An effective metasurface-based linear and circular polarization converter for C- and X-band applications

In this study, a reflection-mode metasurface-based linear and circular polarization converter is designed for common microwave frequencies (C-band (5.85–8.20 GHz) and X-band (8.20–12.40 GHz)). The proposed polarization converter possesses a right-handed circular polarization (RHCP) capability in the 5.35–5.94 GHz frequency range and a left-handed circular polarization conversion (LHCP) capability in the 8.88–12.03 GHz frequency range. Besides its circular polarization converter capability, it demonstrates linear polarization transformation in the 4.61–4.85 GHz and 6.86–7.78 GHz frequency ranges with a polarization converter rate (PCR) greater than 90%. The design provides an oblique incidence performance up to 45° with 80% PCR value in linear polarization. The CST Microwave Studio (a commercial 3D electromagnetic simulator) was used to obtain simulation results of the design. For validation, the designed converter was first fabricated using the conventional circuit-board method, and then its reflection coefficient was measured by a microwave measurement setup calibrated by the thru-reflect-line method. A good agreement was observed between simulated and experimental results. Finally, the proposed converter design was compared with other converter designs in the literature to examine its effectiveness.