無線網路有別於有線網路最主要的原因為其通道具有時變性以及位置相關性的通道頻寬變動。有鑒於與日俱增的影音多媒體軟體和即時性互動式服務應用於無線環境之上，如何因應隨著時間和地點改變的頻寬特性來達到這些即時性服務所需要的多樣化服務品質保證就成為一個很重要的課題。
　　本論文提出之二階排程方法（TSQA）即為了解決上述之問題，我們在第一階段排程中針對各類型服務所要求的頻寬、延遲、封包遺失率等效能參數並考慮目前網路流量來動態配置其所需之頻寬，接著在第二階段排程中則針對每個行動主機考慮通道頻寬變動情形所推論得的頻寬使用最佳化問題以及主機間頻寬分配之公平性問題加以研究，以達到所需求的服務品質保證，最後再透過權重的調整來配置每個主機可得到的時槽數目。採用二階排程之優點在於不需要將每個資料流以一個佇列來管理，亦不需要額外的服務暫存器來作為補償的機制，如此可以減少系統中的佇列數，節省記憶體的使用量，而因為分開考量了服務品質保證和通道頻寬的變動，亦有效的降低了系統在排程時的複雜度。
　　最後我們透過模擬真實環境下的時槽多工無線網路，觀察在不同的網路情況下使用此排程方法的結果，並透過數學分析證明我們所提出的方法的確能有效地保證即時性服務在無線網路下的服務品質需求。

　　The main difference between the wire and wireless networks is the time-varying and location-dependent channel condition. With more and more multimedia applications and real-time services run on the wireless environment. How to support their quality of service (QoS) guarantee in dynamic channel condition has become an important issue.
　　This thesis presents a two-stage queuing approach (TSQA) to solve the problems mentioned above. In the first stage, we consider the required packet delay, bandwidth, packet lose and input rate of each class as parameters to allocate their required resource. In the second stage, we consider the channel condition of each mobile host, to achieve the optimal bandwidth utilization and fairness between hosts. And by adjusting the weight of each host queue, we can allocate required time slots for them. The advantage of using two-stage queuing approach is that, it needs neither a queue to be allocated for each flow nor any extra servers for compensation. In this way, the queue number as well as the memory size of system can be reduced. In addition, the scheduling complexity is reduced because we consider the QoS and channel variation problems separately.
　　Finally, through the mathematical analysis and simulation results, we can confirm that the TSQA can support the QoS requirements of real-time services in the TDAM wireless networks.

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