Multibeam Radar Altimetry: Spaceborne Feasibility and Airborne Experimentation.

摘要

This report summarizes the results of an investigation into the technical feasibility of multibeam altimetry. Three candidate sensor concepts are considered: a real-aperture system with an appropriate 4.5-m antenna for operation at 13.5 GHz or a 1.8-m antenna for operation at 36 GHz; a 13.5 GHz interferometer system; and a 13.5 GHz synthetic aperture system. The overall findings show a preference for the real-aperture system, with a trade-off between the larger antenna required at 13.5 GHz and rain attenuation effects at 36 GHz. Both systems are shown to be capable of providing equal to or less than 5 cm height resolution and an approx. 19 km along-track spatial-wavelength resolution for the beam that is pointed 50 km off-nadir in the cross-track direction. An experimental aircraft program is also discussed. The objective is to provide experimental verification of these theoretical findings. (rrh)