Transverse Resolution in Microwave Imaging for Strip Objects Buried in a Half-Space Medium

In this paper we are concerned with a microwave imaging problem for a non-magnetic two-layered background medium, where objects are buried in the lower half-space, and the scattered field is collected in the upper one according to a multi-monostatic configuration. In particular, we are interested in estimating the achievable transverse resolution. As well known, range resolution mainly depends on the working frequency band whereas transverse resolution depends on the geometrical parameters of the configuration and is usually computed in correspondence to the highest (or even the average) adopted frequency. Determining transverse resolution is much more difficult, and closed form estimations have been actually found only for the case of unbounded observation domain. However, in real scattering scenarios, measurements have to be necessarily collected under an aspect limited setup. Therefore, in order to fill such a theoretical gap, here the focus is on the estimation of transverse resolution for bounded observation domains. To this end, we consider a single-frequency 2D scalar prototype configuration where the buried scattering object domain is represented by a strip parallel to the half-space interface. More in detail, we succeed in finding an analytical estimation of the transverse resolution which highlights the role of the configuration parameters as well as the dielectric permittivity of the lower half-space.