Wavelet Applications in Signal Processing of Aeroengine
Wenfeng Li, Yongsheng Wang, Bailing Zhang, Yong Jiang · 2006
The relationship between the Fourier transform, the short-time Fourier transform, and the wavelet transform is described. The FT uses the entire signal and permits analysis of the frequency distribution of the energy of the signal as a whole; the STFT only has single-resolution localization property in the time-frequency plane; yet, the WT is a newly good tool for local time-frequency analysis and provides multi-resolution property, especially when dealing with the non-steady variable signal. We study the wavelet-based applications in signal processing of aero-engine, such as signal de-noising, singularity detection, multi-scale fault detection, tendency monitoring, and fractal characterization. The engine parameters discussed include the inlet dynamic pressure signal, the engine vibration signal, the compressor signal, the transitional signal, the engine vane ultrasonic testing-signal, the lubricating oil testing-signal, etc.