Hello,
I’m a new user of this forum and I am new to interferometry, actually, it is not in my study field, but I am in need to proceed in learning about the latest, since I need some information for my thesis. I want to know how to make a deformation map in time, especially focusing on civil structures by using the Sentinel 1 data, or Cosmo SKy Med. I already saw the tutorials on the Copernicus page, but the example is made using only two frames, and I think I definitely need to elaborate more than 25 to have my information. But I am not very good with SNAP , so what i’m asking is if you know any tutorial that I can follow.
Classic InSAR analyzes phase changes on the base of image pairs (e.g. A+B)
If you want to observe phase differences over a longer period, you can either compute more pairs (B+C, C+D, D+E…) or compute differences between multiple dates to one primary image (A+B, A+C, A+D,…).
An example on the combination of multiple images is given at the end of this tutorial: Sentinel-1 TOPS interferometry, but it only computes an average displacement over multiple image pairs.
Another example is given in this tutorial: https://eo-college.org/resource/insar_deformation/ (only the last part on multi-temporal analysis is valid, the rest is quite outdated from a technical perspective)
There are distinct methods on time-series analyses of displacements, but as you are new to InSAR I would not recommend rushing into these to quickly. Nevertheless, the collection on this topic is here: StaMPS - Detailled instructions
I saw the second link of eo in another topic, but,for some reason I can’t see the video tutorial.
So the only way to do it, is to repeat the process for every couple of images?
another question, so i can use the Cosmo SkyMed data with SNAP? ( i still haven’t downloaded any data yet, but I want to be sure before asking for images from them)
Hi @ABraun,
do you know if also StaMPS (with data from Snap) supports COSMO Skymed data? Because I’m doing some test (not a real project) to verify if the Snap+StaMPS workflow “works” with CSK images. But I have only 2 images of this type, so in StaMPS it’s not possible go beyond the step 2 with only 2 images.
Thanks
Technically, I see no problem to process CSK data with StaMPS, the preprocessing is even less complicated. But testing with two images will probably fail because the temporal measures (e.g. amplitude dispersion) cannot be calculated correctly based on only two input images.
Another question. what is the main difference between HH and VV polarization? I noticed that sentinel1 have both of this options, indeed the CosmoskyMed only have HH polarization
Horizontal and vertical waves are sensitive to different surfaces and objects.
For Interferometry, co-polarization (VV or HH) is similarly fine, but VV dominates for Sentinel-1 because of its monitoring applications.
Until now I thought that there was only the possibility of doing Multi-temporal Interferometric Synthetic Aperture Radar with Stamps and some payment program such as Sarproz, that reason is because recently I am introducing myself in the study of this technique. So this post is a big surprise.
What arises me a series of doubts, that please I would like to solve without going into too much detail. so I would like to know what advantages-disadvantage exist between doing it with the SNAP tool compared to Stamps, or in other words what is the difference between both tools to select one of them to use conveniently.
Thank you very much for the reply
SNAP itself toes not provide persistent scatterer functionalities, but it allows to pre-process the data as required by StaMPS (runs in MATLAB). So basically, to do an analysis as provided by Sarproz or ENVI Sarscape you need both SNAP and StaMPS. Besides that, SNAP currently does not feature data preparation for small baseline approaches (SBAS), although they are technically possible with StaMPS.
I understand or I suppose that using only SNAP, the process would be much slower (if we use 20 images for example) as it is not completely automated, in addition to worse results or with less accuracy than Stamps
True?
not necessarily slower, but more user action and configuration is required than with commercial products.
The quality of the results should be equally fine (comparing single master approaches)