顾及微环境气象因子不一致性的对流层延迟精细建模

Since the meteorological parameters distribution inconsistency in complex terrain region is not fully considered, the existing tropospheric delay model can't meet the needs for high frequency fine observation in some key or special area (such as the river valley region where high speed railway bridge and hydropower dam were built, the mountain area where radio telescope were built). In these specific small region, the meteorological and geographical environment, such as weather conditions, natural landforms, surface cover, and so on, are defined as micro environments. In order to overcome the limitation of the spatial resolution of the existing tropospheric delay model in micro environment, the project will use the ground-based GNSS network observation technology to establish the micro environment high spatial resolution tropospheric delay model. By analyzing the factors which restrict the modeling accuracy of the inhomogeneous distribution of troposphere delay, the modeling of temporal and spatial distribution of meteorological factors in micro environment, the high accuracy estimation of GNSS network inhomogeneous tropospheric delay, and the precise modeling of tropospheric delay considering the heterogeneity of the micro environmental meteorological factors will be studied. Finally, a complete set of techniques for the tropospheric delay fine modeling in the micro environment is established, which lays the foundation for the research and application of GNSS small scale fine observation and the evolution of troposphere in micro environment.

由于未充分考虑复杂地形区域内气象参数分布的不一致性，现有对流层延迟模型无法较好满足一些重点或特殊区域（如：高速铁路桥梁、水电枢纽大坝所处的河流峡谷区域，射电望远镜所在的群山区域等）进行高频精细观测的误差改正需求。在这些特定的小尺度区域内，将其天气条件、自然地貌、地表覆盖等气象与地理环境构成定义为微环境。针对现有对流层延迟模型在微环境中空间分辨率不足的缺陷，项目利用地基GNSS网络观测技术，建立微环境高空间分辨率的对流层延迟精细化模型。通过分析制约微环境对流层延迟不均匀分布模型建模精度的各项因素，研究微环境气象因子时空分布的模型建模、GNSS网络不均匀对流层延迟的高精度估计，以及顾及微环境气象因子不一致性的对流层延迟精细建模。最终形成基于GNSS的微环境对流层延迟精细建模的成套技术，为GNSS小尺度精细观测和微环境对流层时空演变等相关研究与应用奠定基础。

由于未充分考虑复杂地形区域内气象参数分布的不一致性，现有对流层延迟模型无法较好满足高速铁路桥梁、水电枢纽大坝所处的河流峡谷区域，射电望远镜所在的群山区域等特殊区域进行高频精细观测的误差改正需求。项目通过分析制约微环境对流层延迟不均匀分布模型建模精度的各项因素，研究了微环境气象因子时空分布的模型建模、GNSS网络不均匀对流层延迟的高精度估计，最终形成了基于GNSS的微环境对流层延迟精细建模的数据处理技术。提出的MGF数据预处理方法，数据解算效率提升了100倍。试验结果表明，大气异常情况下，小尺度的对流层延迟RMS可达到5mm量级。