Multi-Frequency/Multi-Phase Center SAR Processing for Foliage Canopy and Surface Clutter Suppression

Period of Performance: 07/06/2000 - 08/16/2001


Phase 1 STTR

Recipient Firm

Technology Service Corp.
962 Wayne Avenue Array
Silver Spring, MD 20910
Principal Investigator

Research Institution

SRI International
333 Ravenswood Avenue Mail stop: 306-17
Menlo Park, CA 94025
Institution POC


Recent military conflicts demonstrate that critical targets hide from airborne sensors by deploying below the foliage canopy or in underground facilities. The use of multi-phase center antennas and frequency or polarization diversity in foliage penetration (FOPEN) and ground penetration (GPEN) radars may allow the suppression of the first scatterer return and enhance the detectability of these targets. These same techniques can improve the mapping of forested areas and detection of buried mines. During Phase I, the Technology Service Corporation / Stanford Research Institute team will develop innovative clutter cancellation algorithms including interferometric nulling and foliage height estimation techniques. TSC will also investigate the use of advanced methods such as its complex indicated angle technique that was recently extended to multiple sources and apertures. TSC will determine the theoretical algorithm performance using available SAR data and design evaluation simulation software. SRI will investigate 2-D and 3-D processing of its PENRAD-5 GPEN radar that recently collected data on buried mines at Yuma Proving Grounds. In Phase II, TSC will refine and optimize these techniques, and implement them as C/C++ modules to support more extensive evaluations using a combination of synthetic and measured UWB P-3 radar, FOLPEN-II and GeoSAR data. TSC and SRI will also apply the techniques to improve GPEN radar performance and extend it to targets at greater depths. The clutter suppression techniques to be developed on this effort have an immediate DoD application in locating military targets hidden either in foliage or underground facilities. Additional applications of this technology include improving the accuracy of topographical and Land Use/Land Cover mapping in forested areas, as well as the detection and improved location of buried objects such as pipes, electrical cables, utility lines, storage tanks, drums, unexploded ordnance, antipersonnel/antitank land mines, sink holes, grave sites and archaeological items. These techniques would also enhance search-and-rescue missions in forested areas, as well as commercial efforts to map cultural and natural features such as road networks, abandoned mines, illegal dump sites, earthquake fault lines, and water drainage patterns. These capabilities are of tremendous interest to commercial mapping, oil and mineral exploration industries, and state and federal government agencies.