2019 Volume 8 Issue 5 Pages 166-171
We demonstrate 2nd-order forward-pumped distributed Raman amplification (DRA) in PDM-16QAM 25-GHz-spaced 11-channel WDM transmission system in L-band. Our forward-pumped DRA consists of semiconductor-optical-amplifier-based incoherent light source for signal amplification and two coherent light sources for incoherent light amplification. After 1,760 km single-mode-fiber transmission, 1.2-dB Q-improvement is experimentally achieved by our DRA scheme compared with that of in the case of amplification with EDFA only. And we also show the low RIN-transfer-induced Q-penalty of our pumping scheme at the Raman on/off gain of up to 10 dB.