If you’ve had a phone contract with mobile data for a long while, you’ll know exactly how much things have improved over the last few years.

The introduction of 4G saw speeds increase significantly, but only where you can get coverage. And even in cities with supposedly good 4G, you can still end up with a poor signal or poor speeds.

5G aims to fix all of this, as well as vastly expanding the mobile network’s ability to handle the millions of new devices that will be connecting over the next few years.

So what is 5G?

As with 1G, 2G, 3G and 4G before it, it’s an umbrella term for the fifth-generation of mobile networks. Within 5G there’s lots of jargon, most of which you really don’t need to know about or worry about – at least not until there are competing standards or you need to make sure you buy a 5G phone with the right specs to work with your mobile operator. Hopefully, though, that won't happen, and you'll be able to buy a 5G phone in any country and use it around the world.

5G will be much faster than 4G. In technical lab tests, 4.5Gb/s (4500 megabits per second) and more has been achieved, but in the real world you can expect between 10 and 20 times better speed than 4G. That’s according to companies including Qualcomm, Huawei and Samsung.

If that’s true, the broadband connection on your phone is likely to overtake your home broadband speed by quite a margin. And that applies to upload speeds as well as downloads, so posting a 4K video you’ve just shot on your iPhone 13 to YouTube as you walk along the high street in 2020 should become a reality.

Currently, 4G speeds are around 10Mb/s  for downloads, which means actual 5G speeds between 100 and 200Mb/s from 5G.

Between 2014 and 2020 it’s estimated that mobile traffic will have increased more than 30 fold. That’s partly because people want to stream video when they’re out and about, but also because of the number smartphones has increased considerably.

And it’s about to get a whole lot more crowded. We’re already seeing car manufacturers put 4G SIMs in their vehicles, but when self-driving cars hit the roads they’ll all have a 5G connection.

Infrastructure such as traffic lights could communicate via 5G to work with cars to ensure the speediest flow of traffic.

5G is 10x more responsive

As well as being faster than 4G, 5G will be a whole lot more responsive, so you won’t have to wait those few seconds before your YouTube video starts playing. The lower latency and faster speeds should also mean you’ll be able to have much higher quality video calls, which are currently poor quality and often laggy when using 4G.

Do I need a new phone for 5G?

Yes, but don’t rush to buy one. Current phones have 4G LTE modems, which are incompatible with the new technology used in 5G. The only phone right now which will be upgradeable to 5G is Motorola’s Moto Z3. But you’ll have to snap on a 5G Moto Mod to get it to work then 5G arrives, and even then it’ll only be on Verizon in 4 US cities. Hardly a fantastic solution.

Motorola Moto Z3 will support 5G with a Moto Mod

However, as with 4G, you’re unlikely to have any 5G coverage for a while as it will be rolled out gradually starting with major cities. It probably isn’t going to be worth paying more for a 5G contract in the early days unless you happen to live and work in a town or city with excellent 5G coverage.

By the time 5G coverage approaches the level 4G is at now, almost everyone will have a 5G compatible phone. And that’ll probably be around 2025.

When will 5G be turned on?

Trials are already happening, such as EE’s test in East London. It’s likely the UK will get the first public 5G coverage in 2019 or 2020.

In the photo you can see the new 5G antennae on Cheapside House:

EE 5G trial in East London

South Korea is typically ahead of others, and is set to get 5G switched on in 2019. China is also attempting to roll out 5G by next year.

How does 5G work?

That’s a tricky question to answer, as it’s a complex technology.

In essence, it mainly uses much higher frequencies than 4G where there is plenty of ‘spectrum’ available. 4G works on frequencies between 2 and 8GHz. 5G will use these frequencies as well as the higher band between 24 and 100GHz.

5G frequencies - mmWave

This is what’s being called ‘millimetre wave’. It refers to the fact that, as frequency increases, wavelength decreases. These shorter waves – just as with 802.11ac Wi-Fi compared with 802.11n – mean much faster internet speeds, but at the cost of shorter working distances.

The problem is that 5G ‘mmWave’ signals can’t pass through walls and will be affected by obstacles such as tree branches and even rain. What it means in practice is that there will need to be a lot more mobile transmitters located much closer to the ground to create the necessary coverage.

The principle of more, smaller transmitters also means there should be excellent indoor 5G coverage as well as outdoor.

Will 5G be in rural areas too?

Millimetre wave is currently a good solution for densely populated areas – i.e. cities – but this kind of technology is too expensive to cover rural areas, so it unfortunately your 5G phone will simply use existing 4G signals if you go out of mmWave coverage.

Some experts say that 5G will fix the currently awful mobile signal on railway lines, offering ‘seamless’ connectivity so you should be able to binge watch Orange is the New Black on your commute to and from work.

However, that will depend upon how much rail operators – that’s Network Rail in the UK – are willing to invest as upgrading to 5G isn’t cheap. So don’t expect to see much improvement for several years after 5G is first introduced.