sarproz-group

Unwrappin APS phase values

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    • #5448
      n-ghasemian
      Participant

        Dear Dr. Perissin,

        I am using the multi-temporal analysis module of SARProz (compiled version). I need raw phase values (before atmospheric correction) for my research. I assume that atmospheric correction is an unavoidable step in the multi-temporal analysis, and I can not skip it. The strategy that has come to my mind to get raw phase values is as follows:

        1. to export APS phase values
        2. to extract displacement phase values after atmospheric correction using the export module
        3. the algebraic sum of the above parameters would give raw phases.
        The problem is that I think the exported APS phases are wrapped cause they are all within [-pi, pi] range. So, I can not sum them with displacement phases, which I assume to be unwrapped.

        Is there a way to get unwrapped APS phase values? Alternatively, the raw unwrapped phases?

      • #5450
        periz
        Keymaster

          hi,
          1. if you want to work on data in the way you describe, you should use matlab.
          2. to read data in sarproz (in matlab), you can use the “leggi” function https://www.sarproz.com/groups/sarproz-group/forum/topic/aps-processing-4/
          3. using “leggi” you can directly read the original images and perform all what you need without caring about APS signals
          4. alternatively, you can use the sparse geocoding function to export phase values of your images one by one on sparse points in csv format. longer way than the first above, but still workable.

          • #5464
            n-ghasemian
            Participant

              Thank you for your reply Dr. Perissin. Could you please explain more about the steps to get the raw interferometric phase values (just topographically corrected) using the PSI method in Matlab (my data is the time series of sentinel-1 images). I had already done the PSI method in the compiled version of SARProz, but I am confused about how to extract interferometric phases in the Pcode version?

          • #5452
            n-ghasemian
            Participant

              Thank you for your reply.

              I need to do topographic correction before extracting phase values. The phases should mostly contain atmospheric and displacement phases. How should I do topographic correction in Matlab?

            • #5454
              antig
              Participant

                You may set in module “Insar params” appropriate settings
                Do not filter and multilook interferograms check “Flattening” and “DEM remove”
                save settings
                genereate interfereograms in module “interferograms protsessing”

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