Upper bound analysis of the handover performance in HetNets

Handover in heterogeneous networks (HetNets) is an interesting research challenge that has attracted considerable attention in recent years, producing a variety of handover schemes that are difficult to compare because they differ in the considered assumptions and target user/network utility functions. Therefore, how much room is left for further optimization is quite unclear. In this letter, we propose a framework to derive an upper bound for the performance of handover in HetNets that can be used as a benchmark to compare different practical handover schemes. The approach computes the optimal handover strategy as a function of the user's speed, cell size, and load conditions, under the ideal assumption of non-causal knowledge of the channels from terminal and base stations. The proposed framework is then used to provide a comparative performance analysis among some existing handover schemes.