波分复用光时分复用波长转换信号的消光比研究

Study on Signal Extinction Ratio in WDM-OTDM Wavelength Conversion

对基于半导体光放大器(SOA)交叉增益调制(XGM)效应的全光波分复用光时分复用(WDMOTDM)转换后的两路时分复用输出信号的消光比(ER)特性进行了分析。研究了两路波分复用的输入抽运光和探测光的功率、波长、抽运光的消光比、数据速率以及半导体光放大器的偏置电流、腔长和模场限制因子对转换信号消光比的影响。模拟结果表明,增大抽运光输入功率,选择长波长抽运光,可以增加转换光相应信道消光比,但减小了相邻信道的输出消光比;增加抽运光消光比,可以提高转换光消光比,但各个信道增长幅度不同;减小探测光输入功率,选取短波长探测光波长,增加半导体光放大器的腔长和模场限制因子以及大的偏置电流可提高转换光消光比;对于两路或多路波分复用信号转换时分复用信号的过程中,一定要考虑转换光每个信道消光比的均衡。

The extinction ratio performance of converted two channel time division multiplexing output signals in all optical WDM (wavelength division multiplexing) OTDM (optical time division multiplexing) converter based on cross gain modulation (XGM) in semiconductor optical amplifier (SOA) is analyzed .The effects on the extinction ratio of converted signal is studied regarding to various parameters such as the power and wavelength of two channel WDM input pump and probe, the bit rate, the extinction ratio of the pump, the SOA bias current, cavity length, and confinement factor. Which can provide the theoretical basis for the optimization of wavelength converter and signal processing in WDM switching nodes. It is shown by numerical simulation that high pump input power and long pump wavelength enhance signal extinction ratio of corresponding channel but decrease the adjacent channel extinction ratio. High pump extinction ratio can do too, however, the increasing amplitudes of different channels are different. Meanwhile extinction ratio of converted signal can be improved with low probe power, short probe wavelength, long cavity length, high confinement factor, and large biased current. Especially extinction ratio equalization of each channel should be considered in all optical WDM OTDM wavelength conversion.