High-precision relative distance measurement and time synchronization method based on inter-satellite link

Abstract

The invention discloses a high-precision relative distance measurement and time synchronization method based on an inter-satellite link, aiming to provide a distance measurement and time synchronization with high measurement accuracy. The present invention is realized through the following technical solutions: the inter-satellite link is established based on the respective satellite carrier frequency standards of two satellites A and B respectively, and the speed measurement information and clock error are incorporated into the dynamic error model; In the receiving time slot, capture, track, and demodulate the received signal of the other party, recover the information frame, and calculate the local pseudorange when the epoch is sent in conjunction with the other party's measurement time slot; finally, the A star and the B star will respectively correct The subsequent pseudorange is embedded in the local baseband data and sent to the other party. The two satellites independently use the locally measured corrected pseudorange and the other party’s corrected pseudorange demodulated from the received information frame to obtain the inter-satellite relative distance value and time difference, adjust the clocks of the two satellites, and correct the satellite ephemeris and clock parameters.

Description

technical field [0001] The invention relates to a high-precision relative ranging and time synchronization method based on an inter-satellite link. Background technique [0002] The research work of satellite inter-satellite link was carried out relatively early abroad, and it has been widely used in the world, mainly used in GPS satellite navigation system, tracking and data relay satellite system, communication system, medium and low orbit communication Satellite network systems, ocean and ground observation satellite systems, etc. At the same time, with the development of small satellites, in order to maintain the configuration of satellite formation flight, distance measurement, time synchronization and control command transmission between satellites are required. Therefore, it is very necessary to establish a reliable inter-satellite link. The inter-satellite link is used to realize inter-satellite communication, complete fault detection and processing, operation manag...

AI Technical Summary

Problems solved by technology

Although the two-way comparison method eliminates the influence of the propagation path and improves the measurement accuracy, the inter-satellite two-way time synchronization comparison based on the inter-satellite link is calculated by using the measured value of the two-way pseudo-range at the same moment of the link The clock difference value at this moment is difficult to measure absolutely simultaneously in actual engineering. During the interval period, the high-speed relative motion between the two stars will cause the distance between the two to change, which will eventually cause errors in the calculated clock difference value.

Images