在IEEE 802.16中，排程的機制是根據基地台的下行（Downlink）及上行（Uplink）排程器進行通道頻寬的分配，依照排程決定每個訊框的通道資源需要替哪些連線進行資料服務，將結果放入DL_MAP及UL_MAP訊息之中，並且透過DL_MAP和UL_MAP訊息，告知所有網路中的用戶端（SS）在此訊框中通道資源的分配情況，各用戶端依據分配情形進行相對應的Burst接收及傳送動作。在傳統的頻寬資源配置方式，通常是對已經在佇列內等待的封包作為分配依據，分配時間點只考慮排程器在完成計算DL_MAP及UL_MAP訊息之前，當此訊框頻寬未完全配置時，其餘時間系統是處於等待的情況。但封包的到達是一種連續的行為，所以在進行Burst傳送及接收時，封包還是陸陸續續地到達各連線佇列中，但這些封包卻不能即時的得到處理，需等待到下一個訊框，為了考慮改善這個問題，我們提出一個解決方法。

在本篇論文，我們將依據傳統的頻寬配置方式，先對於在排程時間已在佇列等待的封包進行分配及排程，當訊框還有剩餘的頻寬可供使用時，我們提出累計平均到達率來估測到達封包大小的方式，並依照不同品質服務的等級而給予不同分配比率，對這些剩餘頻寬再進行一次分配的動作，以期減少封包在佇列內的等待時間，增加封包的有效性。

In IEEE 802.16 system, the bandwidth is allocated by the Downlink & Uplink scheduler. All Subscriber Stations know when they should send or receive by DL_MAP and UP_MAP. For most existing schedulers, the bandwidth is allocated using the minimum reserved rate maximum sustained rate. If the allocated bandwidth of one queue has reached the maximum sustained rate, there will be no more bandwidth given to it. However, for some light loaded system, there may be some free slots left after the scheduler assigns slots to all packets in queue. Those packets arriving after the scheduling will wait until next frame although there are free slots available. So, we can allocate those free slots to these arriving packets beforehand.
For this, we propose a new allocation method in this thesis.
In this thesis, we divide the allocation work into three rounds. In the first round, the slots are allocated orderly based on maximal sustained rate of each queue. In the second round, the left slots are allocated by Round Robin. If there are free slots left in this frame, the packets in all service queues have been assigned slots after this round. Then, the third round can be continued. For this round, a method for forecasting the packet arrival rate is proposed. Then, the left slots are assigned according to the forecasted arrival rate of each queue. Comparing to other protocols, there is one more round in our protocol. Those packets sent by this round can be delivered almost one frame earlier. This can decrease the average delay of the network and improves its performance clearly.

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