Version 1
: Received: 24 December 2021 / Approved: 27 December 2021 / Online: 27 December 2021 (10:42:31 CET)
How to cite:
Si, X.; Li, X.; Chen, H.; Bao, S.; Xu, H.; Zhang, L.; Huang, W. Research on a Partial Aperture Factor Measurement Method for the Agri Onboard Calibration Assembly. Preprints2021, 2021120421. https://doi.org/10.20944/preprints202112.0421.v1
Si, X.; Li, X.; Chen, H.; Bao, S.; Xu, H.; Zhang, L.; Huang, W. Research on a Partial Aperture Factor Measurement Method for the Agri Onboard Calibration Assembly. Preprints 2021, 2021120421. https://doi.org/10.20944/preprints202112.0421.v1
Si, X.; Li, X.; Chen, H.; Bao, S.; Xu, H.; Zhang, L.; Huang, W. Research on a Partial Aperture Factor Measurement Method for the Agri Onboard Calibration Assembly. Preprints2021, 2021120421. https://doi.org/10.20944/preprints202112.0421.v1
APA Style
Si, X., Li, X., Chen, H., Bao, S., Xu, H., Zhang, L., & Huang, W. (2021). Research on a Partial Aperture Factor Measurement Method for the Agri Onboard Calibration Assembly. Preprints. https://doi.org/10.20944/preprints202112.0421.v1
Chicago/Turabian Style
Si, X., Liming Zhang and Wenxin Huang. 2021 "Research on a Partial Aperture Factor Measurement Method for the Agri Onboard Calibration Assembly" Preprints. https://doi.org/10.20944/preprints202112.0421.v1
Abstract
A partial aperture onboard calibration method can solve the onboard calibration problems of some large aperture remote sensors, which is of great significance for the development trend of increasingly large apertures in optical remote sensors. In this paper, the solar diffuser reflectance degradation monitor (SDRDM) in the onboard calibration assembly (CA) of the FengYun-4 (FY-4) advanced geostationary radiance imager (AGRI) is used as the reference radiometer for measuring the partial aperture factor (PAF) for the AGRI onboard calibration. First, the linear response count variation relationship between the two is established under the same radiance source input. Then, according to the known bidirectional reflection distribution function (BRDF) of the solar diffuser (SD) in the CA, the relative reflectance ratio coefficient between the AGRI observation direction and the SDRDM observation direction is calculated. On this basis, the response count value of the AGRI and the SDRDM is used to realize the high-precision measurement of the PAF of the AGRI B1 ~ B3 bands by simulating the AGRI onboard calibration measurement under the illumination of a solar simulator in the laboratory. According to the determination process of the relevant parameters of the PAF, the measurement uncertainty of the PAF is analyzed; this uncertainty is better than 2.04% and provides an important reference for the evaluation of the onboard absolute radiometric calibration uncertainty after launch.
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
