Parameter estimation in imaging Fabry-Perot Doppler spectroscopy

Fabry-Perot;Spectroscopy;Airglow;Aeronomy

Minin, Serge

关键词: Fabry-Perot;    Spectroscopy;    Airglow;    Aeronomy;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/29448/Minin_Serge.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Fabry-Perot spectroscopy has been used for many decades to observe optical phenomena in the Earth's upper atmosphere. The techniques have been evolving in recent years, with the major technical advancement being use of a CCD in the focal plane of the instrument. This dissertation rigorously addresses the issues of optimal instrument design and signal processing techniques in an effort to advance the precision and accuracy of estimated thermospheric wind velocities and temperatures. This dissertation starts with derivations of analytical formulas for uncertainties in parameters estimated by fitting a profile of a Gaussian emission line with an unknown background component. The issue of optimal selection of an instrument function is treated analytically for a Gaussian spectral shape and then extended for treating the realistic Fabry-Perot instrument function. The uncertainty in estimated parameters due to a large background emission is investigated in some detail.The second part of the dissertation investigates the contribution of spectral variation of background emission to uncertainty in estimated parameters and develops experimental and signal processing techniques to mitigate this uncertainty, with the hope of improving daytime airglow measurements. A set of measurements at different angles is optimized for investigating spatially variable wind fields by line-of-sight Doppler spectroscopy. Finally, two-dimensional fringe processing techniques are introduced with the goal of optimizing the use of collected data.