“What differentiates 5G from the earlier generations of mobile networks is that several different technologies will be able to get on together. This is why network architecture needs to be renewed,” says Di Yuan, Professor of Mobile Telecommunications in the Department of Science and Technology at Campus Norrköping.
In the future many objects will also be linked to the internet, and will communicate with each other via the “Internet of Things”. According to predictions, 50 billion units will be linked to the web by 2020.
Foto: Monica Westman Svenselius
“We will see completely new applications and new types of communications. 5G units can be placed in many different objects; the vehicle and transport sector is a good example of where great benefits can be achieved. This will lead to new business models,” says Professor Yuan.
New requirementsThis is why completely new requirements are being placed on the networks. Professor Yuan and his research team began research around what are called ‘heterogeneous networks’ in 2011. By combining the large base stations with small cells, which are responsible for high-speed data transfer over short distances, it is possible to build networks that can handle the intensive traffic at an airport, for example, or a large railway station. The research challenge is to optimise the networks – to ensure that the right cell handles the right traffic at the right moment – and to minimise the disruptions that arise when a large number of telephones, e-readers, reading tablets and computers are to share the space.
Heterogeneous networks are a good example of network architecture that can achieve the 5G target with 1,000 times greater transfer capacity. Another benefit is also the possibility of reducing energy consumption.
“Heterogeneous networks make it possible to separate functionalities where traditional base stations keep watch over a large area and small cells deliver data. Only those cells that have traffic need to be active, while the rest can go into standby. The system exists, but the challenge is to optimise the networks so that we can really take advantage of it.”
Horizon 2020 projectProfessor Yuan is also leading one of the EU 2020 Horizon projects, ACT5G, that is looking at heterogeneous networks of the future and also smart 5G networks.
That is to say, the network should understand what signal strength you need and will have in the immediate future. If you are out driving your car and, for example, you are approaching a tunnel the network will predict in advance that your coverage is going to deteriorate. More data will then be sent to your unit's data buffer so that you do not experience any disruption in the tunnel. This naturally means that it must be possible to analyse large quantities of data in real time.
It is common at present for several operators to share one mast, but in the future they will also be able to share network capacity, in real time, and dependent on need. It must therefore be possible to divide up the capacity dynamically so that available resources – bandwidth and signal strength – may be used in the most efficient way possible.
ACT5G is a four-year Marie Sklodowska Curie project, which means that the project involves research exchange and training of PhD students.
In addition to Professor Yuan’s group at LiU, researchers at Politecnico di Milano in Italy and Alcatel Lucent – Bell Labs in Stuttgart in Germany are also involved. The University of Maryland in the United States is another collaboration partner.
“We employ two PhD students here and two in Milan, and they will be working together in places such as Alcatel Lucent’s laboratory in Germany. Our experience is that research in Marie Sklodowska Curie projects is a very good way to integrate knowledge and to create synergies between the research groups,” Professor Yuan says.
The project will begin on May 1, and recruitment of PhD students is in full swing. Interest is great; more than 70 hopefuls have registered their interest so far.
LiU research for super-fast 5G, LiU News about 5G research at LiU
EU money flooding in, LiU News on Horizon 2020
LiU researchers untangle Stockholm traffic, LiU News about Di Yuan’s research team
Mobile Telecommunications group