超高阶地球重力场模型的构建

发布时间：2018-01-23 19:15

本文关键词： 超高阶地球重力场模型轮胎调和椭球谐分析块对角最小二乘格网化 FFT 谱权组合椭球改正 Legendre　出处：《解放军信息工程大学》2013年硕士论文　论文类型：学位论文

【摘要】：随着卫星重力的快速发展，其确定的中低阶模型的精度不断提高，再加上全球高分辨率数据的逐步完善，使得所能构建的地球重力场模型阶数不断增加，目前国际上已有的最通用精度最好的EGM2008模型达到2190阶2159次的水平，我国急需构建属于自己的高精度全球超高阶地球重力场模型，本文主要研究了重力场模型的构建方法，并利用我国独立生成的全球重力格网数据解算出一精度与EGM2008相当的超高阶地球重力场模型，作者在文中所做的主要工作和创新点有： 1总结推导了地球重力场模型构建的基本理论和公式，简要介绍了获得全球格网平均重力异常数据的生成过程； 2通过计算比较，分析了Legendre函数递推的精度及其效率问题，并针对高纬度地区Legendre溢出的问题作了分析计算，得到了比较好的解决，对于Legendre函数积分值的递推，比较了向前和向后递推方法，得出使用向前递推完全能够满足精度要求的结论； 3推导了FFT方法在使用数值积分方法构建地球重力场模型以及在模型重力异常计算中的应用，通过与传统方法比对计算时间和计算结果，FFT方法在不损失精度的情况下，，计算效率明显提高； 4总结了重力场模型位系数的求解方法，对各种方法的优劣性进行了分析，尤其详细总结了块对角最小二乘方法在EGM96和EGM2008构建中的应用，指出了使用最小二乘方法构建重力场模型这一趋势，为我国今后构建自己高精度的超高阶地球重力场模型起到一定得借鉴作用； 5采用谱权组合的方法，对地面数据构建的模型位系数和卫星模型位系数进行了联合，解决了使用卫星模型系数直接替代地面数据计算的模型低阶部分而出现的阶方差和误差阶RMS曲线不光滑的现象，实现了两种模型位系数的融合； 6本文使用自主构建的全球5'×5'格网平均重力异常，经过格网数据坐标系的转换椭球谐分析下的轮胎调和椭球谐系数与球谐系数的转换椭球改正以及谱权组合或直接替代两种方式联合Eigen06S卫星重力场模型，构建了一个相对独立的超高阶地球重力场模型CSnm_1和CSnm_2，采用我国区域均匀分布的1007个独立的GPS/水准点和889个独立的天文大地垂线偏差对以上模型进行了外部检核，结果显示，CSnm_1CSnm_2大地水准面检验精度与EGM2008相当，在剔除20个粗差点后，大地水准面精度能够达到30cm，垂线偏差的检验精度相比EGM2008提高了0.5，在剔除粗差17个点后，精度达到了2.2
[Abstract]:With the rapid development of satellite gravity, the precision of the medium and low order model determined by satellite gravity has been improved continuously, and the global high resolution data have been gradually improved, which makes the order of the Earth gravity field model increasing. At present, the most common and best EGM2008 model in the world has reached the level of 2190th order 2159 times. It is urgent for China to construct its own high-precision global ultra-high order gravity field model. In this paper, the method of constructing gravity field model is studied, and an ultra-high order gravity field model with the same precision as EGM2008 is calculated by using the global gravity grid data generated independently in China. The author's main work and innovations in this paper are as follows: The main contents are as follows: 1. The basic theory and formula for the construction of the gravity field model of the earth are summarized and the generation process of the global grid average gravity anomaly data is introduced briefly. 2 through calculation and comparison, the accuracy and efficiency of recurrence of Legendre function are analyzed, and the problem of Legendre spillover in high latitude is analyzed and calculated. The method of forward and backward recursion is compared for the integral value of Legendre function, and the conclusion that the forward recursive method can completely meet the precision requirement is obtained. (3) the application of FFT method in the construction of gravity field model using numerical integration method and in the calculation of gravity anomaly of the model is derived. The calculation time and results are compared with the traditional method. The calculation efficiency of FFT method is improved obviously without losing precision. 4. The calculation method of potential coefficient of gravity field model is summarized, and the advantages and disadvantages of each method are analyzed. In particular, the application of block diagonal least square method in EGM96 and EGM2008 construction is summarized in detail, and the trend of using least square method to construct gravity field model is pointed out. It can be used for reference for our country to construct our own high-precision model of ultra-high earth gravity field in the future. (5) the model bit coefficients and satellite model bit coefficients constructed by ground data are combined by spectral weight combination method. In this paper, the phenomenon that the order variance and error order RMS curve are not smooth due to the use of satellite model coefficients to replace the low-order part of the ground data directly is solved, and the fusion of the two models bit coefficients is realized. (6) in this paper, the global 5'脳 5 'grid average gravity anomaly is used. Transformation ellipsoid correction of tire harmonic ellipsoid coefficient and spherical harmonic coefficient under the transformation ellipsoid harmonic analysis of grid data coordinate system and combination of spectral weights or direct substitution for Eigen06S satellite gravity field. Model. A relatively independent model of ultra-high gravity field, CSnm_1 and CSnm_2, is constructed. Using 1007 independent GPS / leveling points and 889 independent geodetic perpendicular deviations distributed uniformly in China, the above models are checked. The results show that. The accuracy of CSnm_1CSnm_2 geoid inspection is similar to that of EGM2008. After eliminating 20 rough handicaps, the geoid accuracy can reach 30 cm. The accuracy of perpendicular deviation is 0.5 higher than that of EGM2008. After eliminating gross error of 17 points, the accuracy reaches 2.2.
【学位授予单位】：解放军信息工程大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P223.0

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