Multi-Band ESCL Transmission Supported by Bismuth-Doped and Raman Fiber Amplification

Ultra-wideband transmission utilizesbandwidths beyond the standard C-band to enable significant network capacity upgrades. Upgrading the standard C-band to a C+L-band transmission scenario is already feasible, and exploratory transmission is being performed in the S-, E-, and O-bands to investigate quality of transmission (QoT) impairments in these spectral regions. In this article, experimental transmission through a SCL- and partial E-band spectral region is performed, with use of a hybrid amplifier that exploits discrete Raman amplification for the SCL-bands, and a bismuth-doped fiber amplifier (BDFA) for the E-band. Through this transmission bandwidth, we demonstrate that 36 Tbit/s transmission is possible, with 150 coherent channels over 70 km of standard, single-mode fiber. This result is compared to a wideband physical layer model that considers a realistic full spectral load transmission scenario, where the E-band is occupied by 74 channels, providing a total of 221 channels. This comparison demonstrates that, for both scenarios in this experiment, the greatest impairment is present within the S-band, and the addition of the E-band to a SCL-band scenario has a negligible impact upon the QoT within the C- and L-bands.