Design and Implementation of Acoustic Sensing System for Online Early Fault Detection in Industrial Fans

Figure 10

Spectrum feature filtering of acoustic signal.

(a) Original acoustic time-domain signal from an industrial fan

(b) Result of eliminating remaining noise using KLT high-pass filtering

(c) Waveform after applying the Hamming window with a certain bandwidth

(d) Waveform after inverse transform and MFCC signal feature process