Concept Study of a 35-m Spherical Reflector System for NEXRAD in Space Application

Abstract

NASA, under the Earth Science Technology Program, is currently developing a novel instrument concept with associated antenna technologies for a space-based 35-meter diameter, Ka-band (35-GHz) Doppler, radar for monitoring hurricanes, cyclones and severe storms from a geostationary orbit. The objectives of the system under study are measuring hurricane precipitation intensity (quantitative rainfall rate), dynamics, and life cycle, thus providing temporal information critical for creating advanced warning systems and improving numerical model prediction of track, intensity, rain rate, and hurricane-induced floods. The practical benefits derived from this kind of space system such as enhanced public safety, better emergency response and mitigation of property loss and economic impacts are evidently clear. However, space-based antenna system of this size and of this bandwidth capability is not attainable as a single-launch system with today's deployable structural technology. The concept study work presented here includes concept trades and analysis, and discussions on the challenges associated with designing, analyzing, fabricating, and testing of this large antenna system, potential issues and problems, and recommendations for potential solutions.