Alexey Turukhin

Power-Efficient 100 Gb/s Transmission Over Transoceanic System

The capacity of optical communication systems can be continuously scaled by utilizing spatial division multiplexing (SDM) technology. However, this scaling has significant impact on the required optical and electrical power as the number of EDFAs increase. This constraint is crucial in long-haul undersea optical systems where electrical power for the entire system is fed from the landing points. Successful implementation of SDM in undersea systems will require both signal modulation and amplification technologies with high power efficiency. In this work, we use 8-D coded modulation and simple EDFA design to demonstrate 100 Gb/s transmission over 9750 km with record high power efficiency as defined by the ratio of capacity-distance product to the total amplifier output power.

SDM for Power-Efficient Undersea Transmission

We discuss space division multiplexing as a means of increasing link capacity for power limited transmission in undersea communication. Theoretical study of erbium-doped fiber amplifiers-based space division multiplexing (SDM) transmission shows the existence of optimal values of spectral efficiency, signal-to-noise ratio, and span length that maximize power efficiency. We experimentally confirm the existence of an optimal spectral efficiency and demonstrate power efficient SDM transmission using 12-core multicore fiber. Modulation format, amplifier, and link design are discussed in connection to SDM power efficient transmission.

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.

Maximum Optical Power Efficiency in SDM-Based Optical Communication Systems

We demonstrate the existence of an optimal spectral efficiency that maximizes the power efficiency and/or capacity of a power limited erbium-doped fiber amplifier (EDFA)-based space division multiplexing transmission system. Optimal spectral efficiency observed experimentally is in good agreement with a theoretical estimate.