Energy-based cooperative spectrum sensing for emergency communications over fading channels in Cognitive Radio public safety networks

From the perspective of interoperability, Cognitive Radio (CR) is widely studied as an emerging alternative for public safety communications. Spectrum sensing is one of key functionalities enabling the opportunistic spectrum utilization for CR systems. The energy-based cooperative spectrum sensing is mostly adopted in current CR prototype systems due to the low complexity and high detection speed. The cooperative spectrum sensing performance is influenced by the number of collaborative CRs. However, the number of CRs is dynamically changing due to the dynamic behavior of public safety personnel. We study the dynamic behavior of CRs and also derive the exact analytical closed-form expressions for the sensing performance. These expressions lay the framework for utilizing the optimization tools to efficiently guarantee the global optimality for the system parameter design.