在無線網路中，網狀模式(mesh mode)的網路具有低網路建置成本、結構擴充容易、非視距傳輸（non-line-of-sight；NLOS）、多重路徑傳輸、網路傳輸可靠度佳、系統容量及網路效能高等優點，可預期無線網狀網路將更能滿足下一代高速寬頻無線網路的需求。然而當行動裝置用戶的人數增多時，每台行動裝置用戶分配到的可使用頻寬（bandwidth）相對降低，傳輸品質與效能便會受到影響。
由於封包排程機制的優劣、傳送封包的路由方式及頻寬使用率等因素，都將影響無線網路的效率，對於改善服務品質(quality of service; QoS)與避免擁塞亦扮演著很重要的角色，因此在本論文中，我們將就網狀模式下之無線網路排程機制進行研究，提出以正交分頻多重接取(orthogonal frequency division multiple access; OFDMA)技術，設計一個二階段演算法作為頻寬管理機制，為每個節點設定一個權重（weight），稱為權重優先傳送順序演算法（weighted transmission order algorithm; WTO），以排列節點權重之傳送順序，來滿足各節點傳送封包的需求，並維持各節點的公平性。
最後，我們將所提出的方法與最常見的先進先出（first in first out; FIFO）競爭機制相比較。另外亦將WTO的頻寬配置方式改為OFDM配置並相互比較，從模擬結果顯示，在網狀網路環境下，本論文所提出的方法在網路負載增加時，系統容量及傳輸效能皆較其他兩種方式好，且仍保有各節點傳送資料之公平性。

In high speed wireless network, mesh model is deemed as a topology with characteristics of multi-path transmission, and thus benefits of high availability, high capacity and efficiency. However, the bandwidth allocated for each mobile device drops down as more devices attached to mesh network.
The scheduling mechanism, routing method and bandwidth utilization are all key factors for network efficiency, quality of service (QoS) improvement and congestion prevention. In this paper, we study the scheduling mechanism for mesh topology and propose a two-stage algorithm, named weighted transmission order (WTO) algorithm, for bandwidth management of OFDMA. WTO sets a weight for each node according to the topology and the transmission order is then determined respectively. In this way the equality of nodes is maintained.
We compared the weighted algorithm proposed with the most common first-in-first-out competition mechanism and WTO algorithm with bandwidth management of OFDM. The simulation result shows that in the mesh network environment, WTO retains the transmission throughput and balance of each node regardless of the network loading.

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