在IEEE 802.16的網狀網路模式中，節點間的訊號處理以及資料的排程方式對系統的效能與容量有著極大的影響。本論文以OFDMA-TDMA做為實體層的資料子訊框，來增加節點在時槽配置上的彈性以期增加頻譜利用率。由於節點無法得知距離為二跳躍的節點之排程資訊，使得要求資料傳送的節點發生要求失效的問題，此問題將會導致傳輸效能降低以及存取時間的延遲。因此本論文針對該問題提出一獨特的時槽選擇機制，讓網路中的節點以不同的依據來做資料的排程，以降低要求失效的問題。在時槽選擇機制中，將本論文提出的”雜湊選擇機制（hash selection scheme；HSS）”來和一般選擇機制以及隨機選擇機制做比較，透過不同的拓樸分析在網狀網路中隱含的主要干擾狀況（primary interference scenario；PIS）和次要干擾狀況（secondary interference scenario；SIS）的問題，並對三種不同機制來比較其問題的改善。經過模擬程式的結果，本論文之方法在不同的拓樸中都有顯著的改善，且在輕載時最多能提高35%的產能，並且可使失效問題降低至0.05%。在重載時，HSS僅能提高約10%的效能，且失效問題也提高到27%，甚至到滿載時，HSS再也無法提升效能，失效問題也和另外兩種機制差不多。

In IEEE 802.16 mesh network, the transmission signaling and data scheduling method significantly affect the performance and capacity of the system. This paper propose a physical layer uses OFDMA-TDMA in the data subframe to improve data scheduling flexibility and spectrum efficiency. Because local nodes don’t know the exact scheduling information of 2-hop neighbors, the grant messages sent back by the receiver have the chance to collide with other’s decision, known as request invalid, and thus decreases throughput and increase access delay. Therefore, this paper provide an unique slot selection mechanism, known as hash selection scheme (HSS), to against the issue by allowing the node in the network to schedule data with a shifting basis. We compare three different slot selection mechanism, which include normal, random and HSS, on both primary interference scenario (PIS) and secondary interference scenario (SIS) with different topologies. Simulation results show that HSS is 35% better in throughput than others and reduces the request invalid ratio to 0.05% in the relative low loading system. In the relative heavy loading system, HSS is only 10% better in throughput than others and the request invalid ratio reach to 27%. In the full loading system, HSS improve the throughput anymore, and request invalid ratio is the same as others.

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