使次系统容量最大化的协作频谱感知性能分析及优化

摘要

针对认知无线电网络中SU数、检测门限、带宽、频谱利用率和次系统容量间关系的分析表明,一方面C-CSS不仅可降低虚警率、提高频谱利用率,还可利用较少的SU实现较高的次系统容量;另一方面在SU数一定且满足目标要求时,C-CSS与T-CSS实现最大次系统容量所要求的检测门限不同.提出协作频谱感知优化算法,利用NP准则通过直接对数学模型求解即可得到使次系统容量最大的SU数和相应检测门限.理论分析和仿真结果均表明,所提算法在保证目标检测率的前提下最大化了次系统容量.%The relationship among SU, detection threshold, bandwidth, spectrum utilization and secondary throughput in cognitive radio networks was analyzed, which indicates the lower false alarm probability, higher spectrum utilization and larger secondary throughput with less SU in C-CSS(censoring based cooperative spectrum sensing), besides, the required detection threshold for maximizing the secondary throughput different with the traditional CSS under given SU number and the objective demand.Based on the NP criticism, an optimal cooperative spectrum sensing algorithm for maximizing the secondary throughput was proposed by solving the mathematic model to obtain the optimal party of SU and detection threshold.Theoretical analysis and simulation results show that the maximized secondary throughput achieved by the proposed optimal algorithm, while maintaining the given detection probability.