Phi-OTDR reinforcing method based on polarized orthogonal optical pulse pair and device thereof

Abstract

The invention discloses a phi-OTDR reinforcing method based on a polarized orthogonal optical pulse pair, wherein a polarized orthogonal optical pulse pair set is used as a detecting optical signal. After detecting light enters a sensing optical fiber, two sets of optical fiber back Rayleigh scattering curves of the orthogonal optical signals are obtained. Mean processing is performed on the two sets of curves, thereby eliminating sensitivity of an optical fiber to the polarized state of the detecting light in a phi-OTDR method, and effectively ensuring capability of a phi-OTDR system for simultaneously detecting multiple events. The invention further discloses a device according to the phi-OTDR reinforcing method based on the polarized orthogonal optical pulse pair. The device is additionally provided with a polarization maintaining switch unit in a traditional OTDR system, thereby generating the polarized orthogonal optical pulse pair which is required in detection. Furthermore a pulse generator adjusts a sequential relationship among the polarization maintaining switch unit, an acoustic-optical modulator and a subsequent data processing unit. The phi-OTDR reinforcing method and the device thereof have functions of eliminating sensitivity of the optical fiber to the polarized state of the detecting light in the phi-OTDR method, effectively ensuring the capability of the phi-OTDR system for simultaneously detecting multiple events, and greatly reducing cost of a detecting system.

Description

technical field [0001] The invention relates to the field of optical fiber technology, in particular to a Φ-OTDR enhancement method and device based on a polarization state orthogonal optical pulse pair. Background technique [0002] With the development of the economy, large-scale infrastructure engineering facilities such as bridges, tunnels, dams and other large buildings, as well as highways and railways, power distribution networks, oil and gas pipelines, etc. are constantly being constructed and popularized, so that they can be safely and healthily constructed and potential threats can be detected in time , It is becoming more and more important to ensure the safety of the country and people's lives and property. Safety monitoring work such as structural fault diagnosis and accident warning of these large-scale engineering projects needs to meet the requirements of long monitoring distance, high precision, flexible placement, and real-time continuous monitoring. The o...

AI Technical Summary

Problems solved by technology

In this field, some researchers use full-range polarization-maintaining fiber to eliminate the influence of disturbance events on the polarization state of the probe light, but the cost is too high for practical applications, especially for long-distance sensing and monitoring applications.

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