We have proposed and constructed a system to multiplex fiber Bragg grating (FBG) strain sensors with same reflection wavelength, adopting the synthesis of optical coherence function technique (SOCF), which has realized dynamic strain measurement. The ability to control the coherence peak position of SOCF allows random access in the spatial domain. In this paper, the function of random access strain measurement has been realized by switching the coherence peak position at every FBG, synchronizing with FBG spectrum measurement, to use the sampling rate to the full. In addition, we have proposed and confirmed the novel method for improving FBG interval by simply modulating the LD intensity.
In this paper, a novel technique for multiplexed fiber Bragg grating (FBG) sensors is proposed. Applying the synthesis of optical coherence function, we can select the signal, which has a specific time delay with the reference light wave, and therefore FBG array with the same reflection wavelength can be used.