Systematic Design of Transmission-type Polarization Converters Comprising Multi-layered Anisotropic Metasurfaces

A simple but efficient approach for the synthesis of transmission-type wideband polarization converters is presented. The proposed configuration comprises multilayer metasurfaces including resonant particles which are progressively rotated layer by layer. The progressive rotation of the particles allows for a polarization conversion over a large frequency band. The polarizing structure is efficiently designed and optimized through a transmission line model approach handling the cascade of anisotropic impedance layers and dielectrics. An optimized 8-layers design based on gradually rotated dipole resonators is presented as a proof of concept. The results obtained through the efficient transmission line model are compared with full-wave simulations once that the structure was optimized showing satisfactory agreement. A prototype of the wideband polarization converter has been fabricated and measured.