Non-destructive surveys via microwave tomography enhanced multichannel GPR

Non-destructive technologies (NDTs) turn out to be of paramount importance to gain knowledge about the subsoil and built environments and Ground Penetrating Radar (GPR) is widely exploited since it allows for performing an effective subsurface imaging [1]. Accordingly, huge attention has been given to the development of multichannel GPR systems suitable to speed up the measurement phase and increase the amount of collected data [2], [3]. Thanks to the technological advance, the collection of multiview/multistatic/multifrequency data is now possible opening the way to the development of data processing strategies capable of exploiting the increased amount of information and enhancing the imaging performance. This communication deals with a data processing strategy based on microwave tomography [4], [5] specifically designed to handle multi-view and multi-static GPR data. In a first stage, a data pre-processing suited for the multiview/multistatic configuration is performed in the time domain. After, the imaging is formulated as the solution of a linear inverse scattering problem in the 2D scalar case. The data processing strategy will be described in detail at the conference and results of numerical tests based on full-wave synthetic data will be shown to assess its effectiveness.   [1] Lai, Wallace Wai-Lok, Xavier Derobert, and Peter Annan. "A review of Ground Penetrating Radar application in civil engineering: A 30-year journey from Locating and Testing to Imaging and Diagnosis." Ndt & E International 96 (2018): 58-78. [2] Kaufmann, Manuela Sarah, et al. "Simultaneous multichannel multi‐offset ground‐penetrating radar measurements for soil characterization." Vadose zone journal 19.1 (2020): e20017. [3] Trinks, Immo, et al. "Large‐area high‐resolution ground‐penetrating radar measurements for archaeological prospection." Archaeological Prospection 25.3 (2018): 171-195. [4] Catapano, Ilaria et al., “Ground‐Penetrating Radar: Operation Principle and Data Processing,” Wiley Encyclopedia of Electrical and Electronics Engineering: 1-23. [5] Persico, Raffaele, Romeo Bernini, and Francesco Soldovieri. "The role of the measurement configuration in inverse scattering from buried objects under the Born approximation." IEEE transactions on antennas and propagation 53.6 (2005): 1875-1887.   Acknowledgements: The communication has been funded by EU - Next Generation EU Mission 4 “Education and Research” - Component 2: “From research to business” - Investment 3.1: “Fund for the realisation of an integrated system of research and innovation infrastructures” - Project IR0000032 – ITINERIS - Italian Integrated Environmental Research Infrastructures System - CUP B53C22002150006. The authors acknowledge the Research Infrastructures participating in the ITINERIS project with their Italian nodes: ACTRIS, ANAEE, ATLaS, CeTRA, DANUBIUS, DISSCO, e-LTER, ECORD, EMPHASIS, EMSO, EUFAR ,Euro-Argo, EuroFleets, Geoscience, IBISBA, ICOS, JERICO, LIFEWATCH, LNS, N/R Laura Bassi, SIOS, SMINO.