Fujitsu and KDDI Achieve Breakthrough in Optical Fiber Transmission Technology

Fujitsu and KDDI Research have announced a significant leap in optical fiber transmission technology, unveiling a breakthrough in large-capacity multiband wavelength multiplexing.
KDDI AU store JapanLeveraging existing optical fibers, the technology enables transmission across various wavelength bands beyond the commonly utilized C band, promising a substantial increase in communication traffic.

This innovation allows for transmission at an unprecedented 5.2 times the wavelength multiplicity of current commercial optical transmission technology. By tapping into wavelength bands such as the L band, S band, U band, and O band, typically unused in medium- and long-distance commercial optical communications, this advancement offers an efficient means of boosting communication traffic using installed optical fiber facilities.

The development, part of Japan’s initiative for post-5G information and communications systems, aimed to strengthen core technologies in line with the demands for services reliant on IoT, AI, and big data analysis. Over the course of the project, Fujitsu and KDDI Research successfully expanded the spectrum of utilized wavelength bands, overcoming limitations associated with the C band’s capacity constraints.

The project resulted in the creation of a simulation model by Fujitsu, accounting for transmission performance degradation in multiband transmission. This model enabled high-precision simulations, minimizing errors and considering interactions between bands and transmission performance degradation factors.

KDDI Research’s contribution focused on leveraging the O band, previously underutilized in high-density wavelength division multiplexing (DWDM) transmission. Their research allowed for the utilization of twice the frequency bandwidth of the conventional C band in O-band transmission, achieving multiband wavelength multiplexed transmission over a considerable distance.

The established technology not only facilitates multiband dense wavelength division multiplexing (DWDM) transmission but also ensures coherent DWDM transmission in the O band, traditionally challenging due to non-linear noise effects. The method minimizes the impact of nonlinear noise, optimizing transmission even without extensive signal compensation, thereby reducing the load on digital signal processing and enhancing energy efficiency.

This breakthrough holds immense promise for revolutionizing communication infrastructure, particularly in urban and densely populated areas, where expanding transmission capacity proves challenging. The technology not only offers a cost-effective and efficient means of increasing communication traffic but also reduces service deployment time and operational costs significantly.

The successful demonstration of multiband wavelength multiplexed transmission over existing optical fibers showcases a transformative milestone in enhancing communication networks, poised to meet the escalating demands of evolving digital services.