摘要
GPS/BDS组合定位综合利用两系统观测值进行定位解算,但GPS系统与北斗系统间存在着系统差异,为了保证组合定位时两系统间数据合理分配,需确定解算时两系统观测值间合理的权比。本文通过对几组不同先验权比时伪距单点定位结果比较选出的最佳权比与利用Helmert方差分量估计方法求得的两个系统伪距单定位权比进行分析,结果表明,GPS/BDS组合定位时的合理的先验权比为1∶1,但在某些时间段内,其中一个系统的卫星数减少或数据质量不佳等情况时,这会导致该系统观测值在组合定位中的贡献率大大降低,此时就需要分段确定合理权比。
GPS/BDS combination positioning is a combination of two systems observa- tions for positioning solution, but the GPS system and the Beidou system there is a systemat- ic difference. In order to ensure the reasonable allocation of data between the two systems, it is necessary to determine a reasonable weight ratio between the observed values of the two systems. The optimal weight ratio is obtained by using the pseudo-range single-point locali- zation of several different a priori weights ratio and the single-position weight ratio of the two systems obtained by using the Helmert variance component estimation method. The results show that the ratio of GPS/BDS combination is 1 ： 1. However, when the number of satel- lites in one system decreases or the data quality is poor, the contribution rate of the system observations in the combined localization is greatly reduced. In this case, it is necessary to determine the reasonable ratio
作者
张广汉
余学祥
严超
卢礼
张计凯
ZHANG Guanghan YU Xuexiang YAN Chao LU Li ZHANG Jikai(School of Geomatics ,Anhui University of Science and Technology, Huainan 232001, China)
出处
《全球定位系统》
CSCD
2017年第3期48-53,共6页
Gnss World of China
基金
国家自然科学基金(批准号:41474026)
关键词
组合定位
HELMERT方差分量估计
先验权比
分段权比
Combined positioning
Helmert variance component estimation
a priori rati- o
segmentation weight ratio
