Fujitsu develops cost-effective optical architecture for 400 Gbps transmission

Source: Fujitsu. A metropolitan area data centre network in a distributed computing implementation. 

Fujitsu Laboratories and Fujitsu R&D Center (collectively Fujitsu) have developed a basic architecture for digital-signal processing in optical transceivers that can transmit data at 400 gigabits per second over a single wavelength. The technology would allow multiple data centres within a metropolitan area to be connected at high capacity yet low cost.

According to Fujitsu, achieving 400 Gbps per wavelength had previously required the use of expensive, specialised components for the best results. The price of components for optical transceivers may be brought down by using cheaper parts or by using CMOS technology or silicon photonics technology, which are being developed in parallel, but all three methods currently offer relatively poor performance today. Due to piece-to-piece performance variations of the components, economically transmitting over distances of roughly 100 km, the distance needed for communications between data centres, had not been possible using current methods. 

Fujitsu has developed new transceiver architecture in which a specially designed reference signal can be transmitted and received without the distortion that would usually make signals sent over such distances useless. Fujitsu has successfully performed repeaterless transmission tests over a distance of 160 km. This technology accurately compensates for variations in the characteristics of transceiver components and distortions introduced in the transmission path, making it possible to communicate at 400 Gbps per wavelength using inexpensive optical transceiver components.

This technology can be applied to integrated optical transceiver components using silicon photonics, a technology expected to reduce costs and contribute to building next-generation distributed computing platforms that will support 5G mobile networking and diverse Internet of Things (IoT) services.

Fujitsu Laboratories plans to continue testing the technology combined with silicon photonics technology, and aims to have a practical implementation of a 400 Gbps transceiver in 2019.