DISPERSION AND LOSS SPECTRUM SELF-CALIBRATION DISTRIBUTED OPTICAL FIBER RAMAN TEMPERATURE SENSOR

摘要

A dispersion and loss spectrum self-calibration distributed optical fiber Raman temperature sensor has a dual Raman displacement wavelength dual fiber pulsed laser module consisting of a drive 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 shift, wherein the optical fiber backward anti-Stokes Raman scattering peak centre wavelength of the primary light source and the optical fiber backward Stokes scattering peak centre wavelength of the secondary light source are coincided, 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 self-calibration method and the optical time domain reflection principle, the optical fiber dispersion and the loss spectrum can be self-calibrated, and the random loss of the temperature-measurement optical fiber and the optical cable used on site caused by bending and pressed stretching can also be self-calibrated.