基于实时Kalman滤波的电离层建模及精度分析

Research on ionospheric modeling and accuracy analysis based on real-time Kalman filtering

文中使用CORS实时数据,基于Kalman滤波建立区域电离层TEC球谐函数模型。使用CORS相位平滑伪距电离层观测值,逐历元滤波求解电离层模型参数,分离卫星与接收机硬件延迟,并应用于单双频PPP定位中。实验结果表明,区域电离层模型精度约为1.9 TECU,较IGS发布的电离层格网数据(GIM)提高58.8%;采用区域电离层模型改正后单频PPP定位精度约为0.2 m,较GIM提高60.3%;模型提供的高精度电离层改正信息能够有效提升双频PPP收敛速度及初始定位精度。

Using the CORS real-time data,the regional ionospheric TEC spherical harmonic model is established by Kalman filtering.The CORS pseudo-range observations smoothing by carrier phase are used to solve the ionospheric model parameters by epoch filter,and the satellite and receiver hardware delays are separated and applied to single-and dual-frequency PPP.The experimental result shows that the accuracy of the regional ionospheric model is about 1.9TECU,which is 58.8%higher than GIM.The accuracy of single-frequency PPP after correction by regional ionospheric model is about 0.2 m,which is 60.3%higher than GIM.The high-precision ionosphere correction provided by the regional model can effectively accelerate the convergence speed and initial positioning accuracy of dual-frequency PPP.