Development of a semi-empirical polarimetric scattering model for microwave radar observations from bare soil surfaces

A semi-empirical polarimetric scattering model for microwave radar observations from bare soil surfaces was developed using polarimetric radar measurements and the knowledge based on the theoretical and numerical solutions. At first the angular and spectral dependencies of the measured radar backscatter for a wide range of roughness and moisture conditions are examined. Then, the measured scattering behavior was tested using theoretical and numerical solutions. Based on the experimental observations and the theoretical and numerical solutions, a semi-empirical model was developed for the backscattering coefficients in terms- of the surface roughness parameters (rms height and autocorrelation length) and the relative dielectric constant of the soil surface. The polarimetric model was found to yield very good agreement with the backscattering measurements of this study as well as with independent measurements. The semi-empirical polarimetric scattering model was also compared with other available scattering models