基于GPS的區(qū)域電離層層析算法及其應用研究
發(fā)布時間：2018-10-17 17:58
【摘要】：電子密度指電離層單位體積內(nèi)的自由電子數(shù),是電離層的重要物理參量之一,其擾動不僅對無線電波在電離層中的傳播產(chǎn)生影響,而且是強烈地殼運動的一種間接反映,因此,研究電離層電子密度擾動對于無線電通訊和地震監(jiān)測預警均具有重要的現(xiàn)實意義。隨著全球導航衛(wèi)星系統(tǒng)(Global Navigation Satellite System,簡稱GNSS)及電離層探測技術的迅速發(fā)展,基于GNSS的電離層電子密度三維重建技術——電離層層析成像技術成為一種高效可靠的電離層探測手段,由于其具有高精度、低成本和可實時探測等優(yōu)點,適合于監(jiān)測電離層電子密度三維空間分布及其擾動。本文從計算機層析成像理論出發(fā),系統(tǒng)闡述了電離層層析成像的基本原理和方法,重點就電離層電子密度反演過程中涉及到的若干關鍵環(huán)節(jié)進行了深入研究和代碼實現(xiàn)。本文的主要工作如下：(1)深入研究了電離層層析重建過程中GPS原始數(shù)據(jù)預處理、離散化基函數(shù)選取、有效射線判定和系數(shù)矩陣建立方法；(2)系統(tǒng)研究了電離層層析成像的重建算法,重點對乘法代數(shù)重建算法松弛因子的選取進行了改進；(3)在算法研究基礎上,利用IDL語言編寫了基于地基GPS觀測數(shù)據(jù)的電離層層析反演軟件；(4)運用上述軟件,基于日本區(qū)域150多個GPS連續(xù)運行觀測站數(shù)據(jù),重構了3·11日本本州島特大地震前3天(2011年3月8日)及同震(2011年3月11日)當天的電離層電子密度分布,并對結果進行了分析。
[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.
【學位授予單位】：東北大學
【學位級別】：碩士
【學位授予年份】：2013
【分類號】：P228.4;P352
本文編號：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.
【學位授予單位】：東北大學
【學位級別】：碩士
【學位授予年份】：2013
【分類號】：P228.4;P352
【參考文獻】
相關碩士學位論文 前1條
1 何玉晶;GPS電離層延遲改正及其擾動監(jiān)測的分析研究[D];解放軍信息工程大學;2006年
，本文編號：2277494
本文鏈接：http://www.lk138.cn/kejilunwen/dizhicehuilunwen/2277494.html
最近更新
教材專著
