Performance optimization of different Raman amplifier configurations for improved gain using multiparameter optimization algorithm

This paper proposed three different Raman optical amplifier architectures that are designed and investigated for 50 × 100 Gbps dense wavelength division multiplexed (DWDM) system at channel spacing of 0.8 nm. The performance is determined and compared in terms of gain, gain ripple, noise figure (NF), Q-factor and bit error rate (BER) in the C-band at wavelengths in the vicinity of 1550 nm. Pump powers of the Raman amplifier are selected using multiparameter optimization algorithm to achieve maximum gain with small ripple. The effects of varying input powers on gain, gain ripple and NF are also investigated. Raman amplifier with bidirectional pumping configuration achieves highest average gain of 21.42 dB with lowest gain ripple of 1.24 dB. Average gain of 21.37 dB with gain ripple of 1.55 dB is obtained for forward pumping configuration. For backward pumping configuration, an average gain of 21.32 dB is obtained. All three configurations achieved a good quality factor (> 12.0 dB) at each wavelength. The utility of these Raman optical amplifier architectures in long-distance DWDM systems is validated by the obtained high gain, improved gain flatness, good Q-factor, and low BER.