基于不同电离层模型的精密单点定位精度分析

Accuracy Analysis of Precise Point Positioning Based on Different Ionospheric Models

随着PPP的发展与应用,对PPP误差源的研究更加精细、更加科学。电离层折射是高精度PPP的主要误差之一,国内外通用方法是用大气传播理论建立电离层修正模型。本文主要探讨了电离层对精密单点定位影响的基本理论,总结了目前常用方法;研究了Klobuchar模型的改正公式及计算方法;系统地研究了双频观测值建立消电离层延迟模型的理论和方法。使用相同时段的观测数据,将广播星历、Klobuchar模型和双频观测值改正消电离层模型的结果进行比较,发现用GPS双频观测值建立的消电离层模型的精度明显优于广播星历及Klobuchar模型。

With the development and application of PPP,the study of PPP error source is more accurate and scientific.Ionospheric refraction is one of the main errors of high precision PPP.The common domestic and international method is to establish the ionospheric correction model by atmospheric propagation theory.In this paper,the basic theory of the effect of ionosphere on precise point positioning is discussed,and the commonly used methods are summarized.The correction formula and calculation method of Klobuchar model are studied.It is systematically studied that the theory and method of the correcting model of ionosphere in use of the double frequency data based on the observation data of the same period,the results of the broadcast ephemeris,the Klobuchar model,and the corrected oblique ionospheric model by double frequency observation were compared.It was found that the accuracy of the ionospheric model established by the GPS dual frequency observation was superior to that of the broadcast ephemeris and Klobuchar model.