Mobile operators have been offering 3G services for nearly a decade and have continued to refine the technology, squeezing extra speed out of the existing infrastructure and standards.
Currently, 3G HSPA+ technology can deliver a theoretical download speeds of 42Mbps, but with demand for mobile data (and in particular video) constantly increasing, 3G is beginning to show its age.
That's why there is so much interest in the next wave of wireless — known collectively as 4G — which hold the promise of even faster downloads. But while other countries have raced ahead, in the UK adoption has been slower.
What is 4G?
4G is the next generation of mobile communication standards, picking up where 3G drops off and delivering higher download and upload speeds.
There are several technologies competing to become the de facto 4G standard. The term 4G doesn't actually refer to a particular technology — rather it's a catch-all term that in the UK is generally used to refer to Long Term Evolution (LTE).
In other countries, such as the US, different technologies — such as WiMax — have been deployed to provide higher-capacity data services. In the UK, WiMax is very rare, with just a few small operators serving specific towns or cities.
LTE versus WiMax
WiMax uses underlying technology based on Wi-Fi, whereas LTE is based on the same underlying technology that currently underpins every big UK mobile operator's 3G network. This is why we will have 4G LTE as the standard technology rather than WiMax (making the situation considerably more clear cut for end users in the UK than in the US, where both technologies have already been widely deployed).
So in the UK, at least, the future of 4G is LTE. And LTE, like every other data communication standard, operates in a specific frequency or set of frequencies.
But to add to the complexity, the UK's LTE services operate in a different band to those in the US, meaning that certain 4G-equipped devices won't work everywhere in the world.
You can think of the issue with different 4G bands in a similar way to how you used to have to check whether a phone was dual, tri or quad-band to see if it would work abroad.
In the UK, LTE services will use the 800MHz, 900MHz, 1800MHz and 2.6GHz bands whereas the new iPad, for example, will only work on 4G networks that use the 700MHz or 2.1GHz frequency bands.
So if you're on a trip to the US anytime soon and are considering snapping up a new 4G-equipped phone or tablet, be aware that it almost certainly won't be compatible with the UK's 4G networks.
Why should I care about 4G? Will it really be that fast?
Have you ever been out and about trying to watch a video on YouTube or stream some music and have it steadfastly refuse to playback without constant buffering? Yes? Well, that will be a thing of the past with 4G.
Of course, that was the promise of 3G but it never quite seemed to be the case.
Where 3G HSPA+ speeds are currently maxing out at around a theoretical 42Mbps downstream limit, 4G promises to deliver up to 100Mbps for users on the move.
But it's not just for urban hipsters — 4G could also play a role in bridging the rural broadband divide in the UK.
If it's used a replacement for fixed-line broadband, even higher speeds are possible, depending on reception and how many people are using the service. In fact, several of the test deployments of 4G services in the UK have taken place in rural locations such as Cornwall.
It's hard to say exactly how much faster the 4G services will be in the UK, as current trials are exactly that and are therefore not subject to true fully laden network conditions. As a rough guide, I've had a play with two different 4G services so far, and the download speeds ranged from just below 40Mbps in a moving car and up to 48Mbps when stationary.
When will 4G arrive in the UK?
There is still no definitive launch date from UK operators; but it's not (just) their fault.
The earliest likely date for widespread 4G availability in the UK, from a range of operators, is the autumn of 2013. The UK was one of the first countries to hold 3G spectrum auctions in Europe, but it will be one of the last to hold its 4G auctions.
The UK's telecoms regulator Ofcom has been mulling the idea of an auction of the spectrum needed to run 4G services in the country since 2008. However, due to a range of factors, such as the analogue television switch-off and the unequal allocation of spectrum currently used for 2G and 3G services, the process has hit a number of delays.
Considering what's at stake (their future business and current multi-billion pound investments) it's understandable (but not necessarily forgivable) that the operators have also been bickering about the fairest way to run the auction.
Operators cannot begin to offer their services before the spectrum auction takes place — and the process is not due to begin until the end of 2012. By the end of this year, Ofcom will have taken applications from prospective bidders with a view to start the bidding early in 2013.
As a result, big UK operators like O2 and Vodafone are unlikely to be able to use the spectrum for 4G before autumn 2013.
Everything Everywhere's 4G service
However, while the spectrum auction (800MHz and 2.6GHz) is still scheduled to take place before the end of 2012, Everything Everywhere has been given permission by Ofcom to re-use its 1800MHz spectrum currently used for 2G services for 4G services, effectively given the company a head-start on its rivals.
It also said it has begun trials of its 4G technology in London, Bristol, Cardiff and Birmingham. These cities will be the first places to offer the service. EE aims to extend the reach to a further 12 cities (Belfast, Derby, Edinburgh, Glasgow, Hull, Leeds, Liverpool, Manchester, Nottingham, Newcastle, Sheffield and Southampton) before Christmas 2012.
While it gave no solid date for the first introduction, chief executive Olaf Swantee said EE aims to provide 4G coverage for 20 million Britons before the end of 2012, rising to 70 percent of the country by the end of 2013, and 98 percent by the end of 2014.
Another LTE service
If, for some reason you absolutely have to use 4G sooner, you can — there is one very limited 4G service being offered already in Southwark, South London and also in Swindon.
However, the company behind the service — called UK Broadband — is a bit of an anomaly as it delivering the service using Time-Division Long-Term Evolution (TD-LTE) in the 3.5GHz frequency.
Unlike 'standard' LTE, Time-Division Long-Term Evolution was previously thought to be unsuitable for 4G due to the type of spectrum it operates in (lower-band spectrum tends to perform better at things like passing through the walls of buildings) but this has since been reconsidered.
"The UK was one of the first countries to hold 3G spectrum auctions in Europe, but it will be one of the last to hold its 4G auctions"
One stumbling block for TD-LTE is that there are at present very few phones in the UK that support it. There are some Mi-Fi devices that support it, which will let you connect to the hotspot by Wi-Fi like normal, but it's not a very elegant solution.
Everything Everywhere — or EE, as it is now called — has announced a handful of handsets that will work on its forthcoming 4G network, including the Nokia Lumia 920, the Samsung Galaxy S III LTE, and the Apple iPhone 5.
How much will 4G cost in the UK?
Understandably operators aren't keen to start talking pricing when the service is so far away from going live.
Mobile contracts are likely to include 4G data usage in the same way that 3G data is included today. Like any new technology, this will likely come at a premium initially, but I'd be surprised if it costs more than — say — £10 more than today's contract deals.
By the time the services are live the companies involved will have cumulatively spent billions of pounds deploying 4G in the UK. The last thing they would want is lacklustre uptake of the service and an even longer period before they can recoup their costs and start making money off the infrastructure upgrades. To promote widespread usage, dare I say ubiquity, of the service, they'll make them as cheap as they can to tempt customers in.
How much telcos could end up charging for 4G data services on the per-MB level is more difficult to predict, though it would presumably still have to fall within EU guidelines from the pricing of data at a wholesale level.