Feeds

Faster mobile data: the road to 4G

Better LTE than never

  • alert
  • submit to reddit

Build a business case: developing custom apps

Feature

The great thing about standards, as some wit once said, is that there are so many to choose from. Mobile phones are afflicted worse than most technology – a multiplicity of standards, nested within one another like a messy set of Russian dolls filled with alphabet soup.

The 'generations' of mobile networks are fairly loose, but appear roughly once a decade: the first, analogue, 1G cellular networks around 1981, then digital 2G in about 1992. The latest is 4G, but its not as clear cut a step ahead of its predecessors as they were to theirs.

Generic mast

Source: Karl Baron

At the turn of the century, 3G was formally defined to mean data speeds of at least 200Kb/s by the International Telecommunication Union's IMT (International Mobile Telecommunications) 2000 specification. However, IMT -2000 didn't specify the "air interface" – the radio link from phone, tablet or modem to mast – so two competing standards developed out of the two prevailing 2G systems.

GSM, as used by about 85 per cent of the world, yielded UMTS (Universal Mobile Telecommunications System). UMTS uses the W-CDMA (Wideband Code Division Multiple Access) air interface. It's the form of 3G we in the UK are used to.

The battle for the air interface

In America, Qualcomm upgraded its CMDMA technology to create CDMA 2000. It's used in the US and parts of Asia, predominantly South Korea. CDMA 2000 devices don't work on UMTS networks and vice versa, although both are 3G because that moniker dictates how fast they can move data, not the technology they use to do it.

Likewise, 4G is primarily a speed requirement. The successor to the ITU's IMT 2000 specification is IMT Advanced and was defined in 2008. It stipulates that 4G should deliver data speeds to users of around 100Mb/s if they are moving, rising to 1Gb/s if they're standing still.

LTE FDD and TDD

LTE now comes in two flavours: FDD (Frequency Division Duplex) and TDD (Time Division Duplex)
Source: Qualcomm

Existing mobile networks have two, parallel infrastructures: one, circuit-switched, for voice calls, and a separate, packet-switched layer for data traffic. 4G is a pure packet-switched TCP/IP network, running everything over IPv6. Voice becomes just another data type.

By the time the ITU defined IMT Advanced, two competing systems were already under development, each formed from the two 3G systems. A group called 3GPP (3G Partnership Project) developed LTE (Long Term Evolution), a successor to UMTS. Meanwhile, the totally separate 3GPP2 was working on UMB (Ultra Mobile Broadband), an upgrade to Qualcomm's CDMA2000.

The essential guide to IT transformation

More from The Register

next story
Reg man looks through a Glass, darkly: Google's toy ploy or killer tech specs?
Tip: Put the shades on and you'll look less of a spanner
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
One step closer to ROBOT BUTLERS: Dyson flashes vid of VACUUM SUCKER bot
Latest cleaner available for world+dog in September
Samsung Gear S: Quick, LAUNCH IT – before Apple straps on iWatch
Full specs for wrist-mounted device here ... but who'll buy it?
Apple promises to lift Curse of the Drained iPhone 5 Battery
Have you tried turning it off and...? Never mind, here's a replacement
Now that's FIRE WIRE: HP recalls 6 MILLION burn-risk laptop cables
Right in the middle of Burning Mains Man week
Apple's iWatch? They cannae do it ... they don't have the POWER
Analyst predicts fanbois will have to wait until next year
Tim Cook in Applerexia fears: New MacBook THINNER THAN EVER
'Supply chain sources' give up the goss on new iLappy
HUGE iPAD? Maybe. HUGE ADVERTS? That's for SURE
Noo! Hand not big enough! Don't look at meee!
prev story

Whitepapers

Top 10 endpoint backup mistakes
Avoid the ten endpoint backup mistakes to ensure that your critical corporate data is protected and end user productivity is improved.
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 distributed data
Eliminating the redundant use of bandwidth and storage capacity and application consolidation in the modern data center.
The essential guide to IT transformation
ServiceNow discusses three IT transformations that can help CIOs automate IT services to transform IT and the enterprise
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.