不同GNSS在高纬度地区时间传递性能分析

全球卫星导航系统（GNSS）载波相位时间传递技术是高精度时间传递领域的主要研究方法之一，但目前关于该部分的研究主要集中在中低纬度地区，在高纬度地区并不多见。不同GNSS由于星座设计不同，在高纬度地区结构差异较大，因此需要对不同GNSS在高纬度地区的时间传递性能进行分析。实验结果表明，在高纬度地区时间传递中，Galileo稳定度最高，GPS和BDS次之，GLONASS最差。同时因在高纬度地区卫星的高度角普遍偏低，为合理平衡低高度角时可视卫星多和多路径误差大的矛盾，对不同截止高度角下获取的链路时间传递性能进行了分析。结果表明，在5°截止高度角下，高纬度地区的时间传递链路稳定性最好。

Analysis of time transfer performance of different-GNSS in high-latitude regions

The global navigation satellite system(GNSS) carrier-phase time transfer technology is one of the crucial research methods in the field of precise time transfer, but currently, research on this part is mainly concentrated in the middle to low latitude regions, and is not common in high-latitude regions. Due to different constellation designs, different-GNSS structures vary greatly in high-latitude regions. Therefore, it is necessary to analyze the time transfer performance of different GNSS in high latitude regions.The experimental results indicate that in high-latitude regions, Galileo has the highest stability in time transfer, followed by GPS and BDS, and GLONASS has the worst one. At the same time, due to the generally low elevation angles of satellites in high-latitude regions, in order to balance the contradiction between multiple visible satellites and large multipath error in low elevation angles, the time transfer performance of links obtained under different elevation cutoff angles is analyzed. The results show that at a 5° elevation cutoff angle, the stability of time transfer links in high-latitude regions is the best.