Abstract
Degradation of system throughput for the near-infrared (NIR) bands of the Visible Infrared Imager Radiometer Suite (VIIRS) on the Suomi National Polar-orbiting Partnership (Suomi NPP) spacecraft was observed beginning shortly after the NIR bands were activated. The most broadly reported effects have been described elsewhere in terms of changes in sensor system gain and signal-to-noise ratio (SNR), without mention of spatial and spectral response, or radiometric and polarization characteristics. A full report on sensor system gain and SNR characteristics will be reported by others elsewhere; the spatial, spectral, polarization and radiometric characteristics are discussed here, along with data-quality implications of the telescope mirror degradation for VIIRS in the bands between 400 and 900 nm. While there are no changes to spatial characteristics, the gain, SNR, and spectral changes all are mitigated with well-defined, more-frequent lookup-table (LUT) corrections. Implications for SWIR band performance are covered also.
VIIRS On-orbit Spectral Throughput Degradation: A Physical Model with Specific Guidance on Handling Sensor Characteristics for EDR Development
Degradation of system throughput for the near-infrared (NIR) bands of the Visible Infrared Imager Radiometer Suite (VIIRS) on the Suomi National Polar-orbiting Partnership (Suomi NPP) spacecraft was observed beginning shortly after the NIR bands were activated. The most broadly reported effects have been described elsewhere in terms of changes in sensor system gain and signal-to-noise ratio (SNR), without mention of spatial and spectral response, or radiometric and polarization characteristics. A full report on sensor system gain and SNR characteristics will be reported by others elsewhere; the spatial, spectral, polarization and radiometric characteristics are discussed here, along with data-quality implications of the telescope mirror degradation for VIIRS in the bands between 400 and 900 nm. While there are no changes to spatial characteristics, the gain, SNR, and spectral changes all are mitigated with well-defined, more-frequent lookup-table (LUT) corrections. Implications for SWIR band performance are covered also.