A SHAPED SINGLE REFLECTOR OFFSET ANTENNA WITH LOW CROSS-POLARIZATION FED BY A LENS HORN

A novel compact primary-fed offset reflector antenna with the potentia l of radiating circular as well as elliptical beams with low cross-pol arization, is proposed. The reflector is fed by a horn with a phase-co rrecting lens in the aperture. Compared to the dual-reflector offset a ntenna, the concept is easier to assemble and mechanically more robust . The antenna has been synthesized and analyzed by computer programs r esulting from modifications of corresponding PO programs for dual-refl ector offset antennas. The synthesized antenna exhibits similar cross- polarization, side-lobe level, and aperture efficiency as those of dua l-reflector offset antennas, although the one-to-one correspondence be tween zero cross-polarization and conformal mapping from the feed to t he aperture, is not exactly valid for this approach.