局部特征尺度分解方法及其分解能力研究

摘要

A adaptive time-frequency analysis method, local characteristic-scale decomposition (LCD), is proposed based on the study of intrinsic time-scale decomposition (ITD). By using the presented method, a complicated multi-component signal could be adaptively decomposed into the summation of a number of physically meaningful intrinsic scale components (ISC) with instantaneous frequencies. After expatiation on the basic principle of LCD, a research model was built to investigate the effects of frequency ratio, amplitude ratio and initial phase difference of the component signals, and iteration number of the single component on decomposition capacities of LCD, respectively. Finally, the needed conditions were offered that the multi-component signals could be processed well by LCD.%在研究内禀时间尺度分解(Intrinsic Time-Scale Decomposition,ITD)方法的基础上提出了一种新的自适应时频分析方法——局部特征尺度分解(Local Characteristic-scale Decomposition,LCD)方法,该方法可以自适应地将一个复杂的多分量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(Intrinsic Scale Component,ISC)之和.对LCD方法的基本原理进行了阐述,通过建立分解能力研究模型分别研究了分量信号的频率比、幅值比和初相位差以及单个分量迭代次数对LCD方法分解能力的影响,并给出了多分量信号可由LCD方法分解的大致条件.