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arXiv · 2305.15310

Direct sampling method via Landweber iteration for an absorbing scatterer with a conductive boundary

Rafael Ceja Ayala·Isaac Harris·Andreas Kleefeld
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Abstract

In this paper, we consider the inverse shape problem of recovering isotropic scatterers with a conductive boundary condition. Here, we assume that the measured far-field data is known at a fixed wave number. Motivated by recent work, we study a new direct sampling indicator based on the Landweber iteration and the factorization method. Therefore, we prove the connection between these reconstruction methods. The method studied here falls under the category of qualitative reconstruction methods where an imaging function is used to recover the absorbing scatterer. We prove stability of our new imaging function as well as derive a discrepancy principle for recovering the regularization parameter. The theoretical results are verified with numerical examples to show how the reconstruction performs by the new Landweber direct sampling method.

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Rafael Ceja Ayala, Isaac Harris, Andreas Kleefeld. 2023-05-24. Direct sampling method via Landweber iteration for an absorbing scatterer with a conductive boundary. https://arxiv.org/abs/2305.15310

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