基于球谐函数模型的GPS电离层延迟改正分析

Analysis of GPS ionospheric delay and correction based on the model of spherical harmonic functions

电离层延迟误差是影响GPS导航和定位的最主要因素,但由于电离层本身的不稳定性,以及目前对其物理特性还不甚了解,我们只能采用精度有限的经验模型和数学模型对其进行描述。本文介绍了利用球谐函数模型模拟电离层延迟的原理与方法,采用双频伪距精确获得电离层延迟,模拟了中国地区上空的电离层延迟,并对模拟结果进行了分析比较,得出了几点有益结论。

The major factor of impacting GPS navigation and positioning is ionosphere delay error. Because of the instability and the ignorance about physics characteristic of ionosphere, it could only be described by imprecise empirical and mathematic models. The paper first introduced the principle and method of simulating ionosphere delay by spherical harmonic functions model, second practically simulated ionosphere delay above China area, then analyzed the results of simulation, and finally got some helpful conclusions.