Boundary Compensation Approacg in Geomagnetic Map Preparation Based on BEMD
Zhao Yuxin
Chang Shuai
Li Wang
Abstract：A boundary compensation method based on bi-dimensional empirical mode decomposition (BEMD)is proposed in this paper to address the boundary effect in preparation of geomagnetic navigation reference map.The local geomagnetic anomaly data are firstly decomposed into components with different scales with BEMD;then for small scale ones instant amplitude and frequency are computed with total Hilbert transform,and the boundary is compensated with self-sampling and feature-matching;whereas for the large scale ones,trigonometric function model is conducted and used to compute the values outside the boundary.After the compensation of local dataset,rectangular harmonic model is used to prepare geomagnetic map.Exper-imental results indicate that BEMD method could better compress the boundary effect of rectangular harmonic analysis,and improve the mapping precision steadily in comparison with other existing methods.
Keywords：geomagnetic anomaly fieldrectangular harmonic modelbi-dimensional empirical mode decomposition (BEMD)total Hilbert transformboundary compensationgeophysics
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 1617-1624 )