Nippon Telegraph and Telephone (NTT) has announced the development of a four-core multicore optical fiber (MCF) capable of delivering four times the data capacity of conventional fiber, while maintaining the same thickness and diameter.
The company highlighted that keeping the cable’s cross-section unchanged is essential for compatibility with existing infrastructure. This means the new fiber can be integrated into current systems, including cable-laying vessels, terrestrial interconnect setups, and terminal racks, without requiring major upgrades.
Unlike traditional single-core optical fibers, the new MCF contains four separate cores enclosed within glass cladding. Through spatial multiplexing, each core can transmit signals independently, allowing a single fiber to carry four simultaneous optical data streams.
In large-scale applications such as undersea cables, which typically bundle up to 48 fibers, the technology significantly boosts capacity. A single cable could support up to 192 cores, dramatically increasing data transmission potential.
To enable practical deployment, NTT has also developed supporting components, including a submarine joint box for connecting conventional terrestrial fibers to the new multicore system, an MCF cable terminal compatible with existing transmission equipment, and a factory joint box for linking multicore cables on the seabed.
The company expects the technology to be ready for deployment by 2029. Once implemented, it could allow telecom operators to expand network capacity more efficiently, reducing both costs and the need for large-scale infrastructure changes.
