Latest Long-Distance Optical Cable Models

The latest long-distance optical cables use multicore fibers, with 19-core designs achieving over 1 petabit per second across nearly 1,800 kilometers.Multicore Optical FibersRecent advancements focus on multicore optical fibers, which contain multiple cores within a single fiber to drastically increase data capacity without enlarging the cable diameter. NEC and NTT have successfully demonstrated 12-core optical fibers for long-distance submarine and terrestrial transmission, achieving stable high-capacity transmission over 7,280 km in submarine experiments and over 1,017 km on land, with field capacities up to 455 terabits per second using large-scale MIMO signal processing to manage inter-core interference and crosstalk .19-Core Optical Fiber BreakthroughThe most recent milestone involves a 19-core optical fiber, equivalent to 19 standard fibers, which achieved 1.02 petabits per second over 1,808 kilometers. This fiber maintains a standard 0.125 mm cladding diameter, compatible with existing infrastructure, and incorporates low-loss performance across multiple wavelength bands. The experiment also used an optical amplification relay system to extend the transmission distance while maintaining high capacity, setting a new world record for long-distance optical communication .Key TechnologiesSpatial Division Multiplexing (SDM): Enables multiple cores to transmit data simultaneously, increasing total capacity.Large-scale MIMO Processing: Separates signals from coupled cores to mitigate crosstalk and interference.Optical Amplification: Boosts signal strength over long distances, essential for maintaining high-speed transmission.Probabilistic Constellation Shaping (PCS): Optimizes signal distribution to approach the Shannon limit, improving efficiency in pluggable modules .Applications and ImplicationsThese innovations are critical for submarine cables, terrestrial backbone networks, and inter-data center links, supporting the exponential growth of data traffic driven by AI, 5G, and cloud services. The combination of multicore fibers and advanced signal processing allows for higher capacity, longer distances, and more efficient deployment, reducing the need for multiple parallel cables and lowering operational costs . In summary, the latest long-distance optical cables leverage multicore fiber designs, advanced signal processing, and optical amplification to achieve unprecedented data rates and distances, marking a significant step toward future high-capacity global communication networks.