The Analytical Theory Of Space-based Gravity Measurements And Its Realization Method By Satellite Formation

High resolution global gravity field model is the national strategic information resource, which is very important to scientific research, mineral exploration, defense construction. As the most effective means of getting global gravity field model, Space-based Gravity Measurement(SGM) has received increased attention with successful applications. To obtain higher gravity measurement accuracy, the next generation gravity measurements are being studied in the Europe and America. When SGM greatly improves the accuracy of the gravity field model, it is facing a series of theoretical problems to be solved. In this study, the analytical theory for gravity measurement was systematically established. Then based on the satellite formation flying technology, analytical theory and realization methods for gravity field measurement by satellite formation were studied.Firstly, based on the physical principles of SGM, the scientific concept of Space-based Gravitational Sensor(SGS) was proposed, by which SGMs were divided into three kinds, SGM based on the absolute orbit perturbation of SGS, SGM based on e relative orbit perturbation of two SGSs with long and short baselines, respectively. Thus the architecture for studying SGM was established.Secondly, for three kinds of SGMs, the relationship between gravity field measurement performance and orbital parameters, payload capacities was studied, and then based on spectrum analysis, the analytical expression of degree error variance of gravity field measurement with mission parameters as arguments was got, which was used for calculating the highest degree of SGM, geoid error and gravity anomaly error. Furtherly, based on these analytical model of SGMs, the methods for orbit optimization design and payload capacities matching design were proposed, which paved the way for optimization design of SGM mission.Nextly, the inherent relationship among three kinds of SGMs was analyzed and equivalent conversion expressions between mission parameters of any two kinds of SGMs were established, which means that if mission parameters of two kinds of SGMs satisfy this expression, then they have the same gravity field measurement performance. The equivalent conversion expressions were then verified, physical mechanism consistency of three kinds of SGMs was proved, and then unified analytical model for all kinds of SGMs was got. Furtherly, based on SGMs by the relative orbit perturbation of two SGSs with short baselines and equivalent conversion expressions, ideal concepts of relative SGMs with long baselines along the radial and normal direction were proposed, which breaks through the limitation that in traditional gravity field measurements of long baseline relative orbital perturbation there is only measurement along the tracking direction and then expands the scope of SGM, providing an analysis tool for comprehensive application of different SGM ways.Finally, by combining satellite formation flying technology and analytical method of SGM, analytical model for gravity field measurement by satellite formation was established. Then influences of orbital parameters, formation configurations, and payload capacities on gravity field measurement performance were analyzed, and methods for configuration optimization design and payload capacities design as well as basic configurations were proposed, which provided the theoretical basis for mission optimization design of gravity field measurement by satellite formation.In this study, systematic analytical theory for space-based gravity measurement and realization methods for gravity field measurement by satellite formation are obtained, which paves the way for top-level planning and design of gravity field measurement mission in our nation.