Akademik Veri Yönetim Sistemi
Computer Networks, cilt.284, 2026 (SCI-Expanded, Scopus)
Handover failures and service interruptions remain critical challenges to seamless mobility in Fifth Generation and beyond (B5G) heterogeneous cellular networks (HetNets). In these environments, ultra-dense deployments and coexisting Radio Access Technologies (RATs) dramatically increase the complexity of mobility control. User Equipment (UE) frequently switches between macro cells, small cells, and different RATs. These frequent switches introduce risks of service disruption, excessive signaling overhead, and degraded user experience. Therefore, Handover Management (HOM) has become one of the most critical functions in modern mobile networks. This paper presents a comprehensive survey of HOM techniques designed to support seamless mobility in B5G HetNets. The survey begins by reviewing the handover mechanisms defined in recent Third Generation Partnership Project (3GPP) releases, from Release 15 through Release 18. Their operational principles and practical limitations in dense multi-tier cellular architectures are discussed. The survey then examines existing mobility optimization methods, including parameter tuning, mobility robustness optimization, and coordinated mobility control. Particular attention is given to intelligent Mobility Management (MM) approaches based on Machine Learning (ML). These approaches enable predictive mobility analysis, adaptive handover parameter adjustment, and context-aware decision-making in large-scale radio access networks. The role of Software Defined Networking (SDN) in enabling centralized and programmable handover control is also analyzed, along with joint SDN and ML frameworks that support self-optimizing network behavior. The survey further examines how emerging technologies may shape future MM frameworks. These technologies include Integrated Sensing and Communication (ISAC), Reconfigurable Intelligent Surfaces (RIS), Non-Terrestrial Networks (NTN), and Integrated Access and Backhaul (IAB) architectures. Several open challenges are also discussed. These include the scalability of mobility prediction algorithms in dense deployments, security management during handover procedures, and latency constraints for Ultra-Reliable Low-Latency Communication (URLLC) services. Finally, the survey outlines important research directions for future mobility-aware network architectures in B5G and Sixth Generation (6G) cellular systems. This survey reveals that while ML-based and SDN-assisted approaches offer significant gains in handover robustness, critical gaps remain in real-time deployment, scalability, and security-aware mobility design for next-generation networks.