Simulation of a simultaneous traceable spectroradiometric calibration of an imaging spectrometer

Spectroradiometric calibration aims to determine the instrumental spectral response function (ISRF) parameters and radiometric coefficients of an instrument’s spectral bands across all spatial pixels. Typically, this is done by making separate spectral and radiometric calibration measurements. We present a method for the simultaneous traceable spectroradiometric calibration of an imaging spectrometer, using the Spectroscopically Tunable Absolute Radiometric, calibration and characterisation, Optical Ground Support Equipment (STAR-cc-OGSE) facility. We performed the forward simulation of calibration data acquisition by convolving input spectra with the sensor model’s response and simulated a slit scattering function (SSF)-based calibration, allowing for both ISRF coefficients and the absolute spectral responsivities to be accurately retrieved from a single series of measurements. We show how the SSF method minimizes uncertainties compared to the traditional spectroradiometric calibration approach.