Fiber optic distributed sensing techniques with high spatial resolution and high performance for smart materials, structures and communication networks.

该项目原计划的研究课题已经做了足够的工作，还增加了一些新的课题并进行了表演。对于第一个课题“基于光纤局部产生的受激布里渊散射的光纤分布式应变传感技术”，引入了动态应变传感功能。获得的采样率为57赫兹，比传统的时域技术快1万倍。在建筑物模型振动测量中，首次实现了多点同时动态应变传感。利用这种技术的厘米级空间分辨率，还首次测量了亚毫米宽度的混凝土中的裂缝。这是唯一一种可以测量厘米级空间分辨率和几十赫兹采样率的光纤分布应变的技术。这些功能正在为材料和结构创建新的诊断算法。一种简化系统的方法，方案…此外，为了扩大测量范围，还提出了同时测量应变和温度的方法，以及实现较高空间分辨率的方案并进行了实验。在第二个课题“基于光学相干函数合成的光纤分布侧向应力测量”中，空间分辨率提高了约40倍，达到20 cm。还实现了一个简化的系统。至于第三个课题“光纤到家庭网络的诊断系统”，测量范围得到了改进。在长度为5 km的光纤末端，测量了反射率分布，空间分辨率约为10 cm，测量范围约为1 km。关于第四个课题“相关传感技术”，最近利用光学相干函数合成技术(SOCF)开发了一种用于多路复用具有相同布拉格波长的FBG的系统。实现了100赫兹的采样率和随机接入能力。提出并研制了基于多波长光纤激光器的FBG多路复用系统、基于SOCF的EDF动态光栅特性控制方案、光纤振动分布测量系统等。通过这项研究项目，成功地开发了用于智能材料、结构和通信网络的光纤神经系统的新技术。较少

Research subjects originally scheduled in this project have enough been done, and some new subjects have also been added and performed. As for the first subject "Fiber optic distributed strain sensing technique by use of stimulated Brillouin scattering generated locally along the fiber," dynamic strain sensing function has been introduced. The sampling rate obtained is 57Hz, which is 10,000 time faster than conventional time domain technologies. In vibration measurement using a building model, multiple points, simultaneous and dynamic strain sensing has been done for the first time. Clack in concrete with sub-mm width has also been measured for the first time, utilizing cm-order spatial resolution of this technique. This technique is only one that can measure distributed strain along a fiber with cm-order spatial resolution and several tens of Hz sampling-rate. These functions are creating new diagnostic algorithm for materials and structures. A way for simplifying the system, a scheme … More for elongating the measurement range, a way for measuring simultaneously strain and temperature, and a scheme for realizing quite a high spatial resolution have also been proposed and experimented. As for the second subject "Fiber optic distributed lateral stress measurement by synthesis of optical coherence function," the spatial resolution has been improved as about 40 times to be 20cm. A simplified system has also been realized. As for the third subject "Diagnostic system for fiber to the home networks," measurement range has been improved. At the end of 5km length fiber, reflectivity distribution has been measured with about 10cm spatial resolution and 1km measurement range. As for the forth subject "Related sensing technologies," a system for multiplexing FBG's with the same Bragg wavelength has newly been developed by the use of synthesis of optical coherence function technique (SOCF). Sampling rate of 100Hz and random access capability has been realized. A FBG multiplexing system using a fiber laser with multiple lasing wavelengths, scheme for controlling characteristics of EDF dynamic grating by SOCF, a system for measuring vibration distribution along a fiber, and so on, have also been proposed and developed. Through this research project, novel techniques of fiber optic nerve systems for smart materials, structures and communication networks have been successfully developed. Less