A Method of Time-frequency Analysis Based on Empirical Mode Decomposition

Aimed at the nonlinear and non-stationary signals, a method of time-frequency analysis which is called HHT based on Empirical Mode Decomposition is introduced. This method makes any complicated set of data to be decomposed into a finite and often small number of Intrinsic Mode Functions through Empirical Mode Decomposition. So the instantaneous frequency defined by Hilbert transform has a meaning. The validity of the method is displayed through experiment. Then it is compared with the available time-frequency analysis methods. Finally, the related problems in this field that need further study are stated.