Persistent Scatterometry from Geostationary Orbit using Smallsats with MIMO Beamforming

A geostationary orbit (GEO)-based radar scatterometer concept is presented here that offers the capability to monitor sea state over surveillance sectors with extended persistence and over a very wide area. Despite the long ranges from GEO, the resolution on the ocean surface can be preserved by employing a configuration of spread-out small satellites (smallsats) using microwave transmitters at moderate power levels. The physical smallsats are kept to a practical number by the use of multiple-input multiple-output (MIMO) beamforming that forms a virtual aperture. As illustrated herein, practical configurations appear to be realizable. Unlike traditional spaceborne radar scatterometers, the concept permits extended and uninterrupted surveillance of selected ocean sectors.