Transmission of 56-Gb/s PAM-4 signal over 2.3 km of MMF using mode-field matched center-launching technique

We demonstrate the transmission of 56-Gb/s PAM-4 signal generated by using a 1.55¼m directly-modulated DFB laser over 2.3 km of OM3 fiber. In this experiment, the mode-field matched center-launching technique is utilized to excite only the fundamental mode of OM3 fiber and electrical equalizers are used for the compensation of fibers chromatic dispersion.