Latency Minimization Techniques in Dense Urban 5G Mobile Networks

The advent of 5G mobile networks in environments with ultra-high density (e.g. city centres) poses unique challenges related to latency, arising from three main areas: user density, multipath propagation and limitations associated with supporting infrastructure. This paper provides a complete review of advanced latency reduction strategies tailored toward ultra-high density 5G environments. Key strategies that have been examined include; Edge computing, dynamic resource scheduling, slicing and intelligent handover techniques using machine learning. The study evaluated the performance of each latency reduction technique in effectiveness in reducing end-to-end latency considering a range of urban density scenarios); and used simulation-based performance. The contribution made by ultra-dense small cell deployments and millimetre-wave (Wave) communication towards improving latency performance has also been evaluated. Often hybrid methods combining the edge processing with real-time adaptive radio resource management produced overall measurable latency benefits matching ultra-reliable low-latency communication (URLLC) requirements. Finally the paper provides an outline of recommendations and implications to network operatives as well as future research pathways towards the development of real-time adaptive 5G systems within complex urban topologies.