What is 5G?

You might have heard that the UK’s first ever 5G network has just been launched. With growing coverage across major UK cities, it promises faster speeds than ever. But what actually makes it different from previous networks? Izzie Clarke and Katie Haylor were joined in the studio by Paul Beastall, member of the UK5G Advisory Board, but what is 5G?

Paul - 5G simply is the fifth generation of mobile phone technology.

Izzie - Oh, and that's what the G stands for. I've actually never really thought about it. What is it and how is it different from 4G?

Paul - It's the latest evolution. It brings a number of technologies together so it uses higher radio frequencies that allow us to get more information through a given radio channel. It brings computing further out towards the edge of the network which means we can reduce latency so we can do services with far less delay. And it's also designed to cope with very, very high densities of simple terminals to allow us to connect everything in the long-term.

Izzie - We're seeing it rolled out in UK cities, is it anywhere else?

Paul - The UK's one of the leading countries, but it's certainly not the first. There's some deployments in the US, there's quite a lot of activity in Asia. From a technology perspective, most of the radio innovation is coming out of China, Japan, and Korea, but some of the applications are being developed in the UK, so we are still innovating.

Izzie - What's it capable of?

Paul - If we want to think about numbers, so we’re thinking about bit rates, targets of up to 10 gigabits per second which means you can download a DVD in 10/15 seconds, something like that in the best conditions possible, so not everywhere. For me, more interestingly, it means the latency, the delay across a network can drop down to only a millisecond, so a thousandth of a second, which means that when humans are interacting with networks we can have information overlaid on the top of what we’re doing. So you could do things like remotely control robots in real time doing very delicate and challenging tasks or use augmented reality to give our eyes more information than we can see ourselves.

Izzie - How is 5G able to hold so much more information than 4G?

Paul - There's two reasons. The first one is by going up in radiofrequency to higher parts of the radio spectrum there's more bandwidth available, so we can use more bandwidth for each radio channel which means we can just put more data through that. The other thing is it includes a technology called massive MIMO which allows us to actually send beams targeted at individuals users. At the moment, if you're on a radio base station on 4G, normally what you find is that capacity is shared among everybody else who's in the same street as you, with 5G we can literally point beams of radio energy at individual users.

Izzie - Paul, how is this all connected?

Paul - Effectively what we have, we have a radio in a handset or a terminal that’s in an embedded device - something like a car, and that makes a radio link to what we call a base station and all versions of mobile technology use this same architecture with base stations. And then from there it actually goes over optical fibre or fixed network connections back to what we call the core network which manages security and billing, and just make sure that everything works. Things like international roaming gets managed that way as well. So unlike Wi-Fi, which is just a short connection and then straight out to the internet, there's a whole network behind cellular technologies as well.

Izzie - Oh, wow. Are there any disadvantages to 5G compared to 4G?

Paul - Yes. At the moment it's expensive, it's new technology, it will take time to evolve. We see that with all new technologies so it's not going to be that we get all the benefit immediately. The millimetre wave frequency, these very high frequencies we're using have some challenges that they don't go through human bodies, they don't go through walls so actually, you need to be quite close to the base stations to get the service that you need. So we’re talking about smaller coverage areas, much greater performance.

Izzie - Do you think you could see those base stations incorporated into everyday life? Like could we have one, say, on a traffic light because we know that they're so useful when we have them everywhere?

Paul - Yeah, absolutely. And I think that's the change, so we’re going to go from network where we have 20,000 base stations per operator in the UK to potentially a million. 5G will enable some of the autonomous driving communication so I think street furniture, traffic lights, street lights are going to be really really important.

Izzie - Do you think this will ever take over 4G? Is this the end of 4G, essentially?

Paul - Not for a very long time. My iPhone does 2G, 3G, 4G. 2G's still not turned off here, it is in the US. So 4G will end eventually, probably, but not before 2030 at the earliest.