Polymer microcavity filling micro-structured optical fiber based quasi-distributed temperature sensing system and its signal demodulation method

Abstract

The invention discloses a polymer microcavity filling micro-structured optical fiber based quasi-distributed temperature sensing system and its signal demodulation method. The system includes a broadband light source, an optical isolator, an optical circulator, an optical fiber coupler, a single mode optical fiber, polymer microcavity filling microstructure optical fiber sensors, a spectrum analyzer and a computer, wherein the broadband light source is connected to the optical circulator through the optical isolator, an output port of the optical circulator is connected to one end of the optical fiber coupler, the optical fiber coupler has multiple output interfaces, the multiple output interfaces are connected to multiple polymer microcavity filling microstructure optical fiber sensors after passing through the single mode optical fiber, and the other output port of the optical circulator is connected to an input end of the spectrum analyzer to obtain temperature information of multiple monitoring sites. The polymer microcavity filling micro-structured optical fiber based quasi-distributed temperature sensing system has characteristics of multi-node distributed sensing, quick response, high sensitivity, simple and stable system, low cost and so on.

Description

technical field [0001] The invention belongs to the field of sensing technology, and specifically refers to a quasi-distributed temperature sensing system based on a polymer microcavity filled microstructure optical fiber and a signal demodulation method thereof. Background technique [0002] Temperature monitoring plays a vital role in the healthy operation of power systems, oil mines, bridge construction, submarine optical cables and other major projects. It is an urgent demand and development trend to ensure the safe operation of these facilities to carry out distributed online temperature monitoring of these engineering facilities, to obtain the law of internal temperature changes and assess their dangerous conditions as soon as possible. As a very effective distributed online temperature monitoring method, fiber optic sensing has been highly valued by many countries. [0003] Compared with traditional optical fibers, microstructured optical fibers or photonic crystal o...

AI Technical Summary

Problems solved by technology

However, the temperature sensing of selectively filled microstructured optical fibers still faces the constraints of many factors, such as (1) the directional coupling matching conditions are complex, and it is necessary to precisely control the filling material and the structural parameters of the microstructured optical fiber; (2) some properties of the filling material (such as High loss, harmfulness, instability, etc.) limit the application of microstructure optical fiber temperature sensing; (3) The complex air hole design increases the difficulty of device preparation; (4) Distributed temperature monitoring is generally concerned in engineering applications not enough exploration

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