This paper reports the results of our recent investigation on the noise limited performance in heterodyne interferometric demodulation systems for fiber Bragg grating strain sensors. Theoretical and simulation results are presented and compared with experimental results.
A fiber Bragg grating (FBG) sensor system for multi point, dynamic strain or temperature measurement is reported. The system uses a combination of an unbalanced fiber interferometer and phase locked loops and is capable of measuring dynamic signals with frequencies ranging from 100Hz to10kHz. Strain measurements with parallel FBG sensor arrays demonstrate strain resolution of better than 27.5n?/?Hz and measurement range of 0-3400?? at10kHz.
In this paper, we measure the dispersion characteristic of chalcogenide fiber. We use phase shift method to measure the dispersion characteristic of single mode As2S3 fiber around 1 .55 im. Measurement show the strong dispersion of about -39 ps/kmnm at communication wavelength of 1 .55 um. Chalcogenide fiber has promising market as dispersion compensation device with such good performance.