基于自适应小波包变换的LMS窄带干扰抑制技术

文章将自适应小波包子带树分解算法与LMS自适应算法相结合,利用自适应小波包变换所具有的优良时频局域性和多分辨分析特征,迅速跟踪和准确定位窄带干扰所污染的子带;然后利用自适应LMS算法对受扰子带进行干扰对消,将窄带干扰滤除,在去除干扰的同时,有效地减少了对有用信号的损失。同时,小波包变换提高了LMS算法的收敛速度和稳定性。仿真结果表明,二者的结合使DSSS系统的干扰抑制性能得到进一步提高。

Adaptive wavelet packet transform -based LMS narrowband interference rejection technique

The adaptive wavelet packet transform(AWPT)-based subband tree decomposition algorithm is combined with LMS adaptive algorithm in this paper.It takes advantages of the excellent time-frequency localizing and multiple analysis characters of adaptive wavelet packet transform to track and localize the narrowband interference,and then suppresses the interference with LMS adaptive filters which reject the interference and simultaneously reduce the loss of the useful signal in the corrupted subbands effectively.At the same time,wavelet packet transform improves the convergence rate and stability of LMS algorithm.The simulation results show that the combination of the two algorithms further improves the narrowband interference suppression performance of DSSS systems.