Hi all,
I have a problem in creating a working xml graph in SNAP for an entire Sentinel1 tile, which performs multilook (ML) before coherence (Coh).
Besides the discussion which way is the right one from a technical/scientific point of view: ML → Coh OR Coh → ML, (SNAP prefers the coherence step before ML, while others, like SARscape, do ML before coherence), it should be possible to do both in SNAP.
Indeed, I have a working graph for a subswath:
Read – split – apply orbit file – back geocoding – topsar deburst – ML – coh – TerrCorr - write
But it does not work for an entire S1 tile or even a set of several tiles. It seems like TOPSAR-merge causes the problem here, when trying to merge more than one subswath.
The following was tested and does not work:
(1) All in one xml:
read – TOPSAR split – apply orbit file - backgeocode – deburst – ML – coh – merge - TerrCor – write
(2) processing in 2 steps:
step1 preprocessing and separation of subswaths:
read – TOPSAR split - apply orbit – write (BEAM-DIMAP)
step2 coherence processing:
read (step1 products) – backgeocode – deburst – coh – coh – merge - TerrCor – write
Returned error:
[Nodeld: TOPSAR-Merge] Source products are not from the same Sentinel-1 product
which is not true, because they are!
Has anyone faced the same issue or comparable?
Thanks!
