Precise synchronization between radio frequency and mode-locked laser pulses provides a high resolution capability for detecting either time jitter in laser pulse train or phase noise in radio frequency. In this talk, we will present our recent progresses on radio frequency dissemination and fiber optical sensing based on sub-femtosecond level synchronization between radio frequency and mode-locked pulse train.
We report on a new phase noise detection technique for radio frequency (RF) dissemination based on transferring mode
locked laser pulses via optical fiber. The proposed approach is insusceptible to optical fiber interconnection reflection by
combining optical frequency comb (OFC) expansion generated by four wave mixing (FWM) in dispersion shifted fiber
(DSF) and wavelength division multiplexing (WDM) technique. An experimental system based on a fiber link of 100km
was demonstrated. The measured fractional stability was 1.5×10<sup>-13 </sup>at 1s and 1.7×10<sup>-16 </sup>at 1000s.