I created a DEM using S1A data.
The steps are below:
1 Open the Products
2 Coregister the images
Radar-Coregistration-S1 TOPS Coregistration
The tab of Read is the Master Image and the tab of Read(2) is the Slave Image.
all my Polarisations are VV
I am very confused as the orginal data is presented as 9: a lage rectangle
well after Coregistraton, the data is presented as 8: a rectangle much smaller
3 Form the Interferogram
4 TOPS Deburst
5 Phase Filtering
6 Export to SNAPHU
7 Unwrap Interferogram with SNAPHU
8 Open the files in S1TBX
9 Create the DEM -Convert Phase to Elevation
10 Geocode the DEM
well after all these steps, my result is:
TOPS Coregistration only supports the processing of single swaths. You selected IW3 in your screenshot (under ‘Subswath’).
You have to repeat coregistration for all three subswaths and then use the TOPS Merge operator.
all these, when it use as master image is ok, but the slave image is always black.
The extreme values don’t matter. They result from unwrapping errors and atmospheric disturbances of the phase signal. Have a look at your coherence layer. It tells you where the quality of the DEM is trustful.
If there is vegetation in your area, it is unlikely that you will receive a perfect DEM from repeat-pass InSAR because of temporal decorrelation.