20/30 GHz dual-band circularly polarized reflectarray antenna based on the concentric dual split-loop element

摘要

A concentric dual split-loop element is designed and investigated for reflectarray antenna design in the emerging 20 GHz and 30 GHz Ka-band satellite communication spectrum. The element is capable of providing adjustment of the phase of reflection coefficients for circular plane waves in two separate frequency bands, by rotation of the individual split-loops. Cross-polar reflection is simultaneously minimized by optimizing the gaps in the split-loops. Based on the element characteristics, an iterative design procedure is proposed and used to design a front-fed reflectarray antenna. The aperture efficiencyexceeds 56% with an on-axis axial ratio below 0:21 dB in both frequency bands.