Device and method for simultaneous sensing and measurement of optical fiber distributed dynamic and static parameters

Abstract

The invention discloses a device and method for simultaneously sensing and measuring optical fiber distributed dynamic and static parameters, wherein the device includes: a broadband light source and a narrowband DFB laser source connected to a polarization scrambler through a wavelength multiplexer; an optical / acousto-optic modulator , connected with the polarization scrambler; the modulator driver module, connected with the electro-optic / acousto-optic modulator; the erbium fiber amplifier EDFA, connected with the electro-optic / acousto-optic modulator; the first circulator, the second circulator, the third circulator, The coupler, data acquisition and signal processing module are connected with four photodetectors to collect signals and perform phase demodulation to realize the quasi-static measurement of the narrowband weak grating array and the dynamic sensing measurement of the broadband chirped weak grating array. The invention can realize simultaneous sensing and measurement of optical fiber distributed dynamic and static parameters.

Description

technical field [0001] The invention relates to the technical field of optical fiber sensing, in particular to a device and method for simultaneously sensing and measuring optical fiber distributed dynamic and static parameters. Background technique [0002] Fiber optic sensing technology has many good advantages over electrical sensors. Facing the huge demand of the rapid development of the Internet of Things industry, fiber optic sensing technology is facing new opportunities and challenges, but there is a contradiction between the diversity of fiber optic sensing requirements and the singleness of fiber optic sensing functions. In the exploitation and detection of oil and gas wells, oil and gas pipelines, bridges, large pipe galleries, etc., if dynamic and static signals can be monitored at the same time, the cost of the monitoring system can be greatly reduced, and the effectiveness and reliability of monitoring can be improved. [0003] Based on light backscattering te...

AI Technical Summary

Problems solved by technology

[0003] Based on light backscattering technology sensing, it can be used to measure quasi-static physical quantities such as temperature and strain. For example, Brillouin scattering technology can measure temperature or strain in a distributed manner; the other is to use the interference effect in optical fibers to measure dynamic signals such as vibration. For example, based on the Rayleigh scattering light polarization effect, C-OTDR, Sagnac interference and Mach-Zehnder interference, this type of technology uses the phase or polarization information of light waves in the optical fiber, and is very sensitive to rapidly changing dynamic signals, but cannot measure quasi-static temperature / strain parameter

Some scholars have used Raman scattering or Brillouin scattering and Φ-OTDR fusion to realize the distributed demodulation of dynamic and static sensing signals, but the signal-to-noise ratio of the system is poor and the system cost is high

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