利用非差观测量估计北斗卫星实时精密钟差

Real-Time Precise BDS Clock Estimation with the Undifferenced Observation

研究并实现了基于非差观测量的北斗卫星实时钟差估计算法，利用全球53个多模全球导航卫星系统（global navigation satellite system，GNSS）实验跟踪网（multi—GNSS experiment，MGEX）站的北斗与全球定位系统（global positioning system，GPS）观测数据进行实时钟差估计，分析了实时钟差产品的精度与定位性能。多天统计结果表明，本文生成的GPS实时钟差与事后钟差符合较好，精度优于0．07ns，略低于事后钟差产品，验证了基于非差观测量的实时钟差估计软件的处理精度。本文解算的北斗实时钟差的精度为0．1～0．15ns，略低于GPS卫星。基于实时钟差进行模拟动态精密单点定位（precise point positioning，PPP）实验，北斗与GPS在水平方向的定位精度为0．041m和0．058m，高程方向的精度为0．069m和0．037m，定位结果分别与事后钟差解算的结果符合较好，表明实时钟差与事后钟差差异不大。

We studied and implemented an algorithm for real-time precise satellite clock estimation based on the undifferenced code and phase observations. The BDS and GPS observations of 53 MGEX global sites were collected to generate the real-time clock that was compared with the final WHU 30 s precise clock product. The accuracy of our real-time GPS clock was better than 0.06 ns, comparable to that of the IGS final clock products, which verifies the processing accuracy of our software. The ac- curacy of the real-time BDS clock was 0.1-0.15 ns, a little worse than that of GPS satellites. A kine- matic PPP test showed that, the horizontal accuracy of BDS solution was about 0. 041 m, comparable to 0. 058 m of GPS solution, while the vertical accuracy is 0. 069 m, a slightly worse than 0. 037 m of GPS. The kinematic PPP solution based on the real-time clock correction was consistent with the solu- tion based on the final clock products, which verifies the real-time clock products.