Sentinel-1 TOPS DEM

[thomas123]

Hi,

I have created a DEM using the TOPS methodology in the tutorial. Everything went well, but my output DEM is kind of patchy. I have compared those patch with other DEM’s and they don’t refer to anything in particular. Also my DEM’S looks shifted by a 100m. Do you thing those patches could be the results of a phase diference caused by environmental condition such as freezing ground, snow or soil humidity?

Thanks,

thomas

[lveci]

You may need to fix errors using many image pairs to overcome errors in the unwrapping or atmospheric effects, etc. Remove outliers and try to get a consensus. Then terrain correct the final result.

[thomas123]

Thanks for your answer. How can I do that? I have to combine multtiple unwrapped interferogram? I need to use the function stack combine or something like that?

[ABraun]

How can I do that?

we discussed this approach here:

Interferogram averaging for DEM generation

I wondered if it's possible (and reasonable) to calculate multiple interferograms and average them for later phase to elevation calculation. I have Sentinel-1 A/B interferograms (6 days temporal baseline each) in an arid region with high coherence. I would like to exclude atmospheric effect by a combination of interferograms. But I struggle to do it in SNAP. When would be the best step to do the averaging? Directly on the filtered interferograms (I doubt that this makes sense) After unwrap…

[az_uct]

Hi Ivenci
Could you please explain how this is done? I have the same Issue as thomas123