Full Polarimetric GNSS-R Sensitivity Assessment of Ocean Roughness

The sensitivity of Global Navigation Satellite System Reflectometry (GNSS-R) to ocean surface roughness is well-established within the scientific and technological communities. Missions like the CYclone GNSS (CYGNSS) have been specifically designed to detect and monitor hurricanes and other oceanic storms. In addition, data from the Soil Moisture Active Passive (SMAP) mission’s radar, operating in receive mode, known as SMAP -Reflectometer or SMAP-R, provide opportunities to evaluate the polarimetric sensitivities of GNSS-R measurements to ocean surface roughness. This enables exploration of potential applications that can be achieved or enhanced through the use of polarimetric techniques. This study provides a sensitivity analysis of wind-driven changes in surface roughness using a comprehensive view of full-polarization GNSS-R signals over the ocean. The results show an improvement of about 0.6% on ocean wind speed retrievals for dual-polarization GNSS-R missions with respect to single-polarization GNSS-R missions. The results show an improvement of about 4.5% on ocean wind speed retrievals for full-polarization GNSS-R missions with respect to single-polarization GNSS-R missions.