摘要
推导了由扰动重力梯度张量单分量Tzz和组合分量Txx+Tyy、Tzz-Txx-Tyy反演地球重力场的调和分析法模型,测试了不同格网分辨率和含有不同噪声的扰动重力梯度数据对重力场模型解算结果精度的影响,验证了扰动重力梯度张量单分量和组合分量调和分析法模型恢复地球重力场的有效性。实验结果表明,由于在模型解算时梯度数据的延拓和格网化误差以及平滑因子无法准确选定等问题的影响,使得调和分析法并不能100%地确定地球重力场;随着梯度数据中所含误差的不断增大,其确定的重力场模型有效阶次和精度呈不断下降的趋势;在确定重力场模型时,Tzz-Txx-Tyy的精度最高,其次为Tzz,Txx+Tyy最差。
The harmonic analysis model of single component Tzz and composite components Txx＋Tyy,Tzz-Txx-Tyy of disturbed gravity gradient tensor to compute the Earth＇s gravitational field model（EGM） are deduced.The influences of disturbed gravity gradient data in different resolutions and with different errors on the accuracy of EGM are analyzed.Thus,the models established here are validated with simulated data.Results show that the harmonic analysis method could not recover the EGM completely because of the influence of continuation and gridding errors as well as the indetermination of smoothness factor.The effective degree and accuracy of EGM are gradually falling along with the increase of errors.The accuracy of EGM computed by composite components Tzz-Txx-Tyy is the highest while that of the composite components Txx＋Tyy is the lowest.
出处
《大地测量与地球动力学》
CSCD
北大核心
2012年第5期103-107,112,共6页
Journal of Geodesy and Geodynamics
基金
国家自然科学基金(41174026
41104047
41174017)
关键词
地球重力场模型
调和分析法
卫星重力梯度
球谐函数
GOCE
Earth＇s Gravitational field Model（EGM）
harmonic analysis method
Satellite Gravity Gradient（SGG）
spherical harmonic function
GOCE
