利用GPS双频观测值研究电离层

发布时间：2018-03-19 10:40

本文选题：GPS　切入点：电离层　出处：《中国地质大学（北京）》2013年硕士论文　论文类型：学位论文

【摘要】：电离层不仅是GPS定位中的重要误差来源，而且是空间大气成分的重要研究部分，所以对电离层的研究是现在科研的一个非常重要的领域。电磁波信号在电离层中受到的折射影响也成为很多科研工作者重要的研究课题。本篇论文重点研究了电离层的计算原理，计算方法以及不同计算模型的比较分析并探究了为了使穿刺点能够覆盖全球增加穿刺点的方法研究，本论文主要的研究内容如下： 1.介绍了GPS的坐标系统；以及电离层计算用到的时间转换关系；GPS伪距观测值的平滑处理方法；GPS卫星高度角；方位角的计算以及通过广播星历和精密星历来卫星坐标的计算方法。 2.分析了电离层的结构；以及由GPS卫星观测值计算电离层VTEC值的原理；电离层计算过程中的不同的坐标系统；不同的投影函数模型；地心角，，穿刺点经纬度的计算以及地理经纬度和地心经纬度的换算。 3.论述了电离层VTEC值的计算模型：多项式函数模型；三角级数函数模型；球谐函数模型以及三种模型计算的卫星硬件延迟比较。卫星和接收机的联合硬件偏差比较，采用单站计算和采用多站计算的精度比较。 4.对格网内插模型内插出来的VTEC值和由GPS观测值计算的VTEC值在天空正常情况下和异常情况下精度的比较，探究格网模型的适用性。 5．由于IGS跟踪站在北半球分布比南半球分布多，赤道地区和高纬度地区测站少，这就导致了穿刺点的分布状况北半球密，赤道和高纬度地区少。大片海洋上空没有穿刺点严重影响了拟合的精度，论文讨论了增加穿刺点的方法以及用该方法计算的VTEC值的精度分析。
[Abstract]:The ionosphere is not only an important source of errors in GPS positioning, but also an important part of the study of the composition of the space atmosphere. Therefore, the study of ionosphere is a very important field in current scientific research. The influence of the refraction of electromagnetic wave signal in the ionosphere has also become an important research topic for many researchers. The calculation principle of the separation layer, The main contents of this thesis are as follows: (1) in order to make the puncture points cover the whole world, the main contents of this paper are as follows:. 1. The coordinate system of GPS and the smoothing processing method of GPS pseudo-range observations used in ionospheric calculation are introduced. The calculation of azimuth angle and the calculation method of satellite coordinates through broadcast ephemeris and precision stars are presented. 2. The structure of the ionosphere, the principle of calculating the ionospheric VTEC value from the GPS satellite observations, the different coordinate systems in the ionospheric calculation process, the different projection function models, the geocentric angle, The calculation of the longitude and latitude of the puncture point and the conversion of the geographical longitude and latitude to the geocentric longitude and latitude. 3. The calculation models of ionospheric VTEC are discussed: polynomial function model, trigonometric series function model, spherical harmonic function model and satellite hardware delay comparison calculated by three models. The accuracy of single-station calculation is compared with that of multi-station calculation. 4. The applicability of the grid model is explored by comparing the VTEC values interpolated by the grid interpolation model with the VTEC values calculated by the GPS observations under the normal and abnormal conditions of the sky. 5. The distribution of IGS tracking stations in the Northern Hemisphere is more than that in the Southern Hemisphere, and there are fewer stations in the equatorial and high latitudes, which leads to the dense distribution of the puncture points in the Northern Hemisphere. There are few equatorial and high latitudes. The accuracy of fitting is seriously affected by the absence of puncture points over large oceans. The method of increasing puncture points and the accuracy analysis of VTEC values calculated by this method are discussed in this paper.
【学位授予单位】：中国地质大学（北京）
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P352;P228.4

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