A dimensioning method for the LTE X2 interface

A central objective in designing LTE networks was to provide a better quality of experience for the end user. One of the implemented enhancements is a direct connection between neighbouring eNodeBs through the X₂ interface. This interface enables mobility management and the transfer of the user´s data in case of a handover. The aim of this paper is to provide an analytical model to dimension the X₂ link bandwidth under certain performance objectives. We take into account radio interface conditions in order to establish handover rates and we use the Kaufman-Roberts formula to compute the needed X₂ bandwidth. We also study the impact of traffic management schemes (admission control and QoS differentiation) and of transport protocols on X₂ dimensioning.