I checked the automatically downloaded SRTM DEM, and find one of them has serious problem. Please check the ‘DEM abnormal 2.jpg’ attached.

However, this problematic DEM covers the area outside of my study area, the four corners of which are marked in ‘DEM abnormal.jpg’.

So my questions, does it matter if leave this problematic…[Read more]

When i do PS time series analysis, i got the result as shown in the first figure ‘PS overview’. This figure shows all the PS points with their color rendered by the deformation rate. There is a very obvious spatial ramp pattern that northeast corner shows stronger subsiding while the southwest corner shows much less subsidence trend. It looks…[Read more]

Thanks for the suggestions.

Paul

When i am processing Sentinel-1 SLC time series datasets, i encountered with a problem. First, i cropped the study area with 20km radius, and processed the time series with APS (by followed the manual ‘Demo on APS….’). Then i geocoded the result and export into Google earth, and the result is shown as attached. The result shows the…[Read more]

Thank you very much for the suggestions. The coregistration works well now.
I did process the external DEM in SAR coordinates, but i did not choose ‘orthorectified’ in data export process, which is important. Besides, the data i am using is Sentinel data.

Have a great day,
Paul

I am currently dealing with SLC time series, and I need to coregister all images to the master image. I follow the step in the manual. After co-registration I opened SITE-PROCESSING- GCP selection – Keep current orbits (auto GCP). Then I applied Coregistration Refinedment (Optional). After all of these, I applied Extended Data Export…[Read more]

It is sentinel-1A data. One interesting thing is that in Site Processing – APS estimation, i generated the graph, and it gives me 25 auto point, and i chose a ‘best’ point with good distribution. Then, i moved to Site Processing -Sparse point processing. When i checked the distribution of the parameters, there is a…[Read more]

About the reference point choosing, i still have a question. When i read the SARPROZ tutorial ‘Demo: APS Estimation Multitemporal analysis with Sarproz’, it says that best reference point should reflects that both velocity and residual height distribution peak at 0. However, in the Site Processing – APS…[Read more]

The image below is the study (urban) area (central Florida) which features with buildings. My question is about choosing reference point. I studied the online material which says integrated residual height and velocity are supposed to be peak at 0 value. However, there might be that majority of PS are on…[Read more]