Mobile Networks

In the course of the development of the 5th generation of the mobile radio standard 3GPP, significant innovations were introduced. The most notable innovations are the flexible scalability of the physical transmission layer, the use of frequencies in the millimeter range and the revised design of the core network. The physical layer of the 5G standard enables symbol durations of different lengths, which means that a wide range of applications with extreme requirements in terms of latency and data throughput can be supported. By using higher frequencies in the millimeter range, it is possible to use significantly higher bandwidths and achieve a much higher data throughput. However, this is only possible by using multiple-antenna systems with a large number of antennas, which require a fine-granular control. All system functions have been redefined in the core network, new concepts such as the separation of control and data plane and virtualization have been implemented, and the core network can integrate various wired and wireless access technologies.

In the field of mobile communications networks, the CEL investigates the system context of mobile communications, i.e. how modern communications algorithms can be integrated into the system, how the necessary data for operating the algorithms can be provided, what interactions there are in the overall system and how the network architecture must change, to support these algorithms. The following subject areas receive special attention.

Optimization of wireless networks and communication systems using machine learning

In the context of 5G, the (standardized) use of AI algorithms in mobile networks was discussed for the first time. At the CEL, we are researching how communications engineering processes can be improved using AI algorithms, e.g. channel coding or channel equalizers. On the other hand, we research how the operation of mobile networks can be optimized with the help of AI algorithms, e.g. mobility processes or communication protocols. In addition to the actual algorithms, we examine how the necessary data can be collected and stored.

Dynamic and self-optimizing wireless networks

With the constantly increasing demand on mobile networks, the structures and methods used are also becoming more and more complex, which means that the operation and optimization of the network has to be automated and adapted to the application scenario. For this purpose, the CEL is investigating how the mobile network can dynamically adapt to the requirements, e.g. flexible topologies (drone-supported networks) and resilient structures both in the radio access network and in the core network.

Multi-modal communication and information processing systems

Cellular networks are now more closely linked to specific applications, e.g. automobiles or IoT. As a result, information from different domains apart from mobile communications becomes relevant, e.g. radar measurements or video recording. The CEL investigates how this information can be used to optimize the operation of a mobile network jointly with the application layer, e.g. in the automated remote control of robots.

Integration of communication and cyber-physical systems

With the 5G standard, applications that have extreme requirements in terms of latency and reliability were also given greater consideration. In addition to the quality of service on the radio interface, the integration into the entire mobile radio system, including the core network and the application, is of essential importance, because latency and reliability are dominated by the "weakest" link in the overall transmission path. The CEL is researching how the integration of the various mobile radio domains with applications or end-to-end requirements can be implemented.