Edge Detection Method of Multiple Magnetic Sources under the Condition of Oblique Magnetization

doi:10.3969/j.issn.1000-1093.2020.10.013

Abstract

Abstract: The traditional edge detection method has poor recognition ability for multi-magnetic source targets under the condition of oblique magnetization. An edge detection method of multiple magnetic sources under the condition of oblique magnetization is proposed. The components of magnetic field are transformed into total magnitude anomaly and direction cosines according to vector composition principle, and an improved K singular value decomposition denoising model is proposed to reconstruct the magnetic data. The magnetization direction of each magnetic source is estimated by correlation between normalized magnetic source strength and a general phase transformation of the total magnetic intensity. The magnetic gradient tensor is transformed into the tensor data, which would be produced by the same sources with vertical magnetization. The horizontal edges of multiple magnetic sources are estimated from the ratio of the sum of the absolute values of the matrix eigenvalues of the transformed magnetic gradient tensor to the gradient component of magnetic field component along the direction of z axis in the direction of z axis. The method is tested both on synthetic magnetic data and real magnetic data. The results show that the proposed method considerably reduces the effects of oblique magnetization, and has a good ability to resist noise.

Key words: magneticsource, edgedetection, improvedKsingularvaluedecomposition, magnetizationdirection, magneticgradienttensor

CLC Number:

P318.6⁺3

LI Jinpeng, FANG Hongbo, ZHANG Yingtang, LI Zhining, YIN Gang. Edge Detection Method of Multiple Magnetic Sources under the Condition of Oblique Magnetization[J]. Acta Armamentarii, 2020, 41(10): 2033-2044.

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第41卷第10期2020 年10月
兵工学报ACTA ARMAMENTARII
Vol.41No.10Oct. 2020

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