Fig. 1. Fitting instrument phase with different interferometer temperature

Fig. 2. Phase regression residuals with phase correction procedure

Fig. 3. Phase error of fourier transform spectrometer
(a): Measurement phase; (b): Residuals phase after linear phase removed

Fig. 4. Complex radiometric calibration result
(a): Calibration spectral radiometric; (b): Phase residuals

Fig. 5. Radiometric uncertainty expressed as brightness temperature differences

Fig. 6. Calibration data with different method
(a): Calibration spectral radiometric; (b): Radiometric uncertainty