title: Design of double-pass discrete Raman amplifier and the impairments induced by Rayleigh backscattering.
abstract: We report on the investigation of discrete Raman fiber amplifier in double-pass configuration based on the dispersion-compensated fiber and high reflection FBG. We proved in simulation and experiments that the double-pass configuration requires nearly 50% less pump power and the same fiber length to provide the same Raman gain and double-dispersion-compensation performance compared to the typical counter-pumped Raman amplifier. We also analyzed the equivalent noise figure (NF) and the Rayleigh backscattering impairments. The theoretical results shown that the impact of multipath interference (MPI) noise is the dominating limitation factor of this system operated at very high Raman gain region.
authors.forename: M
authors.initials: M
authors.lastname: Tang
authors.forename: P
authors.initials: P
authors.lastname: Shum
authors.forename: Y
authors.initials: Y
authors.lastname: Gong