基于BDS广播星历的卫星轨道拟合精度分析  

Analysis of Fitting Accuracy of Satellite Orbit Based on BDS Broadcast Ephemeris

作　　者：李振昌 李仲勤 寇瑞雄 LI Zhenchang;LI Zhongqin;KOU Ruixiong(Faculty of Geomatics,Lanzhou Jiaotong University,Lanzhou 730070,China;Gansu Provincial Engineering Laboratory for National Geographic State Monitoring,Lanzhou 730070,China)

机构地区：[1]兰州交通大学测绘与地理信息学院,甘肃兰州730070 [2]甘肃省地理国情监测工程实验室,甘肃兰州730070

出　　处：《全球定位系统》2018年第6期87-91,共5页Gnss World of China

基　　金：兰州交通大学(201806)优秀平台支持

摘　　要：在实时定位导航中,为了提高利用BDS广播星历计算卫星位置的效率,提出将卫星轨道拟合为一个多项式.首先利用切比雪夫多项式拟合法,将拟合时段固定为1h,拟合间隔固定为5min,每30s选取一个检验点,利用不同的拟合阶数,分别对GEO、IGSO、MEO三类不同类型的北斗卫星轨道进行拟合分析;然后将拟合阶数固定为9,利用2～6min的拟合时间间隔,将三类卫星作为整体进行轨道拟合分析.算例表明,只要选取合适的拟合阶数,三类不同类型的北斗卫星轨道拟合精度都较高,拟合误差最大值在厘米级,误差均值在毫米级,满足精度要求;固定9阶拟合多项式时,2～6min时间间隔的拟合精度都可以满足精度需求.切比雪夫多项式拟合法适用于BDS广播星历的卫星轨道拟合.In real-time positioning and navigation,in order to improve the efficiency of calculating the satellite position using the broadcast ephemeris of BDS,it is proposed to fit the satellite orbit to a polynomial.Firstly,using Chebyshev polynomial fitting method,the fitting period was fix to 1 h,the fitting interval was fixed at 5 min,and a checkpoint was selected every 30 s,different fitting orders was used,the Beidou satellite orbits of three different types of geostationary earth orbit,medium earth orbit and inclined geosynchronous orbit was fitted and analyzed.Then,the fitting order is fixed at 9,and the orbits of three types of satellites as a whole is fitted and analyzed using a fitting interval of 2 to 6 minutes..The example shows that as long as the appropriate fitting order is selected,the Beidou satellite orbit fitting accuracy of the three different types of orbits is high.The maximum fitting error is in the centimeter level,and the average error is in the millimeter level,which satisfies the precision requirements.When the fitting polynomial is fixed at the 9 th-order,the fitting accuracy of 2~6 min time interval can meet the precision requirement.The Chebyshev polynomial fitting method is suitable for the fitting of the satellite orbit of BDS broadcast ephemeris.

关 键 词：切比雪夫多项式 BDS广播星历 卫星轨道拟合 精度分析 

分 类 号：P228.4[天文地球—大地测量学与测量工程]