Application of intra-RAN flexible spectrum use for network capacity management

Spatial and diurnal variations on the user distributions over the cell and network areas present challenges to the network architecture design since the capacity of the network should follow the varying traffic distributions. Necessary flexibility can be provided with new network architectures based, e.g., on relays or distributed antennas. In this paper, an alternative, or possibly complementing, approach is introduced. Each radio access network (RAN) is assumed to contain both wideband (WB) and narrowband (NB) carriers. Intra-RAN flexible spectrum use is considered within one RAN between its WB and NB carriers, to provide flexibility between higher capacity offered for the hotspots by the WB carrier and larger coverage offered by the NB carrier. For the flexible spectrum use, three different intra-RAN carrier exchange scenarios are introduced and their performance is compared to the one of fixed carrier assignment with multiple real-time and non-real-time services. The results indicate that even though WB carrier has the ability to provide high data rates, better overall performance can be achieved if flexible NB and WB carrier exchanges are used to adapt the network to the changes on the user distributions.