Optimized amplification scheme in unrepeated DWDM system over 325 KM G.652 fiber

This paper reports a 325-km ultra-long span repeater-less transmission system in a 17×10 Gbit/s optical transmission system by using different amplification schemes. We demonstrate two different amplification schemes which combine Erbium doped fiber amplifier (EDFA), Raman amplifier or combined EDFA and remotely pumped optical amplifier (ROPA). The amplification schemes are tested and compared, and the power budget of 72 dB by using the EDFA/ROPA scheme is obtained.