All-optical clock extraction from 10-Gbit/s NRZ-DPSK data using modal interference in a two-mode fiber

作者：Jeon Sie Wook; Kim Tae Young; Kwon Won Bae; Park Chang Soo^*

来源：Optics Communications, 2010, 283(4): 522-527.

DOI：10.1016/j.optcom.2009.10.091

All-optical clock extraction from a 10-Gbit/s NRZ-DPSK input signal is demonstrated using modal interference in a two-mode fiber (TMF) and a mode-locked fiber ring laser. The TMF has a Mach-Zehnder configuration with two arms along the core and cladding regions. Using the difference in propagation delay between two arms, the non-return-to-zero differential phase shift keying (NRZ-DPSK) signal is converted to the return-to-zero on-off keying (RZ-OOK) signal. To obtain repetitive pulses as a clock signal from the RZ-OOK signal, a ring laser with a semiconductor optical amplifier (SOA) is used. Subsequently, the carrier-to-noise ratio (CNR) of the RZ-OOK and clock signals are enhanced up to 30 dB and 40 dB, respectively, compared to that of the original NRZ-DPSK signal. Also, the clock signal centered at 10 GHz has a low timing jitter of < 1.6 ps. It is expected that this method can be applied to high speed fiber-optic systems of > 10 Gbit/s due to its small time delay between the core and cladding regions.

• 出版日期2010-2-15