Ultra-Wide Band and Multifunctional Polarization Converter Based on Dielectric Metamaterial

Polarization has always been an important issue in modern communication systems, especially in sensitive measurements. Conventional polarization converters show limited applications due to their large size and narrow bandwidth. In this paper, we demonstrate an ultra-wide band, multifunctional, and highly efficient metamaterial-based polarization converter that is capable of converting a linearly polarized wave into its cross-polarized wave and circularly polarized wave over different frequency bands. The design principle is based on the field transformation theory and the anisotropic plate is made with high/low permittivity strip metamaterials. The simulation results show that the metamaterial-based polarization converter is able to achieve linear-to-linear conversion over 11.5-12.6 GHz, and linear-to-circular conversion over two frequency bands, 3.0-11.5 GHz and 12.6-17.0 GHz, with an average polarization conversion efficiency over 90%. The polarization converter proposed in this paper provides an important stepping stone for future communication systems' polarization control and can also be extended to higher frequency bands.