一种新颖的多用户协作频谱检测算法

A Novel Spectrum Sensing Algorithm Based on Multi-user Collaboration

频谱检测是认知无线电的一项核心技术,其检测性能容易受到信道衰落的影响.与单用户频谱检测相比较,多用户频谱检测能够克服认知无线电中衰落环境对系统检测性能的影响.文章分析了能量检测在高斯信道、瑞利衰落信道和阴影衰落信道下的检测性能,提出了一种新的多用户协作频谱检测数据融合算法.该方法采用1 bit的双极性信号表示单节点认知用户能量检测的判决结果并送至融合中心,融合中心根据每个认知用户的信噪比进行加权融合.仿真结果表明,该算法能够更加有效地克服信道衰落对频谱检测性能的影响,其检测性能明显优于OR准则算法.

The spectrum sensing technology is a key technology of cognitive radio.In fading environments,the performance of spectrum sensing would be affected and fall down.Compared with single-user spectrum sensing,multi-user collaborative spectrum sensing can combat the effect of fading.Based on analysis of the performance of energy detection in Gauss,Rayleigh and shadow fading channels,a new data fusion algorithm for multi-user collaborative spectrum sensing is proposed,in which 1-bit bipolar signal is used to represent the decision of spectrum detection of single cognitive user and send to the fusion center,which fuses the local the decisions of spectrum detection according to each cognitive user′s signal-to-noise ratio.Simulation results indicate that the algorithm can weaken the effect of fading on the performance of spectrum sensing effectively,and its performances are better than the OR-rule obviously.