“…3) Data Aggregation: In large-scale systems, devices may be clustered in local area networks, which then connect to the core networks through a gateway or aggregator [151], [157], [164], [165], [166], [167], [168]. Instead of a traditional spatial clustering relying on geometric distances and/or energy-related measures [151], [157], [164], [165], [166], [167], a more advisable approach in the context of large-scale URLLC lies in jointly considering traffic profiles (both in terms of traffic intensity and performance requirements) and network dynamics. Interestingly, Orim et al [168] have initially proposed a priority-based spatial aggregation algorithm that gives priority to URLLC devices through power ramping in the physical random access channel.…”