Numerical Study of the Scattering of a Short-Pulse Plane Wave by a Buried Sphere in a Lossy Medium

F. Frezza[1], F. Mangini[1], M. Muzi[2], P. Nocito[3], E. Stoja[1], N. Tedeschi[1]
[1]Department of Information Engineering, Electronics and Telecommunications, "La Sapienza" University of Rome, Rome, Italy
[2]Institute of Advanced Biomedical Imaging, "G. d'Annuzio" University Fondation, University "G. d'Annuzio" Chieti-Pescara, Chieti, Italy
[3]Istituto Superiore C.T.I., Communications Department, Ministry of Economic Development, Rome, Italy

The scattering by a buried sphere in the frequency domain with the use of the Finite Element Method (FEM) implemented by COMSOL Multiphysics, is analyzed. A short-pulse is used as an excitation with the spectrum spanning from 50 MHz to 1 GHz. In order to validate our results, a comparison with data available in the literature is presented, in the simple case of a perfectly-conducting (PEC) sphere. Afterwards, to gain insight on the role of the sphere radius and the distance of the buried sphere from the interface, other simulations are performed. The case of a dielectric sphere, instead of the perfectly-conducting one, is studied too.