1 华中科技大学光学与电子信息学院，下一代互联网接入系统国家工程研究中心，武汉光电国家研究中心，湖北 武汉 430074
2 华中科技大学未来技术学院，湖北 武汉 430074
分布式光纤传感器以光纤作为传输和传感融合的介质，具有高灵敏、全分布、大尺度、高分辨的独特优势，近年来受到多个应用领域研究人员的关注并逐步进入产业化。然而，现有普通单模光纤在传感信噪比与稳定性等方面仍存在局限性。以散射增强微结构特种光纤为传感载体，研究其分布式传感增效机理，介绍了其自动化、高效率刻写制备技术，并重点阐述了其分布式光纤传感技术研究进展与相关应用。进一步对散射增强微结构传感光纤的未来发展潜力及应用方向进行了展望。
传感器 分布式光纤传感 散射增强光纤 分布式声波传感 光频域反射技术
Author Affiliations
Abstract
1 School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
2 HUST-Wuxi Research Institute, Wuxi 214174, China
3 Guangdong Key Laboratory of Integrated Optoelectronics Intellisense, Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
4 Optics Valley Laboratory, Wuhan 430074, China
Optical fiber distributed acoustic sensing (DAS) based on phase-sensitive optical time domain reflectometry (φ-OTDR) is in great demand in many long-distance application fields, such as railway and pipeline safety monitoring. However, the DAS measurement distance is limited by the transmission loss of optical fiber and ultralow backscattering power. In this paper, a DAS system based on multispan relay amplification is proposed, where the bidirectional erbium-doped fiber amplifier (EDFA) is designed as a relay module to amplify both the probe light and the backscattering light. In the theoretical noise model, the parameters of our system are carefully analyzed and optimized for a longer sensing distance, including the extinction ratio (ER), span number, span length, and gain of erbium-doped fiber amplifiers. The numerical simulation shows that a bidirectional EDFA relay DAS system can detect signals over 2500 km, as long as the span number is set to be more than 100. To verify the effectiveness of the scheme, a six-span coherent-detection-based DAS system with an optimal design was established, where the cascaded acoustic-optic modulators (AOMs) were used for a high ER of 104 dB. The results demonstrate that the signal at the far end of 300.2 km can be detected and recovered, achieving a high signal-to-noise ratio of 59.6 dB and a high strain resolution of at 50 Hz with a 20 m spatial resolution. This is, to the best of our knowledge, a superior DAS sensing distance with such a high strain resolution.
Photonics Research
2023, 11(6): 968
1 华中科技大学光学与电子信息学院，武汉光电国家研究中心，湖北 武汉 430074
2 下一代互联网接入系统国家工程实验室，湖北 武汉 430074
3 华中科技大学无锡研究院，江苏 无锡 214174
基于相位敏感光时域反射技术的分布式声波传感（DAS）系统可实现大范围分布式的声波探测，近年来，在油气勘探、地质成像、管道安全、周界安防等应用领域受到研究关注。本文论述了光纤DAS技术的传感原理，分析了单模光纤的衰落机理和性能瓶颈。针对此问题，分别介绍了多种散射增强光纤的增效机理与声波传感性能。进一步，围绕微结构散射增强光纤DAS系统，综述了其近年来的技术与应用进展，并展望了其未来可能的发展方向。
光纤光学 光纤传感 相敏光时域反射计 分布式声波传感 散射增强光纤 激光与光电子学进展
2022, 59(21): 2100001
Author Affiliations
Abstract
1 Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education, Taiyuan University of Technology, Taiyuan, 030024, China
2 College of Physics and Optoelectronics, Institute of Optoelectronic Engineering, Taiyuan University of Technology, Taiyuan, 030024, China
In Raman distributed temperature system, the key factor for performance improvement is noise suppression, which seriously affects the sensing distance and temperature accuracy. Therefore, we propose and experimentally demonstrate dynamic noise difference algorithm and wavelet transform modulus maximum (WTMM) to de-noising Raman anti-Stokes signal. Experimental results show that the sensing distance can increase from 3 km to 11.5 km and the temperature accuracy increases to 1.58 ℃ at the sensing distance of 10.4km.
Optical fiber sensors Raman scattering noise suppression wavelet transform modulus maximum Photonic Sensors
2018, 8(2): 103
