在IEEE802.16 (WiMAX)下，有五種不同的服務品質連線需求，我們將各個有傳輸需求的連線考慮它們的平均抵達率，來建立在排程器中更準確的分配方式。由IEEE 802.16的標準制定中，UGS的頻寬要求量為常數，因此我們焦點就放在其餘四種連線：ertPS、rtPS、nrtPS、BE。
依負載定向排程法的程序，若在佇列中已有封包在等待傳送，對於各種服務我們根據以往的模擬結果來訂定基本配額，做完第一回合分配後，根據平均抵達率，定義所要的參數，設立一個做第二回合分配時的權重。假設在第一回合分配後連線佇列還有封包未傳送，才會參與第二回合的分配，藉此將剩餘頻寬做更有效的運用。
經由模擬測試，與輪替分配(round robin)方法比較時，能夠有效提升ertPS、rtPS的傳輸效率，減少封包延遲時間。

In IEEE 802.16, there are five different service flows for different QoS. In most of the foregoing researches, each class will request a bandwidth from the base station (BS) to satisfy its basic requirement. If there is bandwidth left after satisfying the basic requirement of all classes, the BS will use round robin, weighted round robin or some other protocol to schedule the remaining bandwidth.
Since the request may not always be the real demand, a lightly loaded class may request a high bandwidth by the shortage of information. The QoS may not be satisfied for a class with a high load. Therefore, we propose the scheduling of bandwidth should be load-oriented. In this paper, we use the round robin as a representative for scheduling without load orientation. We will show the performance of ertPS class will be a disaster in some situation even if it has the highest priority. Then, the weighted round robin will be used a representative for scheduling with load orientation in this paper. The BS will collect the average arrival rate of each class during operation and the result will be used to decide the weight of each class. The simulation result shows the performance of ertPS class will be improved regardless of its load for scheduling with load orientation. Then, we propose a formula to include the priorities for scheduling method with load orientation.

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