Title :
Simultaneous Least Squares Adjustment of Multiframe Velocities Derived From Interferometric and Speckle-Tracking Methods
Author :
Liu, Hongxing ; Zhao, Zhiyuan ; Yu, Jaehyung ; Jezek, Ken
Author_Institution :
Dept. of Geogr., Texas A&M Univ., College Station, TX
fDate :
4/1/2008 12:00:00 AM
Abstract :
This letter extends the simultaneous least squares adjustment method to the calibration and merging of velocity measurements, which are obtained by applying interferometric and speckle-tracking methods to multiple frames of repeat-pass interferometric synthetic aperture radar (InSAR) data. The underlying observation equations have been derived for velocity control points and tie points. By exploiting a set of tie points, individual frames within a strip or a block can be correlated with each other, and the parameters of calibration models for all individual frames can be simultaneously determined. With Radarsat InSAR data over the Recovery Glacier, Antarctica, we demonstrate that our simultaneous least squares adjustment method has effectively removed velocity discontinuities between adjacent frames and greatly reduced the velocity-control-point requirement.
Keywords :
glaciology; hydrological techniques; least squares approximations; radar interferometry; remote sensing by radar; synthetic aperture radar; Antarctica; Radarsat InSAR data; Recovery Glacier; calibration models; interferometric method; interferometric synthetic aperture radar; least squares adjustment method; multiple frames; speckle-tracking method; velocity measurements; velocity-control-point requirement; Interferometric SAR (InSAR); least squares adjustment; phase unwrapping; speckle tracking; surface velocity;
Journal_Title :
Geoscience and Remote Sensing Letters, IEEE
DOI :
10.1109/LGRS.2008.915936