Spaceborne GNSS-R from the SMAP mission: First assessment of polarimetric scatterometry

NASA's Soil Moisture Active Passive (SMAP) mission has been tuned to perform a Global Navigation Satellite Systems Reflectometry (GNSS-R) experiment. The motivation of this study is to assess the capabilities of GNSS-R for soil moisture determination, biomass monitoring and cryosphere studies. The use for first time of the Polarimetric Ratio (PR) from a spaceborne platform shows significant sensitivity to soil moisture. Additionally, the investigation for first time of the leading and trailing edges width sensitivity to Above Ground Biomass (AGB) and rough topography shows promising results. Better understanding of these effects in the reflected waveforms will improve the development of retrieval algorithms.