Ku-band circularly-polarized omni-directional monopole antenna based on metamaterial polarizers

This paper introduces a circularly polarized omni-directional antenna, which is composed of a monopole antenna and 6 patches of metamaterial polarizers. Each metamaterial polarizer includes three closely spaced metallic wires printed on a dielectric substrate. The metamaterial polarizer is used to transform the antenna radiation from linear polarization into circular polarization. Axial ratio (AR) below 4.2 dB is obtained for elevation angle from 10° to 52° within the frequency band from 12.25 GHz to 12.75 GHz, which covers the receiving Ku-band for satellite communication. A prototype is fabricated and measured. The measured result verifies the antenna design.