融合多模GNSS/长期验潮站数据建立中国沿海高精度高分辨率海潮负荷位移模型研究

Due to the limitations of existing theories and technical conditions, the accuracy of global ocean tide models in coastal area is low, which seriously affects the precision of the regional ocean tide loading correction. With the rapid development of Global Navigation satellite system (GNSS) and the increase of GNSS base stations and tide gauge stations, a new idea is provided for establishing ocean tide loading displacement (OTLD) model. GNSS technology has the advantage of global coverage and high spatial resolution for establishing OTLD model, but its system error and coupling effect can easily reduce the modeling accuracy. Meanwhile, tide gauge stations have the long-term tide observations with high precision and high sample rate, but their sparse distribution is difficult to meet the requirements of high resolution modeling. Based on this, establishing high-precision and high-resolution OTLD model based on fusion of Multi-Constellation GNSS and tide gauge observations is studied in this project. Firstly the model of estimation OTLD based on GNSS precise point positioning are established and the GNSS errors are eliminated with high precision. Secondly, in order to eliminate the system errors and coupling effect of GNSS, the tide gauge results are taken as priori information constraint in GNSS to determine OTLD. In the end the adaptive OTLD model and algorithm which fusing the GNSS and tide gauge observations are proposed. The high precision and high resolution coastal OTLD model is established which can provide technology service guarantee for high precision ocean tide loading correction.

受现有理论与技术条件限制，全球海潮模型在近海精度较低，严重影响区域海潮负荷效应改正精度。随着全球导航定位技术（GNSS）的快速发展、GNSS基准站及验潮站数量的增加，为构建海潮负荷位移模型提供了新思路，其中GNSS技术建立海潮负荷位移模型具有全球覆盖及高空间分辨率的优势，但其系统误差及耦合效应易降低建模精度；同时长期验潮站具备高精度、高采样率的潮汐观测，但其分布稀疏难以满足高分辨率建模的需求。基于此，本课题拟联合多模GNSS与验潮站进行优势互补建立沿海高精度高分辨率海潮负荷位移模型。首先建立多模GNSS海潮负荷位移估计模型并高精度消除误差项，其次将验潮站结果作为GNSS先验信息约束反演海潮负荷位移以改善GNSS技术的系统误差与耦合效应；研究融合验潮站/多模GNSS数据自适应的海潮负荷位移模型和方法，构建适应近海地区的高精度高分辨率海潮负荷位移模型，为高精度海潮负荷效应改正提供技术服务保障。

海潮负荷效应的影响对目前精度要求越来越高的大地测量数据处理而言，特别是对于近海区域高精度定位已成为不容忽视的重要影响因素之一。当前对于海潮负荷效应的研究主要是利用全球海潮模型予以修正，但现有全球海潮模型在公海区域精度较高，而在近海区域精度较差，从而影响了全球海潮模型的整体精度。因此，为有效提高定位精度，迫切需要构建高精度的海潮模型。随着全球导航卫星系统GNSS（Global Navigation Satellite System）的快速发展及验潮站数量的不断增多，联合多模GNSS与长期验潮站监测海潮负荷位移变化为获取沿海区域高精度高分辨率海潮负荷位移模型的有效手段，为此，项目开展了基于多模GNSS观测估计海潮负荷位移的方法研究，为高精度反演海潮负荷位移提供了新思路与方法；研究了附有验潮站先验信息约束的GNSS观测估计海潮负荷位移的模型和算法，为GNSS系统误差校正提供了新途径；联合多模GNSS与验潮站数据建立了海潮负荷位移自适应融合模型，既有效提高了GNSS的反演精度，又弥补了验潮站分布稀疏的局限，为高精度高分辨率近海海潮负荷位移模型的构建提供了服务与保障。