G.fast standard makes copper all fiber optical-y
The ITU has standardised G.fast, a broadband technology capable of achieving download speeds of up to 1Gbps over copper telephone wire.
While the rest of the world talks about a move to a higher fibre diet, there is still a lot of copper based phone networks out there which need to get a better broadband speed. To deal with this are suggested changes to the broadband standards on copper including VDSL2 and G.fast.
The standardisation of G.fast started in 2011, and has reached what is known as first-stage approval or consent. This means that it could become a standard by April next year, according to the ITU.
G.fast increases the bandwidth by using more spectrum. This is like putting on clip on lanes to the M25 on the busy stretches. G.fast will use the 106MHz of spectrum, which compares to the 17MHz or 30MHz used by VDSL2 and the 40MHz used by the fastest LTE-Advanced networks currently being tested.
The only problem is that G.fast only works over short distances, so 1Gbps will only be possible at distances of up to about 100 metres.
G.fast is affected by crosstalk interference, which has to be countered with vectoring. It works by continuously analysing the noise conditions on copper lines, and then creates a new, antinoise signal to cancel it out.