Patent ID: 9157811
Filing Date: 2015-10-13
Classification: G01K

Abstract:
1. A dispersion and loss spectrum auto-correction distributed optical fiber Raman temperature sensor, comprising: a dual fiber pulsed laser module having dual Raman shift wavelengths, the laser module including a power supply, an electronic switch, a primary laser having a primary laser wavelength, and a secondary laser having a secondary laser wavelength; a first combiner; a bidirectional coupler; a multimode optical fiber; an integrated optical fiber wavelength division multiplexer; a second combiner; a direct detection system; a signal collection and processing system; and a display; wherein output terminals of the primary laser and the secondary laser are connected with an input terminal of the first combiner, an output terminal of the first combiner is connected with an input terminal of the bidirectional coupler, and an output terminal of the bidirectional coupler is connected with an input terminal of the multimode optical fiber; wherein backward Rayleigh scattering and Raman scattering echoes of the multimode optical fiber enter an input terminal of the integrated optical fiber wavelength division multiplexer via the bidirectional coupler, the integrated optical fiber wavelength division multiplexer having three output ports, the first output port being an output port for a central wavelength of Raman scattering peak, the central wavelength of Raman scattering peak including an anti-Stokes Raman scattering wave of the primary laser and a Stokes Raman scattering wave of the secondary laser within the same waveband, the second output port being an output port for an optical fiber backward Rayleigh scattering wave of the primary laser wavelength, and the third output port being an output port for the optical fiber backward Rayleigh scattering wave of the secondary laser wavelength; wherein the first output port of the integrated optical fiber wavelength division multiplexer is connected with an input terminal of the direct detection system, the second and third output ports of the integrated optical fiber wavelength division multiplexer are connected with two input terminals of the second combiner, an output terminal of the second combiner is connected with another input terminal of the direct detection system, an output terminal of the direct detection system is connected with an input terminal of the signal collection and processing system, and an output terminal of the signal collection and processing system is connected with the display.