Performance comparison of an 80-km-per-span EDFA system and a 160-km hut-skipped all-Raman system over standard single-mode fiber

In this paper, we present a comprehensive comparison of the performance of an 80-km-per-span erbium-doped fiber amplifier (EDFA) system and a hut-skipped (160-km-per-span) all-Raman system over standard single-mode fiber (SSMF) for the first time, using semianalytic models. The numerical results reveal that a hut-skipped all-Raman system (using one-order Raman pumping) can achieve comparable performance as the conventional 80-km-per-span EDFA system for a common 50-GHz-spaced 80 times 10 Gb/s nonreturn-to-zero (NRZ) wavelength division multiplexing (WDM) system at typical fiber loss of 0.22 dB/km. For 100-GHz-spaced 40 times 40 Gb/s carrier-suppressed return-to-zero (CS-RZ) WDM transmission, it was found that a hut-skipped all-Raman system can achieve even better performance than the current 80-km-per-span EDFA system. It was also found that the impact of pattern-dependent Raman crosstalk is more severe than interchannel cross-phase modulation (XPM) in a hut-skipped all-Raman system with 80 times 10 Gb/s capacity