Dielectric-loaded horn feeds for radiometer antenna

Abstract

The authors have developed a low-loss high-quality dielectric material that can be used in space antennas. A 7.5 degrees semi-flare angle dielectric-loaded horn is shown. The dielectric material is placed against the thin-wall metal cone of the horn and a thin layer of Left Koweld glue is used in the gap. Experimental E- and H-plane patterns of the horn antenna at 15.3 GHz are shown. The peak cross-polarization level is better than -40 dB at 6.84, 10.68, 18.7, 23.8, 36.5, and 90 GHz. Computed copolar footprints of a typical radiometer antenna using the dielectric-loaded horn feed are shown.<>