Curvature Sensor Based on a Long-Period Grating in a Fiber Ring Resonator Interrogated by an OTDR  

作　　者：Regina MAGALHAES Susana SILVA Orlando FRAZAO 

机构地区：[1]INESC TEC and Department of Physics and Astronomy,Faculty of Sciences of University of Porto,Porto 4169-007,Portugal

出　　处：《Photonic Sensors》2020年第1期1-6,共6页光子传感器（英文版）

基　　金：This work is financed by National Funds through the Portuguese funding agency,FCT-“Fundação para a Ciência e a Tecnologia”under Grant No.UID/EEA/50014/2019.

摘　　要：The proposed technique demonstrates a fiber ring resonator interrogated by an optical time domain reflectometer(OTDR),for intensity sensing.By using this methodology,a cavity round trip time of 2.85ms was obtained.For a proof of concept,a long-period grating was inserted in the resonant cavity operating as a curvature sensing device.A novel signal processing approach was outlined,regarding to the logarithmic behavior of the OTDR.Through analyzing the experimental results,an increase in the measured sensitivities was obtained by increasing applied bending.With curvatures performed from 1.8 m^(-1) to 4.5 m^(-1),the sensitivity values ranged from 2.94 dB·km^(-1) to 5.15 dB·km^(-1).In its turn,the sensitivities obtained presented a linear behavior when studied as a function of the applied curvature,following a slope of 0.86×10-3 dB.The advantages of applying this technique were also discussed,demonstrating two similar fiber rings multiplexed in a series of configurations.

关 键 词：Cavity ring-down CURVATURE fiber ring resonator long period grating optical fiber sensors OTDR 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]