Self-optimisation of Vertical Sectorisation in a realistic LTE network

Vertical Sectorisation (VS) is a feature that exploits the capabilities of Active Antenna Systems (AAS) to improve service performance and network capacity, by splitting a single cell into an inner and outer sector. The attained gains primarily depend on the suitable and timely (de)activation of VS in response to the observed/estimated traffic distribution within the cell, while further gains can be achieved by properly adjusting VS parameters such as the transmit power distribution. Considering a realistic LTE (Long Term Evolution) network environment, in this paper a SON (Self Organizing Network) algorithm is proposed and evaluated, which dynamically (de)activates the VS feature and sets the transmit power split. The results show that the (de)activation of VS through a suitably tuned SON algorithm achieves significant throughput gains, while the dynamic adaptation of the transmit power distribution is mostly beneficial when operating in interference-limited environments.