Pulse coding extra-long distance fully-distributed fiber Rayleigh and Raman scattering sensor of fusion fiber Raman frequency shift device

Abstract

The invention discloses a pulse coding extra-long distance fully-distributed fiber Rayleigh and Raman scattering sensor of a fusion fiber Raman frequency shift device. The sensor comprises a pulse coding fiber laser drive power supply, a pulse coding fiber pulse laser, a fiber Raman frequency shift device consisting of a single mode fiber and a 1,660nm bandpass filter, an integrated fiber wavelength division multiplexer, a sensing fiber, a photoelectric receiving module, a coder-decoder demodulation digital signal processor and an industrial personal computer. The sensor is used for positioning a measuring point on the basis of a fiber Raman frequency shift device principle, a pulse coding principle and a fiber Rayleigh and Raman fusion scattering sensing principle by using an optical time domain reflection principle. The sensor has low cost, long service life, a simple structure, high signal-to-noise ratio and high reliability and is suitable for large-scale civil engineering monitoring and hazard forecast monitoring of petrochemical pipelines and tunnels within a long distance and extra-long distance 80-kilometer range.

Description

technical field [0001] The invention relates to the field of optical fiber sensors, in particular to a pulse code ultra-long-distance fully distributed optical fiber Rayleigh and Raman scattering sensor fused with an optical fiber Raman frequency shifter. Background technique [0002] For a long time, in the field of engineering at home and abroad, large-scale civil construction, bridges, tunnels, petrochemical pipelines, oil storage tanks and power cables have mainly used electrical strain gauges and thermosensitive electric groups as strain and temperature sensors, and each sensor needs to be connected with wires. , to form a large-scale detection network, the structure is very complicated, this kind of sensor itself is charged, it is inherently unsafe, susceptible to electromagnetic interference, not resistant to corrosion, and cannot be positioned, not suitable for use in harsh environments, let alone applied geology Scenes of disasters and fires. [0003] The optic...

AI Technical Summary

Problems solved by technology

However, it can no longer meet the safety and health monitoring of oil pipelines and transmission power cables in recent years, and the urgent demand for ultra-long-distance fully distributed optical fiber Rayleigh, Raman and Brillouin scattering strain and temperature sensor networks

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