Research On Novel Fiber Sensing Technologies Of Index, Temperature And Fiber Fault Location

The optical fiber sensor is an important research direction of sensor, it has manyadvantages, such as simple, light, shaping easily, thermostability, corrosion-resisting,immunizing to the electromagnetic interference etc., and it has been widely used in variousfields. The development directions of modern fiber sensor are intelligent, miniature andhighly sensitive etc., these characteristics mean that the optical fiber sensor will be morewidely used in the future.According to the main job, the paper makes a deep analysis on the research backgroundand situation of the optical fiber sensing technology. The paper will expound the study resultby different research fields with three parts,(1) first of all, proofing that the main loss of the load-hydrogen fiber is the optical fibercore micro bending loss, and putting forward a kind of simple fiber index sensing technologybased on the splicing bubble.(2) Secondly, according to a characteristic of the optical fiber Bragg grating F-P combfilter (FBG-FPF), which is that the free spectral range of the FBG-FPF is changed, we putforward a new sensing demodulation method, which is based on the double wavelength laserbeating frequency technology, and realize a fiber temperature sensor in a certain temperaturerange.(3) Finally, proposing a kind of chaotic light source based on a SOA ring without filter,isolator, which reduces the system’s complexity and cost, and the output chaotic signal has agood performance. Using the chaotic light source based on the SOA ring cavity and thecorrelation analysis technology, we put forward a kind of high stability, high precisionchaotic OTDR, the spatial resolution of the COTDR is50μ m, and the time stability is+150μ m.