KG衰落信道下基于改进能量检测的分组加权协作频谱感知

Grouping Weighted Cooperative Spectrum Sensing Based on Improved Energy Detection under KG Fading Channel

针对传统能量检测精度低且多数协作频谱感知方法未考虑到不同次级用户所处的感知环境对感知性能的影响等问题,提出了一种在Nakagami-Gamma(KG)复合衰落信道下基于改进能量检测的分组加权协作感知方法。该方法首先确定了各次级用户采用改进能量检测时的最优幂指数,以提高单用户感知精度,然后结合了次级用户的多种性能影响因素对次级用户进行分组,通过在各个组内设计合适的加权融合准则,以提高多用户协作感知性能。仿真结果表明,提出的方法在全局平均接收信噪比较低且目标虚警概率一定时,能显著地提高系统检测概率,降低错误检测概率。

The conventional energy detection suffers from low detection accuracy,and most cooperative spectrum sensing methods do not consider the impact of the sensed environment of different secondary users to the sensing performance.A grouping weighted cooperative sensing method based on improved energy detection in NakagamiGamma(KG)composite fading channel is proposed.Firstly,the optimal power index of each secondary user with improved energy detection is determined to improve the sensing accuracy of single user.Then,the secondary users are grouped by integrating multiple performance factors of them.The corresponding weighted fusion criteria are designed in each group to improve the multi-user cooperative sensing performance.Simulation results show that the proposed method can ef fectively improve the system detection probability and reduce the error detection probability with low global average received SNR and a given target false alarm probability.