基于地基GNSS和COSMIC掩星数据吸收的三维电离层电子密度重构方法

精确给出电离层的实时变化信息对现代通信和卫星导航等系统可靠应用具有非常重要的意义.为提高电离层经验模型电子密度的输出精度,提出了一种基于地基GNSS和COSMIC掩星数据吸收的三维电离层电子密度重构的新方法.以最新版国际参考电离层模型IRI-2016为背景模型,选择IG指数与Rz指数作为驱动量,采用Brent算法分两步实现了地基GNSS和COSMIC掩星数据的吸收.与欧洲区域8个垂测站实测数据的对比表明:数据吸收后模型重构的电离层NmF2的绝对平均误差和标准差分别下降了33%和29%;电离层hmF2的重构误差则分别下降了约55%和30%.对比结果验证了所提方法的精度和有效性.

Three-dimensional ionospheric electron density reconstruction by data ingestion of ground-based GNSS and COSMIC occultation measurements

Accurate determination of the ionospheric real-time state plays an important role in radiowave information systems such as modern communication and satellite navigation system. To provide three-dimensional(3D) specification of the ionosphere electron density for current conditions, a new 3D ionospheric electron density reconstruction method is developed by data ingestion of ground-based global navigation satellite system(GNSS) and constellation observing system for meteorology, ionosphere and climate(COSMIC) occultation measurements. Based on the latest International Reference Ionosphere model (IRI-2016), IG index and Rz index of IRI-2016 are selected as the driving parameter. With Brent algorithm, optimal IG and RZ indices are obtained in two steps by data ingestion of ground GNSS and COSMIC occultation measurements. The comparison between reconstructed results and data of eight ionosonode stations in the European region indicates that the absolute mean error and standard deviation of the reconstructed ionospheric N_mF₂ were decreased by 33% and 29% respectively, while the reconstruction error of the ionospheric h_mF₂ decreased by about 55% and 30% respectively. Comparison results demonstrate the accuracy and effectiveness of the proposed method.