Design of a Wideband Linear-to-Circular Polarizing Reflector for Ka-band Satellite Applications

This contribution presents a low-profile linear-to-circular polarizing reflector with wideband operation in Kaband. The polarizing cell consists of three parallel dipoles placed with 45° slant with respect to the direction of the incident linearly polarized field. The lengths of the dipoles are adjusted cell by cell through a dual-frequency optimization process, which accounts for the real incidence angles on each cell. A 25x25 cm flat polarizing reflector prototype has been fabricated and tested to validate the concept. The measured axial ratio is lower than 1.8 dB within the 19-30 GHz band (a relative bandwidth of 45%), and good matching with the simulations is obtained. The proposed polarizing reflector has applications in novel multibeam antenna configurations for Ka-band satellites.