De-Noising Method for Wayside Train Bearings Acoustic Signal Based on Doppler Shift
The noises with high level from the different positions of the train lead to the difficulty for extraction of the acoustic signal from the train bearings. Thus the de-noising should be carried out to eliminate the influence of the noises. A new de-noising method has been proposed based on the Doppler Shift. With the crazy climber detection algorithm, all the instantaneous frequencies could be extracted. According to the acoustic theory of Morse, the information of the position of these acoustic sources is revealed. Finally, the variable digital filtering was employed to remove the noises from the other positions of the train. A simulation on the signal containing with ten frequency components demonstrated the validity of this method proposed and the useful components of the signal were enhanced.