Affiliations: [a] Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology, Yunlin, Taiwan
| [b] Department of Electrical Engineering, National Yunlin University of Science and Technology, Yunlin, Taiwan
Correspondence:
[*]
Corresponding author. Kuang-Hui Chi, Department of Electrical Engineering, National Yunlin University of
Science and Technology, 123 University Road Section 3, Douliu, Yunlin County 64002, Taiwan. Tel.: +886 5 5342601/Ext. 4245; Fax: +886 5 5312065; E-mail: chikh@yuntech.edu.tw.
Abstract: Handoff decision is an important issue governing the perceived quality of service by a mobile terminal. This study aims to provide a handoff scheme leveraging a Kalman filter combined with a fuzzy system that is intended for a UE (user equipment) to carry out while roaming among different radio access technologies. Handoff decision is made in light of UE-discovered information such as RSS (received signal strength), data rate, network latency, and user preference as input criteria. A Kalman filter is tasked to reduce noisy RSSs. Then a fuzzy inference engine fuses the filtered-RSSs with the remaining three metrics to deduce whether to launch handoff. UE movements within heterogeneous wireless networks are simulated with a symmetric random walk model. The Pascal’s triangle is applied to visualize UE’s mobility patterns as an elegant way. Simulation results show that the proposed scheme outperforms other approaches in terms of reducing unnecessary handoffs.
Keywords: Kalman filter, fuzzy system, handoff decision, random walk model, heterogeneous wireless network
