Mobility management and resource allocation are the key features of the current and next generation cellular systems that enable the users to change seamlessly their cell associations and maintain their service continuity with required quality-of-service (QoS). Software-defined networking (SDN) promises to overcome such adversities in network design by centrally controlling the behavior of the underlying network via an abstraction layer. These mechanisms are applied on those procedures in 5G mobile communications exploiting the holistic knowledge of the network.
In the first part of the thesis, we develop and examine the performance of the legacy 3GPP X2 handover (HO) using the OpenAirInterface (OAI) platform to understand not only the mobility management in 4G but also the interplay of system parameters on triggering the HO process towards designing a HO algorithm. As a next step, a load-aware HO decision algorithm for the next-generation heterogeneous networks (HetNets) is proposed considering the users' service delay and the asymmetrical cells power. Results have shown that the proposed algorithm outperforms the conventional received signal strength (RSS) and distance-based ones. In addition, an SDN architecture is sketched to manage the system decisions resulting in a centralized network coordination.