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The Day Night Band (DNB) has been featured on the first two VIIRS instruments aboard the Suomi NPP and NOAA-20 satellites that are both currently in service, and to date prelaunch sensor level testing has been completed for the next two instruments in the series JPSS-2 and JPSS-3 VIIRS. Radiometric testing had found nonlinear behavior in the DNB especially at low radiances. The non-linearity was especially problematic the DNB of NOAA-20 VIIRS which resulted is revisions to the ground test program and operating the instrument in a modified “option 21” configuration on-orbit to mitigate the impacts of the non-linearity. Still, non-linearity remains both in NOAA-20 under option 21 and subsequent VIIRS builds, and this nonlinearity is gain, mode, detectors, and sample dependent. In this analysis we look at results from the most recent three VIIRS builds (NOAA-20, JPSS-2, and JPSS-3) where more extensive prelaunch DNB calibration is available to determine the extent on the non-linearity that remains and its effect on the on-orbit calibration. Especially important is the cross-calibration that transfers the low gain stage calibration coefficients calculated from the solar diffuser to the other gain stages. This process leverages low signal samples where non-linear effects are most significant. Tables have been generated to select the optimal linear samples and improve this process.
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