HF IMAGING TECHNIQUES FOR GROUND PENETRATION (TOMOGRAPHIC PROCESSING FOR AIRBORNE REMOTE SENSING OF UNDERGROUND ENVIRONMENTS)

The proposal investigates high frequency (HF) band surveillance to provide a new capability for locating tactical targets in deep hide (buried, camouflaged, etc.), and for detection of underground barrels, drums, pipes, tunnels, and underground stream beds for environmental surveys and waste site remediation activities. HF imaging has the potential to locate and identify features much deeper than current ground penetration radars. Commercial applications such as locating avalanche victims or others buried under snow packs and foliage are deemed feasible at HF. Bistatic and multistatic tomographic image processing techniques and algorithms at HF frequencies form the basis of the proposed imaging concept. The baseline bistatic/multistatic surveillance system will exploit illuminations from either LOS or OTH transmitters coupled with receivers on a small aircraft to detect buried targets by forming tomographic images of the target returns. Imaging at multiple frequencies and polarization diversity will be studied to identify targets on the surface and at various depths. lssues will be investigated including waveforms, antennas, receivers, processing and advanccd navigation systems/auto focusing techniques. The design of an airborne test system, including data collection and processing sub-systems will be performed. Consideration will be given to implementation on the AMBIS testbed during the phase 1 option.