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arXiv · 1404.3451

A fast direct solver for high frequency scattering from a large cavity in two dimensions

Jun Lai·Sivaram Ambikasaran·Leslie F. Greengard
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Abstract

We present a fast direct solver for the simulation of electromagnetic scattering from an arbitrarily-shaped, large, empty cavity embedded in an infinite perfectly conducting half space. The governing Maxwell equations are reformulated as a well-conditioned second kind integral equation and the resulting linear system is solved in nearly linear time using a hierarchical matrix factorization technique. We illustrate the performance of the scheme with several numerical examples for complex cavity shapes over a wide range of frequencies.

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Jun Lai, Sivaram Ambikasaran, Leslie F. Greengard. 2014-04-14. A fast direct solver for high frequency scattering from a large cavity in two dimensions. https://arxiv.org/abs/1404.3451

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