A Fuzzy-based Mobility Prediction in the IEEE 802.16e

Abstract

Intersystem mobility having no awkward transitions or

indications of disparity, roaming across wireless access networks is

one of the main features of Mobile WiMAX. In this paper, we

propose a mobility prediction method based on fuzzy logic control

and an algorithm similar to the fuzzy c- mean partitioning to predict

the movement patterns and handover times by measuring mobile

users’ velocity and monitoring the received signal strength of the

serving base stations and target base stations simultaneously. With

the help of the prediction, reserving the required amount of

resources for the upcoming handover event at the target base station

can occur before handover initiation and execution. This would

grant mobile users of high priority connections (e.g., UGS based

VoIP connection) accessibility to the target base station with no

connection termination at various loading situations. The viability

and efficiency of the method is demonstrated through experiments

conducted with system parameters and propagation model defined

by WiMAX Forum. This is to show that the prediction of the future

handover times based on predicted received signal strength trend is

accurate to maintain the promised QoS level and to reduce the total

handover delays caused by layer-3 handover initiation. This allows

Layer-3 handover initiation to occur before Layer-2 initiation.