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
The application of Golay pulse coding technique in spontaneous Brillouin-based distributed temperature sensor based on self-heterodyne detection of Rayleigh and Brillouin scattering is theoretically and experimentally...The application of Golay pulse coding technique in spontaneous Brillouin-based distributed temperature sensor based on self-heterodyne detection of Rayleigh and Brillouin scattering is theoretically and experimentally analyzed. The enhancement of system signal to noise ratio(SNR) and reduction of temperature measurement error provided by coding are characterized. By using 16-bit Golay coding, SNR can be improved by about 2.77 d B, and temperature measurement error of the 100 m heated fiber is reduced from 1.4 °C to 0.5 °C with a spatial resolution of 13 m. The results are believed to be beneficial for the performance improvement of self-heterodyne detection Brillouin optical time domain reflectometer.展开更多
光纤通信网络作为现代信息传输的重要基础设施,其稳定性和可靠性直接关系到网络的整体性能。光缆终端盒作为光纤网络的关键节点,故障不仅会导致通信中断,而且可能引发严重的经济损失。通过研究光缆终端盒的常见故障类型和成因,探讨多种...光纤通信网络作为现代信息传输的重要基础设施,其稳定性和可靠性直接关系到网络的整体性能。光缆终端盒作为光纤网络的关键节点,故障不仅会导致通信中断,而且可能引发严重的经济损失。通过研究光缆终端盒的常见故障类型和成因,探讨多种故障诊断技术,包括光时域反射仪(Optical Time Domain Reflectometer,OTDR)、光功率监测技术以及可视化光缆测试仪,以提升故障诊断准确性和效率。展开更多
随着电力通信网络的不断发展,光缆作为传输介质的可靠性受到极大关注。光缆故障不仅会影响通信的稳定性,还会给电力系统的正常运行带来不利影响。因此,快速且准确地定位光缆故障点,并及时处理,已成为电力通信网络管理的重要任务。光时...随着电力通信网络的不断发展,光缆作为传输介质的可靠性受到极大关注。光缆故障不仅会影响通信的稳定性,还会给电力系统的正常运行带来不利影响。因此,快速且准确地定位光缆故障点,并及时处理,已成为电力通信网络管理的重要任务。光时域反射仪(Optical Time Domain Reflectometer,OTDR)曲线事件分析技术是光缆故障定位的核心技术。文章通过分析OTDR曲线事件分析技术,研究改进OTDR曲线事件分析技术,结合地理信息系统(Geographic Information System,GIS)技术设计电力通信光缆故障精确定位方案,并针对不同故障提出相应的处置对策。本研究旨在为电力通信网络中的光缆故障检测与定位提供技术支持,同时为提升电力通信网络的稳定性和可靠性提供理论依据。展开更多
基金The authors would like to thank all of the members in the FORC at UESTC for their hard work and important contributions to this workThis work was funded by the Natural Science Foundation of China(Grant Nos.41527805 and 61635005)the 111 Poject(Grant No.B14039).
文摘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.
基金supported by the National Natural Science Foundation of China(No.61377088)the Natural Science Foundation of Hebei Province of China(Nos.E2015502053 and F2014502098)
文摘The application of Golay pulse coding technique in spontaneous Brillouin-based distributed temperature sensor based on self-heterodyne detection of Rayleigh and Brillouin scattering is theoretically and experimentally analyzed. The enhancement of system signal to noise ratio(SNR) and reduction of temperature measurement error provided by coding are characterized. By using 16-bit Golay coding, SNR can be improved by about 2.77 d B, and temperature measurement error of the 100 m heated fiber is reduced from 1.4 °C to 0.5 °C with a spatial resolution of 13 m. The results are believed to be beneficial for the performance improvement of self-heterodyne detection Brillouin optical time domain reflectometer.
文摘光纤通信网络作为现代信息传输的重要基础设施,其稳定性和可靠性直接关系到网络的整体性能。光缆终端盒作为光纤网络的关键节点,故障不仅会导致通信中断,而且可能引发严重的经济损失。通过研究光缆终端盒的常见故障类型和成因,探讨多种故障诊断技术,包括光时域反射仪(Optical Time Domain Reflectometer,OTDR)、光功率监测技术以及可视化光缆测试仪,以提升故障诊断准确性和效率。
文摘随着电力通信网络的不断发展,光缆作为传输介质的可靠性受到极大关注。光缆故障不仅会影响通信的稳定性,还会给电力系统的正常运行带来不利影响。因此,快速且准确地定位光缆故障点,并及时处理,已成为电力通信网络管理的重要任务。光时域反射仪(Optical Time Domain Reflectometer,OTDR)曲线事件分析技术是光缆故障定位的核心技术。文章通过分析OTDR曲线事件分析技术,研究改进OTDR曲线事件分析技术,结合地理信息系统(Geographic Information System,GIS)技术设计电力通信光缆故障精确定位方案,并针对不同故障提出相应的处置对策。本研究旨在为电力通信网络中的光缆故障检测与定位提供技术支持,同时为提升电力通信网络的稳定性和可靠性提供理论依据。
