Study on Engine Vibration Signal Denoising Method of SURE Block Threshold Based on DT-CWPT

A mechanical vibration signal denoise method of SURE block threshold based on DT-CWPT was proposed. The mechanical condition monitoring is always aims to removing the background noise and preserving the useful information more effectively. The presented method chooses the threshold level and block size by minimizing Steinpsilas unbiased risk estimate which is more adaptive and superior performance and can obtain higher signal-to-noise than the common NeighCoeff. Simultaneously, combine the method with the DT-CWPTpsilas characteristic of approximately shift-invariant and optimal representation for the signal. And the method was applied to denoise the engine vibration signal which has the property of complex frequency domain and nonstationary and time-variant. Testing results show that the proposed method can effectively compress the noise and the denoised signal has better classification performance.