摘要
应用张量不变理论对利用卫星重力梯度数据确定地球重力场的方法进行了研究,对张量不变观测方程的线性化处理、非全张量观测值的数据处理策略以及采用白噪声特性下的梯度观测值恢复地球重力场的精度等进行了数值分析。结果表明,张量不变解实现了不同观测值的联合求解,基于先验重力场模型的线性化方法在实现张量不变观测模型线性化处理的同时,提升了张量不变方法的模型解算精度,且初始参考模型的选择对解的收敛特性影响较小;在无噪声和白噪声条件下,利用先验位模型的球谐综合值代替低精度梯度分量实现非全张量梯度观测值的处理均是可行的,不会改变解的收敛速度和最终精度。
Objectives:The objective is to study the tensor invariant method for determining the Earth’s gravity field with satellite gravitational gradient data.Methods:The tensor invariant method does not depend on the acquisition of the spatial orientation information of the gradiometer,so it has a special advantage over the traditional methods in determining the earth gravity field.Numerical analyses are made for the linearization of tensor invariant observation equation,the processing of non-full tensor observation data,and the accuracy of gravity field recovery with the gradient data containing white noise.Results:The results show that the tensor invariant solution realizes the combine processing of the different tensor components.The tailored linearization effectively achieves the linearization of the tensor invariant observation model while the accuracy of gravity field model determined using tensor invariants is significantly higher than that of the single tensor component solution.Also,the choice of initial reference model exerts minor influence on the total iterative process.Conclusions:Due to the non-full tensor gradient observations,it is proposed to replace the low precision gradient component using the spherical harmonic synthesis of a priori gravity field model,which will not change the convergence and the accuracy of the solution even if the white noise exists in the observations because of the nadir-pointing characteristics of the gradiometer.
作者
朱广彬
常晓涛
瞿庆亮
周苗
ZHU Guangbin;CHANG Xiaotao;QU Qingliang;ZHOU Miao(Land Satellite Remote Sensing Application Center,Ministry of Natural Resources,Beijing 100048,China;Key Laboratory of Surveying and Mapping Science and Geospatial Information Technology,Ministry of Natural Resources,Beijing 100830,China;College of Geomatics,Shandong University of Science and Technology,Qingdao 266590,China)
出处
《武汉大学学报（信息科学版）》
EI
CAS
CSCD
北大核心
2022年第3期334-340,共7页
Geomatics and Information Science of Wuhan University
基金
国家自然科学基金(42174041)
高分对地观测重大专项(42-Y20A09-9001-17/18)
民用航天预先研究项目(D010103)
自然资源部地球观测与时空信息科学重点实验室经费(201907)。
关键词
张量不变
卫星引力梯度
线性化
重力场模型
tensor invariant
satellite gravitational gradient
linearization
gravity field model
