Design of a dual-frequency, dual-polarized, high power millimeter wave radar antenna

The Remote Sensing Laboratory at the University of Massachusetts wished to combine two millimeter-wave polarimetric radars operating at 33 and 95 GHz into a single unit. To accomplish this a single antenna was developed which could accommodate both radars simultaneously. At the heart of this design was the development of a single compact feed which operates dual-polarized at each of the two desired frequencies with high polarization purity. This feed illuminates a 1-meter-diameter dielectric lens with f/d=1.8. To provide a more compact design, a planar splash plate 55 cm in diameter is included in the optical path. The feed is pressurized with SF/sub 6/ to provide power handling capability up to 125 kW peak at 33 GHz and is therefore pressure-sealed throughout.<>