Performance of an ultra wide band UHF antenna

A 4:1 bandwidth UHF antenna has been developed for radar applications. The small array could be mounted at the belly of an airborne platform. The antenna and the feed network were designed to fit in a shallow radome (50 cm/spl times/100 cm/spl times/100 cm). The depth of the radome is only one quarter of a wavelength at the low end of the UHF band. The small volume imposes a severe constraint in the electrical and mechanical design of the antenna. The antenna produces a broad beam in the elevation (EL) plane, with its beam peak pointed at the 30-degree depression angle (60 degree from the nadir).