ABraun
April 10, 2017, 5:35pm
2
In general, there are many ways and different opinions on how to pre-process SAR images which makes it hard for beginners to get into it. For example there is much discussion on when is the best time for speckle filtering within the pre-processing.
For Sentinel-1 data there are some things which are widely agreed, please have a look at the following topics:
On the different products:
it means that its already ground-range corrected. Unlike SLC data the pixels’ areas are already of same size.
Astrium has made nice graphics for this case. They refer to TerraSAR-X but the principle is the same for most SAR satellites:
Slant Range Complex (SLC/SSC/L.1.1)
[image]
Data is neither multi-looked nor projected
Ground Range Detected (GRD/MGD/L1.5)
[image]
Data is multi-looked but not projected
Geocoded Ellipsoid Corrected (GEC/L2.0)
[image]
Data is projected but topographic d…
On suitable orders:
for SLC data I would suggest
TOPS Split
Apply Orbit file
Thermal Noise Removal
Calibration to Beta0*
TOPSAR Deburst
Radiometric terrain flattening
(Speckle filtering)
Range Doppler Terrain Correction
If you don’t need the phase information you can also download it as a GRD product and only apply the following:
Apply Orbit file
Thermal noise removal
Calibration to Beta0
Radiometric terrain flattening
(Speckle filtering)
Range Doppler Terrain Correction
or (if you don’t have much topography)…
On multi-looking:
Hello,
I am fairly new to the SAR processing and I am trying to learn the basics through the ESA Sentinel Toolbox tutorials, which are a valuable resource.
In the very first tutorial “SAR Basic Tutorial”, I don’t understand the role of the Multilooking process specially when compared with Geocoding.
According to the tutorial, the “Multilooking can be an optional step, since it is not necessary when terrain correcting an image”. But in the Terrain correction step of the tutorial, the input ima…
2 Likes