How to get georeferenced backscatter bands ?

I am using following matlab code to apply terrian correction on sentinel1 sar data to get georeferenced backscatter Gamma0 and Sigm0 backscatter bands. I am getteing AmplitudeVH and AmplitudeVV data georeferenced but not Gamma0 and Sigma0 bands. please suggest me how to get them also georeferenced.

% Terrain correction

disp('Performing terrain correction...');

[zone, ~, hemi] = getZone(infile);

if strcmp(hemi, 'S')

projection = ['EPSG:327', sprintf('%02d', zone)];

else

projection = ['EPSG:326', sprintf('%02d', zone)];

end

if ~isempty(extDEM)

demOption = sprintf(' -PdemName="External DEM" -PexternalDEMFile="%s" -PexternalDEMNoDataValue=0 ', extDEM);

else

demOption = ' -PdemName="SRTM 1Sec HGT" ';

end

system(['gpt Terrain-Correction -Ssource=', outputPath, demOption, ' -PmapProjection=', projection, ' -t ', outputPath]);

kuldeep

Answer 1

[Anshuman]

Hello kuldep,

To ensure that the Gamma0 and Sigma0 backscatter bands are georeferenced during terrain correction in your MATLAB code, you can check a few things:

• If you are using SNAP (Sentinel Application Platform) for processing, ensure that the processing graph is correctly configured to output Gamma0 and Sigma0 bands. You might need to modify the graph XML file to include these bands.
• Ensure that a calibration step is performed before terrain correction. This step is necessary to convert the raw amplitude data to Gamma0 and Sigma0. The calibration step should be part of your processing chain and might look something like this:

system(['gpt Calibration -Ssource=', inputFile, ' -PoutputBetaBand=false -PoutputGammaBand=true -t ', calibratedOutputPath]);

• Ensure that the 'gpt Terrain-Correction' command includes parameters that specify the output of Gamma0 and Sigma0. If you need to specify these in the command, you might need to adjust the processing parameters or configuration.

Hope these suggestions help!