YIN Dong-shan1,2，GAO Yu-ping1，CHEN Ding1，PENG Hui-quan1

(1. National Time Service Center, Chinese Academy of Sciences, Xi’an 710600, China;

2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China) 

Abstract: An algorithm of correcting the clock error for the long-running onboard clock is discussed, in which the millisecond pulsar is used as the frequency source with high stability and the onboard clock is controlled through the Kalman optimum estimation algorithm. The simulation has proved that this algorithm can improve the long-term stability of onboard clock effectively, and can enhance the capability of autonomous long-running for the onboard clock.

Key words: pulsar; Kalman optimum estimation; onboard clock; time