What is 5G and why does it matter?

Man using an old mobile phone © Alamy
Next-generation technologies can be cumbersome to start with

The next-generation system for delivering data to mobile phones promises to be better and faster in every way. But will it change how we do things?

What’s happened?

5G stands for “fifth generation”, meaning the latest, once-in-a-decade upgrade to the wireless systems that deliver data to mobile phones – an upgrade that will ultimately bring much faster connection speeds, better connections, and greater capacity. Strictly speaking, 5G means the updated set of international standards – ie, the technical ground rules – that govern how cellular networks operate, the details of which were hammered out last May. These standards cover all aspects of the working of a cellular network, including the radio wave frequencies used and how components such as computer chips and antennas handle radio signals and exchange data.

What were the previous “G”s?

1G refers to the first generation of wireless mobile-phone technology in the 1980s, introduced in 1979. 2G arrived in 1991, and the next decade saw mobile phones go mass-market, handsets get smaller, and text messaging take off. The first 3G networks were launched in 1998, but it was slow to catch on, and only really found its killer app with the advent of smartphones from 2007 onwards. Indeed, it was only with the advent of much-faster 4G, from 2008 on, that mobiles lived up the promise of 3G.

Why is 5G such a big deal?

Partly, it’s about speed. A typical decent download speed on 4G is about 20 Mbps (megabytes per second). EE reckons its 5G users will achieve ten times that, and as the technology matures it’s expected to get even faster. So an HD film that takes 30 minutes to download now will in future be done in under a minute. In practice, says Alex Hern in The Guardian, “almost everything you would do with a 5G connection would be instant, or limited by factors other than connection speed”. But while speed might be the way to get early adopters to shell out premium prices, the real advantages are less flashy, but arguably more important: capacity, coverage and latency.

Why more important?

Take capacity. A typical 5G tower will be able to handle 100 times more unique devices, according to Huawei’s Paul Scanlan, meaning that overloaded base stations become a thing of the past (and potentially make separate home broadband connections redundant). Moreover, 5G standards mean that those base stations can be far smaller than previously possible (about the size of a mini-fridge). That means that masts can be put up much more cheaply in far more locations than were previously possible – boosting coverage, and connecting at least one million devices per square kilometre. Together with latency of virtually zero, these factors promise a far more reliable network – and open up new (and as yet unimagined) uses for 5G, with the ability to expand beyond computers and phones to encompass the cloud and a whole new universe of “internet of things” devices.

What is latency?

Latency refers to the fraction-of-a-second time lag between issuing a command on a device and the device responding. In practice, it’s a measure of the speed at which a bit of data can do two legs of a journey. With 4G, a lag of between 50 and several hundred milliseconds is common, in part because signals must pass between different switching centres. 5G uses radically new networking technology that will cut latency to as little as a millisecond – a crucial factor in key 5G applications, which are expected to include virtual reality, augmented reality and mobile gaming, as well as fields such as remote surgery and driverless vehicles.

When will all this happen?

In the UK, EE (owned by BT) launched its first 5G service on 30 May, with its lowest price deal at £54 a month plus £170 for a compatible handset. But this only buys 10GB of data a month, and is only available in certain big cities. Vodafone starts a rival offer in early July, and other countries rolling out 5G this year include South Korea, the US, Germany, Switzerland, South Africa, Australia and China. The slightly mundane reality, though, is that 5G could be like 3G – and “fly low” for several years before it takes off. That’s partly because there are too many unknowns about how 5G will develop. And it’s also because the infrastructural investment required by operators is so massive (estimated at several hundreds of billions, at least). That invites some caution, given that telecoms companies – especially European ones – have generally underperformed in recent years and are wary of getting burnt.

Will China dominate 5G?

China began planning its upgrade to 5G in 2013, and some analysts believe it has taken an unassailable lead. It also has 800 million users of mobile internet, with three-quarters of them using mobile-payments technology. That will provide a ready-made market to target with high-tech services. Yet there is no reason why the US, or even Europe, could not catch up, says Rana Foroohar in the Financial Times. China’s market leader, Huawei, is bogged down in struggles with the US, and many other countries. By contrast, the US firm Qualcomm has settled its battle with Apple, and can build on its status as the first company to launch a 5G chip set.

But China is ahead?

It’s important which countries build their networks first, says Foroohar, but it’s not the only factor (and, in fact, South Korea will be the first country to have an operational 5G network). But the real commercial/strategic advantages of 5G are going to come from the ways in which individual enterprises and industries exploit the potential gains it will open up, not least when it comes to data-mining. “Just as no one predicted that one of the major uses of 4G would be a new way of calling taxis, the most important uses for 5G technology are also difficult to predict before they’re actually available,” noted analyst Dan Wang of Gavekal Dragonomics recently. “The battle for 5G isn’t set – and it doesn’t have to be a zero-sum game”.