Correction of detector nonlinearity induced striping in VIIRS day/night band nighttime imagery

摘要

Striping has been observed in nighttime imagery of VIIRS DNB onboard both Suomi-NPP and NOAA-20 satellites. Image analysis indicated that stripes usually come from the detectors with residual nonlinearity at very low radiance levels, whose High Gain Stage gain coefficients are biased due to the errors in the corresponding DNB gain ratios. Such bias is more than 10% for certain aggregation mode and detectors. By processing the VIIRS recommended operating procedure data with the linear regression method, we corrected the nonlinearity induced bias in the DNB gain ratios. Comparison of the original and the reprocessed DNB nighttime images shows that striping is significantly reduced, in particular under moonlight illumination.