局部均值分解方法在调制信号处理中的应用

Application of Local Mean Decomposition Method to the Processing of Modulated Signals

为了提取多分量调制信号的调制信息,研究了一种信号分析方法——局部均值分解(local mean decomposition,简称LMD)方法。LMD方法首先将一个多分量的调制信号自适应地分解成若干个具有一定物理意义的PF(product function)分量,其中每个PF分量为一个包络信号和一个纯调频信号的乘积,然后求出每个PF分量的瞬时幅值与瞬时频率,从而获得原信号完整的调制信息。本文用LMD方法对仿真信号以及齿轮故障振动信号进行了分析,结果表明该方法能有效地提取出信号的调制信息。

In order to extract modulating information from the multi-component modulated signal.A new signal analysis method,the local mean decomposition(LMD), is researched in this paper.The LMD firstly decomposes the multi-component modulated signal into a set of product functions,each of which is the product of an envelope signal and a frequency modulated signal from which instantaneous amplitude and frequency can be derived.Accordingly,the integrity modulating information can be obtained.In this paper,the LMD is applied to a simulated signal and a gear fault vibration signal,and the results show that the modulating information of the signals can be extracted effectively.