HY-2B星载GPS数据质量及简化动力学精密定轨分析

对HY-2B卫星星载GPS数据进行质量检查，分析伪随机脉冲先验值对简化动力学精密定轨的影响。结果发现，在所有时间间隔中，先验标准差为1×10^-8 m/s²时定轨精度最高，最优伪随机脉冲时间间隔为6 min。估计天线相位中心变化（PCV），分析不同分辨率（10°×10°、5°×5°）PCV模型对定轨结果的影响，并使用载波相位残差、重叠轨道比较和SLR检核对定轨结果进行检验。结果表明，99%以上的历元能观测到4颗以上GPS卫星，数据完整率达到99.65%，L1、L2波段的多路径误差RMS均值分别为15.7 cm、9.5 cm，证明HY2国产接收机性能良好。轨道内符合精度均达到cm级；未加PCV模型时，SLR检核RMS值为27.8 mm，加入10°×10°、5°×5° PCV模型后，SLR检核RMS值分别提高0.9 mm和1.2 mm，说明轨道外符合精度也达到cm级。

Analysis of HY-2B Onboard GPS Data Quality and Reduced-Dynamic Precise Orbit Determination

In this paper, we check the quality of the HY-2B onboard GPS data, and analyze the influence of the pseudo-random pulse prior value on the reduced-dynamic precision orbit determination. At all time interval, when the prior standard deviation is 1×10^-8 m/s², the orbit determination accuracy is the highest, and the optimal pseudo-random pulse interval is 6 minutes. This study estimates the antenna phase center variations(PCV) and analyzes the influence of different resolution PCV(10°×10°, 5°×5°) models on the orbit determination results through phase residual, overlapping orbit comparison and SLR. The experimental results show that more than 4 GPS satellites can be observed in over 99% of the epochs, data integrity rate reaches 99.65%, and average RMS of multipath errors of the L1 and L2 bands are 15.7 cm and 9.5 cm respectively, proving the good performance of the domestic HY2 receiver. The orbit accuracy of internal validation reaches the centimeter level. The SLR verification RMS value is 27.8 mm without PCV model. After adding the 10°×10°, 5°×5° PCV models, the SLR verification RMS values improve 0.9 mm and 1.2 mm, respectively. The orbit accuracy of external validation also reaches the centimeter level.