DISPERSION AND LOSS SPECTRUM AUTO-CORRECTION DISTRIBUTED OPTICAL FIBER RAMAN TEMPERATURE SENSOR

摘要

A dispersion and loss spectrum auto-correction distributed optical fiber Raman temperature sensor has a dual fiber pulsed laser module with dual Raman wavelength shifts. The laser module is composed of a power supply (11), an electronic switch (12), a primary laser (13) and a secondary laser (14), a first combiner (15), a bidirectional coupler (16), a multimode fiber (17), an integrated optical fiber wavelength division multiplexer (18), a second combiner (19), a direct detection system (20), a signal collection and processing system (21) and a display (22). The sensor uses two light sources that have two Raman wavelength shifts, wherein the central wavelength of backward anti-Stokes Raman scattering peak of the primary light source coincides with that of the backward Stokes scattering peak centre wavelength of the secondary light source, and the time domain reflection signal of the one-way optical fiber Rayleigh scattering is deducted. Based on the optical fiber Raman scattering temperature measurement principle, the dispersion and loss spectrum auto-correction method and the optical time domain reflection principle, the optical fiber dispersion and the loss spectrum can be self-corrected, and the random power loss caused by bending and stretching in installation can also be auto-corrected.