Based on the local characteristics of signals, a local wave method (LWM) can be employed to obtain the instantaneous frequency of signals and the Hilbert time frequency spectrum composed of an energy time frequency three dimensional distribution.

• 局域波法是基于信号局部特征 ,通过该方法可得到信号的瞬时频率和构成能量 -时间 -频率三维分布的Hil bert时频谱。