认知无线电网络的检查协作频谱感知技术

Censor-based cooperative spectrum sensing in cognitive radio networks

在认知无线电中,协作频谱感知通常被用来提高感知性能。但当用户个数较多时,控制信道带宽的限制和感知时延会影响协作感知的性能。作者提出采用检查协作频谱感知可以有效避免这些问题。检查协作频谱感知通过减少认知用户上报基站的感知信息,降低通信负荷和感知时延,从而提高系统的敏感性。通过最大化频谱利用率可以得到最优的不发送概率,从而在感知时延和接入频谱机会的错失上得到折衷。通过分析及仿真结果可以看出,检查协作感知与传统协作感知相比,有效提高了系统的敏感性。通过最优的不发送概率可以确定最佳的感知门限进行感知。

In cognitive radio network,the limit of control channel bandwidth and the sensing delay will more impact the sensing performance of cooperative spectrum sensing when the number of cognitive users becomes very large.Censor-based cooperative sensing was presented to solve this problem.By reducing the number of users sending their local sensing decisions to the base-station,the communication overhead and total sensing delay are decreased.The optimal no decision probability can be achieved by maximizing the spectrum efficiency,which is a metric to compromise sensing overhead and spectrum utilization.According to the analysis and simulation results,the adoption of censored decision can improve the agility of the system.Appropriate sensing thresholds can be achieved by optimal no decision probability to perform censor-based cooperative sensing.