Ricerc@Sapienza

A closed-form model for the forward scatter radar (FSR) signal is presented with the goal to overcome the far-field (FF) limitation of the commonly used models. The proposed Fresnel closed-form (FCF) model, based on an approximation of the Helmholtz-Kirchhoff electromagnetic theory, correctly represents the received field of rectangular metallic targets crossing the baseline either in the short range or long range of the FSR transmitter and receiver.

This paper is devoted to the estimation of target motion parameters with a forward scatter radar (FSR). To provide an upper bound for the estimation performance, a closed-form expression of the Cramér-Rao lower bound (CRLB) is provided for the main target signal parameters, namely Doppler rate, baseline crossing instant, and main lobe width parameter of the target amplitude modulation pattern.

A generalized electromagnetic model is presented in order to predict the response of forward scatter radar (FSR) systems for air-target surveillance applications in both far-field and near-field conditions. The relevant scattering problem is tackled by developing the Helmholtz-Kirchhoff formula and Babinet's principle to express the scattered and the total fields in typical FSR configurations.

In this contribution, we analyze the forward-scatter cross-section (FS-CS) of three-dimensional (3-D) metallic targets in a forward scatter radar (FSR) system, moving along arbitrary trajectories, in the transition between far- and near-field regions with respect to the receiving antenna. A vector formulation is introduced, together with a simplified approach based on a physical-optics solution of the scattering integral, and validated by means of full-wave numerical evaluations.