利用LMS的频谱感知算法

Spectrum Sensing Method Using LMS

针对低信噪比下的频谱感知问题,提出一种基于最小均方算法(LMS)的不受噪声不确定度影响的频谱感知算法。本文利用LMS算法对原始发送信号的幅度进行实时估计,并以其估计值作为检验统计量,判断主用户是否存在,实现频谱感知。理论和仿真结果均表明,此方法对微弱信号的检测能力较强,且性能明显优于能量检测算法,通过对噪声方差的实时估计,可以有效克服噪声不确定度的影响。

In order to fulfill the spectrum sensing in low SNR environment,the based LMS spectrum sensing method that free of noise uncertainty is proposed. In this paper,LMS algorithm is applied to estimate the amplitude of transmitted signal in real time,and the estimation is employed as the test statistic to detect the existence of primary user. Both the theoretical and simulation results show that the proposed method has better performance for weak signal detection,which also greatly outperforms the classical energy detection method and effectively overcome the influences of noise uncertainty by estimating the noise variance.