The world’s fastest data transmission speed has been achieved by University College London (UCL) researchers led by Dr Lidia Galdino, of UCL’s Electronic & Electrical Engineering. Working with Xtera and KDDI Research, the research team achieved a data transmission speed of 178Tbps, a speed at which it would be possible to download the entire Netflix library in less than a second.
UCL says the record, which is double the capacity of any system currently deployed in the world, was achieved by transmitting data through a much wider range of wavelengths, than is typically used in optical fibre. Current infrastructure uses a limited spectrum bandwidth of 4.5 THz, with 9THz commercial bandwidth systems entering the market, whereas the researchers used a bandwidth of 16.8 THz.
To do this, researchers combined different amplifier technologies needed to boost the signal power over this wider bandwidth and maximised speed by developing new Geometric Shaping (GS) constellations (patterns of signal combinations that make best use of the phase, brightness and polarisation properties of the light), manipulating the properties of each individual wavelength. The achievement is described in a new paper in IEEE Photonics Technology Letters.
The benefit of the technique is that it can be deployed on existing infrastructure cost-effectively, by upgrading the amplifiers located on optical fibre routes at 40-100km intervals. The researchers say upgrading an amplifier would cost £16,000 (US$ 21,000), while installing new optical fibres can, in urban areas, cost up to £450,000 (US$600,000) a kilometre.
The new record, demonstrated in a UCL lab, is a fifth faster than the previous world record held by a team in Japan. The speed is close to the theoretical limit of data transmission set out by American mathematician Claude Shannon in 1949.
Lead author Dr Lidia Galdino, a Lecturer at UCL and Royal Academy of Engineering Research Fellow, said, “While current state-of-the-art cloud data-centre interconnections are capable of transporting up to 35 terabits a second, we are working with new technologies that utilise more efficiently the existing infrastructure, making better use of optical fibre bandwidth and enabling a world record transmission rate of 178 terabits a second.” She added, “Independent of the Covid-19 crisis, internet traffic has increased exponentially over the last 10 years and this whole growth in data demand is related to the cost per bit going down. The development of new technologies is crucial to maintaining this trend towards lower costs while meeting future data rate demands that will continue to increase, with as yet unthought-of applications that will transform people’s lives.”
This work is funded by the Royal Academy of Engineering, The Royal Society Research grant, and the EPSRC programme grant TRANSNET (EP/R035342/1). The researchers are members of UCL’s Optical Networks Group and the UCL Institute of Communications & Connected Systems.
For more information, visit www.ucl.ac.uk