An evaluation of real-time troposphere estimation based on GNSS Precise Point Positioning
An evaluation of real-time troposphere estimation based on GNSS Precise Point Positioning
复制标题
基于GNSS精密单点定位的实时对流层估计评估
DOI：
10.1002/2016jd025727
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发表时间：
2017-03-16
影响因子：
4.4
通讯作者：
Yuan, Yunbin
中科院分区：
文献类型：
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作者：
Ding, Wenwu;Teferle, Felix Norman;Yuan, Yunbin
预计通过纳入全球定位系统、全球轨道导航卫星系统、伽利略和北斗等多个全球导航卫星系统的观测，可进一步提高实时全球导航卫星系统气象学的性能。本文建立了一个利用改进的GPS和零差模糊度解算演示器（PPP-WIZARD）提取天顶对流层延迟（ZTD）的实用RT系统。全球导航卫星系统（包括全球定位系统、全球轨道导航卫星系统和伽利略系统）的观测数据流使用基于国家空间研究中心RT卫星轨道/时钟产品的RT精确单点定位战略进行处理。进行了为期30天的实验，处理了分布在全球的20个台站的观测数据流。对使用单系统和多系统观测的RT对流层结果的初始化时间和精度进行了评价。并对PPP模糊度解算的效果进行了评价。结果表明，基于单系统观测资料的RT对流层估计都可以应用于天气临近预报，其中GPS方案优于GLONASS方案。还可以通过PPP模糊度解算和利用GNSS观测来提高性能。具体来说，我们注意到，模糊度的解决是更有效地提高ZTD的精度，而初始化过程可以更好地加速GNSS观测。结合所有技术，在大约8.5分钟的初始化过程之后，可以实现在ZTD中具有大约8 mm的平均精度的RT对流层结果，这证明了用于RT气象应用的GNSS观测和模糊度解算的上级结果。
It is anticipated that the performance of real-time (RT) GNSS meteorology can be further improved by incorporating observations from multiple Global Navigation Satellite System (GNSS), including GPS, GLONASS, Galileo, and BeiDou. In this paper, an operational RT system for extracting zenith troposphere delay (ZTD) using a modified version of the Precise Point Positioning With Integer and Zero-difference Ambiguity Resolution Demonstrator (PPP-WIZARD) was established. GNSS, including GPS, GLONASS, and Galileo, observation streams were processed using RT Precise Point Positioning (PPP) strategy based on RT satellite orbit/clock products from the Centre National d'Etudes Spatiales. An experiment covering 30 days was conducted, in which the observation streams of 20 globally distributed stations were processed. The initialization time and accuracy of the RT troposphere results using single-system and multisystem observations were evaluated. The effect of PPP ambiguity resolution was also evaluated. Results reveal that RT troposphere estimates based on single-system observations can both be applied in weather nowcasting, in which the GPS-only solution is better than the GLONASS-only solution. The performance can also be improved by PPP ambiguity resolution and utilizing GNSS observations. Specifically, we notice that ambiguity resolution is more effective in improving the accuracy of ZTD, whereas the initialization process can be better accelerated by GNSS observations. Combining all techniques, the RT troposphere results with an average accuracy of about 8 mm in ZTD can be achieved after an initialization process of approximately 8.5 min, which demonstrates superior results for applying GNSS observations and ambiguity resolution for RT meteorological applications.