Base line in SNAP

I am getting perpendicular baselines in negative (-20.35) with sentinel-1 data. I have a problem while removing topographic phase for displacement mapping. The interferogram is showing similar results before removing the topographic phase and after removing the topographic phase. Is baseline is the problem here? What shall I do? I need to find out the deformation map. Can anybody please explain? I have also used different DEMS here which are provided in this software.

I would consider 20 m as the very limit for interferometry. If both satellites have nearly the same position you cannot get a pronounced topographic phase.

Thank you so much. I have now considered both short and long baseline to see the difference.

Hello,i am facing the same problem these days.can you share with me about how do you find the
sentinel-1A pairs with a baseline more than 200m?
my email: li798210534@gmail.com

Hi,lidahai, sorry to your problem, I have no idea to find interfermetry pairs with baseline larger than 200m. Best wishs:sweat_smile:

you can use the ASF baseline tool to identify image pairs with larger baselines:


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Thanks anyway.The method provided by @ABraun turned out to be instrumental . Maybe you can try it next time.:smile:

amazing! thanks! @lidahai @ABraun:grinning:

Hi @ABraun

I have a -ve perpendicular baseline. It is my understanding that the optimal Bperp is between 150m & 300m. Does this also apply to its negative counterparts: -150m & -300m? Thanks

Yes, the sign only indicates on which “side” the slave acquisition is from the master acquisition. If you reverse the master and slave the sign changes.

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thank you @mengdahl, much appreciated :smiley:

Hello falahfakhri. What is the shortcut to the baseline?Thanks.

Hi ABraun,

Some months ago I could create a baseline chart using the ASF baseline tool as in video you uploaded, but Now, this tool seems to be different. I cannot switch to SBAS beta from PS baseline chart as below

I have no idea, sorry.

Hello,

I found a problem while trying to plot the baseline chart using the ASF baseline tool. I can’t get the plot for any Sentinel1 granule. Does anyone have the same problem? Could you please suggest solution to get the baseline chart?
Thank you.

It was reported here yesterday: Baseline Tool

No solution however yet, hopefully this bug will ne fixed soon. Has anyone reported it to ASF yet?

@ABraun yes i reported through ASF feedback portal

The ASF baseline tool is now working

Hi all,
I am not sure if I am doing it right by reactivating this thread but I have found something that is a bit confusing to me. Please forgive me it this is my ignorance as I am somewhat new to interferometry.

I also need to find out the Bperp for the S1A data pair that I have downloaded. I tried it in SNAP and it is giving me |8.29| m while the same data pair is giving me |1| m in ASF Baseline tool. Please have a look at the figs attached.
It will be highly appreciated if someone may please help me in understanding why this difference has arisen here.
Thank you in advance.

maybe the ASF data uses different orbit information. Have you applied orbit files in SNAP already?