3D nonlinear electromagnetic inversion for buried objects in layered media

Electromagnetic (EM) inverse scattering in ground penetrating radar (GPR) is complicated and doubly challenging: one is that EM wave propagation is essentially a 3D wave phenomena and waves interact in a complex way with ground surface, subsurface layers, and objects; the other is that this class of nonlinear and ill-posed inverse problem involves intensive computation. In the practical use of GPR, the shallow earth may be necessarily modeled by one or more overburden layers. Thus, it is necessary to extend the existing inverse scattering methods developed for a homogeneous background or half-space to a multilayered medium. In this regard, here we deal with such a 3D EM nonlinear inverse scattering problem in multilayered media as a new step toward 3D image reconstruction of buried objects.