RAN-Core Convergence
With the adoption of centralized RAN solutions where complex Base Band Units are handling all the connectivity specific features, a new control plane functionality became necessary. It has to supply the functionality previously provided by the core networks within the specific interest and coverage area of the new centralized RAN functionality.
In this research item we study how to import and adapt the core network functionality within the RAN for the benefit of the local communication. It includes:
The dynamic network planning – centralization of the self-organized networks management functionality to adapt the specific deployment to the available spectrum and to the required resources. This is based on the new runtime flexibility in powering on/off of radio heads, in their spectrum allocation and power control. The network changes based on the momentary requirements.
Mobility management – allocation of beams to the devices according to their mobility pattern (speed, direction) considering highly overlapping environments (inter-RRH handovers due to radio resource availability) but still not complete (inter-RRH handovers due to coverage specifics). A careful attention is given to seamless inter-BBU handovers (even cell-free RAN has borders).
Radio resources scheduling management – a policy based mechanism of pre-defining how the different beams would be allocated towards the subscribers to avoid network congestions
Subscriber QoS management – assurance of the radio resources required to handle the specific QoS required by the subscriber (especially connectivity robustness while devices are moving through the environment).
Using the large experience accumulated in the development of 5G and 4G core networks, Fraunhofer FOKUS is developing a new near-real time radio interface controller (RIC) enabling this functionality and its coordination with the core network.