EXTENDING TRANSMISSION DISTANCE OF HIGH-DENSITY WDM SYSTEMS USING POST TRANSMITTER FIBER RAMAN AMPLIFIERS

Abstract

We investigate the behavior of the multichannel signals in a high-density WDM system with the consideration of stimulated Raman scattering. We provide a parameter to evaluate the depth of Raman crosstalk and analyze the transmission distance limitation imposed by Raman crosstalk. To extend the system transmission distance, a post transmitter fiber Raman amplifier is employed. The allocation of signal channels on the pump gain profile is discussed. We found that there exists an optimum pump power which results in a maximum amplifier gain. The example shows that the transmission distance limitation imposed by Raman crosstalk can be extended by 20 km for a 30-channel system with 0.25-dB/km fiber loss.