认知无线传感网可以合理利用空闲的授权频段来克服传统无线传感器网络的频谱资源短缺这一瓶颈。认知无线传感网的首要任务是检测授权频段以及对主用户的存在与否进行判断。由于信道衰落，主用户与节点间的感知信道是时变的。文中提出了一种多时隙检测模式，节点独立地在各时隙内检测授权频段的状态并对各时隙的判决结果进行融合并做出判决，簇头接收到簇内各节点传送的判决结果后，对它们进行融合得出判决结果，然后簇头将各自的判决结果传送给融合中心，融合中心进行融合并得出最终判决结果。故需要进行三步融合，这样做的好处是不仅能获得空间分集，还能获得时间分集。而且，对簇的个数和感知时隙的个数进行了优化，使得吞吐量能耗比达到最大值。根据仿真结果，在主用户得到充分保护的前提下，当感知时隙的个数和簇的个数达到最优值时，吞吐量能耗比达到最大值。%Cognitive wireless sensor network can be reasonable use of idle authorized spectrum to overcome the bottleneck of spectrum re-sources shortage in the traditional wireless sensor network. Cognitive wireless sensor network's first priority is to detect authorized spec-trum as well as to judge the existence of the primary user. Due to the channel fading,the perception channel between the primary user and the node is time-varying. Propose a multiple time slots detection model in this paper. The node independently detects the status of author-ized spectrum in each time slot and fuses and judges results of each time slot,the cluster head fuses the results after receiving the judgment transmitted by each node to obtain the judgment results,and then cluster heads will transmit each judgment results to the fusion center,the fusion center gets final judgment result by fusing. Therefore require three steps,the advantage not only can obtain spatial diversity,but al-so can acquire time diversity. And the number of clusters and perception of time slot is optimized,to achieve the maximum of the ratio of throughput to energy consumption. According to the simulation results,on the premise that primary users are fully protected,when the number of perception of time slot and the number of clusters achieve the optimal value,the ratio of throughput to energy consumption a-chieves the maximum.
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