Long-term stability of frequency transfer over an urban fiber link using microwave phase compensation

摘要

We report a novel system for highly stable 100 MHz mode locked pulse as a reference frequency signal transfer through a round trip 20 km urban fiber link. An electronic approach for compensating the fluctuations introduced by the link is proposed and implemented. The rms phase fluctuation was reduced from 75 mrad (118ps) to 4 mrad (6.3ps) in 48 hours, and the frequency stability was improved by three orders of magnitude in the measurement time.