基于EMD的信号瞬时频率估计

Estimating the instantaneous frequency of a signal based on EMD

分析了信号瞬时频率的定义及其两种主要的获得信号相位的方法:解析信号法和正交模型法.提出了一种基于经验模式分解的新的瞬时频率估计方法——正交包络法.该方法计算简单,克服了正交模型法无法由一个时间函数确定两个时间函数的困难.与Hilbert变换方法相比,正交包络法使边界问题得到了明显改善.实验证明这是一种有效的瞬时频率估计方法.

We analyze the concept of the instantaneous frequency of a signal and the two methods of obtaining the phase of a signal, i.e. analytical method and orthogonal method. We propose a new method, i.e. the orthogonal envelope method, to estimate the instantaneous frequency based on EMD. The orthogonal envelope method is easy in calculation and it overcomes the difficulty of orthogonal method in creating two time functions by one. Comparing with Hilbert transform, the orthogonal envelope method is better in dealing with border effects. The results of experiment show that the orthogonal envelope method is effective to estimate the instantaneous frequency.