Time synchronization method based on intersatellite bidirectional distance measurement

Abstract

The invention discloses a time synchronization method based on intersatellite bidirectional distance measurement. The time synchronization method comprises the steps of performing modeling on clock correction of a clock through a quadratic polynomial; considering effect of frequency variations, making a satellite-borne atomic clock model adopt three state components, and establishing a state equation of filtering; performing pseudorange measurement on two satellites establishing an intersatellite link in a constellation through an intersatellite bidirectional distance method, and establishing an observation equation; performing Kalman filtering according to the state equation and the measurement equation of the system; performing synchronous filtering on time through centralized Kalman filtering or decentralized Kalman filtering; analyzing effect of the quantity of the intersatellite links on time synchronization accuracy, and selecting the scheme with the highest cost performance according to comparison of simulation results under different quantities of the intersatellite links. By means of comparison of centralized filtering and decentralized filtering and comparison of filtering accuracy under different quantities of the intersatellite links, referential experimental schemes are put forward, and measurement synchronization accuracy is improved.

Description

technical field [0001] The invention belongs to the field of inter-satellite time synchronization, and specifically relates to a method for realizing time synchronization based on Kalman filtering. Background technique [0002] The precise orbit determination of geosynchronous orbit satellite GEO has always been a difficult and hot issue in the field of precision orbit determination. Its geostatic characteristics make the geometric configuration of the ground observation almost unchanged, and the dynamic constraint information of the satellite relative to the ground is very weak. Therefore, in the orbit determination of GEO satellites based on pseudo-range observations, it is impossible to effectively estimate the combined satellite-ground clock error. It needs the support of satellite-ground time synchronization and inter-station time synchronization. [0003] The so-called time synchronization means that the clock deviation of each node in the time synchronization network...

AI Technical Summary

Problems solved by technology

Its geostatic characteristics make the geometric configuration of the ground observation almost unchanged, and the dynamic constraint information of the satellite relative to the ground is very weak. Therefore, in the orbit determination of GEO satellites based on pseudo-range observations, it is impossible to effectively estimate the combined satellite-ground clock error. Support for satellite-to-ground time synchronization and inter-station time synchronization is required

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