Linear-to-circular polarizers using cascaded sheet impedances and cascaded waveplates

摘要

An ultra-wideband linear-to-circular polarizer is disclosed. In accordance with embodiments of the invention, the polarizer includes a plurality of cascaded waveplates having biaxial permittivity or cascaded anisotropic sheet impedances. Each waveplate/sheet has a principal axis rotated at different angles relative to an adjacent waveplate/sheet about a z-axis of a 3-dimensional x, y, z coordinate system. Each waveplate is composed of a unit cell of an artificial anisotropic dielectric. Each sheet impedance is composed of an anisotropic metallic pattern. The polarizer further includes impedance matching layers disposed adjacent the cascaded waveplates/sheets.