A SON Function for Steering Users in Multi-Layer LTE Networks Based on Their Mobility Behaviour

In cellular networks, users that make frequent handovers and have a low time-of-stay in a cell (i.e., highly mobile users) might have a negative impact on the network performance. Furthermore the Quality of Service (QoS) experienced by these users might be low. This paper introduces a Self-Organising Network (SON) function, called the High Mobility SON function, that aims at reducing the amount of short stays in a multi-layer Long-Term Evolution (LTE) network. It does this by predicting the mobility behaviour of currently active users based on measurements, which were collected by users that were active in the past. Based on these predictions, the SON function aims at refraining from handovers to cells in which the user is likely to stay for a small amount of time, and at steering the user more appropriately. To assess the ability of the SON function to achieve its goals, simulations were performed in a scenario in which both macro and micro cells are deployed. Results show that the developed SON function is able to reduce the number of handovers by 17-23% and the number of short stays by as much as 43-49% at the cost of reducing the spectral efficiency by 13-15%.