Combining modified Manchester modulation with optical equalization for improved dispersion tolerance in IM/DD access networks

Abstract In this paper the intensity modulation and direct detection of an optical link utilizing a Modified Manchester (MM) signal at the bitrate of 10 Gb/s and 25 Gb/s are presented for long-reach optical access networks. First-order and second-order optical equalizer were utilized to compensate the distortion in MM signal waveform caused by the chromatic dispersion in standard single mode fiber (SSMF). The assessment of the system performance was centered on bit error rate (BER), power penalty, eye diagrams and chromatic dispersion tolerance. Based on the calculated results the use of second-order optical equalizer, can extend the transmission distance by 20 km (SSMF) and 3.5 km at 10 Gb/s and 25 Gb/s, respectively. Based on the calculated results, the use of second-order optical equalizer is therefore promising in the next generation of long-reach optical access networks.