Gravity satellite east-west direction differential observation data construction and inversion method and system

Abstract

The invention relates to a gravity satellite east-west direction differential observation data construction and inversion method and system. The method comprises the following steps: carrying out datainterpolation and gridding processing on the basis of the observation data measured by a GNSS and the observation data of an accelerometer, carrying out difference processing on the positions, speedsand accelerations of a plurality of adjacent grid points in the east-west direction to obtain east-west differential observation data, further constructing an observation equation based on the east-west differential observation data, performing respective time-varying field calculation on north-south and east-west observation equations, finally performing spectral combination calculation on north-south and east-west gravitational field models, and calculating a final time-varying gravitational field model. The east-west observation data construction and inversion technology can effectively solve the problem of south-north stripes of a satellite inversion gravity field, thereby improving the gravitational field calculation precision. Compared with other methods, the algorithm provided by the invention is simple to implement, and the stability and reliability of the gravitational field calculation result can be ensured on the whole.

Description

technical field [0001] The invention relates to the field of satellite gravity field inversion, in particular to a method and system for constructing and inversion of gravity satellite east-west direction differential observation data. Background technique [0002] The earth's gravitational field is a basic physical field that reflects the distribution, movement, and mass change of the earth's matter. Accurately determining the fine structure of the earth's gravitational field and its temporal and spatial changes is of great importance in the fields of geophysics, geodesy, national defense science, and economic construction. practical value and significance. The use of satellites for gravity field detection is the most effective means to obtain high-quality gravity field models, and it has also become a hot technology for geospace detection. The main methods of retrieving the earth's gravity field using gravity satellite data are energy method, dynamic method and accelerati...

AI Technical Summary

Problems solved by technology

Second, there is anisotropy problem of time-varying gravity field

The GRACE satellite adopts the low-satellite tracking satellite observation mode in a near-polar circular orbit. The sub-satellite point trajectory presents the characteristics of dense orbits in the polar region and sparse orbits in the equatorial region. The inter-satellite distance variability observation value is the main observation quantity of the time-varying gravity field, resulting in This shows that the satellite is more sensitive to changes in the gravity field in the north-south direction, resulting in a north-south strip error

[0004] For the steady-state gravity field, the limitations of current gravity satellite missions are mainly reflected in the inability to substantially reduce the altitude of the satellite flight orbit and improve the measurement accuracy of the accelerometer and other key loads

For the time-varying gravity field, it mainly relies on the GRACE satellite mission to realize it. The main disadvantage is that the limitations of the observation mode and spatial resolution cause the north-south strip error and the aliasing of space-time frequency.

Images