Sentinel-1 product commissioning starts right after the launch and encompasses the verification, calibration and geophysical validation of the products:
- IPF and product verification encompasses:
- Verification of the L0, L1 and L2 product format and main annotations
- Product family consistency, e.g. verification of the consistency of measurement for GRD HR, FR and MR.
- Verification of the main processing algorithms:
- Processing algorithm (Doppler estimation, focusing, ground range projection, debursting, swath stitching)
- Radiometric correction ( elevation antenna patterns, TOPS scalloping, range spreading loss, etc.)
- IPF normalization:
- Verification of the image dynamic and IPF gain setting
- Sub-swath radiometric merging
- Product performance assessment:
- Point target impulse response function analysis (spatial resolution and sidelobes )
- Ambiguity analysis (range and azimuth)
- Radiometric resolution and equivalent number of loss measurement
- Noise equivalent radar cross-section assessment
- Geometric assessment
- Burst synchronisation assessment
- L1 product calibration encompasses:
- absolute and relative radiometric calibration
- polarimetric calibration
- geometric calibration
- L2 geophysical validation encompasses:
- Verification of the geophysical variables against independent external measures like modal data, buoys or other EO data source