联合GNSS/LEO卫星观测数据的区域电离层建模与精度评估

高精度的电离层模型对于提高导航卫星系统的定位精度具有重要意义.低轨卫星的快速发展为建立高精度的电离层模型提供了新的契机.基于仿真数据模拟获得2017年1月1日-30日LEO (low earth orbit)和GNSS(global navigation satellite system)卫星观测数据,星座类型包括60...

Regional Ionospheric Modeling and Accuracy Assessment Using GNSS/LEO Satellites Observations

High-precision ionospheric model is of great significance for improving the positioning accuracy of navigation satellite system. With the rapid development of low earth orbit satellites, the establishment of a high-precision ionospheric model has provided new opportunities. Based on the simulation data, this paper obtains LEO(low earth orbit) and GNSS(global navigation satellite system) satellites observation data of January 1 to 30, 2017 by means of simulation. The constellation types include 60, 96, 192 and 288 satellites respectively. Based on these data and taking African region as an example, the coverage of GNSS and LEO satellites’ ionospheric pierce points and the joint modeling accuracy are studied. The results show that, after LEO satellites are added, the distribution of ionospheric pierce points is significantly improved,which leads to a noticeable rise of their density. The range of ionospheric pierce points of single low-orbit satellite is larger than that of GNSS satellite, and the altitude angle and azimuth angle of LEO satellite change remarkably. With the increase of the number of low-orbit satellites, the accuracy of joint modeling also rises up. Within different latitudes of 30° E at UTC 12: 00, the difference between GNSS-only and GNSS+288 LEO ionospheric modeling results is the largest, reaching-1.6 TECU. With the increase of modeling time, the difference between the joint modeling results and GNSS-only results gradually decreases.