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arXiv · 1903.08217

Magnetic and Combined Field Integral Equations Based on the Quasi-Helmholtz Projectors

Adrien Merlini·Yves Beghein·Kristof Cools·Eric Michielssen·Francesco P. Andriulli
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Abstract

Boundary integral equation methods for analyzing electromagnetic scattering phenomena typically suffer from several of the following problems: (i) ill-conditioning when the frequency is low; (ii) ill-conditioning when the discretization density is high; (iii) ill-conditioning when the structure contains global loops (which are computationally expensive to detect); (iv) incorrect solution at low frequencies due to current cancellations; (v) presence of spurious resonances. In this paper, quasi-Helmholtz projectors are leveraged to obtain a magnetic field integral equation (MFIE) formulation that is immune to drawbacks (i)-(iv). Moreover, when this new MFIE is combined with a regularized electric field integral equation, a new quasi-Helmholtz projector combined field integral equation is obtained that also is immune to (v). Numerical results corroborate the theory and show the practical impact of the newly proposed formulations.

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Adrien Merlini, Yves Beghein, Kristof Cools, Eric Michielssen, Francesco P. Andriulli. 2019-03-19. Magnetic and Combined Field Integral Equations Based on the Quasi-Helmholtz Projectors. https://doi.org/10.1109/tap.2020.2964941

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