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Optimizing Optical fiber Faults Detection:A Comparative Analysis of Advanced Machine Learning Approaches

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Computers, Materials & Continua 2024年第5期79卷 2697-2721页

作者： Kamlesh Kumar Soothar Yuanxiang Chen Arif Hussain Magsi Cong Hu Hussain Shah School of Electronics Engineering Beijing University of Posts and TelecommunicationsBeijing100876China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an710071China State Key Laboratory ofNetworking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China

Efficient optical network management poses significant importance in backhaul and access network communicationfor preventing service disruptions and ensuring Quality of Service(QoS)satisfaction.The emerging faultsin optical networks introduce challenges that can jeopardize the network with a variety of faults.The existingliterature witnessed various partial or inadequate solutions.On the other hand,Machine Learning(ML)hasrevolutionized as a promising technique for fault detection and prevention.Unlike traditional fault managementsystems,this research has three-fold contributions.First,this research leverages the ML and Deep Learning(DL)multi-classification system and evaluates their accuracy in detecting six distinct fault types,including fiber cut,fibereavesdropping,splicing,bad connector,bending,and PC connector.Secondly,this paper assesses the classificationdelay of each classification algorithm.Finally,this work proposes a fiber optics fault prevention algorithm thatdetermines to mitigate the faults accordingly.This work utilized a publicly available fiber optics dataset namedOTDR_Data and applied different ML classifiers,such as Gaussian Naive Bayes(GNB),Logistic Regression(LR),Support Vector Machine(SVM),K-Nearest Neighbor(KNN),Random Forest(RF),and Decision Tree(DT).Moreover,Ensemble Learning(EL)techniques are applied to evaluate the accuracy of various classifiers.In addition,this work evaluated the performance of DL-based Convolutional Neural Network and Long-Short Term Memory(CNN-LSTM)hybrid classifier.The findings reveal that the CNN-LSTM hybrid technique achieved the highestaccuracy of 99%with a delay of 360 s.On the other hand,EL techniques improved the accuracy in detecting fiberoptic faults.Thus,this research comprehensively assesses accuracy and delay metrics for various classifiers andproposes the most efficient attack detection system in fiber optics.

关键词： fiber optics fault detection multiclassification machine learning ensemble learning

Numerical Investigation Into a Surface Plasmon Resonance Sensor Based on Optical fiber Microring

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Photonic Sensors 2017年第2期7卷 105-112页

作者： Chunliu ZHAO Yanru WANG Dongning WANG Zhewen DING Institute of Optoelectronic Technology China Jiliang University Hangzhou 310018 China

A reflective surface plasmon resonance （SPR） sensor based on optical fiber microring is proposed. In such a sensor, plasmons on the outer surface of the metallized channels containing analyte can be excited by a fundamental mode of a thin-core fiber （TCF）. The refractive index （RI） sensing can be achieved as the surface plasmons are sensitive to changes in the refrective index of the analyte. Numerical simulation results show that the resonance spectrum shifts toward the shorter wavelength gradually when the analyte refractive index increases from 1.0 to 1.33, whereas it shifts toward the longer wavelength gradually when the analyte refractive index increases from 1.33 to 1.43, and there is a turning point at the refractive index value of 1.33. The highest sensitivity achieved is up to 2.30×10^3nm/RIU near the refractive index value of 1.0. Such a compact sensor has potential for gaseous substance monitoring.

关键词： fiber optics surface plasmons sensors microstructure

Ultra-small interferometric fiber optic gyroscope with an integrated optical chip

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Chinese optics Letters 2022年第4期20卷 1-5页

作者：尚克军雷明李豪伟张天其于晓之向强那永林张丽哲 State Key Laboratory of Inertial Technology Beijing Institute of Automatic Control EquipmentBeijing 100074China

This study proposes a novel interferometric fiber optic gyroscope(IFOG)based on an integrated optical chip,application-specific integrated circuit,and small-diameter sensing coil.The overall size and weight of the prototype are 30 mm × 30 mm ×30 mm and 68 g,respectively,making it the smallest closed-loop IFOG,to the best of our knowledge.A static experiment shows that the bias stability of the integrated IFOG is very close to the theoretical accuracy limit determined by the fiber coil and can satisfy the requirements of near-navigation-grade compact inertial navigation systems.

关键词： gyroscopes fiber optics fiber optics sensors integrated optics

fiber oscillator of 5 kW using fiber Bragg gratings inscribed by a visible femtosecond laser

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Chinese optics Letters 2023年第2期21卷 50-54页

作者：李宏业田鑫李昊武柏屹赵晓帆王蒙高晨晖饶斌裕奚小明陈子伦王泽锋陈金宝 College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China State Key Laboratory of Pulsed Power Laser Technology Changsha 410073China Hunan Provincial Key Laboratory of High Energy Laser Technology Changsha 410073China

We fabricate a pair of fiber Bragg gratings(FBGs)by a visible femtosecond laser phase mask scanning technique on passive large-mode-area double-cladding fibers for multi-kilowatt fiber oscillators.The bandwidth of high-reflection(HR)and lowreflection(LR)FBG is~1.6 nm and 0.3 nm,respectively.The reflection of the HR-FBG is higher than 99%,and that of the LR-FBG is about 10%.A bidirectional pumped all-fiber oscillator is constructed using this pair of FBGs,a record output power of 5027 W located in the signal core is achieved with a slope efficiency of~82.1%,and the beam quality factor M2is measured to be~1.6 at the maximum power.The FBGs are simply fixed on a water cooling plate without a special package,and the thermal efficiency of the HR-FBG and the LR-FBG is 2.76℃/kW and 1℃/kW,respectively.Our research provides an effective solution for robust high-power all-fiber laser oscillators.

关键词： fiber optics fiber lasers fiber Bragg gratings

Mode field diameter and nonlinear properties of air-core nanowires

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Chinese Physics B 2009年第8期18卷 3183-3188页

作者：胡晓鸿赵卫宫永康王擂然卢克清刘雪明 State Key Laboratory of Transient optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

Exact solutions of Maxwell＇s equations describing the lightwave through 3-layer-structured cylindrical waveguide are obtained and the mode field diameter and nonlinear coefficient of air-core nanowires （ACNWs） are numerically calculated. The simulation results show that ACNWs offer some unique optical properties, such as tight field confining ability and extremely high nonlinearity. At a certain wavelength and air core radius, we optimize the waveguide design to maximize the nonlinear coefficient and minimize the mode field diameter. Our results show that the ACNWs may be powerful potential tools for novel micro-photonic devices in the near future.

关键词： waveguides nanowires numerical calculation fiber optics

ANSYS-Based Birefringence Property Analysis of Side-Hole fiber Induced by Pressure and Temperature

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Photonic Sensors 2018年第1期8卷 13-21页

作者： Xinbang ZHOU Zhenfeng GONG School of Ocean Science and Technology Dalian University of Technology. Panjin Panjin 124000 China College of Physics and Optoelectronics Engineering Dalian University of Technology Dalian 116024 China

在这份报纸，我们理论上用有限元素分析方法与洞的不同形状在方面洞纤维的 birefringence 性质上调查压力和温度的影响。方面洞纤维的 birefringence 的物理机制与不同外部压力和温度的存在被讨论。圆形核心、矩形核心、三角形核心的方... 详细信息

在这份报纸，我们理论上用有限元素分析方法与洞的不同形状在方面洞纤维的 birefringence 性质上调查压力和温度的影响。方面洞纤维的 birefringence 的物理机制与不同外部压力和温度的存在被讨论。圆形核心、矩形核心、三角形核心的方面洞纤维的紧张领域分发和 birefringence 价值被介绍。我们的分析证明三角形核心的方面洞纤维有削弱温度和紧张的生气敏感的低温度敏感。另外，方面洞纤维的一个优化结构图案被介绍它能被用于察觉到的申请。

关键词： fiber optics birefringence pressure measurement temperature

Research of Optical fiber Coil Winding Model Based on Large-deformation Theory of Elasticity and Its Application

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Chinese Journal of Aeronautics 2011年第5期24卷 640-647页

作者： JIA Ming YANG Gongliu School of Instrumentation Science and Opto-electronics Engineering Beihang University Beijing 100191 China

Optical fiber coil winding model is used to guide proper and high precision coil winding for fiber optic gyroscope （FOG） application. Based on the large-deformation theory of elasticity, stress analysis of optical fiber free end has been made and balance equation of infinitesimal fiber is deduced, then deformation equation is derived by substituting terminal conditions. On condition that only axial tensile force exists, approximate curve equation has been built in small angle deformation scope. The comparison of tangent point longitudinal coordinate result between theory and approximation gives constant of integration, and expression with tangent point as origin of coordinate is readjusted. Analyzing the winding parameters of an example, it is clear that the horizontal distance from the highest point of wheel to fiber tangent point has millimeter order of magnitude and significant difference with fiber tension variation, and maintains invariant when wheel radius changes. The height of tension and accurate position of tangent point are defined for proper fiber guide. For application to fiber optic gyroscope, spiral-disc winding method and nonideal deformation of straddle section are analyzed, and then spiral-disc quadrupole pattern winding method has been introduced and realized by winding system. The winding results approve that the winding model is applicable.

关键词： fibers fiber optics large-deformation fiber optic gyroscope spiral-disc winding quadrupole pattern

Hybrid algorithm combining genetic algorithm with back propagation neural network for extracting the characteristics of multi-peak Brillouin scattering spectrum

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Frontiers of Optoelectronics 2017年第1期10卷 62-69页

作者： Yanjun ZHANG Jinrui XU Xinghu FU Jinjun LIU Yongsheng TIAN The Key Laboratory for Special fiber and fiber Sensor of Hebei Province School of Information Science and Engineering Yanshan University Qinhuangdao 066004 China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Key Laboratory of Advanced Forging & Stamping Technology and Science College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China

In this study, a hybrid algorithm combining genetic algorithm （GA） with back propagation （BP） neural network （GA-BP） was proposed for extracting the characteristics of multi-peak Brillouin scattering spectrum. Simulations and experimental results show that the GA-BP hybrid algorithm can accurately identify the position and amount of peaks in multi-peak Brillouin scattering spectrum. Moreover, the proposed algorithm obtains a fitting degree of 0.9923 and a mean square error of 0.0094. Therefore, the GA-BP hybrid algorithm possesses a good fitting precision and is suitable for extracting the characteristics of multi-peak Brillouin scattering spectrum.

关键词： fiber optics Brillouin scattering spectrum,genetic algorithm （GA） back propagation （BP） neural network multi-peak spectrum

Generation of a large orbital angular momentum beam via an optical fiber winding around a curved path and its application

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Chinese Physics B 2021年第10期30卷 342-350页

作者：谭维翰赵超樱孟义朝郭奇志 Department of Physics Shanghai UniversityShanghai 200444China College of Science Hangzhou Dianzi UniversityHangzhou 310018China State Key Laboratory of Quantum optics and Quantum optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Institute of fiber optics Shanghai UniversityShanghai 200444China

Many papers have been published on the study of orbital angular momentum(OAM)of the laser modes based on the Laguerre-Gaussian(LG)beam and helical phase plate or rotating cylindrical lens,and the principal ray of the LG beam remains straight line.These ways are difficult to get a large OAM modes.In this paper,we propose a novel method to prepare a large OAM modes when the light propagates through a optical fiber winding around a curved path,and establish a theoretical framework based on the principal ray path changing.Firstly,we investigate three kinds of winding structure.Secondly,based on the analytical solutions and numerical calculations,we can find that the spiral body can achieve a large OAM temporal pulse.At the same time,based on the zero OAM diffraction diagram,we can obtain an improvement of resolving power beyond Rayleigh’s criterion.Finally,applying a large OAM diffraction pattern to realize 12-bitencodes,we can obtain a high-security optical information transfer system.

关键词： fiber optics orbital angular momentum(OAM) differential Fernet equation Rayleigh criterion