A novel dual-band and dual circular-polarization feed for paraboloidal reflector antenna

A new feed technology with dual-band and dual circular polarization capability in a shared aperture featuring constant phase center, high efficiency and so on is presented. The radiations of the proposed feed are nested with circular wave-guide and metallic annular ring, which operates in X-band and LS-band, respectively. The upper band feed system consists of a orthomode transducer (OMT) and a circular wave-guide phase-shifter with metal posts besides the radiation circular wave-guide, and the LS-band feed system is formed by the annular ring radiation patch fed by arc patches combining with the -3dB microstrip hybrid and the “anti-phase & dual-feed” technique. Design consideration, simulation and measurements of the constructed feed system are presented and discussed.