IEEE 802.16 是新一代的無線寬頻網路存取技術，用於解決骨幹網路的最後一哩頻寬不足以及高設備成本的瓶頸。隨著現代越來越多元的網路，應用程式日新月異，WiMAX將網路應用程式分類為五個不同的等級，IEEE允許各家網路提供者自由的設計排程演算法，WiMAX的排程機制也被廣泛的討論，但是在WiMAX standard中並未詳細定義關於允入控制 (call admission control)以及封包排程 (packet scheduling)的相關機制。
本篇論文提出一個新的演算法:” Hybird Quantum-based Priority Scheduling Algorithm (HQPS)”，應用於WiMAX MAC layer的允入控制以及封包排程。HQPS主要是解決無線網路中頻道干擾的問題以及滿足不同連線的QoS需求。當一個連線進入系統後，我們使用了一個共用的傳輸佇列來存放所有連線的封包，而其中也包涵了重新傳送的封包，接著依照packet的服務類別以及頻道狀況決定封包的priority。在頻寬分配的部份，我們使用一個二層式的網路資源分配演算法來滿足各個連線的需求，第一階段藉由limited quantum的分配方式，以滿足各個連線的最小保證頻寬，第二階段再依照packet priority分配剩餘頻寬。
我們使用了qualnet模擬器來驗證我們的演算法效能，我們對於網路上不同服務類別的組合分別進行模擬，而實驗結果顯示，我們的方法可以在封包遺失率、系統頻寬利用度以及average throughput方面都有相當好的成效。

IEEE 802.16 version of the Worldwide Interoperability for Microwave Access (WiMAX) standard represents a new generation technology for high speed Broadband Wireless Access system. Its primary function focuses on resolving the bottleneck of lack of bandwidth and excessive equipment cost occurred in the last mile of communication systems. Due to the diversity of modern network systems and their applications, five service types are defined in the standard to support for different Quality of Service in the system. IEEE allows WiMAX vendors the freedom to design scheduling algorithms to achieve the efficiency of allocating network resources. Several scheduling algorithms have been proposed for WiMAX system. However, some performance drawbacks of these algorithms indicate that there are plenty of rooms for improvement.
In this work, a new packet scheduling algorithm – Hybird Quantum-based Priority Scheduling (HQPS) Algorithm was developed for Call Admission Control of the WiMAX MAC layer. A single transmission queue was designed for the storage of all connection’s packets including retransmission packets. Sorting priorities were defined according to service classes of the packets. For bandwidth allocation, a two-tier calculation method was used for resource allocation. Limited Quantum Allocation was used in the first phase of the method to allocate resource to the minimum reserved rate of each connection. The remaining resource then allocated from the highest priority to the lowest in the second phase.
Qualnet simulator was used to evaluate the performance of this new scheduling algorithm. Various scenarios were tested. Simulation results verify the improvement of the efficiency in packet lose ratio, system utilization, and average throughput.

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