Comparison of S-Band Doped Fiber Amplifier and Raman Amplifiers in Long-Haul Coherent Transmission

We compare the long-haul coherent transmission performance of 30 GBaud DP-16-QAM WDM signals using five different S-band optical amplifiers: a thulium doped fiber amplifier (TDFA), a distributed Raman amplifier (DRA) and three different lumped Raman amplifiers (LRAs) using 10 km inverse dispersion fiber (IDF), 10 km, and 5 km Raman optical fibers (ROFs). Over 1050 km standard single-mode fiber (SSMF), the DRA performed the best with an SNR of 14.2 dB at the optimum launch power of −2.3 dBm, followed by the TDFA with an SNR of 13.0 dB and the LRA using 10 km IDF with 11.6 dB of SNR.