Microwave remote sensing of physically buried objects in the Negev Desert: implications for environmental research

• Published in: Remote sensing of environment Vol. 86; no. 2; pp. 243 - 256
• Main Authors: Daniels, Julian, Blumberg, Dan G., Vulfson, Leonid D., Kotlyar, Alex L., Freiliker, Valentin, Ronen, Gefen, Ben-Asher, Jiftah
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 30.07.2003; Elsevier Science
• Subjects: Applied geophysics; Earth sciences; Earth, ocean, space; Exact sciences and technology; Geomorphology; Hydrology; Internal geophysics; Modeling; Remote sensing; Structural geology; Wave propagation; Middle East; Israel; Negev; Hydrology; Wave propagation; Geomorphology; Structural geology; Modeling; Remote sensing; experimental studies; microwaves; altitude; models; detection; geomorphology; reflectors; absorption; remote sensing; aluminum; microwave methods; dielectric constant; electromagnetic methods; surface water; electromagnetic waves; sand; airborne methods; depth; propagation; Asia; radar methods
• ISSN: 0034-4257; 1879-0704
• DOI: 10.1016/S0034-4257(03)00111-1

We report remote detections of physically buried specularly reflecting objects using microwave radar at two sites: Ashalim and Tseelim in the northern region of the Negev Desert, Israel. These detections provide confirmation that microwave subsurface remote sensing is a genuine phenomenon. At Ashalim, a scatterometer operating in the P-band (441 MHz, 68 cm) was mounted on a cherry picker truck at a height of 8 m and used to detect two triangular aluminum mesh reflectors (forming a 1-m square area reflector) buried down to a depth of 8 cm in dry sand. At Tseelim, the same scatterometer was mounted on an airplane flying at an altitude of 70 m and used to detect 1-m square aluminum reflectors (each one submerged at a different location along the airplane flight path) buried down to a depth of 20 cm. The experimental results compare favorably with a theoretical model that incorporates radar absorption effects arising in the sandy subsurface layer and radar interference effects arising from phase differences between reflections from the surface and buried reflector. The theoretical modeling also predicts the detection of a subsurface reflector down to a depth of about 4.4 m. This experiment and the associated modeling approach is the first of a series of planned experiments, which we outline for the detection and the theoretical evaluation of buried reflectors using remote microwave and VHF radar. We identify potential subject areas for environmental research.