基于半导体光放大器四波混频效应的多种调制格式的波长转换实验

实验报道了利用半导体光放大器(SOA)的四波混频(FWM)效应实现多种码型的波长转换.其中对于非归零(NRZ)信号实现了从单信道到三信道的多波长转换.调制速率从10 Gb/s到40 Gb/s均实现多波长转换.对于归零(RZ)信号分别实现了20 Gb/s和40 Gb/s的RZ格式的波长转换和40 Gb/s的载波抑制归零(CSRZ)格式的波长转换,利用光纤布拉格光栅(FBG)作为带陷滤波器消除共轭光和抽运光之间的串扰.对于非归零差分相移键控(NRZ_DPSK)信号分别实现了20 Gb/s和40 Gb/s的波长转换,利用实验室自制的光纤延时干涉仪进行NRZ-DPSK信号的解调.基于FWM效应的转换光的输出消光比大于7 dB,转换后消光比退化约为3 dB.

Experimental Study of Wavelength Conversion at Various Modulation Formats Based on Four-Wave Mixing in a Semiconductor Optical Amplifier

The wavelength conversion based on four-wave mixing (FWM) in semiconductor optical amplifier (SOA) for a variety of modulation formats is demonstrated. As for nonreturn-to-zero (NRZ) format, the single-to-triple channel wavelength conversion is reported. The modulation speed varies from 10 Gb/s to 40 Gb/s. As for return-to-zero (RZ) format, the wavelength conversion at 20 Gb/s and 40 Gb/s is realized. As for carrier suppressed RZ (CSRZ) format, the 40 Gb/s wavelength conversion is achieved. A notch filter made by fiber Bragg grating is used to separate the conjugated light and the pump light. As for NRZ-differential phase shift keying (DPSK) format, the wavelength conversion at 20 Gb/s and 40 Gb/s is realized. A home-made fiber delayed interferometer (FDI) is employed to demodulate the converted DPSK signal. The output extinction ratio (ER) of the converted signal based on FWM is higher than 7 dB, and the ER degradation is about 3 dB.