选取全球范围内分布的76个IGS服务站的观测数据,采用RTKLIB、gLAB和G-NUT 3个开源精密单点定位(PPP)软件进行静态模拟动态PPP解算。将不同软件解算的对流层延迟和坐标与IGS提供的参考值进行比较,评估其对流层解算精度、收敛时间以及收敛后的坐标解算精度的差异。结果表明:1)不同软件均可解算得到cm级对流层解算精度,其中RTKLIB的解算精度优于1cm;2)对于坐标解算而言,G-NUT需要较长时间才能收敛到指定的精度;而收敛后不同软件均可获得cm级的坐标解算精度,其中RTKLIB解算精度最优,但由于数据预处理策略不完善,会导致部分测站产生较大偏差;G-NUT水平方向解算精度与RTKLIB相当,高程方向稍差;gLAB水平方向解算精度较差,高程方向优于G-NUT。
In this paper, RTKLIB, gI.AB and G-NUT open source precise point positioning software programs are used to process the 76 IGS stations by the use of static simulation of dynamic method in PPP models. The tropospheric delay and the position calculation results are compared with the reference coordinates and tropospheric product from IGS. The results show that standard deviation of troposphere calculated using different software can achieve cm-level accuracy, while RTKLIB can achieve STD better than 1 cm. In terms of coordinate accuracy, G-NUT needs longer convergence time than RTKLIB and gLAB to reach an absolute positioning accuracy. However, all three open-source soft-ware programs can achieve cm-level accuracy using kinematic positioning. Although the incomplete data preprocessing strategy in RTKLIB will cause a greater deviation in some stations, it can still get the highest accuracy; G-NUT has the same accuracy with RTKLIB horizontally, but the vertical resultsare poor. gLAB gets the largest deviations horizontally, but vertical accuracy is better than G-NUT.