99.35 Tb/s Ultra-wideband Unrepeated Transmission Over 257 km Using Semiconductor Optical Amplifiers and Distributed Raman Amplification

In optical fiber networks, unrepeated links are cost effective solutions to provide connectivity in challenging contexts that hinder the deployment of in-line amplifiers. Extending the optical bandwidth beyond the C-band with ultra-wideband (UWB) amplification schemes is a promising way to scale the wavelength division multiplexed (WDM) throughput of such single-span systems. In this paper, we report on the use of semiconductor optical amplifiers (SOAs) combined with distributed Raman pumping to enable 100 nm ultra-wideband unrepeated transmissions over a 257.5 km ultra low-loss, large effective area fiber span. Leveraging state-of-the-art digital signal processing, wavelength-adaptive modulation and soft-decision forward error correction (FEC) schemes, we demonstrate a record capacity-distance product of 25.6 Pb/s
$\cdot$
km, with a net throughput of 99.35 Tb/s over 257.5 km, using 247×49 GBd channels in S-, C- and L-bands.