高轨道目标电离层折射修正方法研究

Study on ionospheric refraction error correction method for high orbit target

为了满足高轨道目标高精度测控的需要,提出了基于双频GNSS的空间投影法和自适应网格法两种电离层距离折射误差修正方法,并对比分析了两种方法在不同仰角、角径时电离层距离折射误差修正精度.分析结果显示:对于2.0 GHz电波信号而言,在较高仰角(仰角>45°)处,空间投影法和自适应网格法修正精度较高,均优于0.2 m;在低仰角和大角径时,空间投影法修正剩余快速增大,修正精度快速降低恶化,达到米量级,而自适应网格法修正精度则不受仰角和角径的影响.这表明:自适应网格法电离层距离修正精度高,适用性强,且便于工程应用,可为提高高轨道目标的测控精度提供有力支撑.

In order to meet the need of high precision measurement and control for deep space and high orbit targets, two ionospheric refraction error correction methods based on dual frequency GNSS are proposed, which are space projection method and adaptive mesh method, and the accuracy of ionospheric range refraction error is compared and analyzed when the elevation angle and angle diameter are different. The analysis results indicate that when the correction residual of spatial projection method and adaptive grid method is smaller, and the correction accuracy is better than 0.2 m for 2.0 GHz radio-wave signal with the elevation > 45°. With the decrease of elevation angle or the increase of angle diameter, the correction residual of space projection method increases rapidly, and the correction accuracy decreases to the order of m, while the correction residual of adaptive grid method is hardly affected by elevation angle and angle diameter. The results show that the adaptive grid method has higher correction accuracy, and has stronger applicability for different elevation angles targets, which is more suitable for ionospheric refraction error in engineering.