认知无线电协作频谱感知机制的优化

摘要

The objective of spectrum sensing is to provide more spectrum access opportunities to cognitive rafio (CR) users without causing interference to primary users. For the limitation of local spectrum detection, cooperative spectrum sensing is proposed. To maximize the spectrum sensing efficiency of single licensed channel under satisfying interference constraint to primary user, a novel cooperative spectrum sensing scheme is proposed by jointly optimizing the sensing parameters of sensing duration, the transmission duration and the numbers of CR users participating in cooperative spectrum sensing and the optimal solution is obtained based on exhaustive search. Moreover, the sensing efficiency problem is studied in multichannel environment and a licensed channel selective allocation scheme is proposed. Simulation results verify the effectiveness of the proposed method.%频谱感知的目标是在尽量避免对主用户造成干扰的条件下为感知用户提供尽可能多的频谱接入机会.由于单用户频谱检测算法的局限性,协作频谱感知被提了出来.在满足对主用户干扰限度的条件下,为了使单个授权信道的频谱感知效率达到最大,引入一种新的协作频谱感知机制,联合优化包括感知时间、传输时间、参与协作的感知用户数目在内的感知参数,并通过穷尽搜索算法得到最优解.在此基础上研究了多个授权信道情况下的频谱感知效率问题,提出了一种授权信道选择分配方案.仿真结果验证了所提方法的有效性.