一种基于取样光栅的Sagnac环滤波器的设计研究

摘要

To explore new structures of comb filters, a new Sagnac loop filter based on the sampled fiber Bragg grating was proposed. Using the theory of Jones matrix, the theoretical model of filter was established. Theoretical analysis and numerical simulation of transmission spectra of the proposed filter were carried on. By choosing the different value of the sampled fiber Bragg grating length L, optical fiber ring arm length difference ΔL, and the sampling period P, six kinds of narrow-band comb transmission spectrums with discrete spectral lines, high reflectivity, and equal interval can be obtained. The spectrums have good wavelength selectivity and good channel isolation. The simulation results show that this filter can be used in the multi-channel narrow band filter of the wavelength division multiplexing system, dual-wavelengthfiber laser, and the distributed sensing system, etc. It provides a certain reference for the filter combining fiber Bragg grating with the structure of the Sagnac loop in research and application.%为了探究更多新结构的梳状滤波器,采用了一种新型的基于取样光栅的Sagnac环滤波器的设计方案.利用Jones矩阵理论,建立了该滤波器的理论模型,并对其传输光谱进行了分析和数值仿真.通过选取不同的光纤光栅的长度L、光纤环臂差ΔL和取样周期P等参量的值,可以得到6种具有分立谱线、高反射率、等间隔的窄带梳状透射谱,且具有良好的波长选择性和信道隔离度.结果表明,这种滤波器可应用于波分复用系统的多通道窄带滤波器、双波长的光纤激光器和分布式传感系统等,对结合光纤光栅和Sagnac环结构的滤波器的研究和应用提供了一定的参考.