[Simulated annealing based phase correction of interferogram in Fourier transform imaging spectrometer].

Phase correction is one of the key technologies in the spectrum recovery of the Fourier transform imaging spectrometer. The present paper proposes a correction method based on simulated annealing algorithm to calculate phase error, which overcomes the disadvantage of the existing methods that can not correct the interferogram with noise. The method determines the phase optimum solution by controlling the phase decrease function, attaining objective function value by correcting interferogram data with random phase value generated in the phase range, and determining the objective function increment in accordance with the Metropolis criterion. The simulation result of the algorithm indicates that the optimized phase error is less than 0.5%, and both the error accuracy and stability of the spectrum-recovered relative spectrum is less than 1%, which is a great improvement compared with the existing algorithm.

[Spectral discrimination method information divergence combined with gradient angle].

The present paper proposes a spectral discrimination method combining spectral information divergence with spectral gradient angle (SID x tan(SGA(pi/2)) which overcomes the shortages of the existing methods which can not take the whole spectral shape and local characteristics into account simultaneously. Using the simulation spectra as input data, according to the interferogram acquirement principle and spectrum recovery algorithm of the temporally and spatially modulated Fourier transform imaging spectrometer (TSMFTIS), we simulated the distortion spectra recovery process of the TMSFTIS in different maximum mix ratio and distinguished the difference between the recovered spectra and the true spectrum by different spectral discrimination methods. The experiment results show that the SID x tan(SGA(pi/2)) can not only identify the similarity of the whole spectral shapes, but also distinguish local differences of the spectral characteristics. A comparative study was conducted among the different discrimination methods. The results have validated that the SID x tan(SGA(pi/2)) has a significant improvement in the discriminatory ability.