Time domain approach to inverse scattering

A plane wave is considered incident upon a medium, the inhomogeneities of which can vary arbitrarily in three-dimensional space, except that changes in wave polarization must be negligible. Observation of the scattered field is assumed over a plane. An algorithm for reconstructing the inhomogeneous frequency-independent refractive index is outlined. The analysis, which is conducted wholly in the time domain, is introduced by a discussion (supported by numerical examples) of several scattering problems involving a single-space dimension.