Feeds

WTF is... White Space radio networking?

Channel surfing

The essential guide to IT transformation

Is it safe to play here?

The problem is that the device running at point X has to know the frequencies that transmitter A is using, and while various detect-and-avoid technologies have been tried only an online look-up table of locations listed against available frequencies has been shown to actually work.

So a White Space device, regardless of the protocol it will eventually use, has to first query a database to establish which frequencies are available at its current location. If a star topology is being used - such as a single Access Point providing internet connectivity to nearby clients - then only the centre of the star needs to check with the database, the clients can take guidance from the hub.

White Space geo-database model

To use White Space frequencies, you router and devices may have to check there's available capacity from multiple databases
Source: Ofcom

Until the first of these databases was established, in December 2011, broadcast TV had exclusive usage of every White Space frequency. The US broadcast trade body, the NAB, recruited the pneumatic Dolly Parton and an evil, animated telephone to its campaign against the exploitation of White Space, claiming that White Space usage would inevitably interfere with broadcast pictures, despite the US Federal Communications Commission's insistence that there was room for everyone to play.

The angry phone

An angry, White Space-phobic phone, yesterday

In the UK, the Church of England and Andrew Lloyd Webber were roped in to support a similar campaign, centred not on the claim that White Space would knock out broadcast TV but that the White Spaces had hitherto been the exclusive preserve of wireless microphone users.

Professional wireless mics, used in everything from West End shows to Celebrity Big Brother, already use a similar database system to allocate frequencies by region, but the limited quantity of microphones in use has never required real-time dynamic allocations. Touring shows generally know were they're going to be well ahead of time.

Lily Allen and Sennheiser radio mic

A popular radio mic user is undaunted by White Space networking
Source: Sennheiser/John Marshall

The Joint Frequency Managers Group (JFMG), an organisation set up specifically to manage those bands for wireless microphone users, has run the monopoly database for years but has done so with the willing co-operation of the whole entertainment industry.

In the US, the White Space rules conceded a couple of channels for exclusive use by wireless microphones. Something similar will probably happen over here. The entertainment business may feel a bit squeezed, but the rest of us get masses more bandwidth to play with.

Next gen security for virtualised datacentres

Next page: Radio Waives

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
5 things you didn’t know about cloud backup
IT departments are embracing cloud backup, but there’s a lot you need to know before choosing a service provider. Learn all the critical things you need to know.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?