GNSS-Reflectometry Activities on the DoT-1 Microsatellite in Preparation for the Hydrognss Mission

GNSS Reflectometry has been developing rapidly as an L-Band remote sensing technology suitable for small satellites and continues to find applications over ocean, ice and land. The TDS-1 [1] and CYGNSS missions [2] were primarily flown to target wind speed over the ocean but subsequently enabled demonstration of the potential for cryospheric and hydrological applications. The proposed HydroGNSS ESA Scout mission concept [3] has been developed to address land-based hydrological essential climate variables, specifically soil moisture, inundation, freeze / thaw state and biomass, as required by GCOS [4]. New techniques anticipated for HydroGNSS include the use of Galileo signals, coherent reflection sensing, dual polarisation and dual frequency reflectometry exploration.