Characterization of volume scattering of dry sand at millimeter-wave frequencies

Fully polarimetric measurements of volume scattering contribution from dry layer of fine sand with smooth air/sand interface were performed at millimeter-wave frequencies. The measured radar response was compared to predictions made by the numerical solution of the DMRT model. Sand particles were modeled as spherical particles. The simulated response was able to predict the angular dependence of the data but was not able to predict accurately the absolute level, especially for the cross-polarized return. Furthermore, a simpler model, which was developed earlier for asphalt surfaces and is based on 1^st order solution of RT for semi-infinite medium, was tested against the measured data. The model was not able to predict the angular dependence demonstrated by the measured data.