Simultaneous strain and temperature measurement system with fiber Bragg grating

摘要

Simultaneous strain and temperature measurement system with fiber Bragg grating was presented in this paper. The light from broadband source (BBS) was coupled into sensing probe through 3dB coupled. Reflective light of two FBGs was split through coupler2 and went into chirped gratings with different pass-band. Demodulation method adopted chirped grating and long period grating edge linear filtering technology. It can send each reflected spectrum to different edge filter. It makes every FBG's reflective spectrum was demodulate. The central reflected wavelength of two FBGs was 1546.15nm and 1554.17nm respectively. Through simulation experiment, we can get that K_(T1) =14.29pm/ °C , K_(ε2) = 1.03 pm/fxs , K_(T2) =13.39 pm/°C " Strain measurement ranged from 0 to 2000 με , Temperature measurement ranged from 0 to 200 °C.