Correction of phase anomalies of atmospheric emission spectra by the double-differencing method

Atmospheric emission measurements with the cryogenic airborne Michelson Interferometer for Passive Atmospheric Sounding revealed strongly disturbed phase and magnitude spectra. They were corrected with the double-differencing method: The phase information implied in the line structure of atmospheric spectra is used to specify a phase shift with respect to an instrumental phase spectrum, which was determined once from calibration measurements with the differencing method of Revercomb et al. [Appl. Opt. 27, 3210 (1988)].