Abstract The aircraft engine ECT oil monitoring data is affected by various noises during the acquisition and transmission process, which affects the extraction of effective features of the data. A double wavelet denoising (DWAD) algorithm is proposed for this problem. In the two wavelet domains, the data is decomposed, filtered by the threshold function, and the difference of the wavelet coefficient distribution is used to force the denoising signals in the two wavelet domains to be the same. The inverse tangent function is used as a penalty function to obtain a more sparse coefficient expression. The experimental results show that compared with the traditional wavelet denoising method, the average signal-to-noise ratio of continuous signal and step signal is improved by 2.3dB and 4.2dB, the denoising effect is optimized.
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2021, Vol. 42 
