巴特沃斯小波变换算法在故障诊断中的应用

提出了一种基于巴特沃斯滤波器的离散小波变换快速算法 ,通过控制巴特沃斯滤波器的频率截止特性来抑制小波变换中的频率混迭现象 ,还可通过控制各小波函数对应的巴特沃斯滤波器的截止频率位置来改变离散小波变换的频率分辨率 ,实现 1 / 1频程 (二进小波变换 )、1 / 3频程、1 / 6频程等高频率分析精度的离散小波变换

Butterworth Based on Discrete Wavelet Transform and Its Application in Machine Fault Diagnosis

To improve the frequency alias and the frequency resolution of the discrete wavelet transform, a Butterworth based algorithm for the efficient computation of the discrete wavelet transform is presented. By changing the order of the Butterworth filter, the magnitude response of the wavelet function can be controlled and the frequency alias in the wavelet transform can be restrained. By changing the cut frequency of the Butterworth filter, the scale dilation of the wavelet family can be controlled, and the frequency resolution of the wavelet transform can be improved form the 1/1 octave of the discrete dyadic wavelet transform to 1/3 octave, 1/6 octave or higher. The algorithm is suitable to use in the machine fault diagnosis, where a low frequency alias and a high frequency resolution are needed.