Abstract:Based on coupling-mode theory,the reflective spectrum of sampled fiber Bragg grating was analyzed using transmission matrix method.Wavelength shift and reflectivity vary linearly with strain and temperature.The change of strain and temperature can be determined simultaneously by a single sampled fiber grating.In the experiment,the strain and temperature of sampled fiber Bragg grating change simultaneously.The function of reflectivity and wavelength on temperature and strain can be got using SPSS13.0.We can get that A,B,C and D were separately-0.00033/με,-0.00011/℃,-0.00055nm/με,0.013nm/℃,by calculating.Strain measurement ranged from 0με to 1800με.Temperature measurement ranged from 0℃ to 180℃.