Results of a remote sensing experiment using a low frequency ultra-wideband SAR to investigate the phenomenology of landmines

The Army Research Laboratory (ARL) has developed a low frequency, ultra-wideband, (UWB) synthetic aperture radar (SAR) based on impulse technology to explore foliage penetration (FOPEN) and ground penetrating radar (GPR) phenomenology. The radar has a bandwidth of 1 GHz and center frequency of 550 MHz, and is mounted on a boom-lift that can operate at heights of 5 to 45 meters while moving at 1 kilometer per hour allowing the radar to operate in a strip-map SAR mode. A GPR data collection was held at a prepared site at Yuma Proving Ground, Arizona using the ARL SAR in January 1996. A thorough geophysical characterization was conducted of the site using an EM-31, a GSSI SIR-3 with 150, 300, and 500 MHz antennas, as well as over 25 test pits. Data was collected with the boom-SAR at depression angles ranging from 10 to 45 degrees and aspect angles of up to 100 degrees. This paper will concentrate on an area of the site containing over 80 surface, flush, and 6 inch buried inert landmines, and covers target RCS vs. depression angle as well as the frequency dependence of the target scattering.