Study On Channel Allocation Algorithms Based On Handoff Prioritization

Handoff is a key element in mobile communication networks in order to provide Quality of Service to the system. The current handoff technology could temporarily meet the demand of the conventional wireless communication system, however, with the rapid development of highway and railway system in recent years, the increasing velocity of mobile terminals (MT) resulted in frequent handoffs between adjacent cells. And also, the utilization of microcell and picocell, which is used to expand the capacity of the system, further leads to frequent handoffs. Therefore, handoff technology is confronted with new challenges. Since the channel allocation algorithm contributes a lot to the performance of handoff procedure, it is of significant importance to further investigate the channel allocation problem.This thesis analyses the existing channel allocation algorithms based on handoff prioritization in wireless cellular networks, and is concerned with MTs'mobility pattern based channel allocation algorithms. The work consists of four parts:1) Call admission control in channel allocation algorithms;2) The effect of MTs'mobility pattern and the traffic load of the network on predictive channel reservation scheme;3) Optimal pre-reservation area size decision algorithm;4) The improvement of predictive channel reservation (PCR) scheme;The innovations in this thesis as bellow:1) Guarded channel - predictive channel reservation (GC-PCR) scheme;2) GC-PCR based channel allocation algorithm.The numerical results show that channel allocation algorithm based on GC-PCR scheme could significantly reduce the probability of dropping handoffs compared with PCR scheme, and verify that channel allocation algorithm based on GC-PCR scheme could improve the performance of the handoff procedure under certain conditions.