Error analysis for satellite gravity field determination based on two-dimensional Fourier methods

摘要

The time-wise and space-wise approaches are generally applied to dataprocessing and error analysis for satellite gravimetry missions. But both theapproaches, which are based on least-squares collocation, address the wholeeffect of measurement errors and estimate the resolution of gravity fieldmodels mainly from a numerical point of indirect view. Moreover, requirementfor higher accuracy and resolution gravity field models could make thecomputation more difficult, and serious numerical instabilities arise. In orderto overcome the problems, this study focuses on constructing a directrelationship between power spectral density of the satellite gravimetrymeasurements and coefficients of the Earth's gravity potential. Based ontwo-dimensional Fourier transform, the relationship is analytically concluded.By taking advantage of the analytical expression, it is efficient and distinctfor parameter estimation and error analysis of missions. From the relationshipand the simulations, it is analytically confirmed that the low-frequency noiseaffects the gravity field recovery in all degrees for the instance of satellitegradiometer recovery mission. Furthermore, some other results and suggestionsare also described.