How to prepare ERS/ENVISAT images stack for PSI in SNAP5

Hi all,
I would like to process some ENVISAT image series to obtain the LOS deformation using PSI technique.
I’d like to use S1TBX on SNAP to process the data.
So how shoul I do?
I would appreciate if someone could help me, showing the workflow or any tutorial.
Thanks a lot!

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I think you could apply the same steps of Sentinel 1 EXCEPT OF the DEBURST, AND OF COURSE USE AN APPROPRIATE CORR. FOR ERS AND ENVISAT

1- you need to apply orbit and
(Apply orbit for ERS AND ENVISAT)

2 -Then you can add all products to the backgeocoding.

3- Create a stack of interferograms on the resulting stack.

4- Add an elevation band to the interferogram stack.

5- Add Stack and to the stamps export.

3- Create a stack of interferograms on the resulting stack.

You must remember that there are problems with Topographic Phase removal tool in SNAP.
http://forum.step.esa.int/t/topographic-phase-removal-of-s-1-stack-for-stamps-export-has-some-problem/6150

Hi @annamaria,
Yes, I have in mind that there are problems with the Topo Phase Removal tool in SNAP.
I have read your post:

The StaMPS export tool needs two layers: a layer with coregistred images+deburst (layer1) and another layer (layer2) with interferograms which topographic phase is removed.
_Layer1 is obtained with backgeocoding+deburst of images. _
_As the results obtained with the topographic tool are wrong, I created interferograms for individual pairs and then created a stack (layer3). _
_For example, in case of 5 images, of which 1 master and 4 slaves, i created layer3 in this way: _
_1) I processed 4 single pairs (backgeocoding, deburst (and possibly subset), interferogram, topographic phase removal, export) and I obtained 4 different results. _
2) I created a stack of these 4 results / pairs (with Create stack tool). In this stack, the images must be renamed with a name compatible with what appears in layer1 (for example, if the pair is 29Apr2015 and 22Jul2015, in layer1 you have i_IW1_VV_mst_29Apr2015, q_IW1_VV_mst_29Apr2015, i_IW1_VV_slv_22Jul2015, q_IW1_VV_slv_22Jul2015, in layer3 your renamed image must be i_ifg_VV_29Apr2015_22Jul2015 and q_ifg_VV_29Apr2015_22Jul2015).
After layer3 was created, I used layer1 and layer3 for export into stamps.

So, if I understand well, in order to avoid problems with the Topo Phase Removal, I have to create interferograms for individual pairs and apply the Topo Phase Removal to those individual pairs, isn’t it?

Many thanks!

Yes, and after you must create a stack with interferograms.

So to apply Topo Phase Removal only for one pair, and add the result to the stack to the other pairs (Which they are not TPR done for them)?

Is that what you meant? Many thanks in advance

For example, in case of 5 images, of which 1 master and 4 slaves, i created layer3 in this way:

  1. I processed 4 single pairs (backgeocoding, deburst (and possibly subset), interferogram, topographic phase removal, export) and I obtained 4 different results.

You must process single pairs individually and after you must create a new stack with these results.

The point is still vague to me (What do you mean [quote=“annamaria, post:7, topic:6346”]
You must process single pairs individually and after you must create a new stack with these results.
[/quote]) ?

Do you mean apply Phase Topo Removal for each single pairs separately? And then add them to the stacking?

OR…

Apply PTR. only for one individual Interferogram without the other and add it to the stack?

For example in case of 5 images, of which 1 master and 4 slaves:
step1: master+first slave -> coregistration, if necessary deburst (and possibly subset), interferogram, topographic phase removal, export.
step2: master+second slave -> coregistration, if necessary deburst (and possibly subset), interferogram, topographic phase removal, export .
step3: master+third slave -> coregistration, if necessary deburst (and possibly subset), interferogram, topographic phase removal, export .
step4: master+fourth slave -> coregistration, if necessary deburst (and possibly subset), interferogram, topographic phase removal, export .
step5: create a stack with results of step1,step2, step3, step4.
Is it more clear now?

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Thank you so much, yes of course

Hello, I ve done everything that you said above, but when i am trying to do te Export to StaMPS command , i got an error that says “The product ‘ifg_dinsar_Stack’ already contains a band with the name ‘i_20061013.rslc’”. I would like to mention that I work with Envisat data.
Could anyone know about it?

Thank you !!!

Did you also use AP (Alternate Polarization) mode data? It contains HH and VV of the same date which potentially leads to such errors.

Hi,

I’m also planning on processing ENVISAT in S1TBX on SNAP to ultimately export it to StaMPS in Matlab, and run the PSI algorithm there.

I was wondering (given that the conversation dated from 2017): are the problems with SNAP’s Topographic Phase Removal still around after the release of the current version of SNAP (7.0)?
And if the situation is different now, what is the recommended workflow for ENVISAT processing in SNAP for PSI preparation?

Thanks in advance

Stripmap data is less difficult, because you don’t need Split, Deburst…

For using ENVISAT in StaMPS I recommend

  1. Subset (if necessary)
  2. Apply orbit file
  3. coregistration (one master, multiple slaves)
  4. Interferogram generation (including topographic phase removal)
  5. StaMPS export with the outcomes of #3 and #4
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I want to process Envest images for PSI, but I do not know what software I should use. Can anyone guide me? Can they be processed with Snap?

@despina98 you can do the preparation in SNAP as suggested here and then use StaMPS for the PSI analysis

So where do I download Envest images?

here: https://esar-ds.eo.esa.int/oads/access/collection

Oh thank you very much.Which image mode should I download?

IMS because it has phase information