IEEE 802.16是一種無線寬頻網路標準，其具有較高的傳輸速率、較長的通訊距離，以及能支援語音、影像多媒體服務等特點。其中IEEE 802.16定義了五種服務品質(Quality of Service; QoS)來滿足各種需求。然而，在IEEE 802.16標準中並沒有將排程演算法作明確定義，所以這部分一直是開放給學者及通訊商來研究及探索。因此設計一個好的排程演算法來讓有限的頻寬資源能夠去滿足即時性與非即時性服務的需求是相當重要的。
本論文將會提出一個根據工作站所使用的調變及編碼方式(Modulation and Coding Scheme; MCS)，來安排其傳送優先順序的演算法，並透過限制各服務流的可用總頻寬來保證每一個服務流都有機會進行分配，另外，當遇到不同的工作站使用相同的調變及編碼方式時，我們將考慮其佇列長度，讓佇列長度較長者先進行分配。模擬結果顯示透過此種方式可以有效的增加總傳輸量，並且讓各個服務流都有基本的頻寬可使用。

IEEE 802.16 is a standard for wireless communication network. It has the advantages of high transmission rate, long transmission distance and supporting various kinds of multimedia services such as voice and video. For these services, IEEE 802.16 defines five classes for quality of service (QoS) which will meet a variety of data service demands. Nevertheless, IEEE 802.16 does not define the scheduling algorithm for these classes. This is left for researchers and communication suppliers to explore. Therefore, it is important to design a good scheduling algorithm to satisfy the requirement of real time and non-real time service.
In this paper, we will propose a scheduling algorithm which will sort the priority of subscriber station (SS) according their modulation and coding scheme (MCS). Then, we will restrict the total available bandwidth for each class to ensure the scheduled bandwidth of each class. Then, the queue length will be used to decide the priority when service flow uses the same MCS. The simulation result shows that the total throughput can be increased profoundly for the same load with our algorithm and the delay will be decreased relatively.

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