Comparison of Different Modulation Formats for 1-Gb/s SI-POF Transmission Systems

In the framework of the currently ongoing effort to find the best transmission solution for Gigabit Ethernet over step-index polymer optical fiber (SI-POF), we give a novel contribution through the comparison of three possible modulation formats: pulse amplitude modulation (PAM)-2, PAM-4, and duobinary, all coupled with electronic equalization at the receiver. We show that on a 50-m SI-POF link using resonant cavity light-emitting diode (RC-LED), duobinary gives the best performance, followed by PAM-2 and then by PAM-4. All evaluations were performed by offline processing experiments.