摘要
高精度重力梯度观测数据L1级构建的系统方法是推进我国自主重力卫星任务重要的基础数据处理技术.本文以GOCE卫星L1级数据预处理技术和关键载荷原始数据为参考,面向我国发展的梯度测量卫星的任务需要,系统研究并初步实现了卫星重力梯度观测数据L1级构建方法,主要包括加速度计电压数据转换、多星敏感器联合姿态数据的角速度重建、卫星重力梯度分量构建等技术内容.计算结果表明,加速度计超灵敏轴精度为10^(-10)~10^(-11) m·s^(-2)·Hz^(-1/2),达到重力梯度仪设计精度要求;多星敏感器联合解算最佳姿态角速度w y、w z在10~100 mHz内精度约提升1个量级,其精度约达到10^(-5) rad·s^(-1)·Hz^(-1/2)量级,能够有效抑制低精度角速度分量在坐标系转换中导致的噪声传播;基于维纳滤波方法恢复的角速度在5~100 mHz频段内的平方根功率谱密度提升了(5.21~6.56)×10^(-11) rad·s^(-1)·Hz^(-1/2),显示了基于高精度角速度解算重力梯度分量的必要性;构建重力梯度各分量计算值与全球重力场和海洋环流探测器(GOCE)官方公布的重力梯度分量精度相当,其梯度张量的迹在20~100 mHz频段范围内约为10 mE·Hz^(-1/2),验证了本文构建方法的有效性.研究工作可为下一步我国推进实施民用重力梯度测量卫星任务提供自主的原始数据处理技术支撑与储备.
The L1 level construction method of high-precision satellite gravity gradiometry observations is an important basic data processing technology for promoting the national gravity satellite mission.Base on the GOCE satellite pre-processing technology and raw data,the L1 level construction method of satellite gravity gradiometry observation is studied and initially implemented in this work,which aim for the needs of the national gravity gradiometry satellite mission.The main steps include the conversion of the accelerometer voltage data,the reconstruction of the angular rate based on the combination of the star sensors,and the construction of the gravity gradient of the satellite.The results indicate that the accuracy of the accelerometer ultra-sensitive axis is 10^(-10)~10^(-11) m·s^(-2)·Hz^(-1/2),which achieve the designed accuracy requirements of the gradiometer.The optimal determination of the angular rate w y,w z is improved by about 1 order of magnitude in the range of 10~100 mHz at about 10^(-5) rad·s^(-1)·Hz^(-1/2),which is effective in suppressing noise propagation caused by low precision angular velocity components in coordinate system conversions.The square root power spectrum of the angular rate reconstruction based on the Wiener filtering method in the 5~100 mHz band is enhanced by(5.21~6.56)×10^(-11) rad·s^(-1)·Hz^(-1/2),which indicates the necessity of solving the gravity gradient based on high accuracy angular rate.Lastly,the calculated values for each component of the gravity gradient are of comparable accuracy to the official GOCE gravity gradient components.The trace of the gradient tensor is about 10 mE·Hz^(-1/2) in the frequency range of 20~100 mHz,which validates our method.This work provides the technical support and reserve of independent raw data processing for promoting the national civil gravity gradiometry satellite mission.
作者
吴云龙
郭泽华
肖云
马林
WU YunLong;GUO ZeHua;XIAO Yun;MA Lin(Key Laboratory of Earthquake Geodesy,Institute of Seismology,China Earthquake Administration,Wuhan 430071,China;College of Disaster Prevention Science and Technology,Hebei Sanhe 065201,China;National Observation and Research Station of Gravitation and Earth Tide,Wuhan 430071,China;Xi′an Research Institute of Surveying and Mapping,Xi′an 710054,China;DFH Satellite Co.Ltd,Beijing 100094,China)
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第12期4437-4448,共12页
Chinese Journal of Geophysics
基金
国家自然科学基金项目(41931074,41974096)
国家重点研发专项(2018YFC1503503-1)资助.
关键词
卫星重力梯度
预处理
星敏感器
角速度重建
重力梯度数据构建
Satellite gravity gradiometry
Pre-process
Star sensor
Angular rate reconstruction
Gravity gradient construction
