Research On Positioning Method Of General Aviation Aircraft Based On BDS

The safety and regulatory issues of general aviation aircraft are very important.Although the BDS can provide basic positioning services for general aviation aircraft,its positioning accuracy needs to be improved.The research focuses on how to improve the ambiguity resolution method of BDS three-frequency signal and the data fusion algorithm of BDS/INS integrated navigation.The design and test of high precision general aviation aircraft positioning system are realized。Firstly,the improved ambiguity resolution algorithm of BDS three-frequency signal is studied.The basic theory of classical three-frequency ambiguity resolution method is analyzed.The reason for the low success rate of ambiguity resolution under medium and long baselines is determined.Then an improved three-frequency ambiguity aesolution algorithm is designed.Two original single-frequency carrier phase observations are used to estimate the double-difference ionospheric delay,and the double-difference ionospheric delay correction of Narrow-Lane is smoothed by it.This method effectively weakens the influence of ionospheric delay on ambiguity resolution in Narrow-Lane,and the success rate of ambiguity resolution for Narrow-Lane is improved.Secondly,the improved data fusion algorithm of BDS/INS integrated navigation is studied.Aiming at the low tracking performance problem of Unscented Kalman Filter(UKF)algorithm,an improved UKF data fusion algorithm is designed.On the one hand,the state of the previous moment is used to adjust the scaling factor.By adjusting the distribution of sample points,the estimation performance of the algorithm is improved.On the other hand,the sequential processing method is used to reduce the computational complexity.Experiments show that the algorithm can effectively improve the positioning accuracy.Finally,the general aviation aircraft positioning system is designed.Based on VS and MySql database platform,the system integrates the improved algorithm of ambiguity resolution and the improved data fusion algorithm of BDS/INS integrated navigation.The design of system,communication mode,database and client is completed.The system not only realize the real-time monitoring of the position and status but also can play back the historical track for the general aviation aircraft.