| The increasing demand of accessing broadband Internet conveniently and rapidly has stimulated the development of broadband wireless access (BWA) technologies and made them a new hot topic in communication researches. IEEE 802.16e/mobile WiMAX network, with its various advantages such as perfect standardization, high-speed data transmission, wide service coverage, fast network deployment, easy system scalability, flexible network construction, etc., has become an ideal "last mile" wireless access technology of broadband metropolitan area networks. Mobile WiMAX network supports diversified multimedia services, including data, audio and video. However, this also results in severer conflict between limited resource and huge demand for data transmission in wireless communication system. Requirement for quality of service (QoS) differs among traffics. Under the circumstances of disadvantageous wireless transmission conditions and mobility of mobile station (MS), efficient resource management strategies to meet QoS requirements and maximize resource utilization become crucial. This dissertation addresses the resource management strategies with QoS guarantee in IEEE 802.16e/mobile WiMAX BWA networks. Withpoint-to-multipoint (PMP) network topology, the research focuses on the schemes of resource reservation, admission control and power saving for MS. The main contributions of this dissertation are as follows.1) A dynamic bandwidth quasi-reservation scheme (DBQRS) and the corresponding admission control policy are proposed to address the non-applicability of the two-phase activation model defined in IEEE 802.16e standard to real-time services. Based on the estimations of MS handover probability and the traffic arrival probability, bandwidth is quasi-reserved dynamically for real-time service flows. In the admission control process, non-real-time service flows can occupy the bandwidth quasi-reserved for real-time ones temporarily. DBQRS not only provides QoS guarantee for both mobile and fixed wireless real-time multimedia services in 802.16e networks, but also improves the fairness of admitting new and handover real-time service flows and enhances the bandwidth utilization.2) An efficient admission control scheme is proposed by relying upon IEEE 802.16e system's ability to support adaptive multimedia services. Traffics are prioritized in accordance with the characteristics of data delivery services defined in 802.16e standard. When the available free bandwidth in the target cell cannot meet the requirement of handover service flow, the bandwidth assigned to active service flows is decreased in ascending order according to the pre-set priorities and even the bandwidth requirement of handover service flow can be reduced, which would decrease handover service flow dropping ratio. All the free bandwidth can be used by either new or handover service flows, thus reducing the new service flow blocking ratio and utilizing the resource more efficiently.3) According to the characteristics of power saving classes (PSCs) and the properties of data delivery services, an efficient sleep mode management scheme is proposed for IEEE 802.16e system. With the precondition of guaranteed data transfer, the PSC parameters, sleep windows and listening windows, are designed. Moreover, the sleep windows of each PSC are maximized. Under the condition that the QoS requirements of traffics are satisfied, the proposed "PSC anti-expansion" mechanism makes the number of PSCs associated with MS as few as possible. The proposed scheme maximizes the unavailability intervals of MS. Consequently, the energy of MS is saved greatly. In addition, a universal theoretical analysis model to assess the saved energy is also designed for PSC-based sleep mode.
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