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Rapid extraction of the phase shift of the cold-atom interferometer via phase demodulation
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作者 程冰 王兆英 +2 位作者 许翱鹏 王启宇 林强 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期250-254,共5页
Generally, the phase of the cold-atom interferometer is extracted from the atomic interference fringe, which can be obtained by scanning the chirp rate of the Raman lasers at a given interrogation time T. If mapping t... Generally, the phase of the cold-atom interferometer is extracted from the atomic interference fringe, which can be obtained by scanning the chirp rate of the Raman lasers at a given interrogation time T. If mapping the phase shift for each T with a series of measurements, the extraction time is limited by the protocol of each T measurement, and therefore increases dramatically when doing fine mapping with a small step of T. Here we present a new method for rapid extraction of the phase shift via phase demodulation. By using this method, the systematic shifts can be mapped though the whole interference area. This method enables quick diagnostics of the potential cause of the phase shift in specific time. We demonstrate experimentally that this method is effective for the evaluation of the systematic errors of the cold atomic gravimeter. The systematic phase error induced by the quadratic Zeeman effect in the free-falling region is extracted by this method. The measured results correspond well with the theoretic prediction and also agree with the results obtained by the fringe fitting method for each T. 展开更多
关键词 atom interferometer phase extraction phase demodulation
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Advances in phase-sensitive optical time-domain reflectometry 被引量:9
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作者 Shuaiqi Liu Feihong Yu +3 位作者 Rui Hong Weijie Xu Liyang Shao Feng Wang 《Opto-Electronic Advances》 SCIE EI 2022年第3期25-52,I0001,共29页
Phase-sensitive optical time-domain reflectometry(Φ-OTDR)has attracted numerous attention due to its superior performance in detecting the weak perturbations along the fiber.Relying on the ultra-sensitivity of light ... Phase-sensitive optical time-domain reflectometry(Φ-OTDR)has attracted numerous attention due to its superior performance in detecting the weak perturbations along the fiber.Relying on the ultra-sensitivity of light phase to the tiny deformation of optical fiber,Φ-OTDR has been treated as a powerful technique with a wide range of applications.It is fundamental to extract the phase of scattering light wave accurately and the methods include coherent detection,I/Q demodulation,3 by 3 coupler,dual probe pulses,and so on.Meanwhile,researchers have also made great efforts to improve the performance ofΦ-OTDR.The frequency response range,the measurement accuracy,the sensing distance,the spatial resolution,and the accuracy of event discrimination,all have been enhanced by various techniques.Furthermore,lots of researches on the applications in various kinds of fields have been carried out,where certain modifications and techniques have been developed.Therefore,Φ-OTDR remains as a booming technique in both researches and applications. 展开更多
关键词 optical fiber sensors Ф-OTDR phase demodulation application research
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Design of Demodulation System of Interferometric Sensor Based on Labview 被引量:3
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作者 XU Wei WANG Jin-hai +2 位作者 CHEN Cai-he ZHENG Yu ZHANG Cheng 《Semiconductor Photonics and Technology》 CAS 2008年第2期115-120,共6页
For the modified demodulation arithmetic of 3×3 coupler, the processing software built on the basis of Labview is able to demodulate asymmetric 3×3 coupler signal and do further spectrum analysis. It shows t... For the modified demodulation arithmetic of 3×3 coupler, the processing software built on the basis of Labview is able to demodulate asymmetric 3×3 coupler signal and do further spectrum analysis. It shows that the measured frequency ranges from 10 Hz to 1 000 Hz and phase range is covered by -10 rad^10 rad. The phase sensitivity is 0.5 V/rad. This system is proved to show high resolution and wide dynamic range. 展开更多
关键词 asymmetric 3×3 coupler phase demodulation LABVIEW software demodulation interferometric sensor
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Fabry-Perot-based phase demodulation of heterodyne light-induced thermoelastic spectroscopy
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作者 Ziting Lang Shunda Qiao Yufei Ma 《Light(Advanced Manufacturing)》 2023年第3期233-242,共10页
Fabry-Perot(F-P)-based phase demodulation of heterodyne light-induced thermoelastic spectroscopy(H-LITES)was demonstrated for the first time in this study.The vibration of a quartz tuning fork(QTF)was detected using t... Fabry-Perot(F-P)-based phase demodulation of heterodyne light-induced thermoelastic spectroscopy(H-LITES)was demonstrated for the first time in this study.The vibration of a quartz tuning fork(QTF)was detected using the F-P interference principle instead of an electrical signal through the piezoelectric effect of the QTF in traditional LITES to avoid thermal noise.Given that an Fabry-Perot interferometer(FPI)is vulnerable to disturbances,a phase demodulation method that has been demonstrated theoretically and experimentally to be an effective solution for instability was used in H-LITES.The sensitivity of the F-P phase demodulation method based on the H-LITES sensor was not associated with the wavelength or power of the probe laser.Thus,stabilising the quadrature working point(Q-point)was no longer necessary.This new method of phase demodulation is structurally simple and was found to be resistant to interference from light sources and the surroundings using the LITES technique. 展开更多
关键词 Fabry-Perot(F-P)interferometer(FPI) phase demodulation Light-induced thermoelastic spectroscopy(LITES) Thermal noise
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A 330-W single-frequency retrievable multi-tone monolithic fiber amplifier 被引量:1
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作者 王小林 周朴 +2 位作者 冷进勇 杜文博 许晓军 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期274-280,共7页
A single-frequency retrievable phase modulated multi-tone fiber amplifier is presented in theory and demonstrated in experiment. A multi-tone seed laser generated by a sine wave phase modulated single-frequency laser ... A single-frequency retrievable phase modulated multi-tone fiber amplifier is presented in theory and demonstrated in experiment. A multi-tone seed laser generated by a sine wave phase modulated single-frequency laser is employed for stimulated Brillouin scattering suppression in an all-fiber amplifier. A demodulation signal which is π phase shifted with respect to the modulation signal is used to retrieve the single-frequency laser from the multi-tone laser. In experiment, we first optimize the all-fiber master-oscillator power-amplifier. With this amplifier, we demonstrate a single-frequency retrievable multi-tone laser with 330-W output when driven by the multi-tone seed, while the ultimate output power is only 130 W when driven by the single-frequency laser. Then, we carry out an experiment for retrieving the single-frequency laser from the amplified multi-tone laser. Results indicate that the single-frequency laser can be retrieved with a sideband suppression of more than 20 dB. Retrieving an even higher power single-frequency laser is possible if a high power demodulator is available. 展开更多
关键词 single-frequency laser multi-tone amplifier phase modulation and demodulation
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Recent Advances in Phase-Sensitive Optical Time Domain Reflectometry (Ф-OTDR) 被引量:10
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作者 Yunjiang RAO Zinan WANG +2 位作者 Huijuan WU Zengling RAN Bing HAN 《Photonic Sensors》 SCIE EI CAS CSCD 2021年第1期1-30,共30页
Phase-sensitive optical time domain reflectometry(Ф-OTDR)is an effective way to detect vibrations and acoustic waves with high sensitivity,by interrogating coherent Rayleigh backscattering light in sensing fiber.In p... Phase-sensitive optical time domain reflectometry(Ф-OTDR)is an effective way to detect vibrations and acoustic waves with high sensitivity,by interrogating coherent Rayleigh backscattering light in sensing fiber.In particular,fiber-optic distributed acoustic sensing(DAS)based on theФ-OTDR with phase demodulation has been extensively studied and widely used in intrusion detection,borehole seismic acquisition,structure health monitoring,etc.,in recent years,with superior advantages such as long sensing range,fast response speed,wide sensing bandwidth,low operation cost and long service lifetime.Significant advances in research and development(R&D)ofФ-OTDR have been made since 2014.In this review,we present a historical review ofФ-OTDR and then summarize the recent progress ofФ-OTDR in the Fiber Optics Research Center(FORC)at University of Electronic Science and Technology of China(UESTC),which is the first group to carry out R&D ofФ-OTDR and invent ultra-sensitive DAS(uDAS)seismometer in China which is elected as one of the ten most significant technology advances of PetroChina in 2019.It can be seen that theФ-OTDR/DAS technology is currently under its rapid development stage and would reach its climax in the next 5 years. 展开更多
关键词 Distributed optical fiber sensing phase-sensitive optical time domain REFLECTOMETRY Rayleigh backscattering optical phase demodulation distributed acoustic sensing long-distance sensing artificial intelligence
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FBG Arrays for Quasi-Distributed Sensing: A Review 被引量:8
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作者 Chengli LI Jianguan TANG +2 位作者 Cheng CHENG Longbao CAI Minghong YANG 《Photonic Sensors》 SCIE EI CAS CSCD 2021年第1期91-108,共18页
Fiber Bragg grating (FBG) array is a powerful technique for quasi-distributed sensing along the entire length of sensing fiber with fast response and high precision. It has been widely used for temperature, strain, an... Fiber Bragg grating (FBG) array is a powerful technique for quasi-distributed sensing along the entire length of sensing fiber with fast response and high precision. It has been widely used for temperature, strain, and vibration monitoring. In this review work, an overview on the recent advances of FBG arrays is conducted. Firstly, the fabrication methods of FBG array are reviewed, which include femtosecond laser system and online writing technique. Then, the demodulation techniques for FBG arrays are presented and discussed. Distributed static sensing can be performed by demodulating wavelength shift of each FBG, while phase demodulation techniques with low noise are employed for dynamic vibration sensing. Simultaneous distributed dynamic and static sensing system based on FBG array is also outlined. Finally, possible future directions are discussed and concluded. It is believed that the FBG array has great development potential and application prospect. 展开更多
关键词 FBG array on-line writing FBG wavelength demodulation phase demodulation
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