新型光纤光栅传感复用系统的研究

【作者】 高宏伟；

【导师】 袁树忠； 开桂云；

【作者基本信息】 南开大学 ， 光学， 2006， 博士

【摘要】 光纤光栅是一种新型的光子器件,它是通过在光纤中建立起一种空间周期性的折射率分布,来改变和控制光在光纤中的传播行为。它也是近几年发展最为迅速的光纤无源器件之一。光纤光栅与光纤之间存在天然的兼容性,它不仅具有易与光纤连接、低损耗、光谱特性好、可靠性高等特点,而且作为传感元件,它具有其它传感器无可比拟的优点,即感应的信息用波长编码,而波长这个绝对参量不受光源功率的波动、连接或耦合损耗的影响。另外,光纤光栅传感还可以通过复用构成传感网络,即在一根光纤中可以连续写入或串接多个光纤光栅构成光纤光栅传感阵列,这是光纤光栅传感器独有的技术,也是降低光纤光栅传感系统成本,实现多点、分布式传感的重要途径。因此,光纤光栅传感器的复用技术引起了世界各国有关研究者的广泛关注和极大的兴趣。本论文以光纤光栅为研究对象,对其传感技术和解调技术进行了探讨,并着重分析研究了光纤光栅传感的复用技术。主要内容和创新点有:1.概括介绍了光纤光栅传感技术和光纤光栅传感复用技术的发展及现状。介绍了PETRI NET理论和排队论的原理,并分析了传统空分/波分光纤光栅传感复用技术的不足。2.提出基于高双折射光纤环镜和F-P滤波器的智能化光纤光栅传感复用系统,该系统只对波长变化的传感通路进行扫描解调,并可根据各传感通路的优先权、信息等待时间和和信号变化大小等综合设定扫描解调顺序。3.提出基于InGaAs阵列和F-P滤波器的智能化复用系统,该系统只对感测到被测量变化的传感器进行扫描解调,并可根据每一个传感器的优先权、信息等待时间和信号变化大小等灵活设定扫描解调顺序,平均解调速度也得到提高。4.首次提出了光纤光栅传感“信息采集参数”的概念,通过将优先权、信息等待时间和和信号变化大小等信息综合到“信息采集参数”的概念中来,使得光纤光栅传感复用系统可根据信息采集参数灵活设定信息采集次序。5.提出了具有远程监控功能的光纤光栅传感复用系统,该系统不仅可以通过光纤光栅感测被测量变化,而且可以根据感测到的传感信息通过光纤控制通更多还原

【Abstract】 Fiber gratings are new type of passive optical components, which are based on the periodical distribution of refraction index in fiber core. They are one type of developing fast passive fiber devices in recent years. Fiber gratings have several distinguished advantages, such as compare with fiber, low loss and high responsibility. As sensing element, they encode the sensing information in a wavelength form, which are their distinguished advantages over other transducers. That not only make the sensing information does not depend on loss of the system or fluctuation of then source power but also decrease the cost of sensing system and realize multipoint and distributed sensing. Therefore, lots of researchers are interested in fiber grating sensing multiplex techniques.In this dissertation, we mainly focus on the research and realization of fiber Bragg grating networks, including the principles and experiments of sensing and demodulation techniques. The contents are listed as follows:1. Generally introduce the sensing technique, especially the present situation and development of fiber grating sensing technique and fiber Bragg grating sensor multiplexing technique. The basic principle of PETRI NET theory and queue theory can be found in this dissertation. Then, we analyze the disadvantage of the combination of wavelength- and spatial-division multiplexing technique.2. A novel fiber Bragg grating sensors multiplexing system which combined with HiBi FLM and F-P filter is put forwarded. The experiment and the theory analysis demonstrated that the system only scan and demodulate sensing channels, whose wavelength is shifting. What’s more, the smart FBG sensors multiplexing system can rule the demodulate sequence by the priority, the waiting time and the wavelength shifting of every sensing channels. Therefore, the smart FBG sensors multiplexing system is more rational and smarter than the conventional counterpart.3. A novel multiplexing system which combined with InGaAs array and F-P filter is raised, analyze the disadvantage of the FBG multiplex technique which combined更多还原