Multiband linear and circular polarization converting anisotropic metasurface for wide incidence angles

In this paper, a metasurface-based multi-band polarization converter is designed and demonstrated. The designed metasurface not only converts horizontal polarization into vertical and vice versa, but also exhibits linear-to-circular and circular-to-linear polarization conversion. The proposed design efficiently converts linearly polarized incident wave into cross-polarized wave within three frequency bands: 6.3–6.6 GHz, 9–10.8 GHz and 15.2–18.7 GHz. Similarly, linear-to-circular and circular-to-linear polarization conversion is achieved in six frequency bands: 6–6.1 GHz, 6.9–7 GHz, 7.1–7.2 GHz, 8–8.7 GHz, 11.3–13.4 GHz and 13.5–14.5 GHz. Moreover, both linear-cross and linear-to-circular polarization conversion maintain their conversion efficiencies against variations in the incidence angle. The physical mechanism is explained using surface current distribution. The proposed metasurface is validated by full wave simulation and experimental measurements. (paper)