Opportunistic Spectrum Access in Multiple-Primary-User Environments Under the Packet Collision Constraint
Cognitive Radio (CR) technology has great potential to alleviate spectrum scarcity in wireless communications. It allows Secondary Users (SUs) to opportunistically access spectrum licensed by Primary Users (PUs) while protecting PU activity. The protection of the PUs is central to the adoption of this technology since no PU would accommodate SU access to its own detriment. In this paper, the authors consider an SU that must protect multiple PUs simultaneously. They focus on the PU packet collision probability as the protection metric. The PUs is unslotted and may have different idle/busy time distributions and protection requirements.