A new speed record for optical fibres

Close-up of fiber optic cables

New multiple-core fibres will allow transmission speeds unconceivable until now, even if currently outside the present standard commercial homologations.

It seems that universities and research centres are competing to win the record of the fastest optical fibre connection in the world. The ultrafast target is not an end in itself, representing especially the result of researches about new methodologies to speed up optical nets. Currently the DTU (Technical University of Denmark) ranks at the top, having reached 43 terabits per second (5,375 gigabytes, if you prefer) on a single optical fibre and on a single laser transmitter: just to give an idea, the transfer of the entire 1TB hard drive content in a fifth of a second. The previous record, in 2011, was attained by the Technology Institute of Karlsruhe, which had achieved 26 terabits. The value of the result reached by Danish researchers is undoubtedly in the numerical value of the data rate, but also and especially in the fact that the 43 terabits have been obtained by using a single fibre. In fact, hundreds or even thousands of terabits (petabits) have already been reached several times by other research centres, both academic and in collaboration with sector companies, but the value of these results is diminished by the fact that the experimental connection was constituted by multiple fibres with multiple independent laser sources as well, resulting in a cumulative value that, even if notable, is based on a net implementation that does not correspond to the real commercial requirements of an optical fibre connection. The technological solutions adopted by Danish researchers are not completely known, yet, even if they have used as basis a multicolour fibre, even if with a single laser, that is to say a single glass filament but with seven multiple channels, each of which can convey its optical signal. Besides, this outstanding technological novelty, implemented by the Japanese company NTT, was not available in 2011, at the time of Karlsruhe record, achieved instead with single core fibre. Other detail, the use of multiplexing SDM and WDM techniques (Spatial/Wavelength Division Multiplexing), to avoid the collisions among signals. It is worth highlighting that currently the fastest available commercial connection single-laser-single-fibre is 100 Gbps Ethernet, and IEEE, organization that defines Ethernet specifications, is working at the definition of 400 Gbps and 1 Tbps version, whose sanction is foreseen in 2017.



Wire Tech World © 2024 All Rights Reserved