不同指向模式下星载冷原子梯度仪对重力场解算精度的影响  

Effects of onboard cold-atom interferometry gradiometer in different pointing modes on the gravity field recovery

作　　者：穆庆禄 王长青 闫易浩 钟敏[4] 冯伟[4] 梁磊 朱紫彤 MU QingLu;WANG ChangQing;YAN YiHao;ZHONG Min;FENG Wei;LIANG Lei;ZHU ZiTong(State Key Laboratory of Geodesy and Earth's Dynamics,Innovation Academy for Precision Measurement Science and Technology,Chinese Academy of Sciences,Wuhan 430077,China;College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Max-Planck-Institut für Gravitationsphysik(Albert-Einstein-Institut)and Institut für Gravitationsphysik,Leibniz Universität Hannover,Hannover 30167,Germany;School of Geospatial Engineering and Science,Sun Yat-Sen University,Zhuhai Guangdong 519082,China;School of Geographic Information and Tourism,Chuzhou University,Chuzhou Anhui 239000,China)

机构地区：[1]中国科学院精密测量科学与技术创新研究院,大地测量与地球动力学国家重点实验室,武汉430077 [2]中国科学院大学地球与行星科学学院,北京100049 [3]马克斯-普朗克引力物理研究所(阿尔伯特-爱因斯坦研究所)和汉诺威莱布尼兹大学引力物理研究所,德国汉诺威301674 [4]中山大学测绘科学与技术学院,广东珠海519082 [5]滁州学院地理信息与旅游学院,安徽滁州239000

出　　处：《地球物理学报》2024年第7期2528-2545,共18页Chinese Journal of Geophysics

基　　金：国家自然科学基金(42061134010,42174103,42027802,42204091);湖北省自然科学基金计划杰出青年人才项目(2019CFA091);国家留学基金委资助。

摘　　要：冷原子干涉测量技术(CAI, Cold-Atom Interferometry)的发展为未来卫星重力梯度测量任务提供了新的测量思路.目前基于该任务概念的模拟研究均基于单一的观测指向模式对CAI梯度仪的对地观测能力进行论证.本文在GOCE卫星任务背景下,通过数值闭环模拟评估了CAI梯度仪在近地指向和惯性指向模式下对重力场观测影响.实验结果表明:在近地指向观测模式下,CAI梯度仪受卫星旋转角速度的影响,重力场解算的精度仅在50阶以内优于GOCE卫星的模拟结果.若当卫星搭载轨道旋转补偿系统时可以有效地减弱卫星旋转对CAI梯度仪的影响,进而提高重力场模型的解算精度.梯度张量主对角线三分量的联合解算精度在全频段内都要优于GOCE卫星相应分量的结果,精度可提高1.5~6倍.在惯性指向观测模式下且仅考虑卫星残余角速度的影响时,CAI梯度仪的解算结果在30阶以后比GOCE卫星所搭载的GRADIO梯度仪的精度低.而在综合考虑卫星残余角速度和卫星轨道面旋转后,解算得到的重力场在100阶以内优于GOCE卫星解算精度.进一步比较两种指向模式下分别基于单轴、双轴和三轴观测的结果可以发现,三轴观测时两种指向模式的解算精度相当,在所有阶次上都要优于GRADIO梯度仪的结果.但基于单轴进行观测时,近地指向模式下V_(zz)分量的精度更高,而对于双轴观测的情况,惯性指向下的组合(V_(xx)+V_(zz)和V_(yy)+V_(zz))解算精度更高.本研究通过对不同指向模式下CAI梯度仪对地观测影响的分析,可为基于CAI梯度仪的新型空间量子-地球重力场测量任务提供相应的参考.The development of Cold-Atom Interferometry(CAI)provides new measurement ideas for future satellite gradiometry missions.Current simulation studies based on this mission concept have only demonstrated the ability of the CAI gradiometer to observe the Earth's gravity field on a single pointing mode.In this paper,numerical closed-loop simulations are conducted to evaluate the effect of different pointing modes of the CAI gradiometer on the gravity field recovery in the context of the GOCE mission.The simulation results show that in the nadir pointing mode,the accuracy of the gravity field solution of the CAI gradiometer is better than that of the GOCE within 50 d/o(d/o=degree and order)only,which is due to the influence of the satellite rotation angular velocity.When the satellite is equipped with the orbital rotation compensation scheme,the influence of the satellite rotation on the CAI gradiometer can be effectively attenuated,and then the accuracy of the gravity field solution can be improved.The combined accuracy of the three main diagonal components of the gravity gradient tensor is better than the results from the GOCE satellite in the full frequency band by a factor of 1.5 to 6.In the inertial pointing mode and considering only the effect of satellite residual angular velocity,the solution of the CAI gradiometer is less accurate than the GRADIO gradiometer on board the GOCE satellite after 30 d/o.Taking into account the residual angular velocity of the satellite and the rotation of the satellite orbital plane,the CAI gradiometer solves the gravity field with better accuracy than the GOCE satellite solution within 100 d/o.We further compared the results of the two pointing modes based on single-axis,dual-axes and tri-axes observations,respectively.It can be found that the overall accuracy of the two modes is comparable for tri-axes observations and outperform the result of the GRADIO gradiometer at all degrees and orders.However,when the observations are based on single-axis,the accuracy of the V_(zz) compone

关 键 词：地球重力场 GOCE 冷原子梯度仪 近地指向 惯性指向 

分 类 号：P228[天文地球—大地测量学与测量工程]