环形谐振器辅助FBG对的微波光子滤波器的研究

Study on microwave photonic filters based on a pair of FBG assisted by a ring resonator

在深入研究微波光子滤波器理论的基础上,将环形谐振器与FBG(光纤布拉格光栅)对相结合,提出一种环形谐振器辅助FBG对的微波光子滤波器。通过合理设置其结构参数,得到了具有最大平坦滤波响应的微波光子滤波器。利用信号流程图对其进行了详细的理论分析,得到了该结构的微波光子滤波器的系统传输函数。并用MATLAB软件仿真分析了耦合器的耦合系数、FBG对的反射率、光纤环长度和增益对系统传输特性的影响。结果表明,这种滤波器的结构是有效和可行的,在微波和毫米波光纤系统中有着潜在的应用价值。

A Microwave Photonic Filter （MPF） with a pair of Fiber Bragg Grating （FBG） assisted by a ring resonator is pro- posed on the basis of the in-depth study of the MPF theory. An MPF with the maximum flat filtering response is obtained by optimizing its structural parameters and the system transfer function of such a MPF is acquired on the basis of the detailed anal- ysis by using a signal flow graph. The effects of the coupling coefficient, the reflectivity of the pair of FBG, the length and the gain of the fiber ring on the system transmission characteristics are analyzed by using the MATLAB software. The results show that this filter with such a structure is effective and feasible and has potential applications in microwave and millimeter- wave fiber-optic systems.