Abstract

We have demonstrated accurate frequency transfer via an ultra long span optical-fiber link by passive phase conjugation, which is based on frequency mixing. Combing with the phase-lock-loop, our compensation technique can eliminate the effect of phase noise that introduced during the optical-fiber transmission, so the phase of remote signal is synchronized to the phase of local reference signal. The transfer stability of our experiment with 2.4 GHz frequency signal through a 1007 km fiber link is 6.9×10^-14/s and 4.1×10^-16/10⁴s.

© 2018 The Author(s)