SFB selection method and its application in engine waveform analysis and fault diagnosis

A novel signal processing method, called sensitive frequency band (SFB) selection, is proposed based on the correlation coefficients between the original signal and its reconstructed approximation and detail parts. By identifying the noised-related and fault-related SFBs, the SFB selection method can be used to reduce noise and extract fault feature effectively for a signal. This method is applied to analyze the engine injector-pulse-width waveforms, and it works well for engine waveform analysis and fault diagnosis. This study will also supply a good reference for signal processing in the other research fields.