基于频分复用和数字相干探测的高测量带宽相敏光时域反射技术研究

Phase-sensitive optical time-domain reflectometry (Phase-OTDR) is an advanced technology in the field of distributed fiber sensing. Phase-OTDR can feel micro-perturbation signal along the fiber link with a high sensitivity. Therefore, it has wide application foreground in the long distance security defences. In this project, by analyzing the development states of Phase-OTDR and introducing the new progress of optical communication, a novel Phase-OTDR technology based on the optical frequency-division multiplexing and digital coherent detection technologies will be investigated in order to solve some key bottle-neck problems, such as low signal-to-noise ratio (SNR), non-quantitative phase detection and low sampling rate. The main contents include: coherent detection of weak Rayleigh scattering, the phase demodulation in the background with severe coherent noise, the accurate phase measurement by digital filter compensation technology. Moreover, a optical frequency-division multiplexing technology is introduced to solve the conflict between the measurement distance and sampling rate, which will realize high-speed measurement of long-distance distributed perturbation. The research work of this project will not only accelerate the development of Phase-OTDR, but also provide some new ideas and directions for other types of distributed fiber sensing technologies.

相位敏感光时域反射计(Phase-OTDR)是分布式光纤传感领域的前沿技术，它能够高灵敏度动态感知光纤沿线任意位置的微小扰动，对实时长距离安全监测具有非常广泛的应用前景。本项目通过分析国内外Phase-OTDR的发展动态及结合相关光通信技术的快速发展，拟开展基于光频分复用及数字相干检测的Phase-OTDR传感技术的研究，以期突破目前相关领域发展所面临的低信噪比，非相位定量检测，低采样速率等若干瓶颈问题。项目研究内容主要包括微弱瑞利散射光的相干检测、严重相干噪声背景下的相位解调、数字滤波补偿技术实现相位精确测量等关键技术，同时创新性引入光频分复用技术来解决OTDR类分布式传感系统中测量距离与采样率的根本矛盾，使长距离分布式扰动信号的高速测量成为可能。项目的研究将不仅极大地推动Phase-OTDR的技术发展，而且为其它的分布式光纤传感技术提供很好借鉴意义，从而有效促进光纤传感领域的蓬勃发展。

相位敏感光时域反射计(Phase-OTDR)是分布式光纤传感领域的前沿技术，它能够高灵敏度动态感知光纤沿线任意位置的微小扰动，对实时长距离安全监测具有非常广泛的应用前景。本项目通过分析国内外Phase-OTDR的发展动态及结合相关光通信技术的快速发展，开展了基于光频分复用及数字相干检测的Phase-OTDR传感技术的研究，突破了目前相关领域发展所面临的低信噪比，非相位定量检测，低采样速率等若干瓶颈问题。项目研究内容主要包括微弱瑞利散射光的相干检测、严重相干噪声背景下的相位解调、数字滤波补偿技术实现相位精确测量等关键技术，同时创新性引入光频分复用技术来解决OTDR类分布式传感系统中测量距离与采样率的根本矛盾，使长距离分布式扰动信号的高速测量成为可能。项目的研究将不仅极大地推动Phase-OTDR的技术发展，而且为其它的分布式光纤传感技术提供很好借鉴意义，从而有效促进光纤传感领域的蓬勃发展。