GPS/BDS-3/Galileo精密单点定位模糊度固定

Ambiguity resolution for GPS/BDS-3/Galileo precision point positioning

为了进一步提高全球卫星导航系统(GNSS)多系统组合精密单点定位(PPP)精度和收敛速度,提出一种GPS/BDS-3/Galileo精密单点定位模糊度固定(AR)方法:利用武汉大学发布的多系统相位小数偏差产品(FCB),采用无电离层组合PPP模型,实现全球定位系统(GPS)/北斗三号卫星导航系统(BDS-3)/伽利略卫星导航系统(Galileo)三系统组合精密单点定位模糊度解算(PPP-AR);并通过对PPP收敛速度以及定位精度等方面进行分析来评估组合后的定位结果。实验结果表明,在数据观测质量方面,地面观测站同时观测三系统卫星总数可以达到31颗;三系统各频点的多路径误差基本在0.3 m以内,三系统各频点的信噪比基本在37 dB·Hz以上;在采用FCB产品进行PPP-AR方面,定位收敛时间优于11.25 min,东、北、天(E、N、U)3个方向的定位精度分别优于1.5、1.1、4.7 cm;相对于PPP浮点解的结果,三系统组合PPP-AR在定位收敛时间和定位结果方面分别提升21%和20%左右。

In order to further improve the precision and convergence time of global navigation satellite system(GNSS)multi-system combined precision point positioning(PPP),the paper proposed an ambiguity resolution(AR)method for GPS/BDS-3/Galileo PPP:the multi-system phase fraction cycle bias products(FCB)released by Wuhan University and the ionosphere-free PPP model were used to realize the GPS/BDS-3/Galileo three-system combined PPP ambiguity resolution(PPP-AR);and the combined positioning was evaluated in terms of PPP convergence rate and positioning accuracy.Experimental result showed that the ground observation station could simultaneously observe a total of 31 satellites of the three systems in terms of the data observation quality;the multipath error of each frequency of the three systems would be basically less than 0.3 m,and the signal-to-noise ratio of each frequency point of the three systems would be basically better than 37 dB·Hz;for the PPP-AR by using FCB products,the positioning convergence time would be better than 11.25 min,and the positioning accuracy of east(E),north(N)and up(U)directions would be better than 1.5,1.1 and 4.7 cm,respectively;moreover,compared with the result of PPP floating solution,the positioning convergence time and positioning result of the three systems combined PPP-AR could be improved by 21%and 20%,respectively.