Dipole-Moment Source Modeling Using Near-Field Scanning With a Finite-Impulse-Response Filter

• Published in: IEEE transactions on electromagnetic compatibility Vol. 65; no. 5; pp. 1 - 10
• Main Authors: Tsai, Min-Hsu, Chen, Wei-Kai, Huang, Ming-Chung, Wu, Ruey-Beei
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Dipole moments; Electric dipoles; Electromagnetic interference; equivalent dipole moment model; finite impulse response (FIR) filter; Finite impulse response filters; FIR filters; Integrated circuit modeling; Iterative methods; Least squares method; Magnetic dipoles; Magnetic moments; Magnetic resonance imaging; Magnetic separation; Near fields; near-field scanning; Phase measurement; Regularization; Semiconductor device measurement; tikhonov regularization
• ISSN: 0018-9375; 1558-187X
• DOI: 10.1109/TEMC.2023.3296139

This article demonstrates that if 2-D divergence operations are used, the electric and magnetic fields in the planar near-field are, respectively, determined using the underlying equivalent electric dipole moments and magnetic dipole moments. A finite impulse response (FIR) filter is used to rapidly determine a feasible dipole moment model using the 2-D divergence of near-field scanning fields. To increase the accuracy of the solution, an iterative process that uses a FIR filter with a least-squares method is proposed. The regularization technique for stabilizing the least-squares solution is studied and a criterion for the selection of regularization coefficient is derived. The proposed method is validated using several examples and is compared with the conventional method, capable of obtaining a more accurate solution in significantly less computation time.