RIN Mitigation and Transmission Performance Enhancement With Forward Broadband Pump

We demonstrate that using a broadband, first order, and coherent pump laser enables effective and efficient forward-pumped distributed Raman amplification for long-haul transmission systems, thanks to the simultaneous suppression of ASE noise and RIN-related penalty. We show in both experiments and simulation that this scheme extends the reach of 10 × 120 Gb/s DP-QPSK WDM transmission by a minimum of 50%, compared with low RIN Bi-doped fibre laser and other commercially available pump lasers. Moreover, it requires very low forward pump power, and maintains uniform/symmetric signal power distribution which allows effective nonlinearity compensation.