Enhancement of handover decision in heterogeneous networks

The next generation wireless systems (Fourth generation (4G) systems) are being devised with the vision of heterogeneity in which a mobile user/device will be able to connect to multiple wireless networks (e.g., WLAN, cellular, WMAN) simultaneously. Heterogeneous wireless networks have twofold perk of allowing the mobile users to benefit simultaneously from the merits of different wireless technologies. For example, IP-based wireless broadband technology such as IEEE 802.16/WiMAX (i.e., 802.16a, 802.16d, 802.16e, 802.16g) and 802.20/MobileFi is an add-on to existing 3G mobile technology, 802.11-based WLANs, 802.15-based WPANs. Heterogeneous wire-less systems will achieve efficient wireless resource utilization, seamless handoff, global mobility with QoS support through load balancing and tight integration with services and applications in the higher layers. In order to have the combined benefits of each and every deployed radio access technologies, a feasible vertical handover mechanism is foremost step that needs to be done [1]. A stalwart vertical handover mechanism inculcates various aspects needed for an efficient handover in the form of context aware metrics. The multifariousness of context metrics that these access technologies offer have a direct impact on perceived Quality of Service which is critical during network selection process. The detailed work of network selection process is presented here with initial setting of various threshold values of every parameter used in context aware metrics and that the algorithm is tested for real life scenarios of critical QOS situations such as overloaded wireless traffics.