一种新的非平稳信号分析方法——局部特征尺度分解法

摘要

在定义瞬时频率具有物理意义的内禀尺度分量(Intrinsic scale component,简称ISC)的基础上,提出了一种新的非平稳信号分析方法——局部特征尺度分解方法(Local characteristic-scale decomposition,简称LCD),该方法能够自适应地将一个复杂信号分解为若干个瞬时频率具有物理意义的内禀尺度分量之和.首先对LCD方法的原理进行了分析,然后给出了采用LCD对信号进行分解的详细步骤,最后采用仿真信号对LCD和经验模态分解(Em-pirical mode decomposition,简称EMD)方法进行了对比分析,结果表明了LCD方法的有效性及在端点效应、迭代次数和分解时间等方面都优于EMD分解方法.%A new nonstationary signal analysis method, namely the local characteristic-scale decomposition (LCD) is proposed in this paper based on the definition of the intrinsic scale component with physical instantaneous frequency. By using LCD method.any complicated signal can be decomposed adaptively into some intrinsic scale components (ISC) whose instantaneous frequencies own physical sense. In this paper, the theory of LCD is analyzed firstly;then the detail step of signal decomposition using LCD is given; finally the LCD method is compared with the empirical mode decomposition (EMD) method by analyzing a simulation signal. The analysis results show that the LCD method is effective and is superior to the EMD method in restraining end effect, the times of iteration and decomposition time.