Phase-sensitive amplifier link with distributed Raman amplification.

We demonstrate long-haul transmission using a hybrid amplifier approach combining distributed Raman amplification and lumped phase-sensitive amplification. Aside from the well-known resulting SNR improvement, distributed Raman amplification is included in an effort to improve the nonlinearity mitigation capability of the phase-sensitive amplifiers. When changing from phase-insensitive operation to phase-sensitive operation in a link employing distributed Raman amplification, the transmission reach at BER = 10 is increased from 15 to 44 spans of length 81 km while simultaneously increasing the optimal launch power by 2 dB.