Single-Element Zoom Antenna

This proposal describes a microwave radiating element that incorporates a variable beamwidth (ZOOM) capability. The element generates a virtual aperture that is equivalent to a conventional aperture of 10's of wavelengths. This element is appropriate tospace-based applications. It offers not only a low per unit cost, but its relaxed satellite requirements (low prime power, no computer requirements, moments of inertia consistent with reduced satellite corrections, small physical size provides lessblockage of solar panels, and other antennas) result in further lowering the system-level deployment costs. It is further proposed that an excellent application for this antenna would be the satellite-based GPS transmitter on the new GPS-III program. ThePhase I SBIR will complete the final design of the antenna for the GPS mission, including the projected performance and a set of shop drawings. The Phase II SBIR will fabricate, test, and demonstrate this antenna system. The proposed variable beamwidth,ultra-high resolution antenna will provide greatly improved earth-sensing from space, at a very low cost. This has both military and commercial applications, including: earth resource location, ground mapping, high resolution imaging, etc. The low costof this antenna, along with its attendant reduction in satellite resources, will be very attractive for commercial interests.