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arXiv · 2508.18205

An RBF-based method for computational electromagnetics with reduced numerical dispersion

Andrej Kolar-Požun·Gregor Kosec
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Abstract

The finite difference time domain method is one of the simplest and most popular methods in computational electromagnetics. This work considers two possible ways of generalising it to a meshless setting by employing local radial basis function interpolation. The resulting methods remain fully explicit and are convergent if properly chosen hyperviscosity terms are added to the update equations. We demonstrate that increasing the stencil size of the approximation has a desirable effect on numerical dispersion. Furthermore, our proposed methods can exhibit a decreased dispersion anisotropy compared to the finite difference time domain method.

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Andrej Kolar-Požun, Gregor Kosec. 2025-08-25. An RBF-based method for computational electromagnetics with reduced numerical dispersion. https://doi.org/10.1016/j.cma.2026.118865

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