Fujitsu and KDDI Research announced that they have successfully developed a large-capacity multiband wavelength multiplexing transmission technology using installed optical fibers.
The two companies have developed a technology that enables transmission of wavelength bands other than the C band, which has not been used in medium- and long-distance commercial optical communications, using a batch wavelength conversion and multiband amplification technology. The optical fiber communications network introduced with this technology enables wavelength transmission at 5.2 times the wavelength multiplicity of current commercial optical transmission technology. This enables the use of installed optical fiber facilities to increase communication traffic in a cost-effective and labor-efficient manner. The technology makes it easier to expand the transmission capacity in urban areas and densely populated residential areas where installation can prove challenging, and offers the potential to significantly reduce the time required to start the service and reduce costs.
The development was undertaken as part of the ”Research and Development Project of the Enhanced Infrastructures for Post-5G (1) Information and Communication Systems” (2) commissioned by Japan’s New Energy and Industrial Technology Development Organization (NEDO).
Amidst growing demand for services that leverage IoT, artificial intelligence (AI), and big data analysis, NEDO aims to strengthen the development and manufacturing base of Japan's post-5G information and communications systems by developing core technologies for post-5G information and communications systems. As part of this effort, from October 2020 to October 2023, Fujitsu and KDDI Research engaged in a project to enhance the performance of post-5G optical networks. Conventional commercial optical fiber communication networks use single-mode fibers in which light passes only through the center of the optical fiber, and use the C band (wavelength band: 1,530 nm to 1,565 nm) (3) as the signal transmission band of the optical network. However, as the amount of communication traffic increases, the C band alone is expected to have insufficient transmission capacity. To increase the transmission capacity per fiber, the two companies aimed to increase the wavelength band used from the C band to the L band (1,565 nm to 1,625 nm), the S band (1,460 nm to 1,530 nm), the U band (1,625 nm to 1,675 nm), and the O band (1,260 nm to 1,360 nm), with the aim of making it multi-band.
