5G - what is it, and do we need it?

Here's the reality behind the 5G hype

Every year, just before Mobile World Congress in February, Computing is deluged with news about 5G technology (this year, just before the tech was trialled at the Winter Olympics in Pyeongchang, was even worse). It's 'coming soon', they promise. It's 'double the speed' of 4G. It's got support from 'major vendors'.

But what actually is it, and when will it really be here?

What is 5G?

5G is a new mobile wireless technology - not a standard - that is set to be established in the UK by 2020. Just like every other generation of cellular technology, It won't be compatible with existing standards today - although all first devices will need to support 4G, both due to the expected slow spread of 5G and the need to use the 4G platform to make an initial connection.

The tech promises much more bandwidth, more speed, more devices per base station - 5G is trotted out as a panacea every time someone mentions clogged spectrum - and lower latency than 4G. The National Infrastructure Commission called it 'ultra-fast, ultra-reliable, ultra-high capacity transmitting at super low latency'.

However, much of the specifics are still up in the air.

How does it work?

The key point about 5G is its use of higher frequencies than previous generations: as high as 50GHz.

On the plus side, those high-frequency (HF) signals mean more speed, bandwidth, and all of the other features that vendors like to parade in front of end-users. On the downside - and this is a big one - the so-called millimetre-wave HF bands are much weaker than the low-frequency (LF) spectrum.

HF waves have a shorter range than those in the LF spectrum, and can't travel through objects as easily; at very high frequencies, they can even be blocked by foliage. That means that cities, where 5G is going to be most useful, present a real challenge.

The solution is to pack an area with a high number of small cells, rather than using a single massive mast. The International Telecommunications Union (ITU) has stipulated that 5G base stations will need to support as many as one million devices over a square mile.

Rolling out a new country-wide infrastructure like this - with up to 20 times the number of existing base stations - is a massive and expensive undertaking.

At least some of last year's widespread confusion has been cleared up in 2018, though: the 3GPP organisation, which oversees cellular standards, agreed on a 5G specification in December.

Who's working on it?

Every major mobile maker has been investigating 5G for a long time, but it wasn't until Qualcomm showed off its X50 modem last year that devices actually looked like they might appear this decade.

Samsung has been experimenting with 5G since the early 2010s, and Apple entered the arena last year. With Qualcomm's new modem, though, the usual suspects have signed on, including Sony, LG, Nokia and HTC.

Together with the Global Certification Forum's moves towards a 5G phone certification, that could mean the first 5G smartphones being launched in 2019, or even late 2018 - although without the actual 5G networks, yet.

Network equipment vendors like Ericsson and chip makers like Qualcomm want to push 5G as fast as possible; demand in their products has fallen markedly since 4G investment tailed off.

Telecom operators, though, lack a clear business case and are less keen to get started. Building 5G networks - with their massive requirements for antenna, base stations and fibre optic cabling - will not be cheap. On top of that, operators' revenue-per-gigabyte has fallen dramatically over the last decade, while cost-per-gigabyte hasn't decreased nearly as much. That hasn't stopped Vodafone and EE from talking about 5G, but any sort of ETA has been oddly hard to pin down.

When is it going to get here?

Despite the expense, the complexity and the uncertainty, the Government remains committed, announcing 5G funding in Budgets from George Osborne and Philip Hammond (twice). Still no mention of a launch date, though…

As it stands now, the UK's 4G rollout has been only a partial success, with networks still mostly centered on cities. We're a long way from achieving nationwide coverage - which doesn't bode well for 5G.

Outside the lab, there have been some trials in real-world locations; Samsung and Arqiva tested a 'fixed wireless access' network last year, for example. Despite that, a widespread rollout is likely to be at least two years away.

Why should CIOs care?

5G could make browsing Facebook and downloading films on the move much faster, and possibly provide an alternative to fixed-broadband in homes and offices - but that's not its main draw for the enterprise.

Ericsson has been demonstrating a 5G technology it calls 'network slicing' (a variant of software-defined networking), which is already being used by NTT Docomo in Japan and SK Telecom in South Korea. This technique can be used to create bespoke networks for very different applications on the same physical infrastructure: from smartphones to autonomous cars.

"Since the slices are isolated from each other in the control and user planes as well supported use case, the user experience of the network slice will be the same as if it was a physically separate network," Ericsson says.

5G will already be capable of supporting "millions" of devices - at least, according to the ITU - making it perfectly suited for the IoT. Network slicing builds on that by enabling a single network to connect many different IoT products: from medical devices and wireless sensors to industrial equipment and agricultural machinery.

In addition, the low latency and (claimed) high reliability mean that applications like unified communications, medicine and self-driving cars (again - it really is the go-to 5G app) will be easier and safer to use.

It's a rosy vision of the future, but when and how will it come to pass?