Cooperative spectrum sensing algorithm based on Dempster-Shafer theory

In cognitive radio systems, unlicensed users can use the frequency bands when the licensed users are not present. Hence reliable detection of available spectrum is the foundation of cognitive radio technology. In order to efficiently detect the licensed users under prior knowledge constraints in the fusion center, a novel cooperative spectrum sensing algorithm based on Dempster-Shafer theory is proposed. In this novel algorithm, the credibility and uncertainty are calculated based on the local sensing result of cognitive radios, then fused at the fusion center using Dempster-Shafer theory. The simulation results show that the performance of the novel algorithm is better than energy fusion method. If unlicensed users know more prior knowledge, the performance of the novel algorithm is the same as the optimal linear cooperative spectrum sensing algorithm.