Feeds

Rural white space wireless standard signed off

After seven years, 802.22 is official

5 things you didn’t know about cloud backup

Nearly seven years after the IEEE’s 802.22 working group was first formed, the 802.22 standard has been published.

The standard is designed to take advantage of television “white space” frequencies between channels. As countries roll out digital television and reallocate the spectrum previously occupied by broadcasters, vacant channels become more common. In America, carriers are fighting a rearguard action against the FCC’s white space spectrum rules; trials are underway in the UK; while the use of old analogue TV spectrum is the matter of intense lobbying by carriers, broadcasters and emergency services in Australia.

The 802.22 standard – already being wrongly-identified as a Wi-Fi standard by world+dog – has to support a huge range of carrier frequencies to live in the television spectrum: from 54 MHz up to 862 MHz.

It has to cope with other challenges as well: the physical and MAC layers have to be able to cope with long round trips between towers and end users, and to support propagation at up to 33 Km from the base station, the standard also needs to cope with channel fading.

The other big challenge is deciding which channels to use, since the frequency that happens to be lying fallow in any given location will depend on which TV channels are in use. The “cognitive radio” systems defined under 802.22 have a range of protections designed to prevent interference with local TV broadcasts: base stations can sense the presence of broadcasts, and also combine GPS geolocation with a spectrum database lookup to identify channels that should be vacant in a given location.

An addendum to the standard to protect wireless microphone users, 802.22.1, is nearly complete and should follow shortly.

The standard is designed to deliver “up to 22 Mbps” in an 8 MHz TV channel (its best-case spectral efficiency when all is well is 3.12 bits/Hz), but that capacity is designed to be shared between as many as a dozen users per tower.

A presentation by the 802.22 working group can be downloaded here. ®

5 things you didn’t know about cloud backup

More from The Register

next story
6 Obvious Reasons Why Facebook Will Ban This Article (Thank God)
Clampdown on clickbait ... and El Reg is OK with this
So, Apple won't sell cheap kit? Prepare the iOS garden wall WRECKING BALL
It can throw the low cost race if it looks to the cloud
EE fails to apologise for HUGE T-Mobile outage that hit Brits on Friday
Customer: 'Please change your name to occasionally somewhere'
Time Warner Cable customers SQUEAL as US network goes offline
A rude awakening: North Americans greeted with outage drama
Shoot-em-up: Sony Online Entertainment hit by 'large scale DDoS attack'
Games disrupted as firm struggles to control network
We need less U.S. in our WWW – Euro digital chief Steelie Neelie
EC moves to shift status quo at Internet Governance Forum
BT customers face broadband and landline price hikes
Poor punters won't be affected, telecoms giant claims
prev story

Whitepapers

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.
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.
Backing up Big Data
Solving backup challenges and “protect everything from everywhere,” as we move into the era of big data management and the adoption of BYOD.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
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?