Cooperative spectrum sensing based on spatially-correlated Rayleigh shadowing

Cooperative spectrum sensing has been proposed to help raise the sensitivity requirement under the fading propagation in Cognitive Radio Network. In this paper, we introduce a new explanation that the best probability of detection or false alarm can be achieved from only parts of the cooperative secondary users under different scenarios. Specifically, we analyze from the new perspective of spatially-correlated shadowing and formulate the probability of detection as a function of the correlation coefficient. The simulation shows that, given a targeted cooperative probability of false alarm, the cooperative probability of detection decreases as correlation increases. The range of an appropriate distance between secondary users is derived based on the accuracy and sensitivity of the Cognitive Radio system. According to the correlation coefficient between two SUs, we can determine the cooperative SUs´ set to get better performance of Cognitive Radio Network.