干涉型光纤陀螺仪的设计与制作(3)

干涉型光纤陀螺仪的设计与制作

目录

摘 要 .......................................................................................................................................... I 引 言 ......................................................................................................................................... 1 1 光纤陀螺 ............................................................................................................................... 2 1.1光纤陀螺的应用方面 .................................................................................................... 2 1.2干涉式光纤陀螺 ............................................................................................................ 2 1.3干涉式光纤陀螺的发展动向 ........................................................................................ 3 1.3.1光纤陀螺的小型技术 ............................................................................................ 3 1.3.2光纤陀螺的多路复用技术 .................................................................................... 3 2 干涉式光纤陀螺的原理 ....................................................................................................... 4 2.1 Sagnac效应 ................................................................................................................... 4 2.1.1真空中的Sagnac效应 ........................................................................................... 4 2.1.2介质中的Sagnac效应 ........................................................................................... 4 2.1.3任意形状的闭合回路 ............................................................................................ 5 2.2 Sagnac光纤干涉仪的互易性 ....................................................................................... 5 2.3干涉式光纤陀螺的主要指标 ........................................................................................ 6 2.4 干涉式光纤陀螺的各种误差源 ................................................................................... 6 3干涉式光纤陀螺的随机仿真 ................................................................................................ 7 3.1 Allan方差分析 .............................................................................................................. 7 3.2 Allan方差的噪声系数拟合 .......................................................................................... 8 3.3 建模与仿真 ................................................................................................................... 9 4 干涉式光纤陀螺光学部分方案 ......................................................................................... 12 4.1 I-FOG结构 ................................................................................................................... 12 4.2 光源 ............................................................................................................................. 12 4.2.1 1.55um宽带超荧光掺铒光纤光源（SFS） ....................................................... 12 4.2.2 超发光二极管（SLD） ....................................................................................... 13 4.3 光纤耦合器 ................................................................................................................. 13 4.3.1保偏光纤耦合器 .................................................................................................. 13

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4.3.2光学环形器 .......................................................................................................... 14 4.4 光纤线圈 ..................................................................................................................... 14 4.4.1 保偏光纤原理 ..................................................................................................... 14 4.4.2 保偏光纤优点 ..................................................................................................... 14 4.4.3 保偏光纤应力结构 ............................................................................................. 14 4.5 多功能集成光路 ......................................................................................................... 15 4.5.1 多功能集成光路结构 ......................................................................................... 15 4.5.2 多功能集成光路技术指标 ................................................................................. 16 4.5.3 多功能集成光路实物图与外观尺寸 ................................................................. 16 4.6 探测器 ......................................................................................................................... 16 4.7 波长控制方案 ............................................................................................................. 16 4.8 前置放大滤波器 ......................................................................................................... 17 4.8.1 前置放大器 ......................................................................................................... 17 4.8.2 低通滤波器 ......................................................................................................... 17 5干涉式光纤陀螺硬件部分方案 .......................................................................................... 19 5.1引言 .............................................................................................................................. 19 5.2 硬件部分方案 ............................................................................................................. 19 5.3 干涉型光纤陀螺仪的信号检测 ................................................................................. 19 5.4 A/D- D/A模块 ........................................................................................................... 20 5.5 信号处理模块 ............................................................................................................. 20 6 总结 ..................................................................................................................................... 22 7 致谢 ..................................................................................................................................... 23 8 参考文献 ............................................................................................................................. 24

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摘 要

本文介绍了光纤陀螺的特点、应用领域及技术发展动向，在Sagnac原理以及各种误差源的基础上，通过分析光纤陀螺的随机漂移特性对光纤陀螺精度的影响，运用Allan方差理论对光纤陀螺输出信号的随机误差进行定量分析，用一阶马尔科夫过程来模拟指数相关噪声，对光纤陀螺进行了随机建模和仿真。通过对干涉式光纤陀螺理论分析提出了光学上切实可行的方案，并进行了光源选取与驱动，保偏光纤、多功能集成光路及探测器的选择，波长控制的分析，信号的前置放大滤波电路的设计。

关键字： I-FOG Sagnac原理 Allan方差 随机建模 前置放大滤波

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ABSTRACT

The article describes the features, applications and technology developments of FOG, based on Sagnac principle and various error sources, through the analysis of the effects of random drift of FOG's accuracy, using Allan variance theory to FOG output signal of random error for quantitative analysis, using a first-order Markov process to simulate related noise, conducted a random modeling and simulation. Through theoretical analysis of interferometric fiber optic gyro optically proposed practical solutions, and select the source and drive, polarization maintaining fiber, multifunction integrated optics and detector, analysis wavelength control and design preamplifier filter circuit.

Keywords: I-FOG Sagnac principle Allan variance Stochastic Modeling Preamp filter

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干涉型光纤陀螺仪的设计与制作

引 言

光纤陀螺是用于测量惯性系统运载体的角速度，当惯性运载体旋转时，光纤陀螺仪利用Sagnac效应相移导致光波干涉条纹产生的微小移动，测得陀螺的旋转角速率，是当前精密物理测量技术，也是惯性系统里的重要部件。因为光纤陀螺具有调整结构的灵活性、总体质量轻、实体体积小、抗电磁干扰强于传统陀螺仪、动态范围大、灵敏度高等特点，被惯性系统得到广泛重视和应用。

本课题拟设计一个干涉式光纤陀螺仪,要求了解光纤陀螺的基本原理及Sagnac效应，对光纤陀螺的光学部分进行设计，要求进行仿真分析，通过对建模仿真分析提出光学上光纤陀螺的光学部分的方案，并进行光纤陀螺的光源选取与驱动，保偏光纤、多功能集成光路及探测器的选择，波长控制的分析，信号的前置放大滤波电路的设计。

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