| Summary: | 博士 === 國立中央大學 === 電機工程研究所 === 100 === The leading technologies specified in IEEE 802.16 standards have been evolved the most promising solutions in broadband wireless access networks. Having defined four types of service, the IEEE 802.16 standard still left the implementation of resource allocation supporting the four various qualities of service classes and admission control confining the number of flows entering the network as an open issue. Up to this point, however, this issue which has been touched and explored from time to time demonstrates that there is still room for much promotion. Thus, this study aims to explore dynamic bandwidth allocation algorithms in IEEE 802.16 time division duplex broadband wireless access networks under symmetric and/or asymmetric uplink and downlink traffic input, particularly in terms of accumulated throughput, fairness, and packet drop ratio in both infinite and finite buffer cases compared with others by simulations. The major results reveal that the proposed algorithm not only can provide much better fairness and maintain satisfactory quality of service support and high cumulative bandwidth but also in the case of the finite buffer depth is less buffer-consuming than the others, meaning that the hardware cost can be reduced by employing the proposed algorithm. In addition, a multiple cross-layer handover scheme using optimized MIH services in IEEE 802.16e networks is also involved. The thorough analyses of handover scenario show that the proposed scheme not only can reduce handover disruption time but also has no packet loss than the others. The two proposed solutions may help to compensate IEEE 802.16 standards for missing parts and to achieve seamless handovers in IEEE 802.16e networks, respectively.
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