A Low-Profile Wide-Angle Multiband Multifunctional Reflective Polarization Conversion Metasurface

A novel multifunctional reflective polarization conversion metasurface (RPCM) is proposed in this letter. The unit cell of the metasurface (MTS) consists of a phase compensation dielectric layer at the top, an elliptical patch with a bent metal strip, a dielectric layer, and a reflective metal plate at the bottom. Simulations demonstrate that the MTS effectively converts a normally incident 45-degree polarized wave into a cross-polarized wave within the frequency bands 7.1–7.65 and 10.9–14.2 GHz, right-handed circularly polarized (RHCP) waves in the 5.33–7.0 GHz band, and left-handed circularly polarized (LHCP) waves in the 7.79–10.5 and 14.64–19.66 GHz bands. The performance under oblique incidence was also investigated, revealing that the introduction of the phase compensation dielectric layer ensures stable polarization conversion across the primary operating frequency ranges, even at a 45-degree incident angle. Notably, the 14.64–19.66 GHz band demonstrates angular stability up to 55 degrees. The underlying physical mechanisms of polarization conversion are examined through surface current analysis and equivalent circuit modeling. A prototype consisting of 20 × 20 unit cells was fabricated and experimentally characterized, with measurements closely matching the simulated results. The proposed MTS offers significant potential for polarization control in applications such as microwave communications.