High speed duobinary modulation in hybrid DWDM with Raman-EDFA hybrid amplifier

Abstract

The high speed duobinary modulated signal is tested on the 16×40Gbps DWDM-OTDM hybrid system with Hybrid Optical Amplifier (HOA): Raman and Erbium Doped Fiber Amplifier (Raman-EDFA). It is shown that when 640Gbps high speed duo binary signals are transmitted using HOA, it covers maximum single span of 119km of Pumped Single Mode Fiber (PSMF) with Maximum Nonlinear Duo Binary Limit (MDNL) = 6dBm after which the output rapidly falls to unacceptable levels. An overall gain of > 11 dB is reported for HOA and acceptable output power and signal quality with Q factor >18dB is reported. Further the duo binary hybrid system performance is compared with the standard binary transmission system and the proposed system is compared with current state-of-the art schemes.