基于动态双门限和D-S证据理论的合作频谱感知算法

针对传统能量检测算法门限设置单一且不适应感知信道环境差异的问题,为了提高合作频谱感知结果的可靠性,减小网络开销和融合中心计算的负担,提出了将动态双门限能量检测和D-S证据理论相结合的合作频谱感知算法.在进行本地感知时,该算法可以让认知用户通过双门限能量检测方法直接得到本地判决结果,同时根据信道环境的变化自适应调整双门限值,并在双门限内使用D-S证据理论,感知双门限内未判决结果的信任度函数,将其发往融合中心,这样可以减少融合中心的计算量以及传输带来的网络开销.仿真结果表明,双门限D-S证据理论的融合结果要优于D-S证据理论和OR准则.

Cooperative Sensing Algorithm Based on Dynamic Double Threshold and D-S Evidence Theory

Considering energy detection algorithm’s shortages and the difference of channel, a cooperative sensing algorithm based on dynamic double threshold and D-S theory is proposed to improve the reliability of spectrum sensing and reduce the burden of the cognitive radio network and the fusion center. This algorithm combines double threshold energy detection with D-S evidence theory. By using the double threshold energy detection, some CR users obtain the local decision directly. At the same time, the two thresholds can be adjusted adaptively according to the status of channels. D-S evidence theory is used in two thresholds that CR users need to send the local decision data to the FC and thus reduce the data transmission. Theoretical analysis and simulation results show that fusion of double threshold and D-S evidence theory is better than D-S evidence theory and OR criterion.