摘要
利用广播星历计算导航卫星的速度向量是GNSS高精度实时测速的必要条件.本文分析了仅以卫星位置向量为观测量的北斗广播星历的速度计算精度.从广播星历拟合过程出发,推导了北斗18参数模型的速度向量计算公式.基于北斗13颗在轨卫星一年的实际轨道数据,分析了全年广播星历计算卫星速度向量的精度.结果表明,利用18参数模型计算的速度误差最大在10^(-4)m·s^(-1)量级;在相同拟合时段条件下,地球静止轨道(GEO)和倾斜地球同步轨道(IGSO)卫星的速度精度相当,高于中圆地球轨道(MEO)卫星.通过对位置残差序列分析,得出位置残差误差较小且变化趋势平稳是广播星历计算速度精度较高的原因.分析和计算结果验证了仅用位置观测量拟合北斗广播星历算法的有效性.
Using broadcast ephemeris to calculate the velocity vector of navigation satellites is a necessary condition for GNSS real-time velocity determination. In this paper, the accuracy of velocity vector calculated by Beidou broadcasting ephemeris only with position observations is analyzed, and the calculation formula of velocity vector with Beidou 18-element model is deduced. Based on one year data of 13 Beidou satellites in orbit, the accuracy of velocity vector calculated by broadcasting ephemeris is obtained. The results show that the maximal velocity error calculated by the 18-element model is in the order of 10^（-4）m·s^（-1）. At the same fitting period, the velocity accuracy of GEO and IGSO satellites is higher than that of MEO. By analyzing position residual sequence, the conclusion is drawn that the velocity accuracy computed by broadcast ephemeris is very high because of little position residual with smooth change trend. The analysis and calculation results in this paper verify the effectiveness of fitting BDS broadcast ephemeris only using position observations.
作者
常志巧
胡小工
时鑫
栗靖
马勇波
董文丽
邵佳妮
CHANG Zhiqiao;HU Xiaogong;SHI Xin;LI Jin;MA Yongbo;DONG Wenli;SHAO Jia＇ni(Beijing Satellite Navigation Center,Beijing 100094;Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030)
出处
《空间科学学报》
CAS
CSCD
北大核心
2018年第4期553-559,共7页
Chinese Journal of Space Science
基金
国家自然科学基金项目(41204022
41574029
41274043)
上海市空间导航与定位技术重点实验室基金(ZZXT_201701)共同资助
关键词
北斗卫星导航系统
广播星历
18参数模型
位置
速度
BDS （BeiDou Navigation Satellite System）
Broadcast ephemeris
18-element model
Position
Velocity
