基于光纤布拉格光栅型声光调制器的Ⅴ-Ⅰ传输矩阵法特性分析

发布时间：2018-03-25 17:14

本文选题：光纤布拉格光栅　切入点：声光调制器　出处：《北京交通大学》2015年硕士论文

【摘要】：光纤布拉格光栅型声光调制器以其调谐范围宽、响应速度快、插入损耗小等优点,被广泛应用于光纤通信和光纤传感等领域。快速有效地获得光纤布拉格光栅型光器件的光谱特性,对于优化设计复杂结构的光纤光栅有着重要的意义。本文将工程上广泛使用的V-I传输矩阵法应用于对光纤布拉格光栅型声光调制器的理论分析中,并将该理论应用于非均匀布拉格光栅型声光调制器的特性分析,主要的研究内容如下： 1.对于光纤光栅的四种常见分析方法,即耦合模法、传输矩阵法、傅立叶变换法以及多层膜法进行了详尽的理论推导,并在此基础上建立了分析光纤光栅光谱特性的V-I传输矩阵法模型,与现有的分析方法相比,该模型算法简单、求解更加容易,能够快速得出声光调制器的传输特性。 2.采用V-I传输矩阵法模型,分析了超声波频率和声致应变幅度对均匀光纤布拉格光栅型声光调制器的反射谱的影响,得出了主次反射峰间的波长间隔与超声波频率之间的增长系数为0.145nm/MHz,且反射峰的反射率随着声致应变幅度的改变而呈周期性变化。同时与其他方法比较,突出了V-I传输矩阵法的有效快速性。 3.针对啁啾以及相移两种非均匀光纤布拉格光栅型声光调制器,提出了采用V-I传输矩阵法分析因超声波频率和声致应变幅度引起的折射率分布变化对反射谱的影响,获得了主次反射峰间的波长间隔与超声波频率之间的关系,以及反射峰的反射率与声致应变幅度间的变化规律。并利用剪切模PZT产生纵向声波,使用频率为2MHz的超声波对啁啾光纤布拉格光栅进行调制,实验结果与仿真结果相致。
[Abstract]:Fiber Bragg grating type acousto-optic modulator has the advantages of wide tuning range, fast response speed and low insertion loss. It is widely used in optical fiber communication and optical fiber sensing. It is very important to obtain the spectral characteristics of fiber Bragg grating devices quickly and effectively for optimizing the design of fiber Bragg grating with complex structure. In this paper, the V-I transfer matrix method widely used in engineering is applied to the theoretical analysis of fiber Bragg grating type acousto-optic modulator, and the theory is applied to the characteristic analysis of non-uniform Bragg grating type acousto-optic modulator. The main contents of the study are as follows:. 1. Four common analysis methods of fiber grating, namely coupling mode method, transmission matrix method, Fourier transform method and multilayer membrane method, are derived in detail. A V-I transmission matrix model for analyzing the spectral characteristics of fiber Bragg gratings (FBG) is established. Compared with the existing analysis methods, the proposed model is simpler and easier to solve, and the transmission characteristics of the acousto-optic modulator can be obtained quickly. 2. The influence of ultrasonic frequency and acousto-induced strain amplitude on the reflectance spectrum of the uniform fiber Bragg grating type acousto-optic modulator is analyzed by using V-I transmission matrix method. The growth coefficient between the wavelength interval between the primary and secondary reflection peaks and the ultrasonic frequency is 0.145 nm / MHz, and the reflectivity of the reflection peak changes periodically with the change of the amplitude of the acoustic strain. At the same time, it is compared with other methods. The efficiency and rapidity of V-I transmission matrix method are highlighted. 3. Aiming at two kinds of non-uniform fiber Bragg grating acousto-optic modulators, the V-I transmission matrix method is proposed to analyze the influence of the refractive index distribution caused by the ultrasonic frequency and the sonic strain amplitude on the reflectance spectrum. The relationship between the wavelength interval between the primary and secondary reflection peaks and the ultrasonic frequency, as well as the relationship between the reflectivity of the reflection peak and the amplitude of the acoustic strain are obtained. The longitudinal acoustic waves are generated by using the shear mode PZT. The chirped fiber Bragg grating (FBG) is modulated by ultrasonic wave with frequency 2MHz. The experimental results are consistent with the simulation results.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN761

【共引文献】