BDS-2与BDS-3卫星空间信号精度评估

Accuracy assessment of BDS-2 and BDS-3 satellite signal-in-space

针对BDS-3现有卫星空间信号精度评估问题,该文以BDS-2和BDS-3卫星为研究对象,介绍了BDS卫星空间信号精度评估的方法,基于MGEX发布的2019-05-01—2019-05-31日连续31d的广播星历与WUM分析中心的精密星历产品对33颗BDS卫星的轨道误差、卫星钟差、用户测距误差(URE)和空间信号测距误差(SISRE)进行精度评估。研究结果表明:BDS-2中,IGSO与MEO的轨道精度优于GEO,径向精度优于切向和法向;星载钟差均值优于12.1ns;URE和SISRE均值分别优于1.0和1.2m;BDS-3MEO卫星轨道径向、切向、法向均值分别优于0.2、0.8、0.4m,径向和法向比BDS-2 MEO分别提高45.8%与21.1%;BDS-3卫星星载钟差均值优于7.7ns,比BDS-2提高36.2%;BDS-3的URE和SISRE均值分别优于0.6和0.5m,比BDS-2分别提高42.9%和47.4%。

Aiming at the problem on the accuracy assessment of signal-in-space for BDS-3 existing satellites,this paper focused on BDS-2 and BDS-3 satellites,and introduced the method of accuracy assessment for BDS satellite signal-in-space.The accuracy of satellite orbit error,clock error,user range error(URE)and signal-in-space range error(SISRE)for 33 BDS satellites were evaluated based on successive 31 days broadcast ephemeris data of multi-GNSS experiment(MGEX)and precise ephemeris products of Wuhan university multi-GNSS(WUM)during 2019-05-01—2019-05-31.The results showed that:in BDS-2,the orbital accuracy of inclined geosynchronous orbit(IGSO)and medium earth orbit(MEO)was better than that of geostationary earth orbit(GEO),the accuracy of radial orbit error was better than that of tangential and normal;the mean on-orbit satellite clock error was better than 12.1 ns;the mean URE and SISRE were better than 1.0 and 1.2 m,respectively.The mean of radial,tangential and normal orbit error of the BDS-3 MEO were respectively better than 0.2,0.8 and 0.4 m,and the accuracy of radial and normal were increased by 45.8%and 21.1%compared with the BDS-2 MEO.The mean on-orbit satllite clock error of the BDS-3 was better than 7.7 ns,which was improved by 36.2%compared with the BDS-2.The mean URE and SISRE of the BDS-3 were better than 0.6 and 0.5 m,respectively,which were improved by 42.9%and 47.4%compared with the BDS-2.