Cooperative Spectrum Sensing with Double Threshold Detection Based on Reputation in Cognitive Radio

Cooperative spectrum sensing can mitigate the effects of shadowing and fading. However, when the number of cognitive users is very large, the bandwidth for reporting their sensing results will be insufficient. In order to eliminate the fail sensing problem for a cognitive radio system with double threshold detector, a new cooperative spectrum sensing algorithm is presented based on reputation in this paper. In particular, the closed forms for the normalized average number of sensing bits, the probabilities of the detection and the false-alarm are derived. Simulation results show that the average number of sensing bits decreases greatly without failing sensing, and the sensing performance is improved comparing with the conventional double threshold detection and the conventional single threshold detection.