title: Transmission of 2 × 56 Gb/s PAM-4 signal over 100 km SSMF using 18 GHz DMLs.
abstract: We experimentally demonstrate C-band 2 × 56 Gb/s pulse-amplitude modulation (PAM)-4 signal transmission over 100 km standard single-mode fiber (SSMF) using 18 GHz direct-modulated lasers (DMLs) and direct detection, without inline optical amplifier. A delay interferometer (DI) at the transmitter side is used to extend the transmission reach from 40 to 100 km. A digital Volterra filter at the receiver side is used to mitigate the nonlinear distortions. We obtain an average bit error ratio (BER) of 1.5 × 10(-3) for 2 × 56 Gb/s PAM-4 signal after 100 km SSMF transmission at the optimal input power, which is below the 7% forward error correction (FEC) threshold (3.8 × 10(-3)).
authors.forename: Shiwei
authors.initials: S
authors.lastname: Zhou
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.forename: Lilin
authors.initials: L
authors.lastname: Yi
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.forename: Songnian
authors.initials: S
authors.lastname: Fu