Evaluation of adaptive active set management for multi-connectivity in intra-frequency 5G networks

Improved throughput and reliable communication that is free of mobility failures are some of the requirements for 5th Generation (5G) mobile networks. One of the cost-effective solutions to meet capacity requirement is standalone ultra dense network that use the same spectrum and a cloud radio access. However, stand alone ultra dense networks are prone to mobility challenges. Previous work proposed and evaluated multi-connectivity that co-ordinates transmission on both the user plane and control plane; this enables improvement not only in throughput but also in mobility robustness. One of the major component of multi-connectivity is managing the "active set" which is the set of co-ordinating cells. Proper procedures for managing user-specific active set was defined for 3G Soft Handover. This paper revisits prior art schemes for active set management and proposes new adaptive one for 5G Networks. Performance evaluation is provided with the help of elaborated models for simulation. Among other things, it is shown that the adaptive active set management scheme reduces the signaling overhead associated to active set updates by around 19% compared to static active set management.