High Speed Distributed Optical Fiber Sensing

该奖项的研究目标是探索光纤中色散引起的信号群延迟及其在大跨度、高速分布式光纤传感中的应用。该方法将在一根光纤中复用大量相同的弱反射光纤布拉格光栅，并用快速的光谱-时间转换方法对它们进行询问。 这种对延迟时间测量的动态频谱表征规避了当前分布式光纤传感器产品中遇到的重平均和动态频谱分析的要求。系统中使用的超弱光栅的热稳定性将被研究，以改善其在高温下的性能。如果成功，这项研究的好处将包括许多民用和工业结构和系统的动态健康监测以及低成本的地震石油和天然气勘探。 这项技术也可能对地震探测和火山活动监测有用。 该研究的多学科性质将为参与的学生提供均衡的培训，丰富弗吉尼亚理工大学目前的光子学课程，并促进来自代表性不足的少数群体的学生参与科学和工程研究。

The research objective of this award is to explore the signal group delay induced by chromatic dispersion in optical fibers and its application in long-span, high speed distributed fiber optic sensing. The approach will be to multiplex a large number of identical weak reflecting fiber Bragg gratings in a single optical fiber and to interrogate them with a fast spectrum-to-time conversion method. This dynamic spectrum characterization to a delay-time measurement circumvents the requirements of heavy averaging and dynamic spectral analysis as encountered in the current distributed fiber sensor products. The thermal stability of the ultra-weak gratings used in the system will be investigated for their improved performance at high temperatures. If successful, the benefits of this research will include dynamic health monitoring of many civil and industrial structures and systems and low cost seismological oil and gas exploration. This technology may also be useful to earth quake detection and volcano activity monitoring. The multidisciplinary nature of the research will offer balanced training for the participating students, enrich the current photonics curriculum at Virginia Tech and promote the involvement of students from underrepresented minority groups in the scientific and engineering research.