Distributed type fiber sensing device based on signal reusing perception and demodulation

Abstract

The invention provides a distributed type fiber sensing device based on signal reusing perception and demodulation, comprising a laser, a first fiber coupler, a second fiber coupler, a light pulse modulator, a fiber annular device, an optical interface, a balance photoelectric detector, a low noise amplifier, a power divider, a first filter, a second filter, a frequency synthesizer, a mixer, a lowpass filter, a data collecting and processing module, and a computer. The feature that rayleigh scattering signals and Brillouin scattering signals can be generated at the same time is taken into consideration, and by means of the balance photoelectric detector, the rayleigh scattering signals and Brillouin scattering signals of the detection light pulse, generated in the detected fiber are simultaneously converted into radiofrequency signals of the corresponding frequency or frequency range. The rayleigh scattering signals and the Brillouin scattering signals are separated by means of the power divider and a band pass filter. The separated rayleigh scattering signals and the Brillouin scattering signals are accessed to the data collecting and processing module. The attenuation, vibration, and monitoring and displaying of the temperature and strain information of the fiber can be realized.

Description

technical field [0001] The invention relates to the technical field of optical fiber sensing, in particular to a distributed optical fiber sensing device based on signal multiplexing sensing and demodulation. Background technique [0002] Since optical fiber can also be used as a communication and sensing medium, its passive, anti-electromagnetic interference, corrosion resistance, high temperature resistance and other characteristics determine its great potential in the development of global energy Internet. Mature optical fiber sensing technology and equipment have been applied in the electric power industry, such as Raman optical time domain reflectometer for transformer temperature monitoring, Brillouin optical time domain reflectometer for submarine cable temperature / stress monitoring, Brillouin optical time domain reflectometer for submarine cable temperature / stress monitoring, Yuanguang time-domain analyzer is used for icing monitoring of transmission lines, applicati...

AI Technical Summary

Problems solved by technology

However, this device is only a device required for the fusion of multi-parameter sensing functions based on the distributed optical fiber sensing hardware architecture, and has not yet involved the characteristics of multiplexing and coexistence of Rayleigh scattering signals and Brillouin scattering signals in optical fibers. Rather than sensing and demodulating at the same time, the realization of system functions is relatively complicated

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