3D-SAR Processing of UAV-mounted GPR Measurements: Dealing with Non-Uniform Sampling

This contribution is devoted to analyze the effect caused by non-uniform sampling and to present a technique for dealing with this issue in a system composed by a Ground Penetrating Radar (GPR) mounted on board an Unmanned Aerial Vehicle (UAV). Radar measurements are accurately geo-referred in order to enable the use of Synthetic Aperture Radar (SAR) techniques. The adopted SAR technique must be able to handle measurements gathered at arbitrary positions. In addition, the positioning data must be also carefully processed to cope with non-uniform sampling and flight deviation issues. A method based on defining a set of conditions that a measurement position must satisfy to be selected for processing has been proposed. Comparing the resulting 3D radar images retrieved from measurements gathered during autonomous flights, both the image artifacts and the computational time are significantly decreased, showing the feasibility of the proposed technique to overcome non-uniform sampling issues.