为了基于多GNSS观测获取高精度电离层延迟，以构建精细电离层延迟模型和异常扰动预警机制。本项目拟研究基于多GNSS系统伪距、相位观测，采用精密单点定位(Precise Point Positioning, PPP)技术进行快速、高效的高精度电离层延迟估计方法、策略，增强、提升电离层延迟和模型的精度；分析、研究多GNSS对应电离层延迟的一致性和补偿算法及其最优融合处理方法，以提高估计参数的精度；研究电离层异常扰动的触发机制，构建电离层异常值函数模型，实现对电离层异常扰动发生时刻、持续时间、发生源地点和级别评估四要素的精确监测和预报。通过系统、全面地比对和评估，实现多GNSS高精度电离层延迟的估计和精细模型的建立及其扰动预警、预报，为高精度导航定位、灾害监测和空间科学研究提供理论支持与技术保障。

In order to build more refined ionospheric delay model and early warning anomalous disturbance mechanism, high-precision ionospheric delay need to be obtained using GNSS observation. Based on pseudorange and phase observation of multi-GNSS network, the rapid, efficient ionospheric delay is estimated by PPP(Precise Point Positioning) technology in this project, thus ionospheric delay and model precision is improved; To improve the precision of solution parameters, the consistency of ionospheric dealy, corresponding compensation algorithm and the optimal fusion method are studied and analyzed; Combined with ionospheric anomalous disturbances triggering mechanism research, then built the function model of ionospheric outliers, the trigger time, the last time, disturbances epicenter and magnitude of ionospheric anomalous disturbances can be accurately monitored and forecasted. Refined modeling, forecasting and early warning of high precision ionospheric dealy using multi-GNSS data can be completely compared and evaluated, the project provide theoretic and technical support for precision positioning, disaster monitoring and space science.