Factors governing selection of operating frequency for subsurface- imaging synthetic-aperture radar

Conference · Fri Dec 31 04:00:00 EST 1993

OSTI ID:10134344

Brock, B C; Patitz, W E

A subsurface-imaging synthetic-aperture radar (SISAR) has potential for application in areas as diverse as non-proliferation programs for nuclear weapons to environmental monitoring. However, subsurface imaging is complicated by propagation loss in the soil and surface-clutter response. Both the loss and surface-clutter response depend on the operating frequency. This paper examines several factors which provide a basis for determining optimum frequencies and frequency ranges which will allow synthetic-aperture imaging of buried targets. No distinction can be made between objects at different heights when viewed with a conventional imaging radar (which uses a one-dimensional synthetic aperture), and the return from a buried object must compete with the return from the surface clutter. Thus, the signal-to-clutter ratio is an appropriate measure of performance for a SISAR. A parameter-based modeling approach is used to model the complex dielectric constant of the soil from measured data obtained from the literature. Theoretical random-surface scattering models, based on statistical solutions to Maxwell`s equations, are used to model the clutter. These models are combined to estimate the signal-to-clutter ratio for canonical targets buried in several soil configurations. Results indicate that the HF spectrum (3--30), although it could be used to detect certain targets under some conditions, has limited practical value for use with SISAR, while the upper VIHF through UHF spectrum ({approximately}100 MHz - 1 GHz) shows the most promise for a general purpose SISAR system. Recommendations are included for additional research.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 10134344
• Report Number(s): SAND--93-2010C; CONF-940449--2; ON: DE94008457; BR: GB0103012
• Country of Publication: United States
• Language: English

Related Subjects

350300
42 ENGINEERING
420200
54 ENVIRONMENTAL SCIENCES
540000
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
ARMS CONTROL
ATTENUATION
BACKSCATTERING
ENVIRONMENT
ENVIRONMENTAL SCIENCES
FACILITIES, EQUIPMENT, AND TECHNIQUES
FREQUENCY SELECTION
MONITORING
SOILS
SYNTHETIC-APERTURE RADAR
UNDERGROUND
VERIFICATION