Abstract

The Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the NOAA-20 satellite regularly performs on-orbit radiometric calibration of its reflective solar bands (RSBs) through observations of an onboard sunlit solar diffuser (SD). The incident sunlight passes through an attenuation screen (the SD screen) and then scatters off the SD to provide a radiance source for the calibration. The on-orbit change of the SD’s bidirectional reflectance distribution function (BRDF), referred to as the ${H}$-factor, is determined by an onboard solar diffuser stability monitor (SDSM) whose eight detectors alternately observe the Sun through another attenuation screen (the SDSM screen) and the sunlit SD. The products of the SD screen transmittance and the BRDF at the mission start for both the SDSM and RSBs and the SDSM screen effective transmittance were measured prelaunch. Large unrealistic undulations in the retrieved ${H}$-factor were seen when using the prelaunch screen functions. To improve the accuracy of the retrieved ${H}$-factor, shortly after the satellite launch, 15 yaw maneuvers were performed to further characterize the screens. Although significantly improved, the ${H}$-factor derived using the screen functions determined from the yaw maneuver data still has large unrealistic undulations, revealing that the solar azimuth angular step size of the yaw maneuvers is too large. In this paper, we add high-quality regular on-orbit SD calibration data to the yaw maneuver data to further improve the relative product of the SD screen effective transmittance and the BRDF at the mission start for the SDSM and the SDSM screen relative effective transmittance. The ${H}$-factor time series derived from the newly determined screen transmittance functions is much smoother than that derived from using only the yaw maneuver data and thus considerably improves the radiometric calibration accuracy.

© 2020 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
On-orbit characterization of the VIIRS solar diffuser and attenuation screens for NOAA-20 using yaw measurements

Junqiang Sun, Mike Chu, and Menghua Wang
Appl. Opt. 57(22) 6605-6619 (2018)

On-orbit characterization of the VIIRS solar diffuser and solar diffuser screen

Junqiang Sun and Menghua Wang
Appl. Opt. 54(2) 236-252 (2015)

Suomi NPP VIIRS solar diffuser screen transmittance model and its applications

Ning Lei, Xiaoxiong Xiong, and Jeff Mcintire
Appl. Opt. 56(31) 8676-8686 (2017)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (10)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (16)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription