Batch SARSim Terrain Correction problem


I am using SAR-Simulation Terrain Correction to orthorectify Sentinel-1 Level-1 GRD data. I am using GETASSE30 DEM.
This works in Snap GUI. Now I want to build a graph to batch the operation.
I use the operator called SARSim Terrain-Correction.
The problem is that in the GraphBuilder only a subset of the settings are available. I cannot specify DEM and the GraphBuilder complains that the “Metadata attribute ‘DEM Resampling method’ not found”.

Can i be that the menu-item Sar Simulation Terrain Correction not the same as the operator called SARSim Terrain-Correction?

Is there another way to batch orthorectify Sentinel-1 Level-1 data?


If you look at the SAR Sim TC dialog from the Radar menu, it’s actually a graph. In the graph builder you will need to repeat the same operators as in this graph.

SAR Simulation -> Cross Correlation -> SARSim Terrain Correction

The GETASSE30 DEM is of low resolution and contains artifacts - it might work in orthorectifying rather smooth areas but over mountains using it will not lead to good results.

Thanks for your quick reply.
It works if I use all three steps in the graph.
However it is rather slow. Typically it takes appr. 8 minutes even on a rather well equipped machine. Is this expected?

Can you also confirm that this is the recommended way to orthorectify Sentinel-1 Level-1 data?

In principle SAR Simulation TC is only needed for missions where the quality of the orbits is not sufficient. For S-1 with restituted/precise orbits SAR simulation should not be necessary - the standard method would be to apply Range-Doppler TC.

BTW I assume you are outside SRTM-coverage since you mention GETASSE30 instead?

Hi Chris
Where you able to create a batch script for SAR-Simulation Terrain Correction.
If so, would you be able to share it? I am getting the same error that you got:
“Metadata attribute ‘DEM Resampling method’ not found”.
Let me know