30-Tb/s (3×12.84-Tb/s) signal transmission over 320km using PDM 64-QAM modulation

We demonstrate three-channel WDM transmission of 12.84-Tb/s/ch polarization division multiplexed (PDM) 64-QAM over 320-km SMF-28 with hybrid amplification spans. Each 10-Tb/s superchannel comprises one hundred Nyquist DWDM subchannels in 1275-GHz spectrum occupancy, yielding a spectral efficiency of 7.9 b/s/Hz. The BER of all channels after transmission over 320 km is measured smaller than 2×10-2, the third generation FEC limit.