Radiometric calibration of the IKFS-2 on-board IR Fourier spectrometer for temperature and humidity probing of the Earth's atmosphere

摘要

Calibrating the data of a Fourier spectrometer consists of converting the interferograms measured by the device into the spectra of the input radiation with the required radiometric and spectral accuracy. The main problems of terrestrial radiometric calibration of an on-board Fourier spectrometer are to correct the nonlinearity of the photodetector system, to determine the spectral radiance of the radiation of an on-board blackbody, and also to determine the threshold spectral brightness of the device. This article presents the results of the radiometric calibration of a flying sample of the IKFS-2 apparatus, obtained in thermovacuum tests of the device at the Keldysh Center.