Abstract: The instantaneous characteristics of non-stationary signal are analyzed. Then non-stationary signal are transformed by using harmonic wavelet, and the relation between the wavelet coefficient and the instantaneous characteristics of non-stationary signal are introduced. The principle and method of the accurate extraction for the instantaneous characteristics of non-stationary signal by using harmonic wavelet transforms are presented. Examples of application demonstrate that this method presented can effectively extract the instantaneous characteristics of special components in the non-stationary signal and has high precision and good noise resisting ability. This method can realize simple and quick algorithm through Fourier transform, and real-time analysis of instant taneous characteristics of non-stationary signal.

Key words: Characteristic extraction, Harmonic wavelet transforms, Instantaneous characteristic, Non-stationary signal