Phase-ramp reduction in interseismic interferograms from pixel-offsets
Type
ArticleAuthors
Wang, Teng
Jonsson, Sigurjon

KAUST Department
Crustal Deformation and InSAR GroupEarth Science and Engineering Program
Environmental Science and Engineering Program
Physical Science and Engineering (PSE) Division
Date
2014-05Permanent link to this record
http://hdl.handle.net/10754/563532
Metadata
Show full item recordAbstract
Interferometric synthetic aperture radar (InSAR) is increasingly used to measure interseismic deformation. Inaccurate satellite-orbit information, expressed as phase ramps across interseismic interferograms, is believed to be one of the main sources of error in such measurements. However, many interferograms exhibit higher phase gradients than expected from the reported orbital accuracy, suggesting that there are other error sources. Here, we show that interferogram phase ramps are in part caused by uncorrected satellite timing-parameter errors. We propose a two-step approach to reduce the phase ramps using pixel-offsets estimated between SAR amplitude images. The first step involves using a digital elevation model (DEM) to estimate absolute timing-parameter errors for the reference image of the SAR dataset and the second step updates the timing parameters of the master image for each interferogram. We demonstrate a clear ramp reduction on interseismic interferograms covering the North Anatolian Fault in eastern Turkey. The resulting interferograms show clear signs of interseismic deformation even before stacking. © 2014 IEEE.Citation
Wang, T., & Jonsson, S. (2014). Phase-Ramp Reduction in Interseismic Interferograms From Pixel-Offsets. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 7(5), 1709–1718. doi:10.1109/jstars.2014.2298977Sponsors
The Envisat data used in this paper were provided by the European Space Agency (ESA) through category-1 project 6703. We thank three anonymous reviewers for their helpful comments.ae974a485f413a2113503eed53cd6c53
10.1109/JSTARS.2014.2298977