The invention relates to the technical field of
signal denoising, and discloses an EWT-TQWT-AFSL-based joint denoising method and
system, and the method comprises the steps: collecting an original ultrasonic
echo signal of a
transformer winding, dividing the original ultrasonic
echo signal into a plurality of adaptive frequency bands through EWT, and generating an intrinsic mode component group comprising a high-frequency component and a low-frequency residual component; performing adjustable Q-value
wavelet transform TQWT on the high-frequency component to obtain a multi-layer
wavelet coefficient set, and performing soft threshold de-noising on each layer of coefficient by adopting an adaptive
threshold function based on
noise variance
estimation; performing fusion reconstruction on the denoised high-frequency component, the unprocessed low-frequency residual component and other reserved components to generate an intermediate
signal; and constructing an adaptive feedback
sparse learning AFSL model, inputting the intermediate
signal, solving a sparse reconstruction
optimization problem through iterative weighting and feedback updating, and outputting a final de-noised signal, thereby effectively solving the technical problem that a traditional de-noising method is difficult to give consideration to both
noise suppression and
signal fidelity in a complex
noise environment.