HR: 0800h
AN: G51C-0861    [Abstracts]
TI: Phase Sensitiveness to Soil Moisture in Controlled Anechoic Chamber: Measurements and First Results
AU: * Ben Khadhra, K
EM: kais.benkhadhra@dlr.de
AF: DLR )German Aerospace Center, - Microwaves and Radar Institute, Oberpfaffenhofen, D-82234 Wessling, Germany, Wessling, 82234 Germany
AU: * Ben Khadhra, K
EM: kais.benkhadhra@dlr.de
AF: Technische Universt„t Chemnitz, Elektrotechnik und Informationstechnik, Technische Universt„t Chemnitz, Elektrotechnik und Informationstechnik, Reichenhainer Strasse 70, D-09107 Chemnitz, Germany, Chemnitz, 09107 Germany
AU: Nolan, M
EM: matt.nolan@uaf.edu
AF: Institute of Northern Engineering, University of Alaska Fairbanks, nstitute of Northern Engineering 455 Duckering Bldg, University of Alaska Fairbanks Fairbanks, AK 99775-5860, Fairbanks, 99775-5860 United States
AU: Hounam, D
EM: david.hounamdlr.@dlr.de
AF: DLR )German Aerospace Center, - Microwaves and Radar Institute, Oberpfaffenhofen, D-82234 Wessling, Germany, Wessling, 82234 Germany
AU: Boerner, T
EM: thomas.boerner@dlr.de
AF: DLR )German Aerospace Center, - Microwaves and Radar Institute, Oberpfaffenhofen, D-82234 Wessling, Germany, Wessling, 82234 Germany
AB: To date many radar methods and models have been reported for the estimation of soil moisture, such as the Oh-model or the Dubois model. Those models, which use only the magnitude of the backscattered signal, show results with 5 to 10 % accuracy. In the last two decades SAR Interferometry (InSAR) and differential InSAR (DInSAR), which uses the phase of the backscattered signal, has been shown to be a useful tool for the creation of Digital Elevation Models (DEMs), and temporal changes due to earthquakes, subsidence, and other ground motions. Nolan (2003) also suggested the possibility to use DINSAR penetration depth as a proxy to estimate the soil moisture. The principal is based on the relationship between the penetration depth and the permittivity, which varies as a function of soil moisture. In this paper we will present new interferometric X-band laboratory measurements, which have been carried out in the Bistatic Measurement Facility at the DLR Oberpfaffenhofen, Microwaves and Radar Institute in Germany. The bistatic geometry enables us to have interferometric pairs with different baseline and different soil moistures controlled by a TDR (Time Domain Reflectivity) system. After calibration of the measuring system using a large metal plate, the sensitivity of phase and reflectivity with regard to moisture variation and therefore the penetration depth was evaluated. The effect of the surface roughness has been also reported. Current results demonstrate a non-linear relationship between the signal phase and the soil moisture, as expected, confirming the possibility of using DInSAR to measure variations in soil moisture.
DE: 1866 Soil moisture
SC: Geodesy [G]
MN: Fall Meeting 2005