Abstract

This paper is concerned with the electromagnetic inverse scattering problem that aims to determine the location and shape of anisotropic scatterers from far field data (at a fixed frequency). We study the orthogonality sampling method, which is a simple, fast, and robust imaging method for solving the inverse scattering problem. We provide a theoretical analysis as well as a stability estimate for the sampling method. An equivalent relation between the orthogonality sampling method and the direct sampling method is also established. The analysis uses the Factorization method for the far field operator, and it plays an important role in the justifications along with the Funk--Hecke integral identity. Finally, we present some numerical examples to validate the performance of the sampling methods for anisotropic scatterers in three dimensions.