GOCE引力梯度内部校准方法  

Internal calibration method of GOCE gravity gradients

作　　者：潘娟霞 邹贤才[1,2] PAN Juanxia;ZOU Xiancai(School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, China;Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, Wuhan University, Wuhan 430079, China)

机构地区：[1]武汉大学测绘学院,湖北武汉430079 [2]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

出　　处：《测绘学报》2022年第2期192-200,共9页Acta Geodaetica et Cartographica Sinica

基　　金：国家自然科学基金(41874021,42192532,41721003);民用航天“十三五”技术预先研究项目。

摘　　要：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。The accurate calibration of the GOCE gravity gradiometer is one of the premises for determining the earth's gravity field model with high precision.L1b dataset of GOCE gradiometer and star sensors are used in the internal calibration.The combination of different star sensors by least-squares adjustment can prevent the propagation of the less accurate component due to the reference frame transformation,thus the accuracy of angular rates used by internal calibration can be improved.In this paper,GOCE data in November 2009 are used to verify the ESA's calibration method.On this foundation,considering the rotation matrices between star sensors and gradiometer are time-varying,improved calibration model is presented by using parameters of the rotation matrices.The analysis shows that the parameters are about 100 arcseconds with a liner drift of 3~30 arcseconds in this month.Based on ESA's internal calibration model considering parameters of three accelerometer pairs,a calibration by using transformation matrix from star sensors to gradiometer and the parameters of three accelerometer pairs is presented in this paper.The accuracy of gravity gradients after calibration shows the effectiveness of this method below frequency of 0.005 Hz.Possible developments of GOCE gradiometer calibration based on this method are discussed in this paper which provides foundation for processing of GOCE and other gravity satellites.

关 键 词：GOCE 引力梯度 加速度计 内部校准 姿态重建 

分 类 号：P228[天文地球—大地测量学与测量工程]