Analysis on Soil Moisture Estimation of SAR Data Based on Coherent Scattering Model

Abstract:
In this paper we propose a method for soil moisture inversion using phase information of SAR data, which is expected to be applied in the drought monitoring of soil water content using multi-temporal SAR data. It is developed from the coherent scattering model, which is first studied for random oriented volume over ground scattering in vegetated areas. Compared to the conventional water content estimation methods employing amplitude information of SAR data, no matter theoretical or empirical, the methods making use of phase information has its particular advantages. This proposed method based on scattering model is further promising in its capability to analyse the influences and sensitivity of the system parameters on the soil moisture inversion. Simulations are presented to show the range of soil moisture changes that can be inverted under the different conditions of system phase accuracy. Moreover, relevant experiment in the anechoic chamber was implemented. Good agreement is achieved between the model and the measurement.