基于双频数据组合的可见星电离层延迟研究

Study on Ionospheric Delay in Visible Satellites Based on Dual-frequency Data Combination

电离层延迟是引起卫星定位误差的主要因素之一,为了有效消除该误差的影响,提出一种基于可见卫星双频数据几何无关组合解算电离层延迟的方法。用卫星双频伪码和载波观测量的差分组合对可见卫星进行电离层延迟建模,然后将组合变换为原始观测量的线性形式进行差分解算,最后演化成对观测量的几何无关组合修正电离层延迟。仿真实验得到某一时间段可见卫星的坐标轨迹、电离层延迟以及模型误差。将各种模型的延迟和误差进行比较,结果发现该方法可不同程度有效修正电离层延迟。

The ionospheric delay is one of the main factors forsatellite positioning error.In order to effectively eliminate the effect of this error,this paper proposes a method for calculating ionospheric delay based on dual-frequency independent geometric data combination of visible satellites.Use the difference combination of satellite dual-frequency pseudo-code and observed quantity of carrier for ionospheric modeling of visible satellites;then convert the combination into a linear form of the original observed quantity for differential calculation.Finally,it is evolved into a geometric combination to fix ionospheric delay.The results show coordinate tracks,ionospheric delay and model error of visible satellites in the certain period of time.Comparison of delays and errors of various models verified that this method can effectively amend ionospheric delays in different extents.