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InSAR Scientific Computing Environment version 2
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Statevector is mismatched to the reference SLC in coregistered IW xml files #887

Closed Leiguo924 closed 1 month ago

Leiguo924 commented 1 month ago

The IW*.xml of coregistered secondarys after fullburst merge has wrong statevector, which was adapted from the reference IWs. Is there any specific reason to do so? Or just a bug?

After looking into the code, I think it comes from the _resampwithCarrier.py, in which the template burst class is assigned with the burst from reference SLC, and only the data inside the burst is updated.

Anyway, it could be a bug for some other processing flow that needs the orbit parameters...

https://github.com/isce-framework/isce2/blob/b011e465a9c5c8f516c8ef70aa812377c2234720/contrib/stack/topsStack/resamp_withCarrier.py?plain=1#L184-L293

piyushrpt commented 1 month ago

It is by design. The pixels once coregistered - must use the geometry from the reference imagery for all geolocation operations. Coregistered SLCs can themselves be treated as independent products from this stage onward.

In theory, the phase of pixels have already been corrected for slant range differences at this stage - there is no need to carry around original orbit information.

Leiguo924 commented 1 month ago

It is by design. The pixels once coregistered - must use the geometry from the reference imagery for all geolocation operations. Coregistered SLCs can themselves be treated as independent products from this stage onward.

In theory, the phase of pixels have already been corrected for slant range differences at this stage - there is no need to carry around original orbit information.

Thanks a lot. Since I have encountered an issue with autoRIFT module, it needs the orbit information to run Geogird. I just found another way to solve it!