双光纤光栅级联Sagnac环多波长滤波系统研究

Research on multi-wavelength filtering system of dual fiber Bragg grating cascaded Sagnac loop

摘要:

为了实现可调谐的高精度滤波并扩大通信容量,本文设计了一种创新的滤波器系统方案,采用了双光纤布拉格光栅级联和Sagnac环的结合。该方案经过Jones矩阵理论的深入分析和数值仿真验证。在波长范围为1 554—1 570 nm的频带范围内,通过调整光纤臂长差来引入Sagnac相移,从而实现了可调谐性。此设计不仅增加了滤波通道数目,而且减小了半高全宽。值得注意的是,在相同的臂长差条件下,此系统相较于单个光纤光栅和Sagnac环的滤波器,精度有了显著提高。在功率损耗为8 dB的情况下,此滤波器系统允许高达196 nm的臂长误差容限,同时提供更为精确的透射谱,实现调谐更加简便。此滤波器系统具备易实现性,广泛适用于密集波分复用系统以及光通信等领域。

Abstract:

In order to achieve tunable high-precision filtering and expand communication capacity,this paper presents an innovative filtering system approach that combines dual optical fiber Bragg gratings cascaded with a Sagnac loop.This approach has undergone in-depth analysis and numerical simulation validation using Jones matrix theory.Within the wavelength range from 1 554 nm to 1 570 nm,tunability is achieved by adjusting the length difference between the optical fiber arms to introduce Sagnac phase shifts.This design not only increases the number of filtering channels but also reduces the full width at half height.It is worth noting that under the same arm length difference conditions,this system exhibits a significant improvement in precision compared with single fiber Bragg gratings and Sagnac loop filters.With a power loss of 8 dB,this filtering system allows for an arm length error tolerance of up to 196 nm while providing a more accurate transmission spectrum,making tuning more convenient.This filtering system is easy to implement and widely applicable in dense wavelength division multiplexing systems and the field of optical communication.