GNSS clock corrections densification at SHAO: from 5 min to 30 s
GNSS clock corrections densification at SHAO: from 5 min to 30 s
复制标题
SHAO 的 GNSS 时钟修正致密化：从 5 分钟到 30 秒
DOI：
10.1007/s11433-013-5181-7
复制
发表时间：
2014-01-01
影响因子：
6.4
通讯作者：
Wu Bin
中科院分区：
文献类型：
--
作者：
Chen JunPing;Zhang YiZe;Wu Bin
高频多GNSS零差应用，如低地球轨道器（LEO）的精确轨道确定（POD）和高频动态定位，需要相应的高速率GNSS时钟校正。在轨道确定过程中，GNSS时钟的确定是耗时的，特别是在GPS/GLONASS组合处理中。目前，大量的IGS分析中心（AC）提供5分钟采样的时钟校正，只有少数AC提供30秒采样的GPS和GLONASS时钟。本文在欧洲轨道确定中心（CODE）时钟确定算法的基础上，采用了一种有效的历元差GNSS时钟确定算法。详细介绍了上海天文台GNSS分析中心的时钟确定过程和算法。结果表明，该方法大大加快了处理速度，和密集的30秒的时钟具有相同的质量为5分钟的时钟估计的基础上的零差的解决方案。将SHAO提供的30秒GNSS加密钟与IGS及其AC的30秒GNSS加密钟进行比较，结果表明，我们的30秒GNSS加密钟与IGS的30秒GNSS加密钟具有相同的质量。Allan偏差也给出了同样的结论。在运动PPP和LEO POD中对SHAO 30-s时钟产品进行了进一步验证。结果表明，使用SHAO 30-s GNSS时钟和IGS（及其AC）终端时，位置具有相同的精度。算法和处理方法的鲁棒性确保其扩展以提供5-s甚至更高频率的时钟。新方法的实施很简单，可以作为当前科学软件包的黑盒交付。
High frequency multi-GNSS zero-difference applications like Precise Orbit Determination (POD) for Low Earth Orbiters (LEO) and high frequency kinematic positioning require corresponding high-rate GNSS clock corrections. The determination of the GNSS clocks in the orbit determination process is time consuming, especially in the combined GPS/GLONASS processing. At present, a large number of IGS Analysis Centers (AC) provide clock corrections in 5-min sampling and only a few ACs provide clocks in 30-s sampling for both GPS and GLONASS. In this paper, an efficient epoch-difference GNSS clock determination algorithm is adopted based on the algorithm used by the Center for Orbit Determination in Europe (CODE). The clock determination procedure of the GNSS Analysis Center at Shanghai Astronomical Observatory (SHAO) and the algorithm is described in detail. It is shown that the approach greatly speeds up the processing, and the densified 30-s clocks have the same quality as the 5-min clocks estimated based on a zero-difference solution. Comparing the densified 30-s GNSS clocks provided by SHAO with that of IGS and its ACs, results show that our 30-s GNSS clocks are of the same quality as that of IGS. Allan deviation also gives the same conclusion. Further validation of the SHAO 30-s clock product is performed in kinematic PPP and LEO POD. Results indicate that the positions have the same accuracy when using SHAO 30-s GNSS clocks or IGS (and its AC) finals. The robustness of the algorithm and processing approach ensure its extension to provide clocks in 5-s or even higher frequencies. The implementation of the new approach is simple and it could be delivered as a black-box to the current scientific software packages.