A Threshold Based Handover Triggering Scheme in Heterogeneous Wireless Networks
Abstract: The widespread
popularity of Wireless Local Area Network (WLAN) is recognized as an effective
approach to complementing cellular networks for the high data rate and cost
effective connectivity delivered to mobile users. Efficient handover and offloading
schemes for integrated WLAN and cellular networks, referred to as Heterogeneous
Wireless Networks, have thus attracted lots of attentions from both academia
and industry. This paper proposes a novel Multiple-Threshold based Triggering
(MTT) scheme for Cellular-to-WLAN handover control. Aiming at minimizing the
probability of handover failures and unnecessary handovers, three thresholds
are calculated based on a variety of network parameters such as system
performance requirements, radius of the WLAN coverage, user mobility and
handover delays. The thresholds are then compared against the predicted user
residence time and estimated channel holding time inside WLAN to make vertical
handover decisions (VHDs). Simulations were carried out to evaluate the effectiveness
of MTT and results show that MTT minimizes handover failures and avoids
unnecessary handovers in integrated cellular and WLAN networks, thus providing
satisfactory Quality of Service (QoS) to users and improving system resource
utilization.
Keywords: integrated networks,
vertical handover decision, handover failures, unnecessary handovers, QoS
Author: Liming Chen, Qing Guo,
Zhenyu Na, Kaiyuan Jiang
Journal Code: jptkomputergg140027
