Airborne Underground Imaging-Radar System Definition

A Phase I study is proposed to investigate the feasibility of applying a novel ray-tracing technique for electromagnetic propagation through the dense, refractive media of the earth's upper surface. Application of the technique to modern radar and navigation technology should result in the ability to conduct airborne surveillance of subsurface targets with three dimensional spatial resolution of less than a meter. The primary project objective is to develop a high-resolution, airborne ground-penetration radar (GPR) system concept incorporating three-dimensional synthetic aperture radar (SAR) imaging techniques; wideband waveforms; and Global Positioning System (GPS) navigation. The work effort will (1) evaluate the refractive-media ray-tracing technique; (2) produce preliminary refractive- SAR (RSAR) architecture that merges time- and frequency-domain information to fill three-dimensional grid cells; (3) define a wideband, low-frequency (100 dB) radar receiver for GPR applications; and (4) collect a sample set for chirped-waveform radar data in a refractive medium to validate the RSAR concept. From a military perspective, this radar technique has the potential to produce subterranean images applicable to defense-related surveillance of mine fields, buried assets, bunkers, and tunnels. Anticipated Benefits/Potential Applications - Ariticipat I Defense applications include detection of near-surface mines, detection and identification of buried assets, tunnel and bunker imaging, and civil engineering aspects of military logistics. Commercial applications include mineral prospecting; water percolation surveys; EPA-required waste site monitoring; subsurface pollution investigations; mapping of buried pipelines; surveys of conductivity, thermal, porosity, and moisture content; FEMA-related emergency response for large-scale flood-monitoring.