不同截止高度角多模GNSS组合单点定位性能分析  

Performance Assessment of Multi-GNSS Single Point Positioning with Different Cut-Off Elevation Angles

作　　者：徐龙威[1] 刘晖[1] 张明[1] 钱闯[1] 舒宝 

机构地区：[1]武汉大学卫星导航定位技术研究中心,武汉市珞喻路129号430079

出　　处：《大地测量与地球动力学》2015年第6期987-991,共5页Journal of Geodesy and Geodynamics

基　　金：国家交通运输部2013年信息化重大专项

摘　　要：讨论多模GNSS时空统一方法,建立多模单点定位数学模型。采用8个测站的实测数据,对比单GPS与GPS/GLONASS/BDS/Galileo四大GNSS组合多模系统在截止高度角分别为15°、30°、45°时的单点定位性能。结果表明,15°时,多模较单GPS定位精度有一定改善,但效果不明显;30°、45°时,单GPS不能实现实时定位,多模则能提供稳定可靠的实时定位结果。在北斗卫星导航系统可见卫星数较多的亚太区域,95%以上历元可用,水平方向偏差RMS<8m,高程方向偏差RMS<20m,对城市峡谷和密林中导航具有一定的参考价值。Along with the growth of GNSS, the number of GNSS satellites isalso increasing. The combina- tion of different GNSS satellites could guarantee improved satellite availability. In this paper, unifying multi- GNSS time system is analyzed. Further, a coordinate system and a multi-GNSS single point （SPP） positio- ning model and a method of determining the weight matrix for multi-GNSS are implemented. The perform- ance of the combined GPS/GLONASS/BDS/Galileo SPP is assessed using the observations from 8 GNSS sta- tions. The position performance is compared between standalone GPS and multi-GNSS with 15°, 30°and 45° cut-off elevation angles. The results show that 15° cut-off elevation angle satellite availability is best, and that multi-GNSS advances positioning accuracy only a little. When cut-off elevation angle is 30°or 45°, the satellite availability is worse; standalone GPS is often unable to ensure continuous and accurate positioning due to lack of available satellites, but multi-GNSS still could guarantee the continuity and integrity of real time positio- ning. In the BDS coverage area, the rate of epochs that can be used for locationis over 95% ,and the horizontal direction error is less than 30 m. This paper has reference value for navigation in complex environments, such as an urban environments and thick forests.

关 键 词：时间系统 系统融合 多模GNSS单点定位 截止高度角 定位精度 

分 类 号：P228[天文地球—大地测量学与测量工程]