Algorithm Characteristics of Dynamic Approach-based Satellite Gravimetry and Its Improvement Proposals

• Main Author: SHEN Yunzhong
• Format: Article
• Language: zho
• Published: Surveying and Mapping Press 2017-10-01
• Series: Acta Geodaetica et Cartographica Sinica
• Subjects: satellite gravimetry; dynamic approach; orbit integration; analytic orbit; linearization method
• Online Access: http://html.rhhz.net/CHXB/html/2017-10-1308.htm
• ISSN: 1001-1595; 1001-1595

By using the integration equation for computing satellite orbit, this paper derives the observational equation for computing gravity field model linearized with respect to the reference orbit, provides the integration equation of calculating the design matrices of the observational equation, and clarifies that the dynamic approach is in principle the perturbation method relative to the reference orbit, therefore the initial partial derivatives with respect to the force model parameters must be zero. Based on the derived formulae this paper analyzes the main characteristics of dynamic approach-based observational equation, i.e. the linearization error will rapidly increase and the property of observational equation becomes worse as the integration arc extends longer, and the numerical integration error will be the bottle-neck problem for the data processing of next generation of satellite gravity exploration. Then this paper proposes the methods for improving the accuracy of gravity recovery, which can be summarized as that refining the linearization method relative kinematic orbit to reduce the linearization error, modifying parameterization method to improve the property of observational equation, and combined using analytic formula and numerical integration formula to increase the accuracy of orbit computation.