Comparison study of Distributed Raman Amplifier gain characteristics on CWDM band by employing SMF, NZDF, DCF, & DSF based on numerical simulation

On this preliminary work we employ distributed raman amplifier with pumping schemes are forward- & backward pumping on SMF. The model of simulation and analysis used are multiple-pump interactions on CWDM band. We used four level configuration of pumps on wavelengths; 1435 nm, 1445 nm, 1455 nm and 1465 nm with the range of tuneable power levels are 300 mWatt - 400 mWatt each ones. The average results of Stokes gain measured at L = 0 km and L = 40 km are 17.875 B and -3.5 dB respectively while the noise figure is at the range of 3 dB - 2.5 dB. The maximum length of fiber are reach at L = ~50 km. Two factors found that could decreasing the performances of distributed Raman amplifier are amplified spontaneous scattering (ASS) and Rayleigh backscattering effects. Finally the flattening gains for C band are reached successfully.