Spillover Mitigation Method in Rotman Lens-Based Retrodirective Arrays

This paper presents a new method to compensate for spillover loss in Rotman lens-based retrodirective arrays. The proposed approach aims to minimize the radar cross section (RCS) variation across the full field-of-view (FoV) of ±30° and the operating bandwidth of 24-24.25 GHz. By proper phase correction transmission line (TL) design at the array side and compensating for phase errors between adjacent beamports, the method significantly reduces the initial RCS variation from 25 dB to 3.2 dB over the 30° scan angle. The results demonstrate improved performance in maintaining a more uniform RCS across the entire FoV, contributing to enhanced retrodirective array functionality.