在波分复用(WDM)光纤网络中,存在很多因素会造成信道间的功率差异。针对波分复用光网络中功率均衡的需求,提出了利用带有不平衡放置的损耗结构的非线性光纤环镜(NOLM)来实现多信道功率均衡的技术方案。理论上分析了该方案利用自相位调制(SPM)效应产生均衡作用的基本原理,指出了该方案所能达到的最佳均衡指标。通过两波长10 Gb/s幅度调制信道的实验,观察了不平衡损耗结构非线性光纤环镜(L-NOLM)的输出功率的变化过程,验证了它的均衡效果,当输入信道功率差异为7 dB时,输出信道功率最大差异不超过2 dB。该方案结构简单,无需解复用、复用,响应速度快,具有自适应均衡的特点。

To meet the equalization requirements in wavelength-division multiplexing (WDM) networks, a channel power equalization method by using nonlinear fiber loop mirror (NOLM) with an unbalance loss is proposed. The operation principle based on self-phase modulation (SPM) effect is explained and the best achievable performance is given from the analysis results. The equalization function of the NOLM is demonstrated via a two-channel experiment with 10 Gb/s amplitude modulation. The variations of output power of the NOLM are observed and the results show that when the input power difference is 7 dB, no more than 2 dB of output power difference is achieved. This method is attractive because of the advantages of no requirement of demultiplexing and multiplexing, simple structure, self-adaptability and high response speed.