Abstract
Cognitive Radio (CR) is widely studied as an emerging alternative for public safety communications from the aspect of opportunistic spectrum usage for interoperability, which is hampered by incompatible radio equipments and different operational radio frequency bands. Spectrum sensing is one of the key functionalities in Cognitive Radio Networks. Spatially distributed cooperative spectrum sensing can effectively solve the hidden primary user problem. However, the number of CRs in the cooperation is dynamically changing over the time at emergencies. We model the emergent behaviors of CRs and derive the dynamic probability of detection and probability of false alarm in the energy-based cooperative spectrum sensing for public safety cognitive radio networks over composite shadowing/fading channels.