区域参考站网支撑的PPP和RTK一体化服务及其性能

Abstract

GNSS区域参考站网可为大范围PPP和RTK终端用户提供快速精密定位服务, 然而不同技术体制下的误差影响因素及服务模式不同, 服务端数据处理方法及终端定位性能也会有所差异。本文在实现参考站非差模糊度固定的基础上, 给出了基于区域参考站网的PPP及RTK一体化服务方法, 并对两种技术体制的终端定位效果进行了全面评估。采用西北某省站间距约100 km的CORS站网数据进行试验分析, 结果表明, 采用区域参考站网解算的整数钟/UPD产品进行PPP固定解动态定位时精度较高, 水平方向RMS可达0.5 cm, 区域大气改正数可以显著提升定位终端的初始化速度, 对于PPP和RTK, 60.0%和87.7%的时段单历元即可得到固定解。需要注意的是, 基于VRS模式的RTK定位等价于大气强约束, 在大气建模精度较差时定位精度会显著下降, 而采用虚拟大气约束的PPP-RTK定位精度几乎不受影响。

Alternate abstract:

The GNSS regional reference station network can provide fast and precise positioning services for PPP and RTK users over the wide range. However, for different technical systems, the error influencing factors and service modes are different, the data processing methods at the server and the performance at positioning terminal will also vary. After fixing non-difference ambiguity of the reference station, this paper presents an integrated service method of PPP and RTK based on the regional reference station network, and comprehensively evaluates the terminal positioning performance for these two technologies. Experimental analysis are conducted by using CORS station network data with a station spacing of about 100km in a northwestern province. Results shows the positioning accuracy of PPP fixed solution using the integer clock/UPD product solved by the regional reference station network are very high, and the positioning error in horizontal direction can be less than 0.5 cm. The regional modeled atmospheric can significantly increase the initialization speed of the positioning terminal. For PPP and RTK, a fixed solution can be obtained in a single epoch of 60.0% and 87.7%. It should be noted that the RTK positioning based on the VRS mode is equivalent to strong atmospheric constraints. When the accuracy of modeling atmospheric delay is poor, the positioning accuracy will be significantly reduced, while the PPP-RTK positioning accuracy using virtual atmospheric constraints is almost unaffected.