All-optical NRZ-DPSK clock recovery using chromatic dispersion induced clock tone

All-optical clock recovery (CR) from 10Gbps non-return-to-zero differential phase-shift-keying (NRZ-DPSK) signal is demonstrated experimentally, with the chromatic dispersion induced clock tone and semiconductor optical amplifier (SOA)-based mode-locked fiber ring laser. The good performance of our proposed configuration is fulfilled with a 20km standard single mode fiber to regenerate clock tone of the NRZ-DPSK signal. The recovered clock signal with the extinction ratio over 17 dB and the root-mean-square timing jitter of 718 fs is achieved under 2(31)-1 pseudorandom binary sequence NRZ-DPSK signals measurement.