Bayesian Approach for Spectrum Sensing in Cognitive Radio

Unused portions of allocated fixed spectrum are called spectrum holes or white spaces. These spectrum holes or white spaces are used by cognitive radio technology in an opportunistic manner. It will solve the global problem of spectrum scarcity. Cognitive radio assigns spectrum or radio resources in a manner to keep interference between CR devices and licensed users within limit. The scope of this paper is to achieve higher spectrum utilization in cognitive radio networks, using an optimal Bayesian Detector. If the primary user is highly inactive and the primary signals are digitally modulated, we will derive the optimal detector structure. And further suboptimal detectors in low and high SNR scenario. The Bayesian Detector has better performance than the Energy Detector in high signal to noise ratio and same performance as ED in low SNR for spectrum utilization. We provide Detection probability and false alarm probability analysis.