基于GPS的区域电离层层析算法及其应用研究
发布时间：2018-10-17 17:58
【摘要】：电子密度指电离层单位体积内的自由电子数,是电离层的重要物理参量之一,其扰动不仅对无线电波在电离层中的传播产生影响,而且是强烈地壳运动的一种间接反映,因此,研究电离层电子密度扰动对于无线电通讯和地震监测预警均具有重要的现实意义。随着全球导航卫星系统(Global Navigation Satellite System,简称GNSS)及电离层探测技术的迅速发展,基于GNSS的电离层电子密度三维重建技术——电离层层析成像技术成为一种高效可靠的电离层探测手段,由于其具有高精度、低成本和可实时探测等优点,适合于监测电离层电子密度三维空间分布及其扰动。本文从计算机层析成像理论出发,系统阐述了电离层层析成像的基本原理和方法,重点就电离层电子密度反演过程中涉及到的若干关键环节进行了深入研究和代码实现。本文的主要工作如下：(1)深入研究了电离层层析重建过程中GPS原始数据预处理、离散化基函数选取、有效射线判定和系数矩阵建立方法；(2)系统研究了电离层层析成像的重建算法,重点对乘法代数重建算法松弛因子的选取进行了改进；(3)在算法研究基础上,利用IDL语言编写了基于地基GPS观测数据的电离层层析反演软件；(4)运用上述软件,基于日本区域150多个GPS连续运行观测站数据,重构了3·11日本本州岛特大地震前3天(2011年3月8日)及同震(2011年3月11日)当天的电离层电子密度分布,并对结果进行了分析。
[Abstract]:Electron density refers to the number of free electrons in the unit volume of the ionosphere, which is one of the important physical parameters of the ionosphere. Its disturbance not only affects the propagation of radio waves in the ionosphere, but also is an indirect reflection of the strong crustal movement. The study of ionospheric electron density disturbance is of great practical significance for radio communication and earthquake monitoring and warning. With the rapid development of global navigation satellite system (Global Navigation Satellite System,) and ionospheric detection technology, ionospheric tomography (Ionospheric tomography), which is based on GNSS, has become an efficient and reliable method for ionospheric detection. Because of its advantages of high accuracy, low cost and real-time detection, it is suitable for monitoring the three-dimensional spatial distribution of ionospheric electron density and its disturbance. Based on the theory of computer tomography, the basic principles and methods of ionospheric tomography are systematically described in this paper, and some key links involved in the inversion of ionospheric electron density are emphatically studied and realized by code. The main work of this paper is as follows: (1) the preprocessing of GPS original data, the selection of discretization basis function, the effective ray judgment and the method of coefficient matrix establishment in the process of ionospheric tomography reconstruction are studied. (2) the reconstruction algorithm of ionospheric tomography is studied systematically, and the relaxation factor of multiplication algebraic reconstruction algorithm is improved. (3) on the basis of the algorithm research, The ionospheric tomography inversion software based on ground-based GPS observation data is developed by using IDL language. (4) the above software is used based on the data of more than 150 GPS continuous operation stations in Japan. The ionospheric electron density distributions three days before the Honshu earthquake (March 8, 2011) and on the same day of the coseismic earthquake (March 11, 2011) were reconstructed, and the results were analyzed.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228.4;P352
本文编号：2277494
[Abstract]:Electron density refers to the number of free electrons in the unit volume of the ionosphere, which is one of the important physical parameters of the ionosphere. Its disturbance not only affects the propagation of radio waves in the ionosphere, but also is an indirect reflection of the strong crustal movement. The study of ionospheric electron density disturbance is of great practical significance for radio communication and earthquake monitoring and warning. With the rapid development of global navigation satellite system (Global Navigation Satellite System,) and ionospheric detection technology, ionospheric tomography (Ionospheric tomography), which is based on GNSS, has become an efficient and reliable method for ionospheric detection. Because of its advantages of high accuracy, low cost and real-time detection, it is suitable for monitoring the three-dimensional spatial distribution of ionospheric electron density and its disturbance. Based on the theory of computer tomography, the basic principles and methods of ionospheric tomography are systematically described in this paper, and some key links involved in the inversion of ionospheric electron density are emphatically studied and realized by code. The main work of this paper is as follows: (1) the preprocessing of GPS original data, the selection of discretization basis function, the effective ray judgment and the method of coefficient matrix establishment in the process of ionospheric tomography reconstruction are studied. (2) the reconstruction algorithm of ionospheric tomography is studied systematically, and the relaxation factor of multiplication algebraic reconstruction algorithm is improved. (3) on the basis of the algorithm research, The ionospheric tomography inversion software based on ground-based GPS observation data is developed by using IDL language. (4) the above software is used based on the data of more than 150 GPS continuous operation stations in Japan. The ionospheric electron density distributions three days before the Honshu earthquake (March 8, 2011) and on the same day of the coseismic earthquake (March 11, 2011) were reconstructed, and the results were analyzed.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228.4;P352
【参考文献】
相关硕士学位论文 前1条
1 何玉晶;GPS电离层延迟改正及其扰动监测的分析研究[D];解放军信息工程大学;2006年
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