Day by day, billions of phone calls are made around the globe – but this particular one, on July 1, 1991 in the middle of the Finnish summer when Kaarina Suonio, the deputy mayor of Tampere, somewhere on a narrow neck between Lake Näsijärvi and Lake Pyhäjärvi, took the call by her prime minister, Harri Holkeri, went down in telecommunications history. It was the first-ever conversation using a commercial, fully digitized wireless telecommunications network that started a mobile communications revolution. All of us at one time or another have probably heard the network’s uninspiring official name: Global System for Mobile Communications, or GSM for short.
However, the GSM developers at that time were focused on telephone calls and less on wireless data transmission. Data rates of 9.6 Kbit/s make today’s kids burst into laughter. Having to wait nearly twelve weeks for a favorite movie to be downloaded sounds like the digital stone age – and that’s what it was from today’s perspective.
But with each new mobile communications standard the transmission rate picked up speed. While WAP technology at the end of the nineteen-nineties was still deprived of making a major breakthrough – WAP facetiously stood for “Wait And Pay” back then – cellphone users, thanks to UMTS (3G), in 2004 started surfing the network with 384 Kbit/s – a speed with which some are still stuck today. With 4G, the first wireless broadband internet, data can theoretically be sent back and forth at up to 1,000 Mbit/s. With 5G, the latest standard, it can be done even ten times faster.
99.999999999 % reliability
As a result, a host of all-new possibilities has been opening up for industrial production, for healthcare, in autonomous mobility, and in farming since 2019. In 2020, more than 20 billion machines or other devices worldwide were already connected to the network via the Internet of Things (IoT) – many of them by wireless communications. And now, while 5G is just being rolled out, the political, business and scientific communities are working on rolling out the next generation: 6G. In the coming decade, it’s supposed to be available across the board.
Peak transmission rates of 1,000 gigabits and real-time communication are the goal. 50 to 100 times faster than 5G. Constant connectivity at terabit speed. With visionary reliability of 99.999999999 percent. That’s the plan. Enabled by the utilization of higher frequencies from 100 to 300 gigahertz. For comparison: 5G uses frequencies from 22 to 60 gigahertz. So, is 5G obsolete before it has even been rolled out everywhere? “No,” says Professor Wolfgang Kellerer from TU Munich, the project leader of the 6G Future Lab Bavaria. “5G plays a vital role for Industry 4.0 and the Internet of Things, facilitating a new dimension of intelligent communication between machines.” However, he adds, “experience shows that it takes around ten years to develop a new wireless generation. To be ready for a big rollout in the early 2030s, those of us doing basic research want to work with the other key actors right from the start to lay the groundwork for success.” Because, says Kellerer, “6G will be human-focused.” Human-focused, what does that mean?
Possible applications for 6G
Automation and manufacturing
6G enables wireless applications where safety is imperative. This applies to cobots or remote-controlled cranes as well as to various types of production machinery. Machines and logistics chains benefit from the fast data transmission.
High-resolution holograms displayed via smartphones, extended reality (XR), in which real and virtual worlds combine, and digital twins that monitor real-world vehicles or machinery without time-related or spatial delays will develop further with 6G.
6G enables precise determination of the position of self-driving cars and commercial vehicles and distance measurements between the host vehicle and other vehicles, persons or obstacles in real time, plus a 360-degree view thanks to a variety of sensors gathering an enormous wealth of data that have to be shared simultaneously.
Thanks to 6G robots perform surgical procedures that are remote-controlled with millimeter-level accuracy by physicians. Using high-resolution monitors or mixed-reality headsets and with the help of 3D holograms, they can see exactly what’s happening inside the patient’s body. 6G is also supposed to enable wearable mini sensors that continuously monitor the vital signs of healthy persons and patients.
Reliability more important than speed
According to Kellerer, it’s about “a wide range of technologies integrated into our everyday lives that we interact with almost without thinking about it.” Humans and machines on “an equal footing” so to speak, so high reliability of the network is paramount, says Kellerer, explaining its importance, for example, in the context of using assistance robots in household settings or high-resolution 3D maps in autonomous vehicles. Because, thanks to 6G, the data signals arrive at the target device at lightning speed, the feasibility of time-sensitive artificial intelligence applications in particular can be expected to improve.
The crucial aspect here is the network architecture, which researchers at the Karlsruhe Institute of Technology (KIT) are exploring as well. “To serve as many users as possible simultaneously while transmitting large data volumes as fast as possible, the wireless networks of the future have to consist of numerous small cells,” explains Professor Christian Koos. This has the advantage that the data do not have to travel across long distances. “This enables the transmission of high data rates with minimal use of energy and low ambient electromagnetic emissions,” says Koos. Hundreds of gigabits per second on one channel can be transmitted between the individual cells.
5G and 6G in comparison
The network itself becomes a sensor
6G will be the first wireless communications generation where a whole host of sensors will be interconnected, for instance in robots, machines, household appliances and autonomous vehicles, or in cobots that can interact with human workers by means of sophisticated sensor technology. They’ve become firmly established in the world’s factory halls. Going forward, shorter response times will enable even more flexible collaboration between humans and machines.
To the interview
6G will be human-focusedProf. Wolfgang Kellerer,
Project leader of the 6G Future Lab Bavaria
The network itself can become a sensor as well, because specific information can be gained based on the radio signals, for instance whether an object is located between the transmitter and the receiver – with even greater sensitivity than the way in which Google Maps already works today. This sensor information is then supposed to be analyzed with the help of artificial intelligence in order to continuously optimize the 6G network, in other words to make the required output available in the right place at the right time.
Schaeffler is establishing test beds
Schaeffler, as well, is preparing for the myriad opportunities for which the rollout of 5G (and the prospects of 6G) creates the foundations. The company has already set up initial use cases in a test environment at its plant in Changwon, South Korea – an operation of self-driving robots, augmented reality and production facilities in an in-house 5G network. “5G technology – especially Release 18 to be launched in 2023 – is showing us major benefits compared to the current Wi-Fi 6 standard. It enables us to control and localize driverless transportation systems in real time by using one device. This eliminates the need for sensors and the related integration effort, in other words it reduces costs and time,” explains Christina Fischer from the Schaeffler Technology & Innovation Center in Herzogenaurach. But she cautions that the 5G Release 18 features that have been publicized would actually have to materialize. Fischer: “Only if they do will 5G be able to fully display its fortes, that is if latencies of 1 millisecond are possible in wireless data transmission. In that case, we’ll be able to use wireless transmission even for safety-critical and production-critical sensor data.”
All in all, the rollout of 5G as well as of 6G is a herculean task on which not only Prof. Kellerer and his team are working, as numerous 6G research and development activities are being pursued around the world. China and Tesla’s founder Elon Musk have sent the first 6G satellites into orbit for testing purposes. The German federal government is making 700 million euros available for 6G research until 2025. Scientists at TU Dresden are engaged in research work of the world’s fastest microchips that will be needed for 6G. South Korea has invested in a huge project aimed at launching 6G in 2028. Let’s see who will ultimately win the race in a hyper-connected world.
Future vision for Schaeffler plants in 2030
- Devices communicate on the Internet of Things with cloud-based artificial intelligence systems. Every machine becomes “smart” even without a dedicated high-performance computer.
- Industrial robots respond to their environment fast and reliably, plus fully autonomously (Advanced Robotics).
- With digital twins real-world manufacturing processes can be analyzed in real time by means of digital replicas.
- End-to-end communication with very low latencies across diverse networks is guaranteed.
- High energy efficiency of an adaptable, needs-based network enables sustainable manufacturing.