Giga is the new Mega
Violet, blue, green, red – using light in these colours, scientists from the Photonic Communications Lab (PCL) at the Harz University of Applied Sciences have created something of a kaleidoscopic record: they have succeeded in transmitting data over 100 metres at a rate of 8.26 gigabits a second. By way of comparison, current internet tariffs promise speeds of 100 megabits a second, i.e. 0.1 gigabits, with a superfast VDSL connection. Does this mean data transmission at giga-speeds rather than mega-speeds?
It is something that everyone is familiar with: we type a word, let’s say ‘glass fibre’, into the Google search engine, press ‘Enter’
and light immediately high tails it towards the Google-Server, only to return in 0.43 seconds with something like 941,000 search results in tow – including the Wikipedia information: “Glass fibre is a material consisting of numerous extremely fine fibres of glass.” And voilà! (15,000,000 hits in 0.31 seconds): so that’s how optical data transmission works. Impressively fast, isn’t it? However the speed on the long-distance network drops appreciably over the last few metres; there, the cables, mostly made of copper, create a bottle-neck for the data, which are then carried by electric current and not by light. And that is precisely where the giga-fast polymer optical fibre (13,000 in 0.34), also known as ‘POF’, comes into play.
With it, scientists at the PCL and Professor Ulrich Fischer-Hirchert, who holds the Chair of Telecommunications in the Department of Automation and Information Studies at the Harz University of Applied Sciences, have achieved a world-record for data transmission (64,400 in 0.21). They managed this by passing light, fed by four laser diodes (for colours: see above) over a so-called ‘multiplexer’ , which mixed the multi-coloured stream of light into white light, which was then carried on its way by a single polymer fibre. At the end of the conductor there was no search-machine server but a ‘de-multiplexer’, which split the white light into its components again, in order to be able to read off the signal it carried.
According to one of the people involved in the project, Dr. Matthias Haupt, the polymer fibres have, apart from their resistance to dust and dirt, one further crucial advantage over the short distance, in comparison to copper wires: “The light transmitted using a POF is not subject to interference either from other light sources or from electro-magnetic sources – nor can it disturb anyone else,” says Haupt. That, he claims, is one reason why polymer optical fibres are being used to transmit data in motor vehicles – from the smallest Smart to the huge Maybach: by using them, the data stream can be run through the mass of cable in the wiring harness – Moreover, polymer optical fibres (“NSA”, 76,700,000 in 0.18 – now that was quick….), he claims, are immune to being tapped. Fischer-Hirchert and Haupt want to take the research further, and to break the ten-gigabits barrier of over 100 metres. They are sure that, with (even) higher data transfer speeds, they will be able to find a broad palette of new areas of application for these ‘superfast fibres’, including high-resolution TV (8k beckons) and data transmission in planes and trains, as well as logistics and factory automation.
In a world where everything happens at lightning speeds, it occurs to us – we must quickly pop down to the shops to buy those last few Christmas presents (never mind about megabits) – I know, I know…… we’ve left it too late, but that does not stop us wishing all the readers of our blog a happy holiday and a good start to 2015 – an exciting year in which another Techtextil will be taking place.
Picture above: All lit up like a Christmas tree: components of the POF link for splitting and re-combining data streams, manufactured using spray-casting technology.
Source: PCL/HS Harz