Research on FBG Wavelength Demodulation System Based on Tilted Fiber Grating

摘要

In this paper, the fiber Bragg gratings wavelength demodulation system based on tilted fiber grating is designed. The temperature sensing characteristic is researched. The demodulation system is formed by a tilted fiber grating, four sensing FBGs, One broadband light source and four photodetectors. The tilted fiber grating is as edge filter. The central wavelengths of the four FBGs are 1560.0nm, 1561.5nm. 1563.0nm and 1564.5nm respectively. When the temperature increases gradually from 0 °C to 105 °C, the simulation results show that the demodulation range of four FBGs is from 1560.0nm-1566nm, the sensitivity of FBG1,FBG2,FBG3 and FBG4 are 0.458 mW/°C, 0.564mw/°C, 0.651mw/°C and 0.559mw/°C, respectively. This system provides a new demodulation scheme for array sensing.