认知无线电网络用户合作机会接入方案的研究

Secondary User Cooperative Opportunistic Access Scheme in Cognitive Radio Networks

认知无线电技术可以用来解决随着无线通信的迅速发展而突显出来的频谱实际利用率不高的问题,并缓解频谱分配紧张的局面.本文所关注的是多个认知无线电用户(SU)的机会频谱接入问题.分布式认知无线电网络中,为避免和授权用户(PU)发生冲突,通常采用周期性感知方法,这将使吞吐量降低.本文提出了一种认知无线电用户间高效的合作方案.文中分析了用户合作的最好和最坏两种情况下系统吞吐量的解析解.通过仿真验证了理论结果,并比较分析几种方案下每个用户和系统吞吐量随用户数量的变化,得出了用户间有效的合作可以提高各自以及整个系统的吞吐量的结论.

Cognitive radio technology has been considered in order to improve the utilization of licensed spectrum and solve the problem that less and less frequency resources are available for future wireless applications. This paper looks into the opportunistic spectrum access of multiple secondary users.In distributed cognitive radio networks,the general periodic sensing method leads to a low throughput. In this paper, we present an efficient cooperation opportunistic spectrum access scheme. The best and worst cooperation situations are analyzed, and the theoretical results of the throughput in each situation are deduced. Simulations and comparisons validated theoretical results,and the throughput of each member in the cooperation group and the system throughput are improved by cooperation.