  The time-wise and space-wise approaches are generally applied to data
processing and error analysis for satellite gravimetry missions. But both the
approaches, which are based on least-squares collocation, address the whole
effect of measurement errors and estimate the resolution of gravity field
models mainly from a numerical point of indirect view. Moreover, requirement
for higher accuracy and resolution gravity field models could make the
computation more difficult, and serious numerical instabilities arise. In order
to overcome the problems, this study focuses on constructing a direct
relationship between power spectral density of the satellite gravimetry
measurements and coefficients of the Earth's gravity potential. Based on
two-dimensional Fourier transform, the relationship is analytically concluded.
By taking advantage of the analytical expression, it is efficient and distinct
for parameter estimation and error analysis of missions. From the relationship
and the simulations, it is analytically confirmed that the low-frequency noise
affects the gravity field recovery in all degrees for the instance of satellite
gradiometer recovery mission. Furthermore, some other results and suggestions
are also described.
