Research on a method of real-time combination of precise GPS clock corrections
Research on a method of real-time combination of precise GPS clock corrections
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一种GPS精密时钟改正实时组合方法研究
DOI：
10.1007/s10291-016-0515-3
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发表时间：
2016
期刊：
影响因子：
4.9
通讯作者：
Guo Hailin
中科院分区：
文献类型：
--
作者：
Chen Liang;Song Weiwei;Yi Wenting;Shi Chuang;Lou Yidong;Guo Hailin
实时获取卫星轨道和时钟修正对于实时PPP是必要的。有九个国际全球导航卫星系统服务(IGS)分析中心(分析中心)提供实时卫星轨道和时钟产品。考虑到网络传输、观测数据和解算方法的影响，单个交流产品容易出现停电和离群点。实时数据流的组合是改善这些问题的有效方法。对于单个交流解算中的异常数据，我们重点研究了一种组合方法。提出了参数分离、权重估计和异常处理等处理技术。实验结果表明，与单一交流时钟和IGS01和IGS02产品相比，采用上述方法得到的组合(简单梳理后)时钟校正中的不可用和异常频率有所降低。IGS01是欧洲航天局(ESA)提供的单历元组合产品。IGS02是由联邦地图和大地测量局(BKG)提供的卡尔曼滤波组合产品。在为期7天的试验期内，还检查了实时产品的可用性和准确性的性能。梳子的可用性高达99.9%，优于单一AC和IGS01、IGS02产品。Comb的精度标准差为0.15 ns，与国家空间研究中心(CNES)产品持平，但比德国航空航天中心(DLR)、欧空局、GeoForschungsZentum(GFZ)、IGS01和IGS02产品高40、17、29、42和32%。应用梳状产品的三维定位精度以均方根(RMS)计算为9.10 cm，分别比使用CNES、DLR、ESA、GFZ、IGS01和IGS02产品的定位精度高41、44、5、43、43和42个百分点。结果表明，该方法得到的梳状时钟实时校正值比单交流校正器和IGS01、IGS02产品更稳定可靠。
The acquisition of real-time satellite orbit and clock corrections is necessary for real-time PPP. There are nine International GNSS Service (IGS) analysis centers (ACs) that provide real-time satellite orbit and clock products. Given the influence of network transmission, observation data and solution methods, a single AC product suffers from outages and outliers. A combination of real-time data streams is an effective method of improving these problems. We focus on a combination method with regard to anomalous data in a single AC solution. Processing techniques such as parameter separation, weight estimation and exception handling are proposed. Experimental results indicate that, after the process, the frequency of unavailability and anomaly in the combined (simply COMB later) clock correction obtained using the above-mentioned method decreases relative to that of a single AC and IGS01 and IGS02 products. IGS01 is a single-epoch combined product provided by European Space Agency (ESA). IGS02 is a Kalman filter combined product provided by the Federal Agency for Cartography and Geodesy (BKG). In a 7-day experimental period, the performance of real-time products is also examined regarding availability and accuracy. The availability of COMB is as high as 99.9 %, which is superior to that of single AC and IGS01 and IGS02 products. The accuracy of COMB is 0.15 ns in standard deviation, which is at the same level as the Centre National d’Etudes Spatiales (CNES) product, but higher by 40, 17, 29, 42 and 32 % than that of the German Aerospace Center (DLR), ESA, GeoForschungsZentrum (GFZ), IGS01 and IGS02 products. The 3D positioning accuracy applying COMB product is 9.1 cm in root mean square (RMS), which is higher by 41, 44, 5, 43, 43 and 42 % than applying CNES, DLR, ESA, GFZ, IGS01 and IGS02 products, respectively. The results demonstrate that the real-time COMB clock correction obtained by the method proposed is more stable and reliable than single AC and IGS01 and IGS02 products.