Investigation of real-time 128.7 Tbit/s DWDM transmission over 75 km G.654.D fiber using S + C + L 17-THz bandwidth lumped doped fiber amplifiers

Multi-band transmission (MBT) technologies, particularly the combination of S-, C-, and L-bands, offer significantly greater potential for improving the transmission capacity of optical communication systems compared with single-band or dual-band technologies. However, the adoption of S + C + L band typically faces more severe nonlinear effects (such as stimulated Raman scattering induced power transfer), immature device performance (S-band), and other issues, thus requiring more refined power management mechanisms (such as transmitter power pre-tilt, transmitter power optimization), device performance optimization (S-band optical gain and noise figure), and system end-to-end optimization (data rate, baud rate, modulation format, fiber type, etc.) We first conduct numerical simulations to evaluate the performance of the S + C + L triple-band scenario with an 18-THz spectral width, and a 144 Tbit/s transmission over 90-km optical fiber and a 120 Tbit/s transmission over 120-km fiber are performed. Then, we have further experimentally demonstrated a record real-time 128.7 Tbit/s transmission over 75 km ultra-low loss and large-effective area G.654.D fiber together with S + C + L-band 17-THz bandwidth using only lumped doped fiber amplifiers. The experimental results show that a record real-time single carrier bit rate of 1275.93 Gbit/s using digital coherent transceivers with a symbol rate up to 135 GBaud over the widened C-band with 6-THz bandwidth is successfully demonstrated.