Call Admission Control In LTE/WLAN Heterogeneous Network Based On DS Evidence Theory

With the rapid development of wireless communication technology, there aremore and more types of business which users need. Wireless networks of the futurewill make full use of the complementary characteristics among different networks, torealize the mutual integration of networks and types of service. Heterogeneousnetwork is a typical form of integration of networks. LTE/WLAN heterogeneousnetwork, as a new generation, has great advantages in terms of coverage area and datarate, and great differences in terms of modes of resource allocation. More networks,more parameters, higher requirements of access control algorithm are put forward,and traditional algorithms are not applicable. So, in order to ensure the effectiveintegration of different networks, and to meet the needs of the development of mobilecommunication, it is particularly important to design an access control algorithmbased on the characteristics of LTE/WLAN heterogeneous network.In the paper, a new evidence combination rule based on Murphy rule is proposedthrough the research on the DS evidence theory. This rule has the advantage of bothMurphy rule and ER rule. Based on the pretreatment of the evidences, the improvedrule combines the evidences effectively without changing the Dempster rule itself.Examples show that the improved rule has obvious advantages in evidence focusingand convergence speed, which makes it especially suitable for scenes where there areonly a small amount of evidences.Aiming at the current problems in heterogeneous networks, such as too manyparameters which make it hard to balance, ping-pong effect and handover droppingcaused by frequent switching, combining with some problems unresolved in currentpapers, a heterogeneous network access control algorithm based on DS evidencetheory is proposed, including a network handover trigger algorithm based on locationinformation and a network selection algorithm based on DS evidence theory andanalytic hierarchy process. The user selects the network independently and report theresult to the network, then the network chooses some of the users to permit them toaccess. Meanwhile, to give new users more opportunities to access the network, anew evaluation standard of priority is proposed based on the user selection strategyaccording to priority, which can reduce the blocking rate effectively.Simulation results show that the algorithm has some certain advantages, whichachieves the expected goal of the paper.