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TerraSAR-X/TanDEM-X bistatic DEM generation
Added by 秦 小 about 7 years ago
Hi
I am using the bistatic TerraSAR-X/TanDEM-X data to generate DEM with high resolution and accuracy. But the demo shows the process using SRTM as external DEM to unwrap the diff-phase. Why can't it be processed as the regular steps, like baseline estimation, unflatted, filterd, unwrap the phase, change the unwrapped phase to height? I try to process with the regular step, but the unflatted image is different from the QL_SLT_phase image given by DLR. And the baseline differs from the baseline in the XML file slightly
My question is why should the data be processed using the external DEM to unwrap the differential phase instead of the regular processing steps?
Best regards!
Replies (1)
TerraSAR-X/TanDEM-X bistatic DEM generation - Added by Charles Werner about 7 years ago
Hello,
The reason is that using an existing DEM first to simulate the
interferometric phase and subtraction of that phase removes many fringes
making the phase unwrapping more likely to be correct. Then the
unwrapped phase can be scaled to obtain a correction to the existing
DEM. This process can be iterated a few times until you converge to the
final high-resolution DEM.
Best regards,
Charles