Linear-to-circular polarization converter based on a two-dimensional periodic array of inhomogenously filled waveguide

This paper presents a new linear-to-circular polarization converter based on a two-dimensional periodic array of inhomogeneously filled waveguide. Its operation principle is explained using the different propagation constants of two modes excited in the rectangular waveguide filled with a dielectric slab. An experimental prototype operating at 9 GHz is designed and constructed. Measured and simulated results are presented for the designed polarizer. It is shown that a 3dB axial ratio bandwidth of 27% is achieved.