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Unmanned Aerial Vehicle-Based Ground-Penetrating Radar Systems: A review

Advances in unmanned aerial vehicle (UAV) technology have fostered its use in a wide range of areas, such as agriculture and forestry, surveillance and security, and infrastructure inspection. One of the advantages of UAVs is their ability to conduct remote inspection and sensing by placing different kinds of sensors on board them. In this sense, UAV-based ground-penetrating radar (GPR) systems are of particular interest as they bring together the advantages of UAVs and GPR, resulting in contactless subsurface sensing and imaging systems capable of performing a fast scanning of difficult-to-access scenarios. This contribution reviews the advances on UAV-based GPR systems, describing their architecture and subsystems. In particular, an analysis of different UAV-based GPR systems is presented, focusing on the technical solutions adopted in each case and the detection capabilities that have been achieved. Attention will be also given to the methodologies implemented to obtain 3D high-resolution images of the underground. Finally, the main challenges faced by these systems concerning further improvements of the scanning throughput and the detection accuracy will be discussed.