Trial transmission routes 38.4 Tbps traffic over 762-km fibre path

June 30, 2015 // By Graham Prophet
Socionext’s latest generation of ultra high-speed digital-to-analogue (DAC) and analogue-to-digital (ADC) converters, featuring sampling rates up to 92 Gsamples/sec and high analogue bandwidth, have been integrated into coherent receivers and transmitters that were used in a recent record-breaking field trial in France.

Socionext – the enterprise that was formerly the high-performance SoC and ASIC arm of Fujitsu – provided its high-speed conversion SoCs as part of the record-breaking transmission field trial. For the first time, several tens of terabits per second have been transported over a 762-km fibre optic link – Lyon-Marseille-Lyon – in the Orange (France) optical transport network.

Socionext was part of a team of engineers from Orange, Coriant, Ekinops and Keopsys who successfully demonstrated the highest ever C-band transmission capacity using 24 x 1 Tbps/DP-16 QAM (i.e. 24 Tbps), 32 x 1 Tbps /DP-32 QAM (i.e. 32 Tbps) and 32 x 1.2 Tbps/DP-64 QAM (i.e. 38.4 Tbps) modulation formats in a ‘live’ networking environment. A record-setting transmission reach of 762 km in the same ‘live’ environment was achieved, which is more than twice the distance of any previous field records for 32 QAM, and the first ever regional transmission for 64 QAM. These achievements represent an important milestone in the research and development of highly scalable, spectrally-efficient optical networking technologies for future network growth.

As part of ongoing technology collaboration, Socionext provided key technology and components, in the form of development kits, to enable partners [to carry out] the evaluation and optimisation of higher-order modulation techniques and next-generation algorithms. The new generation of transmitters and receivers used to establish the transmission record were based on ultra high speed DACs and ADCs designed and developed by Socionext’s Network SoC Business Unit using a standard 28 nm CMOS technology. The converters cover a broad sampling range with a maximum rate of 92 Gsamples/sec. High effective resolution and analogue bandwidth characteristics, greater than 20 GHz, makes possible scalable architectures for multiple wavelengths and high modulation formats on a single device. On-chip implementation of the converters using advanced packaging technologies along with very low power consumption are additional features that are mandatory for future long-haul, metro and access applications.

“We are excited