小波包时频分析及其特性

在两种典型的非平稳信号分析方法--小波包变换与短时傅里叶变换的基础上,综合两种方法的优点,提出了小波包时频方法.建立了相应的小波包时频分量谱、小波包时频分量幅度谱、小波包时频谱、小波包时频幅度谱等概念.证明了小波包时频分析的能量守恒性,形成了一套较完善的分析体系.算例表明,该分析方法在诊断奇异、检测信号深层次细节等方面具有一些独特性质.

Wavelet Packet Time-Frequency Analysis and Its Property

Based on two typical methods for analyzing nonstationary signals, the wavelet pa cket transform and the short time Fourier transform(STFT), a method named wavelet packet time frequency analysis(WPTFA) was put forward. Four concepts related to the WPTFA method were defined, which were wavelet packet time frequency compo nent spectrum, amplitude spectrum of wavelet packet time frequency component, wavelet packet time fequency spectrum, amplitude spectrum of wavelet packet time frequency. Energy conservation of WPTFA was proved and the method of using WPT FA was presented. Two examples demonstrated some special merits of WPTFA in iden tifying singularities and other details of signals.