Localizing metallic small spheres by a linear distributional approach

The problem of determining the number and the locations of "small" metallic spheres from scattered far-field measurements under plane waves incidence is considered. The problem is formulated by neglecting the mutual scattering between the spheres and by representing their locations as the support of delta-functions. This allows to cast the problem as the inversion of a linear integral operator we tackle by means of a Truncated Singular Value Decomposition. The performance of the inversion scheme are analyzed for both the cases of a multi- view/single-frequency and a single-view/multi-frequency configuration by exploiting synthetic exact data.