Optical nonlinearity mitigation of 6 χ 10 GBd polarization-division multiplexing 16 QAM signals in a field-installed transmission link

We report nonlinear impairment mitigation of PDM 16 QAM WDM signals through mid-link optical phase conjugation in a 834km-long installed fiber link. Efficient reuse of signal bandwidth and Q-factor improvements of up to 3 dB are demonstrated.