Assessment of a micro-UAV system for microwave tomography radar imaging

Micro-Unmanned Aerial Vehicles (UAVs) are flexible observation platforms suitable to cover inaccessible areas on demand. Accordingly, huge attention is deserved towards development of miniaturized sensing technologies compliant with UAV payload constrains and capable of providing high-resolution images of the region under test. As a contribution to this topic, the paper presents a prototype UAV system for radar imaging made by a commercial micro-UAV equipped with a miniaturized low power radar, whose imaging capabilities are enhanced by a properly designed data processing strategy. Such a strategy involves a processing step performed in time domain, which accounts for a procedure devoted to compensate flight altitude variation and a Singular Value Decomposition (SVD) based noise filtering approach. After, the focused images of the surveyed scenario are obtained by using a microwave tomographic approach, which integrates data about UAV position and faces the imaging as a linear inverse scattering problem. A feasibility experiment, carried out to test the operational mode of the assembled system, is presented. The obtained results corroborate that the integration of GPS and flight altitude information into the microwave tomography approach allows valuable radar imaging capabilities in terms of target localization accuracy.