Doppler Shift Elimination Method based on Instantaneous Frequency Estimation for the Wayside Acoustic Signal

The phenomenon of Doppler Shift leads to the difficulty for fault diagnosis of train bearings with a high moving speed. So the elimination of the Doppler shift should be implemented firstly. A Doppler Shift elimination method for the wayside acoustic signal is proposed. The instantaneous frequency estimation based on STFT was applied to attain the IF vector. According to the acoustic theory of Morse, the data fitting was then carried out to achieve the fitting IFs, with which the re-sampling sequence could be established to eliminate Doppler Shift. To demonstrate the validity of this method, an experiment with the synthetic signal containing several frequency components had been carried out. The results show that the re-sampled signal was revised without Doppler Shift.