ROUGH SOIL SURFACE SCATTERING AND EMISSION MODELING: A COMPREHENSIVE REAPPRAISAL OF THE AIEM MODEL BY USING NUMERICAL AND EXPERIMENTAL DATA

This paper presents a comprehensive reappraisal of the scattering, both backscattering and bistatic scattering, and emission of rough soil surface predicted by a well established theoretical model, the advanced integral equation model (AIEM). Extensive numerical data simulated by approximate and numerically exact models as well as experimental datasets of well characterized bare soil surfaces were used to evaluate the performance of AIEM in predicting the scattering coefficient and microwave emissivity over a wide range of geometric parameters and ground surface conditions. The results show that AIEM predictions are generally in good consistency with both of numerical simulations and experiment measurements in terms of angular, frequency and polarization dependences, except for some deviations in a few cases (e.g. at large incident angles and dry soil conditions). Possible explanations for the discrepancy between model prediction and data are given, together with suggestions for model usage and refinements.