Mobile phones used to be just for calling your friends, but with a super-fast mobile network set to launch in the UK, opening web pages in a split second and watching TV in high definition will soon be a reality for smartphone-addicted Britons.
It has taken years of legal wrangling, lobbying, interventions from two secretaries of state and head-scratching by regulators but, by the end of this month, Britain will have a 4G network. The country's largest operator, EE, will launch the service in 10 British cities on 30 October in a bid to grab an even bigger slice of the market than the 34% it already controls through its Orange and T-Mobile brands.
Every decade or so brings a new generation of mobile phone technology: 1G brought us the brick-like analogue phones that so date films made in the 1980s; 2G saw digital phones shrink almost to the size of business cards; 3G made phones "smart" and able to use data. So what is the "fourth generation" technology, and will EE's head start give it an unassailable advantage over competitors, who will have to wait until after this year's spectrum auction?
In essence, 4G is a way of squeezing larger amounts of data over radio waves. Essentially it turns your phone into a device with links to the internet as good as a desktop computer's – in theory making watching BBC iPlayer, video calling or multi-player gaming just as seamless on the move as it is at home.
Standards body the International Telecommunications Union (ITU) originally defined 4G as technologies that deliver speeds of one gigabit per second to stationary users, but today's version falls well short of that.
The top laboratory-tested speed on EE's 4G network is around 50 megabits per second (Mbps) – equal to superfast home broadband. In practice, the company is promising speeds of up to 12Mbps, which is not that different from the latest version of 3G.
"Technology-wise, 4G is an evolution," says James Barford, telecoms expert at Enders Analysis. "The latest version of 3G is quite close in performance to the current 4G. That said, EE's network will be virtually empty for at least six months, so the speeds experienced are likely to be impressive."
Actual speeds depend on many factors. Data moves more slowly in the wild than in a lab because information is carried in such large packages, that if there is any interference, the signal degrades fast. Other factors include the proximity of a mast, the speed of the phone's processor (the state-of-the-art chip inside Apple's new iPhone 5 makes a big difference), and the amount of other users drawing down information from the same cell on the network.
Networks vary in quality according to how many masts they have in a particular area. Owning lots of spectrum helps, too: spectrum is divided into bands, some of which are reserved for the military, or commercial broadcasters, but a growing number are reserved for mobile telecoms. The more bands of spectrum a network owns, the more room it has to carry data.
Cabling is also important. Mobile web traffic is typically carried over the air only as far as the mast. After that it travels through wires, which ultimately connect to the internet: some networks rely on cables that carry only a handful of megabits per second. Three and EE have installed higher-capacity cabling, and Vodafone's recent purchase of Cable & Wireless Worldwide will allow its masts to plug into one of the UK's largest fibre-optic networks.
Many consumers will wait until 4G is available on multiple networks and over a wide area before taking the plunge, says Ernest Doku at price comparison site uSwitch. "The early adopters, who have to have the latest and greatest technology, will switch to EE because it has the service first, but a lot of consumers could be prepared to sit on their hands."
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