Posted: 01st Sep, 2011 By: MarkJ
The Communications Regulator, Ofcom UK, has today announced that it is officially moving forward with plans for the introduction of licence exempt
White Space wireless broadband technology in the UK. This uses the radio spectrum that exists between digital terrestrial TV channels to deliver internet access over a
Wireless Regional Area Network (WRAN);
IEEE 802.22 standard (
details).
In principal such a technology would have many advantages. Related services typically exist between the lower
470MHz and
790MHz frequencies, which travel further and more easily through walls. Each TV channel is given a slice of this spectrum and a small gap (the white space) is then left between the channels to limit the potential for interference.
Ofcom's Chief Executive, Ed Richards, said:
"At an early stage Ofcom identified the potential of White Spaces, which are currently lying vacant all around us.
Within Europe, we have been leading the way to try to harness this capacity without causing harmful interference to existing users of the spectrum.
The solution we have devised creates the opportunity to maximise the efficient use of spectrum and open the door to the development of a new and exciting range of consumer and business applications."
A number of trials are currently underway in the UK (
here and
here) and are already showing some promising results. However the technology, which appears to work like Wi-Fi, is still very complicated to get right.
The primary problem is that White Space routers (connectivity hardware) would first need to consult a
frequency database hosted online. Digital TV channels often swap frequencies and failing to use the correct ones could result in interference, thus it's necessary to keep an up-to-date and locally aware database.
Ofcom has decided to allow multiple third-party providers to develop databases, which it believes will create a competitive marketplace and incentivise operators to provide the best database service to consumers.
Download speeds of up to
22Mbps per channel could be possible by using this technology, although that would be shared (contended) with other users. Never the less it could prove to be a lifesaver for isolate towns and villages.
The regulator now expects to consult on a
Draft Statutory Instrument for making white space devices licence exempt. The technology itself could be
launched in the UK during 2013.
UPDATE 2nd September 2011We've just had a new comment come in from Wi-Fi Provider Xirrus.
Perry Correll, Director of Product Marketing at WiFi Provider Xirrus, said:"The wired to wireless evolution of the client has also resulted in the evolution of wireless technologies. Wi-Fi has evolved to 11n with 11ac and 11ad in the works, mobile phones to 3G to 4G. Now Whitespace (802.11af, 802.22, 802.16h, a.k.a. Super Wi-Fi) is emerging as an exciting technology too. As mentioned in the article, Whitespace takes advantage of newly available frequencies resulting from changes in the Broadcast Television spectrum. Although whitespace will not challenge Wi-Fi for bandwidth levels, its lower frequencies does allow it to travel far greater distances as well as significantly improved propagation through indoor obstructions (brick, concrete, etc). The result is Whitespace has real potential advantages for both outdoor and indoor environments, allowing a single wireless technology to have a role in providing Mobile Phone, Broadband and LAN connectivity services, something eluding other technologies to this point.
Today most users do not care what technology is used by their clients to make the connection, they just want connectivity. Whitespace offers an additional capability and as ‘cognitive’ wireless devices emerge over the coming years, these devices will be able to support different technologies that will allow them to support different client requirements in various RF environments. Clients can now connect at longer distances with whitespace (at lower data rates) and as they reduce the distance to the Access Device, they can then be connected to higher data rate technologies (i.e. Wi-Fi) within the same device. This allows the client to improve performance without severing connectivity or losing an active session."
It's important to remember that Wi-Fi itself remains a completely separate, but similar, solution to White Space technology.