认知无线电多簇联合频谱感知算法

Multi-cluster cooperative spectrum sensing in cognitive radio

摘要:

针对衰落信道下,认知无线电的联合频谱感知性能会降低,提出了簇内合作和多簇融合的联合频谱感知算法. 算法中所有认知用户被分成若干个簇,簇内到融合中心最近的用户为簇头用户,簇内其他用户将本地感知信息发送给簇头,并由簇头获得本簇的合作感知结果；然后簇头将感知结果发送给融合中心,融合中心采用"或准则"合并各簇的感知结果并给出对授权用户的最后判决. 仿真表明,当信道完美时,本文算法和未分簇联合感知算法的感知性能一致,当信道衰落严重时,本文算法的性能会有显著提高,并且分的簇越少,算法的性能越高.

Abstract:

Since the performance of cooperative spectrum sensing in cognitive radio (CR) will decrease in the fading channel, a clustering cooperative spectrum sensing algorithm based on the cooperation in cluster and multi-clusters combination is proposed in this paper. In the proposed algorithm, all the CR users are divided into several clusters, and the CR user in each cluster with the shortest distance from the fusion centre is regarded as the cluster head. The cluster head collects the local sensing information from the other CR users in the cluster, obtains the cooperative sensing result of the cluster, and then sends the result to the fusion centre which will combine the results from all the clusters by "OR rule" in order to obtain the final decision on the presence of the primary user. The simulation indicates that when the channels are perfect, the performances of the proposed algorithm and traditional algorithm without clustering are nearly the same, however, when the channels are in deep fading, the performance of the proposed algorithm is improved remarkably, and it can be increased by the decreasing of the number of clusters. 