Inversion of Earth's Neutral Atmospheric Parameters and Bending Angles with GPS Occultation Data

The theory and the procedure of inversion of Earth's neutral atmospheric parameters and bending angles with GPS Occultation data with Abel integral method are introduced.Based on the theory,two methods of ionospheric correction,linear phase correction and linear bending angle correction,are described.Two approaches to determine the upper bound of Abel inversion are discussed.The method for optimizing the measured bending angles on the upper bound are also analyzed.Pre-processing steps of Level2 data of UCAR,including transferring the coordinates of GPS and LEO satellites from the coordinate system of ECI to ECEF and low-pass filtering of the phase delay data,are discussed.Last,the computation with data of certain occultation event is done and the results are analyzed.Some conclusions have been drawn.