【作者】 刘伟升；

【导师】 何赛灵；

【作者基本信息】 浙江大学 ， 光学工程， 2011， 博士

【摘要】 光纤光栅是一种重要的光纤型无源器件,它在光纤传感、微波光子学以及光纤通信技术等领域有着重要的应用,得到了广泛的研究和产业关注。本文针对光纤光栅在光纤传感领域的两个重要研究方向(光纤光栅传感器的设计制作以及传感信号的解调和复用)以及基于光纤光栅的DBR光纤激光器的应用技术进行了研究。本文首先简介了光纤光栅出现的研究背景；介绍了光纤光栅传感技术并对其研究热点进行了分析和说明；介绍了光纤光栅激光器的应用情况。接着介绍了光纤光栅的物理模型和基本理论工具(包括射线理论,耦合模理论和传输矩阵算法)；简介了几种主要的光纤光栅类型,并通过模拟计算分析了它们的光谱特性；介绍了几种常见的光纤光栅制作方法以及本论文中所使用的光纤光栅制作系统。然后设计并通过实验验证了两种基于光纤光栅复合结构的光纤光栅传感器：研究基于光纤布拉格光栅法布里-珀罗腔的高分辨率传感器,并通过一个扫频单纵模半导体激光器实现了其传感信号的低成本快速解调；研究了倾斜光纤光栅(TFBG)与长周期光纤光栅(LPG)之间的包层模耦合特性,并实现了基于LPG-TFBG复合结构的振动传感器。接下来提出了几种光纤布拉格光栅传感器的解调和复用技术：研究了基于低相干反射计的FBG传感器解调技术,分别通过不同拓扑结构实现了FBG传感器的复用,实现了基于结合低相干复用和空分复用的混合复用FBG多参量传感网络,并进行了甲烷浓度、温度、应力等多种参量的测量实验；提出了基于微波光子滤波器的FBG传感器解调与复用方案并进行了实验验证；研究了基于频谱受限的FDML光纤激光器的FBG传感器解调与复用系统的原理,并利用该系统实现了相同波长的低反射率FBG传感器的解调与复用,搭建了结合拉曼放大的频谱受限FDML光纤激光器,并将其用于长距离传感。最后在两种不同的光纤上制作出了短腔布拉格反射式(DBR)光纤激光器。其中在细芯掺铒光纤上制作的短腔DBR光纤激光器因具有很低的偏振拍频频率而适用于光纤传感,通过实验研究了其在水听器和高灵敏度弯曲传感器中的应用,并通过二次曝光技术实现了偏振拍频频率可调；在保偏掺铒光纤上制作的短腔DBR光纤激光器具有很高的偏振拍频频率而适用于高频微波源,实验中获得了频率高达46.66 GHz的高频微波信号,并通过频率上/下转换技术实现了高频微波信号的低频测量。更多还原

【Abstract】 Fiber gratings, as key passive fiber components, have received great research interest both academically and industrially because of their widely applications in fiber sensors, microwave photonics, and optical fiber communications, etc. This thesis mainly focuses on the study of fiber grating sensors and their interrogating and multiplexing technology, fiber Bragg grating based distributed Bragg reflector fiber lasers and their applications in sensing and microwave generation.Firstly, a brief overview of the background and evolution of fiber grating technology is given. Fiber grating sensing technology and recent research topics in this area are introduced. And the applications of fiber grating-based lasers are also summarized.Then, a brief introduction on the physical model and basic analysis tools of fiber gratings is given, including grating diffraction, coupled-mode theory and transfer matrix method. Several kinds fiber gratings in common use are introduced and their typical spectra are given with simulation results. The basic techniques for fiber gratings fabrication are summarized and the fabrication system used in this thesis is introduced.After that, two novel designs of fiber grating sensors are proposed and experimentally demonstrated. A fiber Bragg grating (FBG) Fabry-Perot based fiber sensor with ultrahigh resolution is studied and low cost interrogation with fast speed is achieved by employing a tunable single-longitudinal-mode semiconductor laser diode; then, the cladding modes recoupling between tilted FBGs (TFBGs) and long period gratings (LPGs) are investigated and a vibration sensor is achieved based on hybrid LPG-TFBG.Then, the interrogating and multiplexing techniques of FBG sensors are studied. Interrogating and multiplexing of FBG sensors with different topology based on optical low-coherent reflectometry is demonstrated. A multi-parameter FBG sensing network with over 40 FBG sensors is achieved by the combination of low-coherent multiplexing technique and spatial division multiplexing technique. And experiments on methane concentration, temperature and strain sensing are carried out with this sensing network. A microwave photonic filter based FBG sensing system is proposed, and its interrogating and multiplexing capability is studied experimentally. FBG sensors system based on a spectrum-limited Fourier domain mode-locking fiber laser is developed. Interrogating and multiplexing of low reflective FBG sensors with the same Bragg wavelengths is demonstrated with this system. And by incorporating a Raman amplifier, long distance sensing application is achieved.Finally, short cavity distributed Bragg reflector (DBR) fiber lasers are fabricated in two different types of erbium doped fibers. The DBR fiber lasers fabricated in a thin core erbium doped fiber have very low polarization beat frequency and thus they are suitable for sensing applications. Ultrasonic hydrophone and highly sensitive bending sensor based on this kind of fiber lasers are demonstrated experimentally. Tuning of the beat frequency is achieved by additional UV side-irradiating at the laser cavity. DBR fiber lasers fabricated in a polarization maintained erbium doped fiber have very high polarization beat frequency and thus can be used for high frequency microwave signal generation. A microwave with a high frequency of 46.66 GHz is generated experimentally, which is measured at a lower frequency through frequency up/down conversion technique.更多还原