High-dynamic High-precision Satellite Navigation Post Processing Technology Research Based On Pseudo-Range

GPS navigation system has been widely used in various fields in recent years.With the booming development of Chinese aviation and aerospace industry,especially,the special strategic significance increasingly shown by near space,hence,the research in high-dynamic and high-precision GPS navigation positioning technology is of great importance and value to application to near space.To determine the precision of aircraft’s navigation system and analyze its flight performance,it is required to use satellite observed data to complete high-precision measurement on the flight path after the event.The error source and consequent influences in single-frequency pseudorange positioning are researched to provide high-precision reference for high-dynamic aircraft.With the help of the combination of the GPS receiver in the aircraft and baseline station,and the means of post-processing,error influences in navigation positioning are eliminated.Error influences caused by satellite ephemeris and clock error in the course of GPS navigation positioning calculation are analyzed,and meanwhile Lagrange Interpolation Method,Chebyshev Fitting Method and Thiele-type Continued Fraction Interpolation Method which can recently weaken the aforementioned error influences are discussed.On that basis,a sliding interpolation method is raised and validated by comparison through practical examples.The method of eliminating the ionospheric delay error is emphasized to deal with influences brought by that error on precision of single-frequency pseudorange positioning.The scheme that the baseline station located at intersection of the ground line and extended line of a satellite’s connection line with an aircraft is selected to use the double-frequency carrier phase correction method to eliminate the above-mentioned error is suggested.Besides,to ensure a suitable baseline station for an aircraft to eliminate errors in navigation positioning,the relevance between the baseline station layout and other factors as ionospheric delay,satellite elevation angle and GDOP is studied,and a proper baseline station layout is figured out.The parameter estimation method applied to the single-frequency pseudorange positioning is explored.Star difference method is used to eliminate the receiver clock error in pseudorange observation equations.The calculation formula to obtain weights is deduced according to the satellite elevation angle,and the relevance between the satellite elevation angle and ionospheric delay residual.A dynamic simulation experiment is conducted to verify that the solution hereof provides high-precision navigation positioning reference for high-dynamic aircraft.