Air-launched and ground-coupled GPR data

Abstract

Ground penetrating radar (GPR) sees a wide range of applications; some investigations, such as assessment of roads and reinforced concrete bridge decks, often employ vehicle mounted GPRs. When mounted on vehicles, GPR can be deployed in an air-launched or ground-coupled form. The trade-offs in GPR performance are seldom discussed and not well understood for the two approaches of deployment. Further, what maximum height is acceptable for being ground-coupled and what is the minimum height to be considered air-launched? Our goal is to study the behaviour of direct air/ground and reflected waves as antennas are moved from being directly on ground to being in air (i.e., at a height off the air-ground interface, where the surface reflection is clearly isolated from the direct signal). We present both numerical simulation results and observed GPR data to study and characterize responses. Results confirm the generally observed behavior and provide insight into the trade-offs.