A novel integral equation for scattering by locally rough surfaces and application to the inverse problem

Haiwen Zhang; Bo Zhang

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arXiv · 1302.0161

A novel integral equation for scattering by locally rough surfaces and application to the inverse problem

Haiwen Zhang·Bo Zhang

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Abstract

This paper is concerned with the direct and inverse acoustic or electromagnetic scattering problems by a locally perturbed, perfectly reflecting, infinite plane (which is called a locally rough surface in this paper). We propose a novel integral equation formulation for the direct scattering problem which is defined on a bounded curve (consisting of a bounded part of the infinite plane containing the local perturbation and the lower part of a circle) with two corners. This novel integral equation can be solved efficiently by using the Nystrom method with a graded mesh introduced previously by Kress and is capable of dealing with large wavenumber cases. For the inverse problem, we propose a Newton iteration method to reconstruct the local perturbation of the plane from multiple frequency far-field data, based on the novel integral equation formulation. Numerical examples are carried out to demonstrate that our reconstruction method is stable and accurate even for the case of multiple-scale profiles.

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Haiwen Zhang, Bo Zhang. 2013-02-01. A novel integral equation for scattering by locally rough surfaces and application to the inverse problem. https://arxiv.org/abs/1302.0161

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