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arXiv · 2311.15592

Calderón Strategies for the Convolution Quadrature Time Domain Electric Field Integral Equation

Pierrick Cordel·Alexandre Dély·Adrien Merlini·Francesco P. Andriulli
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Abstract

In this work, we introduce new integral formulations based on the convolution quadrature method for the time-domain modeling of perfectly electrically conducting scatterers that overcome some of the most critical issues of the standard schemes based on the electric field integral equation (EFIE). The standard time-domain EFIE-based approaches typically yield matrices that become increasingly ill-conditioned as the time-step or the mesh discretization density increase and suffer from the well-known DC instability. This work presents solutions to these issues that are based both on new Calderón strategies and quasi-Helmholtz projectors regularizations. In addition, to ensure an efficient computation of the marching-on-in-time, the proposed schemes leverage properties of the Z-transform -- involved in the convolution quadrature discretization scheme -- when computing the stabilized operators. The two resulting formulations compare favorably with standard, well-established schemes. The properties and practical relevance of these new formulations will be showcased through relevant numerical examples that include canonical geometries and more complex structures.

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Pierrick Cordel, Alexandre Dély, Adrien Merlini, Francesco P. Andriulli. 2023-11-27. Calderón Strategies for the Convolution Quadrature Time Domain Electric Field Integral Equation. https://arxiv.org/abs/2311.15592

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