An Analysis on Requirements of Orbital Parameters in Satellite-to-Satellite Tracking Mode

Based on the semi-analytical method and using the combined model whose accuracy on the accumulative geoid is influenced by the error of the inter-satellite velocity of the GRACE (Gravity Recovery and Climate Experiment) binary in the K band, the orbital error of the GPS receiver and the error of the non-conservative force of the accelerometer, we have for the first time carried out an analysis on the requirements of the orbital parameters in the SST (satellite-to-satellite tracking) mode. We suggest that it would be better for the first gravity satellite of our country the average orbital altitude and inter-satellite distance will be designed, respectively, as 400 km and 220 km. This study may not only provide a theoretical basis and calculational guarantee for the optimal selection of the orbital parameters in the program of satellite gravimetry of our country in the future as well as the efficient and quick estimation of the accuracy of the global gravitational field, but also possess certain guiding significance on the orientation of the development of the future international programs of the GRACE Follow-On terrestrial gravimetry and the GRAIL (Gravity Recovery and Interior Laboratory) lunar gravitational exploration.