Mobility robustness improvement through transport parameter optimization in HetNets

In order to improve the mobility robustness in heterogeneous networks (HetNets), a series of transport parameter optimization schemes are proposed in this paper. The HO parameters, including TimeToTrigger, A3-offset and Hysteresis are adaptively adjusted based on the type of the source cell and the type of the target cell. So as to achieve accurate measurement results, thus improving the HO performance, the Layer 3 (L3) filter coefficient is also optimized by adaptively adjusting its value with different UE speeds. Simulations are performed and results show that the proposed schemes behave well in HetNets and can help improve the mobility performance with respect to handover failure (HoF) rate and short time-of-stay (ToS) rate. As a small step towards mobility robustness optimization, the proposed schemes in this paper shine light on further study on transport parameter optimization in HetNets.