An automatic correction method of marine radar rainfall image based on continuous wavelet transform

Abstract

The aim of the difficult processing of marine radar image data affected by rainfall, in the case of comprehensively considering the influence factors of rainfall on marine radar image, this paper proposes an automatic correction method for marine radar rainfall image based on continuous wavelet transform. Firstly, according to the characteristics of the marine radar echo data, the radial data of the marine radar image is decomposed by empirical orthogonal functions, and the structural characteristics of the matrix data are analyzed to extract the data characteristic quantity. Then, considering the characteristic information of the data, combined with the advantages of complex Gaussian wavelet and Daubechies Wavelet transform in time–frequency domain with good resolution and hierarchical nature, each radial profile data decomposed based on empirical orthogonal function is processed by two kinds of wavelet transform, which improves the accuracy of the damaged image correction. Finally, the radial data after the two transformations are fused by wavelet inverse transformation and adaptive weighted fitting, and the influence of rainfall on the marine radar image is corrected to the greatest extent. The advantages and applicability of the algorithm are illustrated by the comparison chart of the noise details after the magnification of the marine radar rainfall image before and after the correction, the statistical histogram of the reconstructed wave field data of the main mode before and after the correction, and the comparison table of the heterogeneous data distribution.

Keywords

• Marine radar image
• Continuous wavelet transform
• Self-correction
• Rainfall disturbance
• Empirical orthogonal function decomposition