Efficient extraction of the wavelet ridge for asymptotic signal analysis

Utilizing the property of the continuous wavelet transform (CWT) of asymptotic signals when both the scale and the signal are discrete, we propose a new approach for ridge extraction. A more reliable ridge is formed by using only the discontinuity points on the ridge extracted by the conventional method. Inequalities are derived to state that the scale interval and the sampling frequency depend on the parameters of the Morlet wavelet function and the instantaneous frequency of the signal. The edge effect regions are determined and removed from the effective CWT coefficients. The efficiency and practicability of the proposed method are confirmed through a system identification simulation.