High-Capacity Fiber Field Trial Using Terabit/s All-Optical OFDM Superchannels With DP-QPSK and DP-8QAM/DP-QPSK Modulation

We report the results of two separate field trials aimed to achieve high fiber capacity over long-haul distances. In the first trial, 22 all-optical orthogonal frequency-division multiplexing superchannels with hybrid dual-polarization 8 quadrature amplitude modulation and dual-polarization quadrature phase-shift-keying (DP-QPSK) modulation were generated using a novel flexible format superchannel transmitter design. The signal carrying net 21.7 Tb/s data was transmitted over 1503 km of dispersion uncompensated field-installed standard single-mode fiber with the aid of hybrid Raman and erbium-doped fiber amplifier (EDFA) amplification and digital coherent detection. In the second trial, we extended the transmission distance to over 2531 km of field fiber using only EDFA for loss compensation. The increase in reach was achieved by reducing the net total data rate to 16.2 Tb/s and modulating the optical superchannel subcarriers with DP-QPSK only. To the best of our knowledge, we achieved the highest capacity field trial record to date at 21.7 Tb/s in the first trial, while the achieved capacity-distance product of 40.9 Pb/s ·km in the second trial is also the highest reported to date.