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arXiv · 2004.09878

On the Spectral Behavior and Normalization of a Resonance-Free and High-Frequency Stable Integral Equation

Tiffany L. Chhim·Simon B. Adrian·Francesco P. Andriulli
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Abstract

The CFIE used for solving scattering and radiation problems, although a resonance-free formulation, suffers from an ill-conditioning that strongly depends on the frequency and discretization density, both in the low- and high-frequency regime, resulting in slow convergence rates for iterative solvers. This work presents a new preconditioning scheme for the CFIE that cures the low- and the high-frequency as well as the dense discretization breakdown. The new preconditioner for the CFIE is based on a spherical harmonics analysis and the proper regularization with Helmholtz-type operators. Numerical results have been obtained to prove the effectiveness of this new formulation in real scenarios.

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Tiffany L. Chhim, Simon B. Adrian, Francesco P. Andriulli. 2020-04-21. On the Spectral Behavior and Normalization of a Resonance-Free and High-Frequency Stable Integral Equation. https://doi.org/10.1109/apusncursinrsm.2018.8608769

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