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First Results from ERS Tandem Insar Processing on Svalbard

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Abstract

This paper describes some results from a work on how INSAR tandem data can be utilized with the EETF SAR processor combined with the GEOSAT orbit determination program. It is demonstrated how an interferogram simulator can be used to detect errors in existing DEM's and how fringes caused by the terrain can be subtracted from the real interferogram. For the first time it has been possible to monitor motion of the lower part of the fast moving glacier Kronebreen with INSAR due to 1 day interval between the two SAR images. A DEM computed from interferograms (INSAR DEM) over Svalbard is assessed using the existing NP DEM. The precise orbit determination makes the fringes follow the coastline very well over parts of the scene, however, uncertainties in the baseline estimation may cause systematic errors in the INSAR DEM over larger areas in the azimuth direction.
1997ESASP.406..337E
1997ESASP.406..337E
1997ESASP.406..337E
1997ESASP.406..337E
1997ESASP.406..337E
1997ESASP.406..337E
1997ESASP.406..337E
1997ESASP.406..337E
... From the literature, it could be found that visual appearance of the fringes is widely used to indicate the quality of interferogram (Eldhuset, et al., 1996;Zou, et al., 2002). That is, clear fringes mean good quality of an interferogram. ...
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... A number of parameters can be used to measure the quality of an interferogram, such as the visual appearance of the fringes (Eldhuset et al., 1996;Zou et al., 2002) and the histogram of coherence of the interferometric SAR (Guarnieri and Prati, 1997;Gens, 1998). All of these methods have their shortcomings. ...
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... As part of the ESA AO-Tandem project no. 301 carried out at FFI, 18 pairs of ERS Tandem SAR raw data from descending satellite pass over Svalbard were ordered from ESA/ESRIN [7]. SAR raw data tapes were received from German and U.K. processing and archiving facilities. ...
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