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arXiv · 1803.04701

Inverse Problem of Diffraction by an Inhomogeneous Solid with a Piecewise Hoelder Refractive Index

Mikhail Medvedik·Yury Smirnov·Aleksei Tsupak
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Abstract

The problem of reconstruction of an unknown refractive index $k(x)$ of an inhomogeneous solid $P$ is considered. The refractive index is assumed to be a piecewise-H\"{o}lder function The original boundary value problem for the Helmholtz equation is reduced to the integral Lippman-Schwinger equation. The incident wave is defeined by a point source located outside $P.$ The solution of the inverse problem is obtained in two steps. First, the "current" $ J = (k^2 - k_0^2)u$ is determined in the inhomogeneity region. Second, the desired function $k (x) $ is expressed via the current $ J (x) $ and the incident wave $u_0.$ The uniqueness of the solution $J$ to the first-kind integral equation is proved in the class of piecewise-constant functions. The two-step method was verified by solving a test problem with a given refractive index. The comparison between the approximate solutions and the exact one approved the efficiency of the proposed method.

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Mikhail Medvedik, Yury Smirnov, Aleksei Tsupak. 2018-03-13. Inverse Problem of Diffraction by an Inhomogeneous Solid with a Piecewise Hoelder Refractive Index. https://arxiv.org/abs/1803.04701

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