Velocity-Aware Handover Management in Two-Tier Cellular Networks

TL;DR

This paper introduces a velocity-aware handover management scheme for dense two-tier 5G networks that reduces handover rates and maintains throughput by selectively skipping handovers and employing cooperative base station services.

Contribution

It proposes a novel handover skipping scheme that considers user velocity, along with cooperative base station techniques, to improve network performance in dense cellular environments.

Findings

Handover skipping reduces handover rates significantly.

Cooperative BS service compensates for skipped handovers.

The scheme improves coverage probability and user throughput.

Abstract

While network densification is considered an important solution to cater the ever-increasing capacity demand, its effect on the handover (HO) rate is overlooked. In dense 5G networks, HO delays may neutralize or even negate the gains offered by network densification. Hence, user mobility imposes a nontrivial challenge to harvest capacity gains via network densification. In this paper, we propose a velocity-aware HO management scheme for two-tier downlink cellular network to mitigate the HO effect on the foreseen densification throughput gains. The proposed HO scheme sacrifices the best BS connectivity, by skipping HO to some BSs along the user's trajectory, to maintain longer connection durations and reduce HO rates. Furthermore, the proposed scheme enables cooperative BS service and strongest interference cancellation to compensate for skipping the best connectivity. To this end, we consider different HO skipping scenarios and develop a velocity-aware mathematical model, via stochastic geometry, to quantify the performance of the proposed HO scheme in terms of the coverage probability and user throughput. The results highlight the HO rate problem in dense cellular environments and show the importance of the proposed HO schemes. Finally, the value of BS cooperation along with handover skipping is quantified for different user mobility profiles.