Dynamics of the flexible functional split selection in 5G networks

The architecture of the radio access network (RAN) in 5G features a functional split between centralized and distributed units, which can he leveraged to reduce inter-cell interference. Recent work proposes to dynamically adapt this split in accordance with the instantaneous interference situation experienced by all users. However, it is unclear whether performing this flexible adaptation is actually feasible, since the interference situation changes continuously as users move. In this work, we investigate the impact of mobility on the problem of dynamically selecting the optimal functional split. We employ a mobility simulator based on real street layouts and trace-derived traffic patterns to generate continuously varying interference situations. Then, we analyze how frequently the optimal functional split changes and how much the performance of previous splits differs from the new, optimal one. The results allow us to estimate the time required for a viable flexible functional split adaptation.