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Numerical Study on the Mixed Model in the GOCE Polar Gap Problem

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Geo-Spatial Information Science 2011年第3期14卷 216-222页

作者： zou xiancai CAI Jianqing Nico Sneeuw LI Jiancheng Institute of Geodesy University of Stuttgart Geschwister-Scholl-Str. 24D D-70174 Stuttgart Germany School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China

Gravity gradients acquired by the Gravity field and steady-state Ocean Circulation Explorer(GOCE) do not cover the entire earth because of its sun-synchronous orbit leaving data gaps with a radius of about 6.5° in the polar *** studies showed that the loss of data in the polar regions deteriorates the accuracy of the low order(or near zonal) coefficients of the earth gravity model,which is the so-called polar gap problem in *** order to find a stable solution for the earth gravity model from the GOCE gravity gradients,three models,*** Gauss-Markov model,light constraint model and the mixed model,are compared and evaluated numerically with the gravity gradient simulated with the *** comparison shows that the Best Linear Uniformly Unbiased Estimation(BLUUE) estimator of the mixed model can solve the polar gap problem as effectively as the light constraint model;furthermore,the mixed model is more rigorous in dealing with the supplementary information and leads to a better accuracy in determining the global geoid.

关键词：地球重力模型卫星重力 GOCE 混合模型极的差距问题

Accuracy Analysis of Geopotential Coefficients Recovered from In-situ Disturbing Potential by Energy Conservation Method

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Geo-Spatial Information Science 2007年第4期10卷 255-259页

作者： zou xiancai LI Jiancheng LUO Jia XU Xinyu School of Geodesy and Geomatics 129 Luoyu Road Wuhan 430079 China

在恢复地球严肃模特儿(EGM ) 由创造的标准方程的特征最少平方(LS ) 从在原处扰乱的潜力的调整详细被讨论。标准方程仅仅看情况，这能被结束先验的重力模型的在轨道，和选择没在 LS 答案上有效果。因此，恢复严肃模型的精确性能精确地... 详细信息

在恢复地球严肃模特儿(EGM ) 由创造的标准方程的特征最少平方(LS ) 从在原处扰乱的潜力的调整详细被讨论。标准方程仅仅看情况，这能被结束先验的重力模型的在轨道，和选择没在 LS 答案上有效果。因此，恢复严肃模型的精确性能精确地被模仿。从这个点开始，与噪音的不同水平沿着轨道扰乱潜力的四个集合被模仿并且被用来恢复 EGM。结果证明在加速表刻度的当前的精确性水平上， EGM 的精确性不是足够的反映地球的重力场的时间可变性，作为揭示的动态方法。

关键词：能量法扰动位系数精度分析最小二乘法

Solving Three Types of Satellite Gravity Gradient Boundary Value Problems by Least-Squares

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Geo-Spatial Information Science 2007年第3期10卷 168-172页

作者： XU Xinyu LI Jiancheng zou xiancai CHU Yonghai School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China. 不详

The principle and method for solving three types of satellite gravity gradient boundary value problems by least-squares are discussed in detail. Also, kernel function expressions of the least-squares solution of three geodetic boundary value problems with the observations {Γ zz },{Γ xz , Γ yz} and {Γ xx -Γ yy ,2 Γxy}are presented. From the results of recovering gravity field using simulated gravity gradient tensor data, we can draw a conclusion that satellite gravity gradient integral formulas derived from least-squares are valid and rigorous for recovering the gravity field.

关键词：卫星重力倾斜度最小平方边值问题

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GOCE引力梯度内部校准方法

测绘学报 2022年第2期51卷 192-200页

作者：潘娟霞邹贤才武汉大学测绘学院湖北武汉430079 武汉大学地球空间环境与大地测量教育部重点实验室湖北武汉430079

GOCE卫星引力梯度仪的精确校准是反演高精度重力场的前提之一,本文利用GOCE卫星L1b数据中的引力梯度仪及恒星敏感器数据实现了卫星引力梯度的内部校准。以最小二乘联合多个恒星敏感器观测数据确定内部校准使用的角速度,有效避免了单个... 详细信息

GOCE卫星引力梯度仪的精确校准是反演高精度重力场的前提之一,本文利用GOCE卫星L1b数据中的引力梯度仪及恒星敏感器数据实现了卫星引力梯度的内部校准。以最小二乘联合多个恒星敏感器观测数据确定内部校准使用的角速度,有效避免了单个恒星敏感器低精度角速度分量对坐标转换过程的影响。考虑到恒星敏感器坐标系与梯度仪坐标系间旋转矩阵随时间的变化,本文在ESA官方内部校准方法的基础上,提出了顾及旋转矩阵校准参数的内部校准模型,并利用2009年11月的GOCE实测数据验证了该方法的效果。结果表明,该旋转矩阵校准参数数值约100″,且在该月存在3″~30″的漂移;与GOCE官方内部校准方法对比,从卫星引力梯度精度结果来看,在低于0.005 Hz频段内,同时解算旋转矩阵的校准参数与梯度仪内3个加速度计对的校准参数的内部校准模型优于仅考虑加速度计对校准参数的模型;除此之外,本文讨论了以该模型为基础的GOCE梯度仪数据校准的可能方法,为GOCE及后续重力卫星的数据处理工作提供参考。

关键词： GOCE 引力梯度加速度计内部校准姿态重建

Accuracy Analysis for SST Gravity Field Model in China

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Geo-Spatial Information Science 2006年第4期9卷 265-268页

作者： LUO Jia LUO Zhicai zou xiancai WANG Haihong School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China 不详

Taking China as the region for test, the potential of the new satellite gravity technique, satellite-to-satellite tracking for improving the accuracy of regional gravity field model is studied. With WDM94 as reference, the gravity anomaly residuals of three models, the latest two GRACE global gravity field model (EIGEN_GRACE02S, GGM02S) and EGM96, are computed and compared. The causes for the differences among the residuals of the three models are discussed. The comparison between the residuals shows that in the selected region, EIGEN_GRACE02S or GGM02S is better than EGM96 in lower degree part (less than 110 degree). Additionally, through the analysis of the model gravity anomaly residuals, it is found that some systematic errors with periodical properties exist in the higher degree part of EIGEN and GGM models, the results can also be taken as references in the validation of the SST gravity data.

关键词： SST 重力场中国卫星物理大地测量

Comparison of Present SST Gravity Field Models

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Geo-Spatial Information Science 2006年第3期9卷 175-179页

作者： LUO Jia SHI Chuang zou xiancai WANG Haihong School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China

Taking the main land of Europe as the region to be studied, the potential of the new satellite gravity technique: satellite-to-satellite tracking (SST) and improving the accuracy of regional gravity field model with the SST models are investigated. The drawbacks of these models are discussed. With GPM98C as the reference, the gravity anomaly residuals of several other models, the latest SST global gravity field models (EIGEN series and GGM series), were computed and compared. The results of the comparison show that in the selected region, some systematic errors with periodical properties exist in the EIGEN and GGM’s S series models in the high degree and order. Some information that was not shown in the classic gravity models is detected in the low and middle degree and order of EIGEN and GGM’s S series models. At last, the effective maximum degrees and orders of SST models are suggested.

关键词：卫星跟踪地心力物理大地测量 SST

Simulation of earth gravity field using satellite constellation with variable inclination configuration

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Geodesy and Geodynamics 2021年第5期12卷 323-328页

作者： Qian Zhao Weiping Jiang Xinyu Xu xiancai zou Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China Research Center of GNSS Wuhan University129 Luoyu RoadWuhan 430079China School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079China

Based on a satellite constellation composed of two GRACE-type satellite formations with different inclinations(near polar orbit + low inclination) and the theory of repeat orbit cycle, we discuss the methods for selecting medium-low inclinations for global and local gravity fields. The effects of this constellation configuration on gravity field inversion are comparatively analyzed using a whole-course dynamics simulation. The results show that compared with the single GRACE-type satellite formation,the use of satellite constellations with different inclination configurations improves the gravity solution precision by 34%. The inclusion of multi-directional observations can improve the spatio-temporal resolution of the satellite missions, and yield gravity field solutions with higher isotropic ***, it is necessary to select the optimal low inclination according to the study area, which will have a significant influence on the gravity field solution.

关键词： Satellite constellation Low inclination Multi-directional observations Inversion of gravity field

GOCE卫星重力梯度校准与无阻尼控制效果分析

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测绘学报 2018年第3期47卷 291-297页

作者：邹贤才武汉大学测绘学院湖北武汉430079 地球空间信息技术协同创新中心湖北武汉430079

GOCE卫星是首颗搭载高精度梯度仪,通过加速度计差分测量确定地球重力场的现代重力卫星。该卫星设计为无阻尼飞行状态(沿轨方向),加速度计并未安置在卫星质心,这些特点使得GOCE与标准的卫星跟踪卫星重力测量模式有着显著的区别。本文首... 详细信息

GOCE卫星是首颗搭载高精度梯度仪,通过加速度计差分测量确定地球重力场的现代重力卫星。该卫星设计为无阻尼飞行状态(沿轨方向),加速度计并未安置在卫星质心,这些特点使得GOCE与标准的卫星跟踪卫星重力测量模式有着显著的区别。本文首先指出GOCE任务中普通模式加速度校准存在不严密性问题,并提出了分别校准6个加速度计,分离偏差参数的方案。利用GOCE任务期内的几何法精密轨道,采用动力法完成校准,并分析了无阻尼控制的效果,发现:(1)虽然GOCE所在轨道高度的中性大气密度较GRACE高两到三个量级,但GOCE卫星在沿轨方向的残余非保守力比GRACE卫星的对应分量小一个量级,充分显示了无阻尼控制系统的补偿效果;(2)通过精密轨道内插的轨道速度与动力法轨道速度的比较可以得出,卫星无阻尼控制系统对GOCE卫星速度的显著影响;(3)计算了GOCE卫星所受的非保守力。获得了GOCE任务期间的加速度计校准参数,并讨论了利用其辅助重力梯度仪数据预处理的可能方法。

关键词：卫星重力引力梯度 GOCE 非保守力动力法

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JPL行星历表的发展及比较

大地测量与地球动力学 2022年第9期42卷 925-930页

作者：刘婉逸邹贤才衷路萍武汉大学测绘学院武汉市430079

基于DE405、DE421、DE430、DE440星历,计算各大行星在地球质心及太阳系质心惯性系中的位置,比较其他星历相对于DE440星历的行星位置精度。分析讨论各历表下月球的地心位置和速度精度,以及历表对于月球探测器的位置和速度从月心惯性系转... 详细信息

基于DE405、DE421、DE430、DE440星历,计算各大行星在地球质心及太阳系质心惯性系中的位置,比较其他星历相对于DE440星历的行星位置精度。分析讨论各历表下月球的地心位置和速度精度,以及历表对于月球探测器的位置和速度从月心惯性系转为月固系的影响,并给出使用建议。结果表明,各大行星由于受观测数据等因素影响,位置精度差异较大,跨度从m级到106 m量级。对于行星的位置精度,DE421和DE430相对于DE405有1~2个量级的提高,DE430相对于DE421提高50%。DE405历表的月球地心位置、速度精度分别为7 m和0.02 mm/s,DE421历表分别为1.5 m和0.004 mm/s,DE430历表分别为1.3 m和0.0035 mm/s。对于星历用于月球探测器从月惯系转为月固系产生的坐标和速度误差,DE405分别为30 m和3 cm/s,DE421分别为1.3 m和1.2 mm/s,DE430分别为1 m和0.9 mm/s。历表对于月球坐标系转换的影响为m级。对于月球探测器导航及相关任务,推荐使用DE430或DE440行星历表。

关键词：行星历表月球探测月固系深空探测精度