A comparative assessment of information-exploitation techniques for GPR data inversion
Résumé
The inversion of Ground Penetrating Radar (GPR) data requires the development of
suitable information-exploitation techniques that are able to extract as much as possible
information on the unknown targets from the available measurements. An innovative singlefrequency
(SF) inversion technique based on a deterministic conjugate-gradient (CG)
minimization and the iterative multi-scaling approach (IMSA) is described. It is then shown
how to improve the performances of the SF-IMSA-CG method by the introduction of an
external frequency hopping (FH) iterative loop. On the one hand, the proposed FH-IMSA-CG
method allows to exploit the intrinsic frequency diversity of wideband GPR measurements
thanks to the FH strategy. On the other hand, the IMSA approach guarantees a significant
reduction of the problem unknowns, providing an increased resolution within the identified
regions of interest (RoIs). A numerical comparison shows the advantages of the FH-IMSA-CG
over its single-frequency version. Moreover, the benefits of integrating the IMSA within the
FH are verified by directly comparing the FH-IMSA-CG with its single-resolution (BARE)
version (FH-BARE-CG).