Comparison of two methodologies for calibrating satellite instruments in the visible and near-infrared

Published

December 10, 2015

Author(s)

Steven W. Brown, Keith R. Lykke, Robert A. Barnes, Bruce Guenther, James J. Butler, Thomas Schwarting, David Moyer, Frank DeLuccia, Christopher Moeller

Abstract

Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field-of-view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered.

Citation

Applied Optics

Volume

54

Pub Type

Journals

Download Paper

https://doi.org/10.1364/AO.54.010376

Keywords

laser, calibration, radiance, satellite sensor, Suomi NPP, VIIRS

Citation

Brown, S. , Lykke, K. , Barnes, R. , Guenther, B. , Butler, J. , Schwarting, T. , Moyer, D. , DeLuccia, F. and Moeller, C. (2015), Comparison of two methodologies for calibrating satellite instruments in the visible and near-infrared, Applied Optics, [online], https://doi.org/10.1364/AO.54.010376 (Accessed March 13, 2025)