Exact analysis of intermodal dispersion compensation in spliced graded-index optical fibers

Intermodal dispersion compensation in spliced graded-index optical fiber is investigated. Group delay times of modes in individual and spliced fibers are exactly analyzed using the Wentzel-Kramers-Brillouin (WKB) method. It is found that in actual fibers whose refractive index profiles are not represented by the power-law function, the compensation effect is less remarkable than that predicted from the power-law approximation. The baseband bandwidth of spliced fiber, composed of under- and over-compensated index profile fibers, is calculated based on the measured index profile. As a result, the measured bandwidth is found to be well predicted with an error less than 5 percent.