Could ultrafast broadband over copper speed the rollout of gigabit internet?

Researchers in the UK have revealed a technique that could enable up to one gigabit internet speeds over existing copper connections.

For the most bandwidth hungry users fibre optic cable tends to be the best option; but as most UK consumers and small businesses are still on the old-style copper phone lines they're forced to languish in the broadband slow lane.

Now researchers claim to have demonstrated speeds approaching those seen over fibre optic - but without the hassle and expense of having to connect fibre to the premises, using instead a combination of fibre and copper.

The team from BT's Adastral Park R&D centre in Ipswich have released trial results that show combined downstream and upstream speeds of up to one gigabit per second (1000 Mbps) being delivered over a mix of fibre and copper connections.

The Fibre To The Distribution Point (FTTdp) G.FAST technology is being designed to deliver these speeds to homes and business by rolling fibre to telephone poles or junction boxes and then relaying data over existing copper links.

During the G.FAST trials, downstream speeds of around 800Mbps were achieved over a 19m length of copper, combined with upstream speeds of more than 200Mbps. Speeds of around 700/200Mbps were also achieved over longer lines of 66m, which encompasses around 80 per cent of such connections in the UK.

BT's fibre network - which is being rolled out by its local access network business Openreach - currently passes more than 20 million UK premises using a mix of Fibre to the Premises (FTTP) and Fibre to the Cabinet (FTTC) technology .

FTTC delivers speeds of around 80 Mbps and is easier to install than FTTP, so is the slower, but more common of the two technologies.

FTTdp falls somewhere between FTTC and FTTP, requiring the fibre to be laid closer to the premises than under FTTC, as FTTdp needs a shorter copper link, but delivering speeds approaching FTTP. G.FAST technology uses much higher frequencies than FFTC, plus advanced 'crosstalk' cancellation techniques, to make ultrafast speeds possible.

As well as FTTdp being simpler for the telecoms operator to install, BT says the technology could be a "self-install" product with no need for home engineering visits to set it up.

Over the coming months BT researchers will use a new laboratory at Adastral Park to study the technical capabilities of G.FAST hardware designed by system vendors such as Adtran, Alcatel Lucent and Huawei.

Dr Tim Whitley, MD of Research and Innovation at BT Group said: "We see G.FAST as a very promising technology with significant potential - that's why we're putting some of our best minds on the case to assess it fully in a purpose-built facility."

Deployment of the technology to customers is likely years away, with complications involving the need to standardise technologies needed for G.FAST, the requirement for telecoms operators to install new equipment to enable these connections and questions about how this equipment would work alongside that serving existing superfast broadband links.