12th International Congress on Ultra Modern Telecommunications and Control Systems ICUMT 2020, Brno, Çek Cumhuriyeti, 5 - 07 Ekim 2020, ss.1-4
In ultra-dense networks, an enormous number of
small base stations (BSs) are required to be deployed, and the number of
handovers (HOs) in heterogeneous networks (HetNets) increases as a result.
Mobility management with the increasing number of HOs is a critical issue that
requires uninterrupted connectivity due to user mobility in HetNets. However,
some BSs in the network may be more heavily loaded than their neighbors. Load
balancing (LB) involves load transfer from an overloaded BS to an under-loaded
neighboring BS for the more load-balanced network. HO and LB are two important
issues to improve network performance. In this paper, we propose an algorithm
that utilizes user speed and received signal reference power to adapt HO margin
(HOM) and time to trigger (TTT). Besides, the proposed algorithm balances the
loads among neighbor BSs. Additionally, the proposed algorithm aims to reduce
ping-pong HOs (HOPP) and HO failure (HOF) ratios. The simulation results show
that the rates of HOPP and HOF are significantly reduced by the proposed
algorithm, thus improving network performance under various mobile speeds.
Moreover, the results show that the proposed algorithm minimizes the standard
deviation of BS loads in the network. The proposed algorithm achieves load
balancing and reduces overload during user mobility in HetNets. Therefore,
there is more than 60% improvement in terms of the HOF, and 63% more balanced
network is achieved with the proposed algorithm in the network.