Forward scatter radar modeling: Effects of near field for canonical targets

The forward scatter radar (FSR) operation is investigated in this work considering for the first time the significant effects on the signal detection related to the distances between target and Tx/Rx antennas. Referring to a typical FSR scenario (a movable target crossing the baseline), specific attention is paid to the characterization of the forward-scatter cross-section (FS-CS). Based on a suitable numerical evaluation of diffraction integrals as a function of target/receiver distance, the signal complex envelope has been derived not only in far-field conditions, but also in the near-field Fresnel region, for some reference scatterer shapes and related FS-CS. According to standard procedures, the overall FS amplitude and phase signature of typical conductive targets have been evaluated as a function of the parameters involved. The relevant results allow for a deeper analysis of the performance and criticalities of FSR in practical conditions.