Design and Implementation of High Precision Clock Synchronization for LEO Constellation Based on GNSS

In this paper, a satellite-based clock taming scheme base on GNSS is proposed to address the demand for high precision autonomous clock synchronization technology for LEO satellites. Establish a clock phase-locked loop inside the stand-alone machine by configuring a modular clock board, so that the 1 PPS signal obtained by the GNSS receiver processing maintains a small phase difference with the navigation star 1 PPS signal for a long time; the tamed 10 MHz signal is also used as the sample clock signal for base-band processing. After testing and verification, the accuracy of the tamed 1 PPS signal is better than 10ns, the accuracy of the 10MHz clock signal is better than ≤ 7E−12, the stability of 1s is better than ≤ 7E−12, and the phase noise meets the requirements of other payloads on the satellite. This solution provides an economical and efficient solution for autonomous clock synchronization of distributed constellations.