Experimental Assessment of a Novel Hybrid Scheme for Quantitative GPR Imaging

A hybrid inversion procedure for subsoil prospecting by ground-penetrating radar (GPR) measurements is proposed and experimentally validated in this letter. The approach integrates the benefits of qualitative beamforming in an adaptive multifrequency (MF) inexact-Newton scheme formulated in Lebesgue spaces with variable exponents. After a first preprocessing step aimed at estimating the incident field, a delay-and-sum (DAS) method provides an initial image of the region of interest. Then, the inexact-Newton algorithm exploits the qualitative indicator for both setting the exponent function and selectively weighting the update of the unknown during iterations. The proposed approach is tested against experimental GPR data.