多系统融合单点定位先验和验后定权研究  

Research on a priori and posterior weighting methods for Multi-GNSS combined single point positioning

作　　者：张哲浩 潘林[1,2] ZHANG Zhehao;PAN Lin(School of Geoscience and Info-Physics,Central South University,Changsha 410083,China;Guangxi Key Laboratory of Spatial Information and Geomatics,Guilin 541004,China)

机构地区：[1]中南大学地球科学与信息物理学院,长沙410083 [2]广西空间信息与测绘重点实验室,广西桂林541004

出　　处：《全球定位系统》2021年第3期1-6,共6页Gnss World of China

基　　金：国家自然科学基金项目(41904030);湖南省自然科学基金项目(2020JJ5706);广西空间信息与测绘重点实验室资助课题(19-050-11-09)。

摘　　要：针对多模全球卫星导航系统(GNSS)融合伪距单点定位随机模型难以精确构建的问题,在全球范围内选取了10个多GNSS实验跟踪网MGEX(Multi-GNSS Experiment)观测站连续7天的观测数据,将四大GNSS系统的观测值分为五类,比较了高度角模型、用户等效测距误差(UERE)模型及验后Helmert方差分量估计模型的伪距单点定位精度.结果表明:在四系统融合伪距单点定位时,Helmert方差分量估计模型能提高定位精度,高度角模型定位精度优于UERE模型,其中基于高度角的Helmert方差分量估计模型结果最优.When using multi-system code observations to conduct the pseudo range single point positioning,a reasonable stochastic model needs to be determined.In this paper,the datasets from ten multisystem stations MGEX(Multi-GNSS Experiment)on seven consecutive days are selected to compare the positioning performance of pseudo range single point positioning with the elevation-dependent model and the user equivalent range error(UERE)model,as well as the posterior Helmert variance component estimation model based on the two a priori models.The observations from the four Global Navigation Satellite Systems(GNSS)are divided into five groups.The results show that the positioning accuracy can be improved when adopting the Helmert variance component estimation model.The positioning accuracy of the elevationdependent model is better than that of the UERE model.The Helmert variance component estimation model based on the elevation-dependent weighting strategy achieves the best positioning performance.

关 键 词：多系统组合 随机模型 伪距单点定位 HELMERT方差分量估计 先验定权 

分 类 号：P228.4[天文地球—大地测量学与测量工程]