Abstract: To improve the reliability of spectrum sensing and reduce the burden of the cognitive radio network and the fusion center, a cooperative spectrum sensing algorithm based on double threshold and D-S theory is proposed. This algorithm combines double threshold energy detection with Dempster-Shafer（D-S） theory. By using the double threshold energy detection, some CR users only need to send the local decision data to the FC, and thus the data transmission is reduced. In addition, when the calculation results locate between the two thresholds, it will calculate the trust function by D-S theory and send them to FC. That will reduce the burden and the computation of the FC. Theoretical analysis and simulation results show that the probability of detection of the proposed algorithm is 30% larger than other algorithms, and the performance of its Receiver Operating Curve（ROC） increases 3%.

Key words: cognitive radio, cooperative spectrum sensing, double threshold, Dempster-Shafer（D-S） theory

摘要： 从提高合作频谱感知结果的可靠性以及减小网络开销和融合中心计算负担的角度出发，提出了一种新的基于双门限和证据理论的合作频谱感知算法。该算法在进行本地感知的时候，认知用户通过双门限能量检测直接得到本地判决结果，将认知用户感知到的能量值在两个门限之间的未能进行本地判决的结果的信任度函数发送给融合中心，这样大大减少了融合中心利用证据理论进行软融合的计算量以及传输感知结果带来的网络开销。理论分析和仿真表明，提出算法的检测概率比其他检测算法的检测概率性能提升30%，其接收机操作性能曲线（ROC）性能比性能较好的D-S证据理论提升3%。

关键词: 认知无线电, 合作频谱感知, 双门限, 证据理论