Correction of distorted FPI interferograms to invert atmospheric winds and temperatures

Abstract

Fabry-Perot interferometer (FPI) is a vital optical device for measuring atmospheric wind and temperature, which is widely used worldwide for its simple structure and excellent accuracy. Nevertheless, the working environment of FPI could be light polluted by many factors, such as light from street lamp and moon, which results in distortion for realistic airglow interferogram and thus affects the accuracy for the wind and temperature inversion. We simulate the FPI interferogram and invert the correct wind and temperature from the full interferogram and three parts of it. Further analysis is performed using real airglow interferograms observed at Kelan (38.7°N, 111.6°E). Distortion interferograms cause temperature deviations, while the wind is not affected. A correction method is presented to correct the distortion interferogram by making it more homogeneous. The corrected interferogram is calculated again, and the result shows that the temperature deviation of the different parts is reduced significantly. Wind and temperature errors of each part are reduced compared to the previous ones. This correction method will help improve the accuracy of the FPI temperature inversion when the interferogram is distorted.