DONG Shao-wu1，QI Yi1，LIU Chun-xia1，WANG Gai-xia1，YUAN Hai-bo1,2，Li Wei1,2

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

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

Abstract: The micro-wave time transfer system between Lintong and Pucheng has been used to synchronize the time signal from the time-keeping clock room（located in Lintong）and the signal from the broadcast control clock room（located in Pucheng）for over 28 years till the end of 2006. The reliability and the specifications for this time transfer system have been seriously degraded mainly due to the ageing of the device. The technical transformation scheme for the micro-wave time transfer system and the realized function of the digital micro-wave system are introduced briefly. The preliminary results show that the performance of the transformed micro-wave time transfer system has been improved.

Key words: timekeeping；micro wave communication；time transfer；precision