Handover in Mobile Wireless Communication Network - A Review

Mobility is the characteristics of mobile communication that makes it irresistible by all and sundry. The whole world is now engaging in wireless communication as it provides users\u27 ability to communicate on-the-go. This is achieved by transferring users from a radio network to another. This process is called handover. Handover occurs either by cell crossing or by deterioration in signal quality of the current channel. The continuation of an active call is a critical characteristic in cellular systems. Brief overview of handover, handover type, commonly used handover parameters, some methods employed in the literature and we present the convergent point for furtherance in the area of mobile wireless communication Handover

A fuzzy-based QoS Maximization protocol for WiFi Multimedia (IEEE 802.11e) Ad hoc Networks

The Quality of Service (QoS) management within a multiple-traffic Wi-Fi MultiMedia (WMM) ad hoc network is a tedious task, since each traffic type requires a well determined QoS-level. For this reason, the IEEE Working Group has proposed the IEEE 802.11e Enhanced Distributed Channel Access (EDCA) protocol at the MAC layer of WMM ad hoc networks. However, several studies have shown that EDCA must be further improved for three main reasons. The first reason is the poor performance of EDCA under high traffic conditions due to the high collision rate. The second reason is the need to maximize the traffic performance (delay, throughput, etc.) guaranteed by EDCA, seen the rapid evolution of the applications (multimedia, real time, etc.). The third reason is the need to maximize the energy efficiency of the EDCA, seen its use in battery constrained devices (e.g. Laptop, Smart phone, Tablet computers, etc.). For these three reasons, we propose in this paper a Three-in-One solution MAC protocol called QoS Maximization of EDCA (QM-EDCA), which is an enhanced version of EDCA. Based on the fuzzy logic mathematic theory, QM-EDCA incorporates a dynamic MAC parameters fuzzy logic system, in order to adapt dynamically the Arbitration inter frame Spaces according to the network state and remaining energy. Simulation results show that QM-EDCA outperforms EDCA by reducing significantly the collision rate, and maximizing traffic performance and energy-efficiency. In addition our solution is fully distributed

A Fuzzy-based mobility prediction in the IEEE 802.16e

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 basedVoIP 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

A Fuzzy-based Mobility Prediction in the IEEE 802.16e

Intersystem mobility having no awkward transitions orindications of disparity, roaming across wireless access networks isone of the main features of Mobile WiMAX. In this paper, wepropose a mobility prediction method based on fuzzy logic controland an algorithm similar to the fuzzy c- mean partitioning to predictthe movement patterns and handover times by measuring mobileusers’ velocity and monitoring the received signal strength of theserving base stations and target base stations simultaneously. Withthe help of the prediction, reserving the required amount ofresources for the upcoming handover event at the target base stationcan occur before handover initiation and execution. This wouldgrant mobile users of high priority connections (e.g., UGS basedVoIP connection) accessibility to the target base station with noconnection termination at various loading situations. The viabilityand efficiency of the method is demonstrated through experimentsconducted with system parameters and propagation model definedby WiMAX Forum. This is to show that the prediction of the futurehandover times based on predicted received signal strength trend isaccurate to maintain the promised QoS level and to reduce the totalhandover delays caused by layer-3 handover initiation. This allowsLayer-3 handover initiation to occur before Layer-2 initiation