Research On Vertical Handoff Technologies Of Heterogeneous Networks

With the development of the information technology, future wireless communicationsystem will contain all kinds of wireless access networks which have different coverageand different transmission delay. These networks and the new networks which put up forthe new demand will compose the next wireless communication system.The present handover technologies apply for single network but not suit for the futurewireless communication system. In order to hold true the trend of the next future wirelesscommunication system, vertical handover is put forward.The vertical handoff take the ideaof "union control"，the determining factors of the vertical handoff not only signal intensitybut also coverage area, network load, service band width and so on. Considering theimmature of the current vertical handover in heterogeneous networks, the article proposesa purpose vertical switching algorithm based on adaptive. The purpose vertical switchingalgorithm based on adaptive absorb the excellent switching performance of AHP and avoid"table tennis effect" effectively of DW, this algorithm, through setting higher priority foruser preferences network, achieves accessing purpose network instead of optimalperformance network. The emulation result indicates that this algorithm could access thepurpose network according to user preferences and get good switching performance.