Split control plane functionality in millimeter-wave overlay access

The millimeter-wave band is a candidate to overcome the spectrum shortage in future mobile radio networks. As the coverage area of base stations operating at these frequencies is expected to be more limited than at the sub 6 GHz bands, they will supplement existing base stations instead of replacing them. With these additional small cells a split plane architecture becomes an interesting architectural candidate, where capacity is provided by the small cells while continuous connectivity is guaranteed as it is available today. The introduction of such a split between the control and the data plane introduces new options and degrees of freedom of system and protocol design that are investigated in this paper.