A Low-Profile Design of Polarization Rotation Reflective Surface for Wideband RCS Reduction

Abstract

A novel compact ultrawideband polarization rotation reflective surface (PRRS) with a high polarization conversion ratio (PCR) is proposed. The 90° polarization rotation (PR) is achieved by employing a PRRS-based diagonally symmetric unit cell including two L-shaped strips with two vias and a centered via-less square patch. The air-based substrate of the structure and its overall dimensions equal to 6 × 6 × 3.3 mm3 (i.e., $0.128{\boldsymbol{\lambda \times 0.128{\boldsymbol{\lambda \times 0.07{\boldsymbol{\lambda }_0} $ based on the lowest frequency of the band) provide a low-profile PRRS with a considerable reduction in thickness. The PR bandwidth of the proposed PRRS is 111% with a PCR over 90%. This PRRS is also applied for radar cross section reduction (RCSR), which provides a measured 10 dB RCSR in an ultrawide bandwidth of about 114.4% (6.4∼23.5 GHz, covering C-, X-, Ku-, and K-bands). A good agreement between the simulated and measured results and a fair comparison with the state-of-the-art approaches prove the accuracy and efficiency of the proposed design.