SENSORS: The Exploration of Novel All-Purpose All-fiber Spectrometer Module for Scalable and Distributed Optical Fiber Sensor System

传感器：用于可扩展分布式光纤传感器系统的新型通用全光纤光谱仪模块的探索

• 批准号: 0330496
• 负责人: Henry Lee
• 金额: $ 50万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0330496&HistoricalAwards=false
• 关键词: SENSORS; Exploration; Novel; Purpose; fiber

Fiber-optic sensors have become one of the most important sensors for structural monitoring. Inparticular, Fiber Bragg Grating (FBG) based sensors used in conjunction with a wavelengthdivision multiplexing (WDM) scheme, where each FBG sensor is dedicated to a sensor channelwhile sharing a common fiber link and interrogation module, have emerged as the most attractiveapproach for implementing large-scale civil engineering monitoring systems. The strength of theFBG sensor lies in its all-fiber nature. It can be easily connected to the interrogation module by afiber link thus bypassing the labor-intensive packaging bottleneck. However, a major obstaclefacing FBG-based sensor technology in field deployment is the lack of a cost-effectiveinterrogation module capable of handling multiple FBG sensors.Here we propose a novel all-fiber spectrometer as the building block for a low-cost interrogationmodule. The proposed all-fiber spectrometer consists of an Acousto-Optic Tunable Filter (AOTF)implemented directly on a 10-30 cm long single-mode fiber and an on-fiber semiconductorphotodetector. The spectrometer is built on our prior research experience in tunable all-fiberdevices for dense WDM fiber-optic communication applications. It combines the merits of an all-fiberdevice and the wide tunability of an AOTF. The all-fiber spectrometer is compact, lightweight, fast, low cost and has a performance comparable to existing grating-based and Fabry-Perotspectrometers. In addition, its non-blocking characteristics enables a distributedinterrogation architecture that offers scalability, interchangeability, and enhanced systemredundancy. Although the primary application of this proposal is on structural sensing, the all-fiberspectrometer can be developed as a hand held portable sensor system for chemical andbiochemical applications.The basic operating principle of our approach has been demonstrated in the laboratory. Using afrequency-shift key (FSK) modulation scheme, we have demonstrated wavelength accuracy of0.02 nm (this corresponds to a strain of 20 ustrain) for a sensor channel spacing of 1.2 nm withroom for additional performance improvement. With further reduction of the filter bandwidth,improvement of the packaging design, particularly thermally stability, we aim at developing aprototype multi-section AOTF spectrometer to be field tested in actual civil engineeringstructures to demonstrate the practicality of this new approach.The project team reflects a multi-disciplinary effort. Dr. H. P. Lee, the PI, is leading a group witha proven research record in tunable all-fiber devices. Dr. M. Feng has a distinguished researchrecord in exploring various sensors for health monitoring of civil engineering structures. Dr. F.G.Shi brings in much needed expertise in packaging design, simulation, and reliability modeling.The research infrastructure is already in place at the PI's home institution, and the CaliforniaDepartment of Transportation will provide in-kind support for field trials on its highways andbridges.The proposed projects are expected to have strong impact on research, education, and potentialtechnology transfer. As reflected from the budget, the project is leaning heavily on supportinggraduate students. Based on our experience at UC Irvine, we also expect active participation ofundergraduate students through the campus-sponsored UROP (undergraduate researchopportunity program) to work with the graduate students and faculty.

光纤传感器已成为结构监测中最重要的传感器之一。特别是，基于光纤布拉格光栅（FBG）的传感器与波分复用（WDM）方案结合使用，其中每个FBG传感器专用于一个传感器通道，同时共享一个共同的光纤链路和询问模块，已成为实施大规模土木工程监测系统的最有吸引力的方法。FBG传感器的优势在于其全光纤特性。它可以很容易地通过光纤连接到询问模块，从而绕过劳动密集型包装瓶颈。然而，一个主要的障碍，面对基于FBG的传感器技术在现场部署是缺乏一个具有成本效益的询问模块能够处理多个FBG传感器。在这里，我们提出了一种新的全光纤光谱仪作为构建块的低成本询问模块。提出的全光纤光谱仪包括一个声光可调谐滤波器（AOTF）直接实现在一个10-30厘米长的单模光纤和一个光纤上的光电探测器。光谱仪是建立在我们以前的研究经验，在可调谐全光纤密集波分复用光纤通信应用的设备。它结合了全光纤器件的优点和AOTF的宽调谐性。该全光纤光谱仪结构紧凑、重量轻、速度快、成本低，其性能可与现有的光栅光谱仪和法布里-珀罗光谱仪相媲美。此外，其非阻塞特性使分布式询问架构能够提供可扩展性、可扩展性和增强的系统冗余。虽然该方案的主要应用是结构传感，但全光纤光谱仪可以发展为手持式便携式传感器系统，用于化学和生物化学应用。使用移频键控（FSK）调制方案，我们已经证明了0.02 nm的波长精度（这对应于20 μ应变）的传感器通道间距为1.2 nm的额外的性能改进的空间。随着滤波器带宽的进一步降低，封装设计的改进，特别是热稳定性，我们的目标是开发一个原型的多节AOTF光谱仪在实际的土木工程结构进行现场测试，以证明这种新方法的实用性。H博士P. Lee，PI，领导着一个在可调谐全光纤设备方面有着良好研究记录的小组。M博士冯在探索各种传感器用于土木工程结构健康监测方面有着杰出的研究记录。F.G.Shi博士带来了包装设计、模拟和可靠性建模方面急需的专业知识。PI所在机构的研究基础设施已经到位，加州交通部将为公路和桥梁的现场试验提供实物支持。拟议的项目预计将对研究、教育和潜在的技术转让产生重大影响。正如预算所反映的那样，该项目严重依赖于对研究生的支持。根据我们在加州大学欧文分校的经验，我们还希望通过校园赞助的UROP（本科生研究机会计划）与研究生和教师一起积极参与研究生。