InP CDM and ICR Enabled 128Gbaud/ DP-16QAM-PS and 120Gbaud/DP-QPSK Long-Haul Transmission

We experimentally demonstrated record rOSNR performance for both 400 Gb/s and 800 Gb/s transmissions over EDFA-only 1500 and 1000 km SSMF, respectively, by using ≥64 GHz 3 dB bandwidth InP coherent driver modulator (CDM) and intradyne coherent receiver (ICR). At 400 Gb/s via 120 Gbaud/DP-QPSK, a 16.1 dB back-to-back (BtB) rOSNR at the 15% oFEC BER threshold of 2e-2 and a large 6.9 dB OSNR margin after 1500 km can be achieved. At 800 Gb/s via 120 Gbaud/DP-16QAM, a BtB rOSNR of 25 dB and an rOSNR after 800 km of 25.8 dB can be achieved. We also observed that by employing probabilistic shaping (PS) with 128Gbaud/DP-16QAM-PS, the BtB rOSNR performance can be further improved by 1.6 dB at a cost of a 1.7 dB lower transmitter output power as compared to those of uniformly-distributed 16QAM. As a result, a 24.3 dB rOSNR and a superior OSNR margin of 2.4 dB after 1000 km transmission can be achieved. The demonstrated state-of-art bandwidth × distance performance by using practically implementable InP CDM and ICR shows a promising solution for future line-cards and pluggable modules in long-haul transmission systems.