitive radio scenario composed of one primary (Licensed) node and M secondary (Unlicensed) nodes coexisting in the same spectral resource is considered. According to the commons model of cognitive radio, the secondary nodes are required to guarantee Quality-of-Service (QoS) constraints on the primary activity. Assuming a collision channel model, the stability region of the arrival rates at the secondary queues is investigated for given primary throughput and QoS constraints defined in terms of average delay of primary packets. Inner and outer bounds on the stability region are derived.