JPSS-1 VIIRS version 2 at-launch relative spectral response characterization and performance

Evaluating the Magnitude of VIIRS Out-of-Band Response for Varying Earth Spectra

“…As such, complete pre-launch evaluation of sensor geometric performance, including RSR co-registration and spatial response characterization, is a necessary requirement established to meet the goals of the remote sensing community [8][9][10][11][12][13]. Moeller et al and Schwarting et al conducted extensive laboratory RSR characterization efforts for the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument series allowed for characterization of the full optical path and any optical or electronic cross talks for nearly all VIIRS bands [1,2,[14][15][16][17][18][19].…”

“…Pre-launch, the VIIRS RSRs are specified by their band center, bandpass, extended bandpass, and out-of-band (OOB) response, which are determined from the complete integrated signal. Figure 1 is a schematic recreated from several such figures of Moeller et al and Schwarting et al (e.g., " Figure 1" in all listed Moeller et al references) that illustrates the spectral performance specification metrics for VIIRS, in which the band center is the central wavelength between the 50% response-level bandpass bounds, and the extended bandpass is bound at 1% response levels with associated lower and upper wavelength (λ) thresholds, beyond which are the OOB regions [1,2,[16][17][18][19]. Moeller et al and Schwarting et al conducted these characterization efforts for both the Suomi National Polar-Orbiting Partnership (S-NPP) VIIRS Government Team (GT, consisting of NASA, Aerospace Corp., MIT/Lincoln Lab, and Univ.…”

“…The analysis was also performed for versions 1 and 2 (V1 and V2) of the first Joint Polar Satellite System (JPSS-1/NOAA-20) VIIRS RSRs, and V1 and V2 of the future JPSS-2 VIIRS RSRs. With laboratory measurements, they assessed spectral performance metrics with respect to their specified values, results of which are given in tables along with listed bandpass and extended bandpass limits [1,2,[16][17][18][19]. [1,2,[16][17][18][19].…”

“…This knowledge is important for scene-dependent inter-calibration efforts, for environmental retrievals, and in regard to error consideration for cloud/aerosol property computations. [1,2,[16][17][18][19]. The lower and upper wavelength 1% response limits that separate the extended bandpass and out-of-band (OOB) regions are designated as λ lower OOB and λ upper OOB, respectively.…”

“…The reason both S-NPP VIIRS RSR products are studied is because despite the post-launch endorsement of the NG RSR release by the Government Team, the GT RSR release, which diverges from the NG RSR "primarily due to analysis differences that only affect the RSR at low response levels," may still be of "investigative interest" to the remote sensing community as an "alternative high quality RSR" [1,2,20]. For the NOAA-20 and JPSS-2 VIIRS, there is no distinction between GT and industry RSR releases because only the former carried out a pre-launch characterization effort [17,19,21]. Users within the inter-calibration community and product teams that rely on VIIRS should find these results useful, even if only for assurance that OOB contribution is within acceptable tolerance for their specific application, which should often be the case especially for the newer VIIRS.…”