Denoising and simplification of deep-sea sound speed profiles based on wavelet transform

Sound speed correction is a critical component of multibeam bathymetry. To address the issue of low system computational efficiency caused by the high number of sampling points in deep-sea sound speed profiles, a simplification method based on wavelet transform is proposed. Initially, the measured sound speed profiles are subjected to wavelet denoising and low-frequency coefficients obtained from wavelet decomposition are then used to construct the contour of the denoised sound speed profiles. Next, extreme values are extracted to simplify the denoised sound speed profiles. Finally, the constant gradient ray tracing method is utilized to quantitatively analyze the accuracy of ray tracing for the simplified sound speed profiles. The results indicate that the simplification rate of the sound speed profiles obtained through this method exceeds 98%, with the depth errors remaining within the limits prescribed by the IHO Standards for Hydrographic Surveys. This method effectively enhances the computational efficiency of the multibeam system and has practical application value.