基于信噪比加权的协作频谱感知方法

摘要

In cognitive radio,cooperative spectrum sensing can significantly improve the performance of spectrum sensing.Howev⁃er,traditional cooperative spectrum sensing algorithms usually use equivalent weights for data fusion without considering the difference among SNRs of SUs in a real communication environment.According to this situation,a method of SNR⁃based weighted cooperative spec⁃trum sensing is researched.In this paper,we assign different weights to local decisions of different users according to their SNR impact factors.Based on this research,we redefine the SNR impact factor which reduces the influence to sensing performance from extreme SNR values.Simulation results show that,in the AGWN channel and non⁃fading environment,the performance of SNR⁃based weighted cooper⁃ative spectrum sensing is much better than traditional cooperative spectrum sensing and is further improved after redefining the impact factor.%认知无线电中协作频谱感知技术能显著提高频谱感知性能，但传统协作频谱感知算法大多采用等权重进行数据融合，未考虑在实际通信环境中感知用户的信噪比差异。针对这种情况，提出了一种基于信噪比加权的协作感知方法，根据信噪比影响因子的不同，给感知用户本地判决结果分配不同的权重，并在此基础上对影响因子定义做了改进，减小了信噪比极值对感知性能的影响。仿真结果表明，在AWGN信道非衰落环境中，基于信噪比加权的协作感知比传统协作感知性能要好，改进后的加权感知方法对感知性能又有进一步的改善。