LI Xiao-feng1,2, LIANG Shuang-you1, ZHANG Shou-gang1

(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: In order to improve the precision of time/frequency transfer via fiber, a method of digital phase compensation is proposed. In this method, the signal phase difference between sender and receiver is digitized by a single-chip microcomputer, and the signal phase of sender is shifted by a digital phase shifter, so as to decrease the signal phase difference and complete the phase precompensation, thereby improving the precision of time/frequency transfer. The experiments show that the phase difference between sender and receiver can be decreased to less than 5 degree.

Key words: fiber; time/frequency transfer; digital phase shifter; precompensation