About single polarization and dual polarization SLC interferometry

I use following S1 SLC data to create DEM:
I split both using VV polarization but when doing interfergram the results are wrong.
The ASF Baseline tool show the perpendicular baseline is 145m but after applying orbit file the stack overview show the baseline is 6680m.
I successfully do that using ENVI Sarscape,so what’s the problem?
Whether single polarization and dual polarization SLC data can’t do that in SNAP?
here’s the fig phase and coh


The repeat-period is not a multiple of 6 days, so your chosen pair is not suitable for InSAR. The ASF baseline estimate must be incorrect.

here’s the overview result and the time baseline is 6 days

I have tried some different pairs in the same area,the overview results are following:

I don’t know why sometime S1A and S1B baseline are incorrect

So it says, but the filenames are more fundamental and 12Feb to 19Feb is 7 days…

It’s not that the baseline is incorrect but in the first case the time separation between images is. Could be corrupted metadata, you can always try to re-download the scene. In any case 7 days does not make a viable InSAR-pair for S-1.

Two image start almost at 00:00,the S1A just pass 20170218 a few second,their time separation are almost 6 days not 7 days.From the filename we can also find their imaging time.
time1 time2

You are correct, the 2nd image is actually straddling the date boundary(!). So there is either a problem with the metadata (orbits?) of the one or both of the scenes, or there is a bug in SNAP.

Did you update the orbits to precise in your processing?

This is the first time I see this. This is very confusing indeed !

I have tried apply orbit file and the baseline reduce to 6680m,reduced but still incorrect,and the interferometry is after coregistration,so it may be a bug

I find maybe it’s not about imaging time.I have tried more pairs along the orbit and track,all of the S1A and S1B have incorrect baseline whether the imaging time cover in one day or two days.here are the result.

but in other track and orbit,the baseline is right.
here are two pairs:

how to explain this?plz help me.

All of the SLC S1A and S1B data of the following path are incorrect not about imaging time.
the S1B only have a few images in 2017 of each frame.So I choose 20170212 for S1B and the same frame of S1A(20170218 or 20170219) and the results are at the bottom of the topic, I’m confused about this.

@lveci could you check if this could be a bug, one of the images in the pair straddles the date-bounday and the baselines seem incorrect?


Could you please provide more details on your processing steps so that we can repeat the problem? Thanks

I have done nothing but use the stack overview to estimate the baseline.And I found in the orbit all the S1A and S1B have wrong baseline.After trying different pairs, I find that the S1A in that orbit may have someting wrong because in my estimating trial,S1A and S1A sometimes have incorrect baseline while S1B are correct all the time.Can you help me to solve that problem?

Below are the coherence and interferogram we obtained by running the following graph with your data:

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