A5071123255- Advanced Fiber Optic Sensors
- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Quantum Information and Cryptography
- Advanced Measurement and Metrology Techniques
- Speech and Audio Processing
- Quantum Computing Algorithms and Architecture
- Optical Coherence Tomography Applications
- Image and Signal Denoising Methods
- Optical measurement and interference techniques
- Advanced Photonic Communication Systems
- Blind Source Separation Techniques
- Chaos-based Image/Signal Encryption
- Advanced Sensor and Control Systems
- Semiconductor Lasers and Optical Devices
- Advanced Algorithms and Applications
- Geophysics and Sensor Technology
- Terahertz technology and applications
- Quantum Mechanics and Applications
- Neural Networks and Reservoir Computing
- Indoor and Outdoor Localization Technologies
- Optical Systems and Laser Technology
- Orbital Angular Momentum in Optics
Fudan University
2015-2025
Shanghai University
2022
It is crucial in a wide range of applications based on optical fiber interference to precisely measure the length difference interferometers. In this article, method measuring absolute between two arms interferometer system phase modulation light source proposed. This enables accurate measurement differences and suitable for both short-distance long-distance systems. Only an additional modulator needs be added realize measurement, making it easily implementable compensating in-service interferometer.
A novel distributed fiber-optic sensor is proposed and demonstrated, in which two Mach-Zehnder interferometers are used to detect the interference signals with different wavelengths, one 3 × coupler deployed demodulate time-varying phase change caused by vibration. The dual interferometer (DMZI) composed of wavelength division multiplexers. Then, a time delay estimation algorithm designed construct related using difference, constructed obtain vibration position through cross-correlation....
A novel distributed fiber-optic localization algorithm with high sensitivity and precision based on merged Michelson-Sagnac interferometer is proposed demonstrated. By performing simple addition subtraction processing the two phase differences of interferometers, superimposed signals a fixed delay can be obtained. The time calculated by cross-correlation algorithm. Combined polynomial fitting interpolation, disturbance location resolution significantly improved. total sensing distance reach...
In this paper, the Sagnac interferometer with a one-way optical fiber ring and novel dual distributed vibration sensor an asymmetrical structure for disturbance localization is proposed. The two interferometers in system are equal lengths of paths. Using time delay estimation based on cross-correlation, can be calculated from demodulated phase signals. precision ±10 m 50 km sensing overall error 0.02%. problem possibly existing systems firstly studied. Due to design path lengths, does not...
A dual-model hybrid pattern recognition based on a fiber optic line-based sensor with large amount of data is proposed. The vibration signals are converted to gray-level images reduce the memory requirement. ResNet18 model for classification used. To false positive rate, over-zero rate and short-time energy extracted from intrusion signal, support vector machine (SVM) Finally, discriminator constructed determine types events by combining two models trained validation dataset. results...
Signal recognition accuracy and time are the two most important parameters of pattern in a fiber optic vibration sensing system. To obtain high short time, this paper optimized VGG16 algorithm carried out VGG16-1D VGG16-2D on big data signals generated by Michelson–Sagnac interferometric sensor The results indicate that has higher 98.44% shorter 0.03 s. proposed method is more accurate faster for from optical systems, which helpful promoting further applications systems.
Optical fiber interferometer could achieve various dynamic measurements by transforming phase change into intensity change. In this paper, a novel Michelson (MI) based on two polarization beam splitters (PBSs) is proposed. Two thirds of Rayleigh backscattering (RB) separated from the signal light using PBS and Faraday rotating mirror (FRM) due to difference properties between RB in optical fibers. And signal-to-noise ratio (SNR) system has been significantly improved. Within detection range...
In this paper, a secure key generation and distribution scheme based on the phase noise of an amplified spontaneous emission source is proposed experimentally verified. A giant generator that contains two arms used to generate specific beat dependent path length difference arms. Through method balanced subtraction local signals, effect intensity has been mainly excluded, legal users obtain consistent differential signal depended noise. Experiment results show correlation coefficient signals...
We propose a practical secure key generation and distribution (SKGD) scheme for actual application. Based on the experiment results of polarization properties optical-fiber link, we SKGD method by active modulation state two scramblers placed at local end legal users in point-to-point communication system. Experiment prove that signals received share high correlation using 20 km standard single-mode fiber 1 KHz scrambling rate, bit rate can reach to 1216 bit/s with error <mml:math...
A scheme based on bidirectional Michelson interferometers to distribute secret keys through the phase of light wave is proposed and demonstrated. The structure uses two optical cable transmission schemes, lasers short coherent length, random drift, polarization disturbance, vibration positioning technology ensure safe key. feasibility 80 km key verified by experiments. When transmitted at frequency 200 kHz, bit error rate less than 0.3%, disturbance accuracy within <mml:math...
We theoretically and experimentally demonstrate a method for measuring the phase intensity noise their correlation in superluminescent diodes. A Michelson interferometer containing strongly unbalanced paths has been developed to measure noise. By spectral analysis of photocurrents detectors, is about twice value diode. The more interesting result we obtained experimental evidence that are mutually independent. coefficient fluctuates between −0.08 0, which shows scarcely any sign...
Distributed fiber vibration sensing system is widely used in the field of wide area security, communication cable long distances and pipeline security. The principle that for a signal applied at particular position along fiber, response, frequency domain, presents series periodic maxima minima (or nulls). These depend on fiber. Power spectral estimation method considered to denoise power spectrum determine these precisely paper. parametric modelling methods such as autoregressive-moving...
Optical fiber sensing is a novel technology with the advantages of anti-electromagnetic interference, anti-corrosion and high sensitivity suiting for many special applications. In this paper, Michelson optical voice monitoring system introduced sound extraction algorithm proposed to improve noise stability it. The demodulated by traditional based on <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3\times...
We propose a novel one-way ring optical fiber Sagnac system for voice sensing. The can realize real-time speech-to-text speech recognition using an open-source neural network model.