Properly using Coherence images in the Time Series tool

[Jboissonnat]

Hello,

I have a problem with the Time Series tool ; I am trying to produce graph of coherence over time, with values extracted from polygone, so as to see how it changes for different objects over a year. I did it with backscatter images and it worked :

But when I try to do it with SLC coherence products, I obtain a graph that doesn’t seem to use all the images, or the acquisitions dates that I have. Here I use 3 different images but only two points appear on the graph :

I guess it is because coherence images are from two images with different day of acquisition ? Is there a way to use properly coherence images to produce graph where each of these is represented by one point ?

Also the text file that can be extracted from the graph gives this, if it can help :

I precise that I created a stack with my coherence images (from the .dim files), because nothing appeared on the graph just with all images opened separately on SNAP (although it worked for the GRD backscatter images).

I already looked into these topics, but I didn’t found an answer :

Generate Sentinel-1 coherence time-series

Hi all, I am trying to process the S1 SLC data into coherence time-series. However, I had no previous experience on that and I got stopped at the first step. My question is can I use any two images to generate coherence or I have to use images with a 12-day revisit with the same orbit and slice number? Thank you. Yuting

Coherent change detection

Hi every one, i need to Perform coherent change detection(CCD) with sentinel 1 (SLC) . What is the ideal steps to do that . regards

Stack of coregistered Amplitude and coherences

Hi, i’m pretty new in thi blog, but i’m using SNAP since a couple of years. My question is: is there any way to create a Stack of coregistered amplitude and cohrences (starting from a stack of Interferometric SLC IW S1 images)? The problem is that i need to extract coherences from adjacent in time images, that means that the master of all the stack is fixed while the master of every coherence is changing. Thanks in adance

Interferogram averaging for DEM generation

If they were coregistered to the same master initially then you could use merge or create stack. If they all have different masters then you may need to terrain correct and then create stack. Depending on how accurate the geolocation is you could also create stack with resampling but, be careful this doesn’t ruin the phase. The safest way would be to coregister all of the products first but currently you can’t do different combinations of interferograms. We’ll be adding this functionality next …