利用CHAMP卫星星历及加速度计数据推求地球重力场模型

讨论基于CHAMP卫星星历和加速度计数据推求地球重力场模型的数值微分算法.首先利用牛顿内插公式,根据CHAMP卫星星历观测值求解卫星运动加速度.在计算卫星加速度时,建议采用速度数据内插加速度.扣除其他非地球引力摄动加速度后,基于牛顿运动定律建立观测方程.利用GFZ数据中心提供的24天CHAMP星历数据和加速度计数据解算出50×50阶地球重力场模型,并与EGM96模型进行比较,结果表明两者在低阶位系数上有较好的一致性.     

利用CHAMP科学轨道数据和星载加速度计数据反演地球重力场

基于卫星动力学理论,采用德国地球科学中心GFZ提供的CHAMP精密轨道数据和星载加速度计数据,反演了36阶地球重力场模型CDS01S。用不同模型之间的位系数差比较模型CDS01S、EIGEN3P、EIGEN1S及EGM96,表明CDS01S模型的位系数最接近于EIGEN3P;比较上述几种模型的位系数精度,表明CDS01S模型的位系数精度高于EGM96;用CDS01S和GGM01C的前30阶位系数分别计算全球2°×2°网格的大地水准面起伏,两者之间的标准偏差为4.7 cm。     

地球重力场模型对低轨卫星轨道积分的影响

介绍3种不同的地球重力场模型及其(约化)动力学定轨中所涉及的动力学模型,并基于Collocation轨道积分方法对CHAMP卫星进行数值积分,然后将轨道积分结果与JPL快速精密星历相比较。实验结果表明,由CHAMP卫星SST数据反演生成的EIGEN-2模型引力位系数具有较高的精度,能够满足低轨卫星精密定轨的需要。     

利用现有重力场模型求定CHAMP卫星加速度计修正参数

CHAMP卫星加速度计数据的标定是通过确定其尺度因子和偏差参数来完成的.本文基于能量守恒方程,给出利用现有重力场模型标定CHAMP卫星加速度数据的基本原理和数学模型;提出相邻历元间差分算法,大大简化了观测方程,同时避免积分常量的计算.该算法既能同时解算尺度因子和偏差参数,也可任意求解其中之一.基于实测的CHAMP卫星加速度数据,利用EGM96模型和最新公布的EIGEN-2模型进行计算与比较,验证该方法的有效性.     

重力场模型对Swarm卫星简化动力学定轨的影响

利用简化动力学定轨的方法,联合Swarm星载GPS观测数据和简化的动力学模型,在确定性运动方程中引入优选的伪随机脉冲参数,实现了Swarm卫星的精密定轨;并详细分析了JGM3、EGM96、EGM2008以及EIGEN-6C4地球重力场模型对Swarm卫星简化动力学定轨精度的影响。实验结果表明,高于40阶次的JGM3、EGM96、EGM2008以及EIGEN-6C4重力场模型均可使Swarm卫星单天解定轨精度优于8 cm,EGM2008与EIGEN-6C4解算的定轨精度优于JGM3和EGM96。     

基于方差分量估计的CHAMP重力场恢复方法

基于德国慕尼黑技术大学(TUM)提供的100 d的CHAMP卫星几何法轨道和GFZ提供的加速度计数据,计算出了50×50阶地球重力场模型XISM-CHAMP01,并与EIGEN-CG03C、EIGEN-CHAMP03S、EIGEN2、EIGEN1S、EGM96模型进行了比较。结果表明,XISM-CHAMP01模型精度明显优于相同阶次EGM96模型和EIGEN1S模型,并与EIGEN2模型精度相当。     

CHAMP卫星能量守恒方程及其误差分析

利用CHAMP卫星轨道和加速度计数据恢复地球重力场模型的一种有效方法是能量守恒方法。本文详细给出了能量守恒方法的基本原理和数学模型，推导了惯性系和地固系下的能量守恒方程，并将其表示成三维直角分量的形式。论文最后分析了能量方程中各项误差影响。     

高阶地球重力场模型的评价及其优选

采用"移去-恢复"技术确定大地水准面,需要一个全球重力场模型作为参考场。本文采用基于模糊集合理论的最大隶属度原则,通过某试验区的33个GPS水准点的实测大地水准面差距与模型大地水准面差距的比较分析,从国际重力场服务提供的EGM96、EIGEN-CG01C、EIGEN-CG03C、GFZ93A、GFZ96、OSU91A、PGM2000A等七个高阶全球重力场模型中,选择OSU91A作为该地区最优的参考重力场模型。     

利用CHAMP卫星星历恢复引力位模型的模拟研究

对CHAMP卫星星历恢复引力位模型的精度，使用3种方法和不同积分弧长作了模拟计算，结果表明，采用正则化方法并扩展积分弧长将有助于提高解算法系数的精度，预期CHAMP卫星观测将使现有引力位模型低阶位系数的精度提高1－2个数量级。     

大地测量学

CH20041546利用CHAMP卫星星历及加速度计数据推求地球重力场模型=Recoverying the Gravitational Poten- tial Model from the Ephemerides and Accelermeter of CHAMP/徐天河,杨元喜(西安测绘研究所)∥测绘学报．-2004,33(2)．-95-99 讨论基于CHAMP卫星星历和加速度计数据推求地球重力场模型的数值微分算法。首先利用牛顿内插公式, 根据CHAMP卫星星历观测值求解卫星运动加速度。在计算卫星加速度时,建议采用速度数据内插加速度。扣除其他非地球引力摄动加速度后,基于牛顿运动定律建立观     

改进的能量守恒方法及其在CHAMP重力场恢复中的应用(英文)

An efficient method for gravity field determination from CHAMP orbits and accelerometer data is referred to as the energy balance approach. A new CHAMP gravity field recovery strategy based on the improved energy balance approach IS developed in this paper. The method simultaneously solves the spherical harmonic coefficients, daily Integration constant, scale and bias parameters. Two 60 degree and order gravitational potential models, XISM-CHAMPO1S from the classical energy balance approach, and XISM-CHAMPO2S from the improved energy balance, are determined using about one year＇s worth of CHAMP kinematic orbits from TUM and accelerometer data from GFZ. Comparisons among XISM-CHAMPO1S, XISM-CHAMPO2S, EIGEN-CGO3C, EIGEN-CHAMPO3S, EIGEN2, ENIGNIS and EGM96 are made. The results show that the XISM-CHAMPO2S model is more accurate than EGM96, EIGENIS, EIGEN2 and XISM-CHAMPO1S at the same degree and order, and has almost the same accuracy as EIGEN-CHAMPO3S.     

基于能量守恒方法恢复CHAMP重力场模型

介绍了基于能量守恒定律恢复地球重力场模型的基本原理和算法.指出了CHAMP加速度计数据存在的问题,提出了整体求解尺度因子、偏差参数和偏差漂移的数学模型及差分算法.利用2002年1月的CHAMP快速科学轨道数据和加速度计数据计算出了50 × 50地球重力场模型XISM02.将该模型与EGM96,GRIM5C1,EIGEN1S,EIGEN2模型进行了比较,并用北极实测重力数据对上述模型进行了检验.结果表明:XISM02模型在北极地区精度与EIGEN1S,EIGEN2相当.     

Earth gravity field recovered from CHAMP science orbit and accelerometer data

The earth gravity field model CDS01S of degree and order 36 has been recovered from the post processed Science Orbits and on-board accelerometer data of GFZ's CHAMP satellite. The model resolves the geoid with an accuracy of better than 4 cm at a resolution of 700 km half-wavelength. By using the degree difference variances of geopotential coefficients to compare the model CDS01S with EIGEN3P, EIGEN1S and EGM96, the result indicates that the coefficients of CDS01S are most close to those of EIGEN3P. The result of the comparison between the accuracies of geopotential coefficients in the above models, indicates that the accuracy of coefficients in CDS01S is higher than that in EGM96. The geoid undulations of CDS01S and GGM01C up to 30 degrees are calculated and the standard deviation is 4. 7 cm between them.     

Earth gravity field recovered from CHAMP science orbit and accelerometer data

IntroductionSince the launch of man-made satellite early in1957 ,the research for satellite gravity has beentaken a wide attentioninfield of geodesy .Early ,the ground-based satellite tracking has providedan observational data set which has been used tode…     

Calibration for CHAMP Accelerometer Data Based on Crossover Points of the Satellite

The German CHAlleging Minisatellite Payload （CHAMP） was launched in July 2000. It is the first satellite that provides us with position and accelerometer measurements, with which the gravity field model can be determined. One of the most popular methods for geopotential recovery using the position and accelerometer measurements of CHAMP is the energy conservation method, The main aim of this paper is to determine the scale and bias parameters of CHAMP accelerometer data using the energy conservation method. The basic principle and mathematical model using the crossover points of CHAMP orbit to calibrate the accelerometer data are given based on the energy balance method. The rigorous integral formula as well as its discrete form of the observational equation is presented, This method can be used to estimate only one of the scale and bias parameters or both of them. In order to control the influence of outliers, the robust estimator for the calibration parameters is given. The results of the numerical computations and comparisons using the CHAMP accelerometer data show the validity of the method.     

利用卫星轨迹交叉点标定CHAMP卫星加速度计数据

基于能量守恒方程给出了利用卫星轨迹交叉点标定CHAMP卫星加速度数据的基本原理和方法 ,并给出了其严密的积分公式及其离散化形式。为了控制加速度数据的扰动异常 ,建议采用抗差估计求解参数值 ,并基于实测的CHAMP卫星加速度计数据进行了计算与比较 ,验证了该方法的有效性     

‘DEOS_CHAMP-01C_70’: a model of the Earth’s gravity field computed from accelerations of the CHAMP satellite

Performance of a recently proposed technique for gravity field modeling has been assessed with data from the CHAMP satellite. The modeling technique is a variant of the acceleration approach. It makes use of the satellite accelerations that are derived from the kinematic orbit with the 3-point numerical differentiation scheme. A 322-day data set with 30-s sampling has been used. Based on this, a new gravity field model – DEOS_CHAMP-01C_70 - is derived. The model is complete up to degree and order 70. The geoid height difference between the DEOS_CHAMP-01C_70 and EIGEN-GRACE01S models is 14 cm. This is less than for two other recently published models EIGEN-CHAMP03Sp and ITG-CHAMP01E. Furthermore, we analyze the sensitivity of the model to some empirically determined parameters (regularization parameter and the parameter that controls the frequency-dependent data weighting). We also show that inaccuracies related to non-gravitational accelerations, which are measured by the on-board accelerometer, have a minor influence on the computed gravity field model.