Reduction of core network signalling overhead in cluster based LTE small cell networks

Small cell network strategies are applied for providing enhanced coverage and maximizing system capacity in the network. In such an environment, substantial growth of signalling load on the Core Network (CN) can be caused by reduced cell size, increased user density and increased user velocity. In this paper, in order to reduce the signalling load incurred by path switching operations in the small cell network, a new mobility control function, termed the Small Cell Controller (SCC) is introduced to the existing Base Station (BS) on the Radio-Access-Network(RAN)-side. Within a cluster, a designated SCC controls and manages a group of small cells and maintains associated forwarding information for UEs within a localized mobility management domain. When compared to the legacy scheme in the 3GPP, our simulation results show that the proposed RAN-side SCC is able to achieve the signalling reduction gain by up to 58.1% on the CN.