Transverse Resolution in 2-D Linear Inverse Scattering by a Multimonostatic/Multifrequency Configuration

This letter addresses the classical problem of estimating the achievable resolution in terms of the configuration parameters and features of the background media in microwave imaging problems. In particular, we focus on the 2-D scalar case and a homogeneous medium, while data are collected in the near field by a multimonostatic multifrequency configuration. An analytical formula is derived to estimate the transverse resolution. The formula is determined by resorting to the evaluation of the point-spread function (PSF) using the weighted adjoint method. The effect of the configuration parameters on the transverse resolution is investigated. Numerical results confirm the spatially varying behavior of the transverse resolution and the accuracy of the proposed formula by assessing the capability to distinguish two nearby objects.