A comprehensive study of the chromatic dispersion measurement of the multi-channel fiber Bragg grating based on an asymmetrical Sagnac loop interferometer

A novel all-fiber asymmetrical Sagnac loop interferometer (ASLI) is proposed to measure the chromatic dispersion of a multi-channel fiber Bragg grating (FBG). Theoretical analyses to this proposed approach are presented in details. With this method, the chromatic dispersion and dispersion slope of a 51-channel FBG are simultaneously measured. The experimental results agree well with the ones obtained by using the general phase-shift method (PSM). This method has the advantages of simple configuration, low-cost, and high tolerance for the characteristics of FBG.