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Multicore fiber transmission over transoceanic distances

We investigate the application of space division multiplexing (SDM) technology to a long haul undersea transmission using multi-core fiber (MCF). We discuss two experimental demonstrations conducted with a 12-core fiber. The first study shows that SDM can help to achieve simultaneous improvement of power efficiency and capacity of long-haul transmission. Using SDM, power efficient optical system design and modulation format with high receiver sensitivity we demonstrate 105.1 Tb/s transmission over 14,350 km with pump power per 12 EDFAs equivalent to a single 800 mW 980 nm pump laser. In the second study, we investigated capacity limits of transoceanic transmission achievable with MCF and extended C and L bandwidth of optical amplification. The study shows 520 Tb/s potential transmission capacity over 8,830 km using 9 THz of optical bandwidth. To achieve this capacity, we also used new coded modulation with 1.0 dB sensitivity improvement compared to 8QAM with the same SE of 4.86 b/s/Hz.