Co-propagating distributed Raman amplifier utilizing incoherent pumping

We have developed a semiconductor optical amplifier (SOA) based incoherent light source for a co-propagating distributed Raman amplifier. By utilizing the incoherent light source as a 1st-order pump of the Raman amplifier, we have experimentally verified the reduction of RIN transfer regardless of the presence of simultaneous amplification by 2nd-order coherent pumps. In addition, improved Q-factor has been demonstrated by 22.5 Gbaud polarization-division multiplexing 16 quadrature amplitude modulation (PDM-16QAM) transmission experiment over 2720 km in a re-circulating fiber loop. From subsequent experimental study, we have redesigned wavelength shifted 1st-order incoherent pump and measured at Raman gains in L-band wavelength.