Simulating Commercial GPR antennas: How close can we get?

This paper presents three-dimensional (3D) numerical models of commercially used Ground-Penetrating Radar (GPR) antennas from Mala Geoscience and Geophysical Survey Systems, Inc. (GSSI). GprMax, an electromagnetic simulator based on the Finite-Difference Time-Domain (FDTD) technique, is used along with ParaView (an open-source visualisation application) to create, visualise and validate the models. Comparisons of modelled and real A-scans of antenna free-space responses (crosstalk) have shown good agreement, and further validation using experimental data from buried pipes has corroborated these findings. Accurate antenna models of real GPR antennas allow the direct comparison of modelled and real GPR signals, providing an investigative tool for future research in areas such as material property and geometry information from GPR wavelets, and optimisation of antenna designs.