On September 3, 2024, NTT announced that it had successfully demonstrated, for the first time in the world, long-distance optical amplification relay transmission exceeding 100 Tbps using ultra-long wavelength band (U-band) wavelength conversion technology. This foundational technology achieves more than three times the data transmission capacity compared to previous optical transmission technologies and is expected to be utilized in long-distance transmission for IOWN and 6G APNs (All-Photonics Networks) in the future.
In the demonstration experiment, a loop transmission experiment network was constructed with optical amplification relays inserted every 80 km. Using this network, optical amplification relay transmission in the 14.85 THz band was conducted, achieving a total transmission capacity of 115.3 Tbps over a distance of 800 km. This distance is the longest ever achieved in a transmission demonstration exceeding 100 Tbps. Furthermore, even at a transmission distance of 2400 km, a capacity of 72.6 Tbps was achieved, demonstrating a technology level capable of covering the entire Honshu region.
NTT stated that they will continue to enhance the reliability of communications and long-term stability as they move towards the practical application of the demonstrated technology. Additionally, they plan to further expand the bandwidth (exceeding 20 THz), including extending to the shorter wavelength side, and to increase capacity by expanding flexible wavelength resources suited to the characteristics of the entire optical fiber transmission path and system. In particular, they aim to evolve the wavelength resource expansion technology by integrating it with high-speed (multi-terabit) technology per wavelength, enabling simultaneous expansion of transmission capacity and distance.
NTT also reiterated their commitment to advancing research and development to further integrate their proprietary device technology, digital signal processing technology, and optical transmission technology, with a focus on the evolution of APNs in IOWN and 6G beyond 2030.
Source
https://release.nikkei.co.jp/attach/677803/02_202409031736.pdf