近年來因為寬頻的應用服務發展迅速，因此服務對於傳輸速度與品質要求就愈來愈高。所以WiMAX針對傳輸品質方面增加了QoS的要求，針對不同使用者或者是不同資料流採用相對應的不同優先順序，依照應用服務的要求，保證資料傳輸能夠達到一定的水準且能滿足應用服務的品質。

為了滿足QoS的需求，因此IEEE 802.16e提出五個不同的排程服務，當資料流進來時，首先會進入排程服務的分類，一開始就會將資料依照不同的需求做分類，分類的目的是要把資料流給予不同的QoS參數。在上傳排程演算法中，當SS與BS建立連線後會先在BS裡執行CAC檢查是否有足夠的頻寬給這個連線使用。一但允許連線後，BS scheduler將會依據用戶的所要求的頻寬分配給用戶，但分配到的頻寬不一定能夠滿足用戶的排程服務，因此用戶需要重新分配得到的頻寬分給正在準備上傳的排程服務。而本研究的重點在於如何分配現有的頻寬給正在準備上傳的排程服務，以達到非即時排程服務在即時服務多時不會飢餓與將在現有的頻寬下提高其效率。

因此本研究著重於將以提出的演算法做修改，利用NS-2模擬器來模擬WiMAX環境，並且套入修改前後的演算針對不同的評估參數做比較，以求能在不同的環境下，能比原本的演算法表現更傑出。

Because of the rapid development of broadband applications in recent years, the quality of service for transmission speed and quality is increased. Hence, the QoS requirement is added in WiMAX standard. Transmission priority depends on service types that users subscribe. This priority arrangement is to ensure data transmission and to meet the application service quality.

To meet the demand for QoS, IEEE 802.16e proposes five different scheduling services. When the data streams start to enter the scheduling queue, they will first be classified according to the service requirements. The purpose of classification is to provide different QoS parameters. In the Uplink scheduling algorithms, when a SS establish a connection with BS, BS will implement CAC to check whether enough bandwidth to use. Once the connection is established, BS scheduler will allocate appropriate bandwidth to users. However, the bandwidth assigned to the user may not be able to meet the scheduling service, so users need to re-allocate bandwidth to the schedule services. The goal of this study is to allocate available bandwidth to the schedule for uploading services to meet the non-real-time scheduling service. The proposed schedule method can prevent the non-real-time service from hungry and can enhance its existing bandwidth efficiency.

Based on the exist schedule method, this study attempts to propose a new algorithm to improve transmission efficiency. The NS-2 simulator is employed to verify our method. A comparison of network performance between the proposed method and exist schedule method is also given in this thesis

【中文部份】
[2] 唐雄燕，「無線寬頻存取技術及應用」，全華圖書，民96。
[3] 賴政凱，「在 NCTUns平台上模擬IEEE 802.16e Mobile WiMAX網路」，國立交通大學資訊科學與工程研究所，碩士論文，民96。
[4] 蔡明晃，「IEEE 802.16e 網路下鏈訊務跨層排程設計」，國立中央大學通訊工程研究所，碩士論文，民97。
[5] 楊佳祥，「IEEE 802.16e 及時通訊頻道品質感知的最大傳輸單元調整機制」，國立交通大學電機資訊學院資訊學程所，碩士論文，民95。
【外文部份】
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