## 1 Introduction
### State of the Art
This integrated approach was beneficial for delineating the spatial arrangement of buried remains, characterizing the geometry of anthropogenic settlements, and obtaining detailed insights into various building materials' composition and manufacturing processes. An attempt was made to integrate the fluxgate gradiometer and electromagnetic induction methods with GPR in the prospection of Bronze Age circular ditches in the western part of Belgium [20]. It was shown that GPR allowed the detection of a concentric and a single monument, while the fluxgate gradiometer and electromagnetic induction methods were unsuccessful in revealing the ditches. A comprehensive study of the sedimentary conditions typical of archeological projects was performed in [5]. It was shown that GPR finds its most relevant applications in geoarchaeological contexts within fluvial, beach, and associated aeolian environments. These areas, rich in archaeological sites, prove ideal for various GPR methods. Caves pose more significant challenges due to being characterized by thick floor sequences of thin stratigraphic units, necessitating low-frequency antennae for depth penetration but at the cost of lower resolution. Promising prospects lie ahead for GPR in lakes, swamps, and bogs, offering good depth penetration despite potential difficulties in terms of access and collection. Urban environments present the most complexity due to anthropogenic stratigraphy, requiring detailed profile analysis in a closely spaced grid for interpretation, with amplitude slice-maps only understood at subsequent stages. Airborne ground-penetrating radar (GPR) is an advanced technology employing electromagnetic waves to delve into the subsurface and capture intricate geological data [21]. Unlike conventional ground-based GPR, drone-based GPR presents numerous advantages [22]. Equipped with GPR sensors, unmanned aerial vehicles (UAVs) can swiftly and non-invasively cover extensive areas, providing a comprehensive three- or even four-dimensional view of subsurface boundaries and their geotechnical characteristics, thus achieving enhanced spatial resolution [23]. Using real-time kinematic (RTK) GPS positioning facilitates the replication of precise survey paths [24]. It is incorporated with signal processing techniques like cross-correlation-based background subtraction and interference suppression, ensuring the accurate identification of subsurface targets [25; 26]. Drone-borne GPR enables the mapping of geotechnical properties such as the soil moisture [27] and field-scale soil electrical conductivity [28]. This technology proves invaluable in areas with limited accessibility, such as hill slopes prone to landslides or regions affected by colliery waste. [PERSON] et al. [29] effectively captured a significant 3D dataset using drone-borne controlled-source electromagnetic (CSEM) systems over alpine glaciers, demonstrating the feasibility of obtaining detailed imagery of the immediate subsurface in challenging terrains. The utility of drone-mounted GPR in guiding and optimizing mining operations is showcased in [30]. By mounting two 120 MHz GPR antennas (RADarteCAM SWEDEN AB, Boden, Sweden) on a drone, they successfully mapped the structural discontinuities within local geological materials in a quarry excavation area in Falconara Albanese, Italy. This application underscores the adaptability of drone-based GPR for specific geological investigations. [PERSON] et al. [31] conducted experiments in challenging clay soils, identifying characteristic features in the upper subsurface environment using airborne GPR. However, they acknowledges the challenges of employing GPR in clayey soil, where electromagnetic waves rapidly decay [32]. Nonetheless, this challenge is surmountable, as [PERSON] et al. [33] demonstrated in their use of land-based GPR for mapping disturbed clayey layers in agricultural fields. Nevertheless, employing GPR in clay-rich soils, where electromagnetic waves dissipate rapidly, poses a considerable challenge [33; 34].