基于Sagnac干涉仪的级联型梳状滤波器

A Cascaded Comb Filter Based on Sagnac Interferometer

密集波分复用(DWDM)系统光信道数量的增加,使得与DWDM技术有关的各种光学滤波器技术成为当前光纤通信领域的研究热点。高双折射(HiBi)光纤环具有易于制作、性能稳定以及良好的滤波特性等特点,近年来受到广泛关注;通过增加Sagnac环内HiBi光纤和偏振控制器的个数,或者采用多个HiBi光纤Sagnac环的级联形式,可使输出的反射谱和透射谱的谱宽和中心波长调谐得更为精细。推导了HiBi光纤、耦合器以及偏振控制器的Jones矩阵,利用Jones矩阵理论对基于HiBi光纤和Sagnac环的滤波器的传输矩阵进行了理论分析,分析并设计了两种高阶级联的HiBi光纤Sagnac环的可调谐梳状滤波器,通过调节压电陶瓷(PZT)实现对HiBi光纤相位的控制,最终实现对基于HiBi光纤Sagnac干涉仪的梳状滤波器中心波长调谐的目的。

With the increase of optical channels in DWDM systems various optical filters related DWDM applications become a hot topic in the field of optical fiber communications.High birefringence（HiBi） fiber Sagnac loops have attracted widespread attention in recent years due to their simple structure,stable performance and perfect comb filtering characteristics;and to increase the number of HiBi fiber and polarization controller in Sagnac loop,or connect multiple Sagnac loops together can make the tuning of spectrum width and central wavelength of the reflection spectrum and transmission spectrum more precise.The Jones matrixes of HiBi fiber,coupler,and polarization controller are deduced;the transmission matrixes of the filters that are based on HiBi fiber and Sagnac loop are analyzed theoretically;and two high level and cascaded tunable comb filters based on HiBi fiber and Sagnac loop are analyzed and designed.Through controlling the phase of HiBi fiber by adjusting PZT,the tuning of the central wavelength of the comb filter based on HiBi fiber Sagnac interferometer is realized.