Radar observations of strong subsurface scatterers. A model of backscattering

Backscattering from strong buried scatterers (like water and gas mains) are studied both experimentally and theoretically. The contrast coefficients are introduced as a quantitative characteristics of the relative contribution of subsurface strong reflector to backscattered signal against the background of scattering of air-soil interface. Even though the radar response from "ideal" subsurface body itself is negligibly small, scattering from roughness of air-soil boundary brings into existence (due to interference with specularly reflected from object field) the backscattered signal which depends on depth of the object and therefore may be used for its detection. Contrast coefficients are calculated and the maximal depth of detection of subsurface metallic plate is estimated for different types of soil (sand, clay), and for different polarizations and frequencies of radar signal.