1800 km 16QAM transmission with a 400G QSFP-DD coherent pluggable

We demonstrate real-time long-haul transmission with 400G digital subcarrier-multiplexed QSFP-DD coherent pluggable in a live production network, achieving a record post-FEC-error-free reach of 1800-km with 400G-16QAM, 80% longer than all previously publicly announced records.