A new model for the phase correction of interferograms

Abstract

A new model for the phase correction is proposed for Fourier transform spectrometer interferograms. The new model consists of three sections including a digital all-pass filter, delayer and phaser. Therefore, the new model is named the ADP model. When the ADP model is applied to phase correction, the particle swarm optimization (PSO) algorithm is applied to resolve the ADP model. Simulation experiments for the phase correction of double-sided interferograms using the ADP model based on the PSO algorithm are given. Simulation results show that it is easy to implement higher phase correction precision by using the ADP model based on the PSO algorithm with lower iteration number. In the application experiment, firstly, Fourier-transform near infrared (FT-NIR) interferograms are corrected by the Mertz method, all-pass filter method and ADP model, respectively. Secondly, the spectra calculated from the corrected interferograms are applied to predict the concentration of an ethanol solution by the PLS algorithm. The results show that the predicted error of the spectrum corrected by the ADP model is less than those of the spectra corrected by the all-pass filter method and Mertz method.