Electromagnetic inversion in monostatic ground penetrating radar: TEM horn calibration and application

A comprehensive analysis of electromagnetic (EM) inversion applied to pavement profiling by using a monostatic ground penetrating radar (GPR) is presented. Since in GPR systems using transfers EM (TEM) horns, the antenna is positioned close to the the investigated medium and a strong EM interaction occurs. This effect is taken into account by modeling the antenna with equivalent sources placed on the aperture section and by using an accurate EM modeling within the inversion loop in order to account for the contribution of near-field effects. Experimental results on the antenna modeling procedure and on a pavement profile estimation validate the feasibility of both the calibration and the inverse problem proposed.