该方法源于瞬时频率的概念，它能把动态信号的局部特征正确地在时频域内予以描述。

It stems from the concept of instantaneous frequency, and it can describe accurately the local properties of dynamic data in the time-frequency plane.

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局域波分析方法的重大突破在于用基于信号局部特征的多个基本模式分量来描述信号，并赋予每个基本模式分量具有实际物理意义的瞬时频率。

The main innovations embodied in this method are the introduction of the intrinsic mode functions based on local properties of signals, which make the instantaneous frequency meaningful.

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它的主要思想就是在一个周期内用若干个交流信号瞬时值描述该交流信号波形，并计算出有效值及其它有关参数。

Its main ideas are that the AC waves are described through some AC instantaneous values in a period, and then RMS values and other concerned parameters are worked out.

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