Research On Cooperative Spectrum Sensing Algorithm Based On Node Credibility

In the cooperative spectrum sensing of cognitive radio networks, the poor channel environment often results the local spectrum detection performance of the sensing nodes to decline. Sometimes, fault nodes or malicious nodes deliberately send some wrong information to disturb the fusion center to make the global decision. Moreover, large sensing information are transmitted to the fusion center lead to channel overhead and energy consumption all increase, the lifecycle of wireless network is shorted.This paper researches a cooperative spectrum sensing algorithm based on node credibility. In the proposed algorithm, the fusion center weights the local detection result according to each detection node's credibility, the attenuation factor is introduced to update node credibility,minimize the harmful effects of accidental local detection errors.Meanwhile, according to the historical sensing information of sensing nodes group the sensing nodes into reliable nodes, fault or malicious nodes and unreliable nodes, and the fault or malicious nodes are discarded and prevented from the data fusion in fusion center, the current local detection results of the unreliable nodes are not considered in the current global decision. And then, based on the traditional soft decision, add a node selection process by means of credibility accumulation to cut down the number of nodes participating in the data fusion as much as possible, reduce the energy consumption and data transmission.The simulation results show that the proposed algorithm can effectively avoid the interference of fault or malicious nodes, reduce channel overhead, improve the cooperative spectrum sensing performance and prolong the lifecycle of cognitive networks.