基于北斗地基增强系统的中国区域电离层建模研究

Study on China regional ionosphere modeling based on BeiDou ground-based augmentation system

在卫星导航定位中,电离层延迟误差是主要误差源之一,其影响可以到达数米乃至数百米,有必要进行高精度的电离层模型研究,尤其是区域的高精度电离层模型建立.本文基于北斗地基增强系统114基准站三系统(GPS/BDS/GLONASS)双频的观测数据进行电离层提取计算,并结合多项式函数模型进行建模,得出中国区域内的电离层模型,并采用直接跟CODG的电离层产品比较和间接通过单频精密单点定位方式来评估模型精度.结果表明,基于北斗地基增强系统建立的中国区域电离层模型精度高于CODG发布的电离层格网模型且更符合中国区域电离层的真实空间分布.

For GNSS navigation and positioning,ionospheric delay is one of the main error sources,and its influence can reach to several meters or even hundreds of meters.Therefore,it is necessary to study high-precision ionospheric model,especially regional ionospheric model establishment.In this study,a regional ionospheric model based on BeiDou foundation strengthening system is studied.By calculating the observation data of the three systems(GPS/BDS/GLONASS)of BeiDou foundation strengthening system and combining with the polynomial function model for modeling,the ionosphere model in China is obtained.The model precision was evaluated by direct comparison with CODG and indirect single frequency precision single point positioning results.The validations show that the accuracy of the regional ionospheric model based on the BeiDou foundation strengthening system is higher than of the ionospheric grid model published by CODG,and more consistent with the actual ionospheric spatial distribution.