Improving coverage and load conditions through joint adaptation of antenna tilts and cell selection rules in mobile networks

One major topic of research into SON technology is the coordination of SON use cases. Network operators expect a coordinated handling of the parameter and configuration changes submitted to the operating network by closed-loop SON use case implementations. Beside a published conceptual framework, SON coordination has already been treated in the literature, especially regarding the mobility load balancing (MLB) and mobility robustness optimization (MRO) use cases. In this paper, we utilize the capacity and coverage optimization (CCO) and MLB use cases. Rather than performing any heading or tailing coordination of separate CCO and MLB algorithms, in our work we concentrate on the optimization considering both use cases in a joint algorithm. Our approach introduces cell-individual loads and the joint treatment of cell selection policies and antenna tilt settings into well-known and previously reported optimization concepts. Using system simulations of a sample LTE real deployment scenario, we verify that our joint optimization of antenna tilts and cell selection rules including the notion of cell-individual loads outperforms the optimization of tilts-only (with and without the notion of cell-individual loads within the algorithm) and of the cell selection rules-only in terms of spectral and energy efficiency.