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arXiv · 1806.10433

Electromagnetic shielding by thin periodic structures and the Faraday cage effect

Bérangère Delourme·David P. Hewett
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Abstract

In this note we consider the scattering of electromagnetic waves (governed by the time-harmonic Maxwell equations) by a thin periodic layer of perfectly conducting obstacles. The size of the obstacles and the distance between neighbouring obstacles are of the same small order of magnitude $\delta$, $\delta$ being small. By deriving homogenized interface conditions for three model configurations, namely (i) discrete obstacles, (ii) parallel wires, (iii) a wire mesh, we show that the limiting behaviour as $\delta\to0$ depends strongly on the topology of the periodic layer, with full shielding (the so-called "Faraday cage effect") occurring only in the case of a wire mesh.

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Bérangère Delourme, David P. Hewett. 2018-06-27. Electromagnetic shielding by thin periodic structures and the Faraday cage effect. https://arxiv.org/abs/1806.10433

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