The Study of Soil Moisture Retrieval Algorithm from GNSS-R

The L1 band (1.58 GHz)on board GPS satellite is very suitable for monitoring the change of soil moisture. The research for retrieval of soil moisture from GNSS-R is just beginning. This paper makes an analysis by using simulation data from AIEM model and experiment data from SMEX02. The analysis for simulation data from AIEM model shows that scattering signal of GPS is influenced much by angle and roughness, so the retrieval algorithm should consider the angle and roughness. The analysis of experiment data in SMEX02 indicates that the average correlation coefficient is above 0.85 between soil moisture and GNSS-R SNR for a single field site, so the soil moisture can be accurately retrieved by GNSS-R for single site, and the retrieval algorithm should be built for single site under considering incidence angle.