4G is the latest set of standards for mobile phones, notable for being the fastest connections currently available for consumers.
Why "4G"?
4G means fourth generation, meaning the fourth major stage of changes to the standards used by mobile phone manufacturers and networks to ensure compatibility. The first generation was the original analogue mobile phones, 2G refers to the introduction of digital connections in 1991, and 3G refers to the introduction of mobile data services a year later.
None of these terms have any connection to Apple's iPhone range such as the 3GS or the 4S, which are purely Apple terms referring to the handset development.
What does 4G bring?
The 4G standards are primarily about speed: they require a minimum speed of 100 Mbit/s for people moving quickly such as on trains, and 1 GBit/s for people who are relatively static such as pedestrians or people sitting in one location. To put that into context, 1GBit/s would be considered a usable but mediocre speed for home broadband.
The main aim of 4G is to provide enough speed that users can treat it as a mobile broadband, carrying out the same type of activity such as streaming video that they can do on a fixed line connection. The biggest breakthrough is that 4G isn't just suitable for smartphones, but can also be used as the main form of internet connection even in areas without reliable broadband.
There is some controversy over the term as technically many newer mobile network systems don't meet all of the requirements, but the "4G" name has widely been adopted to cover all "higher speed" networks that are being developed.
How does 4G perform in practice?
In areas where the technology is available in the US, many users have found connections far slower than the advertised maximum speeds. However, there is still a significant improvement and generally users have found they get a connection around 10 times quicker than an equivalent 3G connection in the same area.
When are we getting 4G phones in the UK?
Although there are some tests of the technology, including in remote areas such as Cornwall, and although the major operators are already working on upgrading their networks to cope with the system, it appears it may be some time yet.
The rights to use the relevant frequencies will be auctioned off by the government, similar to a lucrative scheme used for 3G services a decade ago. This auction was originally scheduled for 2012 but has now been pushed back a year. That's raised questions about the reliability over the rest of the timetable produced by communications regulator Ofcom. It's current plan is for networks to begin offering services in some areas in late 2013 or 2014, with "widespread availability" in 2015.
