Cooperative Spectrum Sensing in Multiuser Cognitive Radio Networks with Best Relay Selection

We propose a cooperative spectrum sensing scheme based on the best relay selection in a multiple-user cognitive radio network,which can improve the system sensing performance by achieving the spatial diversity gain.Closed-form expressions of detection probability for the traditional non-cooperative sensing scheme and the proposed scheme are derived in Rayleigh fading channels to show the effects of multiuser cooperation on the detection performance.Furthermore,we compare the non-cooperative scheme with the multiuser cooperation scheme in terms of detection probability through numerical experimentations.Numerical results illustrate that the detection probability of our scheme is improved greatly compared to traditional non-cooperation and moreover,with the growth of the number of candidate relays,the improvement of detection probability achieved by our scheme is larger.