Submarine transmission systems using digital nonlinear compensation and adaptive rate forward error correction

We report on a full C+L-band erbium-doped fiber amplified (EDFA) submarine transmission experiment of 178 wavelength-division multiplexed channels of 49-GBd polarization multiplexed 16QAM signals, achieving 54.2 Tb/s after 6600 km, with a record per-channel average net bit rate of 304.5 Gb/s. Digital backpropagation and time-domain perturbative nonlinearity compensation were alternatively applied to all channels and their respective benefits, in terms of throughput increase, reach increase, and complexity, were addressed. Multiple-rate spatially coupled low density parity check forward error correction codes with a novel rate optimization algorithm were employed. The power consumption of the power feeding equipment of our EDFA-only amplification scheme was analyzed and compared with that of hybrid EDFA Raman amplification. We also provided numerical and theoretical performance analysis of nonlinear uncompensated/ compensated systems.