Optical Layer Impairments and Their Mitigation in C+L+S+E+O Multi-Band Optical Networks With G.652 and Loss-Minimized G.654 Fibers

The combination of multi-band optical transmission and ITU-T G.654 loss-minimized large-effective-area fibers enables superior network performance in the low-loss C+L wavelength bands. As the maximum cut-off wavelength of the G.654 fiber is increased to 1530 nm, from 1260 nm in the commonly used G.652 fiber, the multi-path interference (MPI) resulting from the interplay between the fundamental LP01 mode and the high-order LP11 mode needs to be considered when expanding the multi-band transmission window to cover the S+E+O bands. In this paper, we study optical layer impairments such as the LP01-LP11 mode coupling induced MPI in G.654 fiber, the negative impact of the stimulated Raman scattering (SRS) on the use of optical supervisory channel (OSC) and optical time domain reflectometer (OTDR) in all fiber types, and the four-wave-mixing (FWM) issue in the O-band transmission over G.652 fiber, and discuss the corresponding mitigation techniques. Extensive measurements of G.654.E fibers are made to evaluate the MPI. For impact of MPI, we include it, along with the nonlinear interference, in the generalized Gaussian noise model to accurately assess the link performance, and mitigation strategies are discussed. Additional considerations of diverse optical link conditions on amplification schemes, link distances, and cost constraints are made for provisioning C+L+S+E+O multi-band optical networks with the combined use of both G.652 and G.654 fibers, aiming for the optimal utilization of the multi-band transmission in future ultrahigh-capacity optical networks for a wide variety of applications.