BDS/GPS精密单点定位收敛时间与定位精度的比较

Convergence Time and Positioning Accuracy Comparison between BDS and GPS Precise Point Positioning

采用武汉大学卫星导航定位技术研究中心发布的北斗精密卫星轨道和钟差,在TriP 2.0软件的基础上实现了BDS PPP定位算法,并利用大量实测数据进行了BDS/GPS静态PPP和动态PPP浮点解试验。结果表明,BDS静态PPP的收敛时间约为80min,动态PPP的收敛时间为100min;对于3h的观测数据,静态PPP收敛后定位精度优于5cm,动态PPP收敛后水平方向优于8cm,高程方向约12cm;与GPS PPP类似,东分量上定位精度较北分量稍差。当前由于BDS的全球跟踪站有限,精密轨道和钟差精度不如GPS,因此BDS PPP的收敛时间较GPS长,但收敛后可实现厘米至分米级的绝对定位。

BDS/GPS data fromMGEX were processed by TriP 2 0. software developed at Wuhan University . Both static and kinematic float PPP are tested by adopting precise satellite orbits and clocks provided by Research Center of GNSS ,Wuhan University .The results show that the convergence time of BDS static PPP is about 80 min while kinematic PPP is about 100 min .For 3 h observations ,static positioning accuracy of 5 cm and kinematic positioning accuracy of 8 cm in horizontal ,about 12 cm in vertical can be achieved . Simil ar to GPS PPP ,precision in east component is worse than north .At present ,BDS PPP needs longer convergence time than GPS PPP to reach an absolute positioning accuracy of cm^dm due to the l ack of global tracking stations and the limited accuracy of orbit and clock products .