Compact Extended Scan Range Antenna Array based on Rotman Lens

This article proposes an innovative method for extending the scan range of phased arrays based on Rotman lens by a factor two. The main objective is to take advantage of the performance of the Rotman lens as beamforming network, resolving its intrinsic increase of phase error and coupling losses when wide scan angles are required. The proposed concept aims to overcome these limitations by introducing the combination of two specific operations called “complete beam shifting (CBS)” and “beam mirroring (BM).” The described technique is applied to a 24 GHz scanning array antenna system, designed and manufactured by taking into consideration fabrication and related cost issues. Finally, the proposed concept has been validated through measurements.