HR: 0800h
AN: G51B-0090    [Abstracts]
TI: Time Series Interferometry: Toward Weekly Observations
AU: * Bechor, N
EM: nbechor@stanford.edu
AF: Dept. of Geophysics, Stanford University, Mitchell Bldg, Stanford, CA 94305-2215 United States
AU: Zebker, H A
EM: zebker@stanford.edu
AF: Dept. of Geophysics, Stanford University, Mitchell Bldg, Stanford, CA 94305-2215 United States
AB: We present a method for using ScanSAR-SAR interferometry to obtain more frequent observations than is possible with current strip mode mapping. Envisat's repeat orbit time (35 days) and 5 ScanSAR sub-swaths can potentially generate weekly observations over very large areas, due to overlap between ScanSAR images. Our goal is to quantify slow deformation rates with a denser time series from a combination of Envisat's ASAR wide swath and image modes. We work on ScanSAR-SAR interferometry primarily because timing issues with the currently operating satellites prevent exploiting the full potential of direct ScanSAR-ScanSAR interferometry. However wide swath (ScanSAR) images have lower resolution than strip mode images, and eventual fringes have more speckle noise. For a resolution of 150 m, the speckle noise phase error can range from 0.65 rad to 1.4 rad, for terrain correlation values of 0.3 to 0.8 respectively. We simulate ScanSAR-SAR data processing with small "bursts" of ERS data (50 to 70 pulses) in accordance with Envisat's ScanSAR mode bursts, and process the bursts with a modified SPECAN algorithm [Lanari et al., 1998]. We find matching bursts by searching the strip mode image for a section whose Doppler frequency range matches the simulated ScanSAR burst Doppler frequencies. We evaluate the utility of the ScanSAR-SAR interferometry approach using the ERS data simulation. Depending on Envisat's data availability we will also present Envisat ScanSAR-SAR interferograms.
DE: 8110 Continental tectonics--general (0905)
DE: 8155 Plate motions--general
DE: 1243 Space geodetic surveys
DE: 1294 Instruments and techniques
SC: Geodesy [G]
MN: 2004 AGU Fall Meeting