A linear to circular polarization converter based on Jerusalem-Cross frequency selective surface

In this paper a transmission type polarizer is presented to convert linear polarization to circular polarization. Based on a frequency-selective surface, this polarizer consists of Jerusalem Crosses printed on a RT 5870 substrate. The tuning of inductive arms and capacitive coupling between the unit cells have helped in achieving desired axial-ratio performance for the transmitted wave. The polarizer works at 17.8 GHz and provides the required 90° phase difference between the two orthogonal components, which are equal in magnitude. The structure provides around 99% polarization purity at the resonance. Theoretical analysis and results of numerical investigations related to the structure are presented.