Is it possible to retrieve the complex permittivities using double bounce?

International audienceThe monitoring of urban areas (bridges, roads, dams, etc.) raises interest for permittivity estimation, in particular for failure detection. Radar sensors - ground or airborne-based - can offer solution for remote monitoring. This kind of environment can be characterized by double bounces scattering mechanism. Several methods have been developed for the case of a specular reflection using the Fresnel coefficients. In this paper, we recall these methods and propose a numerical solution to retrieve complex permittivities using double-bounces