NTT completes 400G transmission field trial

20 Mar 2015

Japan’s biggest communications service provider NTT Corporation and its NTT Communications unit, have announced the successful completion of stable transmission of 400Gbps optical signals on the group’s existing network, without adversely affecting existing 100G channels – as NTT added and removed 400G channels in the 100G-based wavelength division multiplexing (WDM) system. Further, the pair reported success in applying ‘advanced 400G digital coherent optical transmission techniques with novel world-top-level waveform distortion compensation techniques, and confirmed the high performance in 400G optical transmission’ compared to NTT’s conventional digital signal processing techniques.

NTT and NTT Com said that the additional 400Gbps channels and the existing 100Gbps channels ‘did not cause mutual degradation from the viewpoint of the transmission characteristics, and also confirmed that: ‘the addition and removal of the 400G channels in the existing 100G-based WDM system did not affect the communication performance of the other channels, although the communication performance was anticipated to degrade.’

The trial is seen as a next step toward expanding NTT’s optical communication capacity by four times to meet increasing demand for services such as high definition (HD) 4K / 8K movies or the expanding Internet of Things (IoT), as japan moves toward the opening of the Tokyo Olympics and Paralympics.