Researchers at Siemens have transmitted data over polymer optical fibre cable at around 1G bps, opening up new possibilities for the technology, including easy-to-build home networks linking PCs and high-definition TVs
"Polymer cable enables do-it-yourself installations," project manager Sebastian Randel said on Tuesday. Unlike optical fibre made from glass, "It's flexible and it's easy to cut and insert in connectors."
The cable is around one millimetre thick, doesn't break easily yet can be cut with a razor blade, according to Randel.
Although glass optical fibre, which is widely used in long-distance and local loop networks, can carry data at much higher speeds than the polymer version, it is also much thicker once wrapped in a protective shield, and breaks if bent too tightly, according to Randel. Cutting it cleanly to attach connectors or make joints requires a diamond blade, he said.
Demand for easy-to-install, low-cost home networking systems is growing as new high-speed services such as Internet Protocol television (IPTV) hit the market.
The twisted copper pair used in Ethernet networks is more of a competitor to polymer fibre in home networking because it is thinner and more flexible than glass optical fibre, Randel said. However, it's difficult to attach connectors, requiring special tools.
While wi-fi eliminates the need for cables altogether, it can't guarantee constant and robust transmission required for services such as IPTV, according to Randel.
Siemens researchers transmitted TV signals at 1008M bps over a 100 metre-long test network, without errors or flickering on the screen, he said.
Rather than transmit each bit as a pulse of light, they modulated the light signal using a technique similar to that used by Digital Subscriber Line to send signals over copper wires, allowing each pulse of light to carry several bits of information.
The overall effect was to increase the rate at which data was transmitted: Previous top speeds achieved over polymer were around 100M bps.
Randel was unable to say when a 1G bps polymer cable product would be available and what it would cost but said the Siemens research team proved that the technology works.