改进离散平稳小波变换在压力信号消噪中的应用

摘要

提出基于离散平稳小波的改进自适应降噪方法,并将该方法应用于压力信号消噪,取得了优于传统小波消噪的效果.方法利用平稳小波的冗余特性,解决了传统二进小波变换降噪方法在奇异点存在振荡效应的不足,同时将尺度系数的噪声与各层噪声强度不同纳入分析.利用噪声强度估计各分解层阈值,对尺度和小波系数同时进行自适应降噪.将该方法应用于压力信号消噪,并与传统离散二进小波进行比较,证明了方法的可行性和有效性.%An improved self-adaptive de-noising method based on discrete stationary wavelet transform is put forward. The method is used for pressure signal de-noising and get better effect than the traditional discrete binary wavelet de-noising. In this method, the discrete stationary wavelet transform is used to solve the oscillation effects of singular points in signal de-noising by the discrete binary wavelet transform,and the detail coefficients noise and different noise intensity in different level are taken into consideration. The detail and approximation coefficients in each decomposition level are self-adaptive denoised using the thresholds, which are estimated by the noise intensity accordingly. The pressure signal de-noisong experiment is carried out compared with the traditional discrete binary wavelet transform,the feasibility and validity of the mehtod are proved.