Feeds

Cambridge gets a white (space) wash

Industry gangs up to prove licence-free radio

High performance access to file storage

A consortium of Cambridge-based companies is to start testing white space radios in the UK, to see if they can coexist with each other, and everyone else.

The trials are permitted under a multi-site test licence issued by Ofcom, and will allow the likes of Microsoft, BT, Nokia, Samsung, Spectrum Bridge and BSkyB to set up radio links using TV channels that are locally empty.

The idea is to demonstrate how amazing such a technology is in the hope of getting Ofcom to approve national, and licence-free, use of the white spaces.

Microsoft et al would like us to think that using white space is a risk-free resource only limited by the regulator's imagination, and that the white space model of cognitive radios jumping between empty frequencies should be applied to the rest of the radio spectrum as quickly as possible, as shown in the company's promotional video.

But radios designed to find and use empty frequencies simply don't work, so white space proponents have been forced to use online databases of empty channels based on the location of the user. That means every white space access point will have to have GPS or similar built in, and be able to see the sky too; they'll also have to periodically check back with the database to see if things have changed.

The approach is fraught with technical difficulties, not least the way that radio propagation can change enormously depending on atmospheric conditions. There's also the matter of transmissions bleeding into neighbouring frequencies, which can be mitigated with good filters and clever radios, but not eliminated.

Large margins of error are supposed to avoid knocking out television transmissions, but avoiding interference with other white space users will be more difficult. Proponents of the technology love to compare white space radio with Wi-Fi, and Wi-Fi has certainly proved more robust than anticipated in sharing radio channels with nearby users - both users see a drop in speed, but are prepared to tolerate it.

And that's what the Cambridge trials are all about: to see if the radios can cope with interference generated by other white space users, as well as making sure the online database can provide accurate and timely information about the frequencies available.

Once that's proven then Ofcom can start wrestling with the question of who gets to run the database. In the USA the FCC has been trying to get a handle on that question for a year or so now, while the shortlisted companies continue flinging mud at each other: we can only hope the UK process won't be quite so pugnacious, assuming the trials prove successful. ®

High performance access to file storage

More from The Register

next story
A black box for your SUITCASE: Now your lost luggage can phone home – quite literally
Breakfast in London, lunch in NYC, and your clothes in Peru
Broadband Secretary of SHEEP sensationally quits Cabinet
Maria Miller finally resigns over expenses row
Skype pimps pro-level broadcast service
Playing Cat and Mouse with the media
Beat it, freetards! Dyn to shut down no-cost dynamic DNS next month
... but don't worry, charter members, you're still in 'for life'
EE dismisses DATA-BURNING glitch with Orange Mail app
Bug quietly slurps PAYG credit - yet EE denies it exists
Like Google, Comcast might roll its own mobile voice network
Says anything's possible if regulators approve merger with Time Warner
Turnbull leaves Australia's broadband blackspots in the dark
New Statement of Expectations to NBN Co offers get-out clauses for blackspot builds
Facebook claims 100 MEEELLION active users in India
Who needs China when you've got the next billion in your sights?
prev story

Whitepapers

Securing web applications made simple and scalable
In this whitepaper learn how automated security testing can provide a simple and scalable way to protect your web applications.
Five 3D headsets to be won!
We were so impressed by the Durovis Dive headset we’ve asked the company to give some away to Reg readers.
HP ArcSight ESM solution helps Finansbank
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Mobile application security study
Download this report to see the alarming realities regarding the sheer number of applications vulnerable to attack, as well as the most common and easily addressable vulnerability errors.