The final whistle blows and the roar of the crowd fades. Around the stadium people are shifting in their seats, collecting bags and jackets. Some are already heading for the exits. You pull out your phone to check train times, or to fire up a ride-hail app.
Thousands of people around you are doing the same thing, and thousands more in the office buildings across the road, and in the train station around the corner, and the local 4G network simply can’t cope with that many concurrent connections.
4G can handle 4,000 individual connected devices per square kilometer, which sounds like a lot but quickly gets stretched to the limit when that square kilometer is an urban area with hundreds of households or offices, each with multiple connected devices, plus thousand more people passing through.
Two’s company, 28.5 billion is a crowd
5G will be able to handle a million concurrent connections per square kilometer. Not many events bring that many people together in one place, and even the world’s most densely populated cities (Manila is the current record holder at 41,515 people per square kilometer) don’t come close.
Of course, the real problem is that one person doesn’t equal one device. Today, a third of households in the US have 10 or more connected devices. And the IoT revolution has barely begun. Cisco expects there to be 28.5 billion networked devices by 2022. That’s three-and-a-half devices per person on Earth. It’s also a staggering increase of around nine million devices per day, every day, between now and 2022.
Without the dramatic improvements in concurrency and bandwidth that 5G promises, that explosion of IoT devices simply won’t be possible. But one of the technical features of 5G that will allow these improvements will have another impact that is often overlooked.
Location, location, location
Almost nobody talks about 5G’s potential to revolutionize location sensing, which is surprising given how many online services are location sensitive. Ride-hailing, navigation, local search, delivery services – many apps we use day-to-day rely on knowing where your device is on the surface of the Earth. Most of these use Global Navigation Satellite Systems (GNSS), such as GPS – a technology that hasn’t fundamentally changed in 40 years.
5G’s pumped-up speed and bandwidth are partly due to the use of much higher radio frequencies. The downside is that 5G signals will have a much shorter range than lower-frequency 4G signals, which will mean many more cellular towers will be needed for the same coverage.
These will be much smaller than the cell towers we are used to – more like small pizza boxes – but there is no escaping the need for many more of them, dotted on the sides of buildings, telegraph poles, roofs, etc. These towers will also be more sophisticated, able to detect the direction of incoming signals and to directionally “beam” outgoing signals.
More cell towers mean your device will be much closer to the nearest one and often in line of sight of several. Measuring the direction and time taken for signals to travel between devices and cell towers will enable very accurate geo-spatial positioning. And none of this will involve consulting venerable satellites in high Earth orbit, or the latency of a 20,000+ km signal travel the distance that involves.
The 5G standards group, 3GPP, has agreed on a large number of location and context-awareness KPIs, including target accuracies, for use cases ranging from emergency response to push advertising.
Know your place
Location sensing was always possible with 4G, but not very accurate. A 4G network knows where your device is to within about a mile. Because this was useful for emergency services, additional technologies have evolved to tighten this radius, but GNSS remain the only really accurate geo-spatial location option.
GNSS has some major limitations though, the most notorious being that it doesn’t work well, or sometimes at all, if you can’t see the sky. That’s a bit like a messaging app that only works if you can see the person you’re messaging. GNSS apps are also very power hungry. 5G promises to overcome these weaknesses, delivering always-on, extremely accurate location sensing with trivial latency.
Back in your seat at the stadium, not only will you get a superfast connection at the same time as thousands of other people, your ride-hailing service will be able to tell where in the stadium you are, how long it will take you to get to the nearest exit, and maybe even suggest a ride share with the guy two rows back who’s going in the same direction.
Read more about the value 5G can bring to industry.
This blog is part 4 of a series of five written by Capgemini Europe Chief Technology and Innovation Officer, Gunnar Menzel.
Read part 5 of this series – Five new ways to think about 5G: A sea change.
Missed the previous blogs? Read them here:
Part 1: Five new ways to think about 5G: The element of surprise
Part 2: Five new ways to think about 5G: In space, no one can hear your latency
Part 3: Five new ways to think about 5G: The speed trap