GPS/VRS网络实时精密轨道改正算法研究

ON REAL-TIME PRECISE ORBIT BIASES CORRECTION TECHNIQUE FOR GPS/VRS NETWORK

分析了卫星轨道误差对于GPS/VRS网络的影响,并利用IGS精密预报星历和GPS广播星历信息,提出了一种适用于GPS/VRS区域参考站网络的VRS精密轨道实时改正数法。基于四川GPS连续运行参考站网络(SGRSN)和南加州集成GPS观测网络(SCIGN)实测数据的分析表明,与现有常规网络内插轨道改正方法相比,新方法具有更高的轨道误差改正精度,相对改正理论精度优于0.004×10-6,使轨道误差对100km以内的RTK定位影响为亚毫米级,适用于GPS/VRS网络厘米级动态RTK定位的精密轨道误差改正。

An analysis of influence from the uncorrected satellite orbit errors on the GPS/VRS network based positioning is carried out. A precise real-time method for using the IGS ultra rapid products （IGU） and the GPS broadcast ephemeris to calculate the VRS orbit corrections is presented which is suited for the real-time correction of precise orbit of VRS in GPS/VRS reference station network based positioning. Test data acquired from both the SGRSN （Sichuan GPS Reference Station Network） and SCIGN （Southern California integrated GPS network） are used to evaluate the performance of the modeling techniques. The new method is proved to be more precise and reliable as compared with the existing conventional network-based orbit error interpolation method. It is shown that 0.004×10^-6 relative accuracy is reached, i.e. the influence from the orbit bias for the RTK positioning within 100km area can be of sub-millimeter level.