Ultra-long-range (ULR) full-distributed optical Rayleigh and Raman scattering sensor fused with optical Raman frequency shifter

Abstract

The invention discloses a ultra-long-range (ULR) full-distributed optical Rayleigh and Raman scattering sensor fused with an optical Raman frequency shifter. Based on an optical Raman frequency shift theory and an optical Rayleigh and Raman fusion scattering sensing theory, an optical Raman frequency shifter is adopted, and an integrated optical wavelength-division multiplexing (WDM) and an optical time domain reflection (OTDR) principle are utilized to locate landmarks. The sensor comprises an optical pulse laser, the optical Raman frequency shifter composed of single mode fibers (SMF) and 1660mn bandpass filters, an integrated optical wavelength-division multiplexer, a sensor fiber, a photoelectric receiving module, a digital signal processor (DSP) and a computer. The sensor has the advantages of low cost, long service life, good signal to noise ratio (SNR) and good reliability, is simple in structure, and is applied to monitoring petrochemical pipes, tunnels, large civil engineering in 15-60km of long range and ultra long range and monitoring hazard forecast.

Description

technical field

[0001] The invention relates to the field of optical fiber sensors, in particular to an 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. , forming 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 optical fiber senso...

Examples

Embodiment Construction

[0035] refer to figure 1 , an ultra-long-range fully distributed optical fiber Rayleigh and Raman scattering sensor fused with a fiber optic Raman frequency shifter, including a fiber optic pulse laser 11, a fiber optic Raman frequency shifter composed of a single-mode fiber 12 and a 1660nm bandpass filter 13 , an integrated optical fiber wavelength division multiplexer 14, a sensing optical fiber 15, a photoelectric receiving module 16, a digital signal processor 17 and a computer 18. The input end of the single-mode fiber 12 is connected with the fiber pulse laser 11, and the integrated fiber wavelength division multiplexer 14 has four ports, wherein the 1660nm input port is connected with the 1660nm bandpass filter 13, and the COM output port is connected with the sensing fiber 15 The 1550nm output port is connected to one input terminal of the photoelectric receiving module 16, the 1660nm output port is connected to the other input terminal of the photoelectric receiving m...

technical field

[0001] The invention relates to the field of optical fiber sensors, in particular to an 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. , forming 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 optical fiber senso...

Examples

Embodiment Construction

[0035] refer to figure 1 , an ultra-long-range fully distributed optical fiber Rayleigh and Raman scattering sensor fused with a fiber optic Raman frequency shifter, including a fiber optic pulse laser 11, a fiber optic Raman frequency shifter composed of a single-mode fiber 12 and a 1660nm bandpass filter 13 , an integrated optical fiber wavelength division multiplexer 14, a sensing optical fiber 15, a photoelectric receiving module 16, a digital signal processor 17 and a computer 18. The input end of the single-mode fiber 12 is connected with the fiber pulse laser 11, and the integrated fiber wavelength division multiplexer 14 has four ports, wherein the 1660nm input port is connected with the 1660nm bandpass filter 13, and the COM output port is connected with the sensing fiber 15 The 1550nm output port is connected to one input terminal of the photoelectric receiving module 16, the 1660nm output port is connected to the other input terminal of the photoelectric receiving m...

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