Study On A Core-offset Fiber Temperature Sensor Reseach Based On Labview

Compared to traditional sensors,optical fiber sensors have attracted enormous attention to scholars because of their small volume,light in weight,strong immunity to electromagnetic interference,and convenient remote sensing,etc.They are mainly applied to fields such as petroleum,electric power,health care and aerospace.So far there are as many as seventy physical quantities can be gauged by optical fiber sensors.As the technology of optical fiber sensor evolves,the current research directions of the experts focus on multi-parameter measurement sensor system design,new sensor structure research and improving sensor performance.This article mainly studies Two temperature sensor systems based on core-offset single mode fiber(SMF)and Mach–Zehnder interferometer(MZI).Rounded these capabilities about the sensibility and the measuring accuracy of the sensor system that will be discussed in practical application,we dive deeply into the temperature sensor systems.The innovation of this paper can be summarized as follows: 1)FRM is used into the spectrum temperature system.The temperature sensitivity in the SMF and FRM sensor is increased by an order of magnitude in comparison with the common sensors.The instability and low sensitivity characteristics of the commonly optical fiber sensor can be solved through the use of core-offset SMF and FRM.2)The system mainly uses the fiber loop ring-down technology to measure the temperature by electrical signal instead of by optical signal.Spectrometer could be out of use,and the succedaneum is photodetector and oscilloscope.It means that this method successfully reduce the cost and volume of the system.3)The efficiency of data processing is improved by using Labview,and we design three algorithms to analyze experiment figures to analysis data.Firstly,this paper introduces the technology of modular interference as well as technical background and development of the optical fiber sensor in details.Based on this theory we propose a kind of optical fiber sensor which contains the technology of MZI and core-offset SMF,and explain theoretically its core-offset structure and sensor theory.The advantage of this sensor is that it is fabricated by splicing in a section of SMF between two SMFs with a core-offset at two splicing joints.A part of light in the core is coupled in the fiber cladding.We can calculate the temperature by demodulating the interference signal.Due to the reason that the refractive index of cladding and core is different according to its sensibility,there will be a difference in the optical path in the transmission process,which results in the wavelength shift.So the core-offset fiber could be used to measure temperature by utilizing the phase difference between the core and cladding modes.Then we explain the making process of SMF fiber and confirm its parameter by comparison in experiment.Both these steps contribute to the theoretical parameters and experimental basis.Then,a highly sensitive temperature sensor system based on a Faraday rotation mirror(FRM)has been proposed and experimentally demonstrated in this paper.The variation of the transmission spectrum of the sensor with respect to the surrounding temperature has been experimentally studied.The experiment results show that,within the range of 1539.42 nm to 1553.90 nm,the sensitivity of the proposed sensor is 0.89039 nm/? and in the range of 47?-63?.Additionally,the power attenuation is 2.257dB/?.Finally,in order to solve the problems that a difficult demodulation of the optical fiber interferometry or a highly requirement for stability and so on,we present a fiber loop ring-down temperature system with the core-offset fiber.When the attenuation coefficient of loop ring-down is fixed,the output is characterized by exponential decay.Making user of this character,we can put core-offset into the loop ring-down.We can analyze the ring-down signal,and then calculate current temperature.Through Labview is used to process experimental data.This paper introduces the background and advantages of the technology.We design three algorithms to analyze experiment figures by using Labview.The experiment result proves the linear relationship between temperature and ring-down time,and compares the advantage of these algorithms.It successfully achieve the anticipated goal.