Reflection-Phase Calculation of Circularly Polarized Folded Reflectarray Antennas with Low Profile, High Efficiency, and Arbitrary Aperture Distribution

Abstract

This paper presents a new concept of designing circularly polarized folded reflectarray (CPFRA) antennas. By applying the dual-reflector shaping technique to the CPFRA antennas, the reflection-phase distributions of the two reflecting surfaces comprising the CPFRA antennas are modified to realize low profile, high aperture efficiency, and arbitrary aperture-field distribution simultaneously. Numerical simulations based on the geometrical optics show that the aperture efficiency can be improved up to around 100% by realizing uniform aperture-field distribution and reducing the spillover. Designs of CPFRA antennas with low sidelobe levels are also presented.