A Broadband Metasurface for Cross Polarization Conversion Applications

A reflective broadband cross polarization conversion (CPC) metasurface operating in microwave frequency regime is simulated and presented in this paper. The metasurface is a periodic arrangement of unit cells and each unit cell consists of a metallic circular split ring resonator (C-SRR) with a circular loop inside it. A linearly-polarized or circularly polarized wave is transformed into its orthogonal counterpart when reflected back from the metasurface. Four plasmonic resonances at different frequencies is the reason behind broadband CPC operation achieving 3dB fractional bandwidth of 107% from 4.2-13.9 GHz. The proposed design has the highest reported 3dB fractional bandwidth made on a lossy single layer FR4 substrate for normal incidence. The designed metasurface is useful in manifold practical applications for polarization control devices.