Whether intelligent parking systems or global logistics networks; without cellular networks, smart apps would not work.

The networks of tomorrow.

Professor Christian Wietfeld, Chair for Communications Networks at the Technical University of Dortmund, and Professor Michael ten Hompel, Managing Director of the Fraunhofer Institute for Material Flow and Logistics (IML), about the business impact of next-generation cellular technologies and a worldwide standard for narrowband data communications and why the future would come to a halt without them.
Copy: Roger Homrich
Photos: Oliver Krato

Digital transformation is driving the wholesale integration of economic and societal processes, largely based on cellular technology. Are our cellular networks ready for digitization?

Professor Wietfeld: It’s important to realize that cellular networks have undergone an amazing evolution in recent years. Who would have thought that today’s smartphones would transfer five to six gigabytes of data per month? And that’s modest by private user standards. Problems still remain, however. Coverage is good, but doesn’t reach everywhere. And data is still transferred with a certain delay. Clearly, the infrastructure has to continue evolving in order to make digitization possible.
Prof. Dr. Dr. h. c. Michael ten Hompel
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is the Chair of Materials Handling and Warehousing at the Technical University of Dortmund, the Managing Director of the Fraunhofer Institute for Material Flow and Logistics (IML) and a Director of the Fraunhofer Institute for Software and Systems Engineering (ISST). The electrical engineer is also a member of the National Academy of Science and Engineering (acatech) and the Logistics Hall of Fame.

By that, you’re referring to 5G, the super cellular standard known as LTE’s successor. Why do we need data rates that are faster than 1 gigabit per second, like with LTE Advanced?

Professor Wietfeld: Unlike its predecessors, 5G doesn’t focus exclusively on data rates. It’s more about enabling new classes of applications with demanding requirements, with latency first and foremost among them. Under 5G, latency – i.e. the delay between requesting data and actually receiving it – is only one millisecond. By comparison, latencies in today’s best networks range from ten to 20 milliseconds. Scalability is another key factor. The advent of the Internet of Things will introduce many more devices into our networks. And the networks need to be prepared.

And that’s where another cellular standard enters the picture: NarrowBand IoT, or NB-IoT for short. Why do we need NB-IoT if 5G is coming soon?

Professor ten Hompel: We need both standards: 5G and NB-IoT. Why? Well, 5G is a broadband technology that can transfer large volumes of data with low latencies. NarrowBand IoT, by contrast, uses very little power to transfer small amounts of information. Both technologies offer specific advantages for industry and end user applications. For example, NBIoT is powerful enough for text messaging or simple phone calls. But if you want to watch a movie, you’ll need 5G. Also, 5G supports the kind of realtime data communications needed to control industrial equipment.

Which NB-IoT obviously can’t do?

Professor ten Hompel: Correct. NB-IoT isn’t a realtime technology. It’s only suitable for applications that can tolerate latencies of up to ten seconds. That’s sufficient for most applications that we can currently envision in logistics, for instance. In logistics, you really don’t care if the location tracking information is several seconds old. You just want to know where a particular product or shipment is right about now. NB-IoT offers another advantage: ultralow power consumption. Many applications require low power consumption and long battery lives. With NB-IoT, simple devices can run for five to ten years without ever needing a new battery.
Prof. Dr.-Ing. Christian Wietfeld
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is the Chair for Communications Networks at the Technical University of Dortmund. The electrical engineer is a cellular network expert whose research interests include highly reliable communications for smart grids, e-mobility, autonomous vehicles and robotics.

Often, data rates are considered yardsticks of network quality. By that light, 5G isn’t an obvious choice. Does it have another important feature other than low latency?

Professor Wietfeld: I wouldn’t completely ignore data rates. The future will bring more and more applications that need higher data rates. Under 5G, data rates will increase to as much as one gigabit per second. Scalability matters a lot, too. LTE just can’t keep up when there are 250,000 devices sending and receiving data within a single square kilometer. That’s a multiple of the number of devices we currently have connected to the network.
Professor ten Hompel: Scalability is one of NB-IoT’s clear strengths. We’re talking about a 100-fold increase over conventional GSM cellular applications. That means we can attach 100 times as many devices to a single router. It’s an ideal feature for logistics because NB-IoT can be used to connect a large number of containers. Take a highbay warehouse, for example, that contains thousands of connected items, all sending data. That won’t work without NB-IoT.

Does NB-IoT have other advantages that distinguish it from 5G and favor the adoption of both wireless technologies?

Professor ten Hompel: NB-IoT is roughly 100 times more efficient at utilizing high frequencies. That allows us – in contrast to previous cellular standards – to send data from every building. Here’s a really down-to-earth example: whenever you step into an elevator or drive into an underground garage, you probably lose reception. Not so with NB-IoT. In my eyes, it’s not about whether we need one technology or the other. We need both.

But the low latencies offered by 5G surely depend on other factors, too. Didn’t providers have to build a denser antenna network for LTE?

Professor Wietfeld: Latency is about more than the lag between the device and the base station. What really matters is end-to-end latency, that is, the latency all the way to the server running the application. That’s why it’s so important to move the servers into the base stations, creating what we call an “edge cloud”. Essentially, application functionality is brought out to the edge of the cloud, which makes it possible to satisfy demanding latency requirements. Data also has to be brought into the landline network, and so the base stations need to be connected to a fiber optic infrastructure.

Does that mean we’ll be stuck with even more ugly antennas in the future?

Professor Wietfeld: Antennas are already nestled fairly close together in urban areas. Since 5G antennas – also known as Massive MIMO (Multiple Input, Multiple Output) antennas – are more powerful, the initial phase of the 5G buildout can get by with our current base stations. In areas with ultra-high demand, though, new base stations will be needed. In these cases, innovative, highly flat geometries will make it possible to integrate antennas into buildings elegantly. So there may be more antennas, but they won’t be an eyesore.

There are still no mass-market products based on NB-IoT. And we won’t have stable nationwide networks before the end of 2018. How long will it take for NB-IoT to reach the mainstream?

Professor ten Hompel: NB-IoT has a lot of mainstream appeal. These are lowcost applications with immediate and concrete paybacks. In the next five to seven years, we expect to have around 20 billion devices, many of which will be connected over NB-IoT. Just think: that’s double the number of devices in our current Internet. We will be tripling the size of today’s Internet within just a few years. It’s a tremendous challenge and a gigantic market.

What industries will benefit the most from NB-IoT?

Professor ten Hompel: All the industries that transfer and need relatively small amounts of information will benefit from NB-IoT. It will enable a host of end user applications such as utility metering. Or take something as simple as a doorbell. One day, it, too, might offer NB-IoT functionality so that you can send doorbell signals to your cell phone, potentially augmented by a small camera. But the main focus is on industrial applications. The ability to extend processes beyond and across organizational boundaries will play a big role in integrating production, retail and logistics networks in the future.
“In my eyes, it’s not about whether we need 5G or NarrowBand IoT. We need both.”
Chair of Materials Handling and Warehousing TU Dortmund

What applications will use 5G?

Professor Wietfeld: The prototypical 5G application is automated, connected driving on public roads. Being a safety-critical application, it requires realtime communications and guaranteed reliability.

Germany isn’t exactly a pioneer in autonomous driving. Can we even expect Germany to play a leading role in the introduction of 5G?

Professor Wietfeld: Don’t underestimate Germany’s capabilities in autonomous driving. We’re definitely in the 5G vanguard since 5G’s killer apps target our core industries: automotive, energy and logistics. That opens up big opportunities for us. But the competition isn’t resting on its laurels. Asia and the US are pressing ahead with 5G at a rapid pace. We’ll have to push ourselves if we want to keep up. Luckily, Germany is in a very good position for the future.

When will we have a full-coverage 5G network throughout Germany?

Professor Wietfeld: The 5G rollout will probably take several more years. Pilot applications are expected to start coming out in 2018. But they will be highly localized. For that reason, I don’t expect to see full 5G coverage before 2025.

Which will also delay the NB-IoT rollout.

Professor ten Hompel: First of all, NB-IoT is a global standard in its own right. It may be a part of 5G, but that doesn’t mean it has to wait for 5G. NB-IoT will introduce ultralowcost devices with long service lives into the Internet. We’re talking about highly scalable applications – virtually limitless numbers of devices that can be used in parallel to monitor and control logistics networks, for example. And that will be the first mass market for 5G.

So we don’t have to wait for 5G?

Professor ten Hompel: There are already tons of applications that we can implement with NarrowBand IoT – from smart key fobs to intelligent parking systems to global logistics networks. It’s a huge market opportunity – and I wouldn’t recommend missing it.

is the communications standard of the future and will likely be adopted starting in 2020. It connects not just people, but an enormous number of sensors as well. This capability enables the Internet of Things. With 5G, cars, heating systems and even trash cans will become network users with entirely different needs than fleshandblood users.
Deutsche Telekom launched its first NB-IoT service packages in summer 2017 and is rapidly expanding the availability of NB-IoT networks across its footprint. In Germany, it provides a streamlined NB-IoT device connectivity package as well as a more comprehensive product connectivity package known as NB-IoT Access & Cloud of Things.