NTT Corporation and Hokkaido University have developed a revolutionary multi-core and multi-mode optical fiber design that boosts transmission capacity by a factor of 10. The breakthrough, presented at the European Conference on Optical Communication (ECOC) in Frankfurt this September, combines spatial multiplexing and coupling in a structure that maintains the same outer diameter as current fibers. This innovation supports the IOWN initiative’s goal of achieving a 125-fold increase in transmission capacity.
The research successfully demonstrated the world’s first optical coupling between multiple cores and modes using a three-core structure. By strategically spacing the cores and leveraging natural fiber bending, the design ensures minimal propagation delay differences, enabling reliable high-capacity transmission. A prototype fiber with seven cores, each capable of propagating three modes, achieved complete coupling of 21 optical signals over a 1 km span under controlled bending conditions.
The results provide a scalable path toward advanced optical infrastructure. With further refinement, this technology could address rising global demand for high-speed data networks, aligning with NTT’s roadmap for the 2030s and beyond. The project combines NTT’s engineering expertise with Hokkaido University’s analytical precision, emphasizing the importance of collaboration in tackling future connectivity challenges.
Key Points
• Demonstrated 10x transmission capacity in a single optical fiber.
• Combined multi-core and multi-mode design reduces the number of cores needed.
• Maintained fiber’s standard outer diameter for infrastructure compatibility.
• Achieved 21 optical signal couplings using a seven-core, three-mode fiber.
• Reduced propagation delay differences via optimized core spacing and bending.
“This innovation represents a leap forward in optical transmission, addressing the need for compact, high-capacity networks,” said Akira Shimada, President of NTT Corporation.
