小波包的移频算法与振动信号处理

Frequency Shift Algorithms of Wavelet Packet and Vibration Signal Analysis

小波包分析方法具有优良的时-频定位特性和对信号的自适庆能力,对于分析瞬态的、时变的或多分量的振动信号是一种有力的工具。由于计算过程中的隔点取值,会造成频带交错。本文分析了形成频带交错的原因,提出了消除频带错位的移频算法,分析效果优于经典的排序法。文中给出了分析实例,对两种算法进行了对比分析。最后将小波包分析与其它时频-分析方法进行了比较。

Wavelet Packet possesses excellent property of time-frequency localization and can effectively extract the feature of signals,so it is a powerful tool for analyzing the transient,time-varying or multiply- component signals.As the sampling at every other points in computation of wavelet packet will cause the frequency aliasing,a frequency shift algorithm of wavelet packet is proposed in this paper.The comparison of wavelet packet with other time-frequency representations of signals is also given.