Summary: | 隨著IEEE 802.11無線傳輸頻率的快速發展,而傳輸距離卻隨著縮短,使得我們考慮多跳接的傳輸方式來擴展通訊的範圍。但是在IEEE 802.11 的多跳接無線網路中並沒有服務品質的保證,而且在傳輸上的效能不高,因此我們希望在IEEE 802.11 多跳接的無線網路中改善傳輸效能且提供服務品質保證。在這篇論文中,我們提出了一個安排MAC存取的方法,來達到服務品質保證。我們使用一個樹狀架構來建構這個無線網路並且運作訊標繞樹的動作來建立我們的分離集合,而分離集合提供我們安排無衝突傳輸。當訊務流在這個網路中產生,我們的方法能夠有效的安排MAC存取並且保證不同類型訊務之品質。我們同時也提供一種適應性安排機制,來有效利用整個網路的效能,並且避免重新安排整個網路的MAC存取規畫,來維持網路品質在適當的滿意度。實驗結果顯示我們在多跳接的無線網路中有效的達到服務品質保證。 === With fast development of radio frequency, the wireless communication in IEEE 802.11 is growing up to high transmission rate (802.11g). However the distance of transmission decreases when wave frequency increases. Thus there is growing need to extend communication distance through multihop transmissions. But there is no QoS in IEEE 802.11 Multihop Wireless Networks; it has poor performance on transmission. Thus we are motivated to provide QoS in IEEE 802.11 Multihop Wireless Networks. In This Thesis, we propose a MAC Access Scheduling Scheme to support guaranteed QoS in IEEE 802.11 Multihop Wireless Networks. We use a tree-based architecture to construct the network and form the operation of token traversal. Token traversal operation builds the Disjoint Set to support scheduling collision-free transmission. When traffic is generated to the network, our scheme provides efficient schedule of MAC access and guarantee the QoS of different types of traffic. We also provide a adaptive scheduling to utilize the network performance and avoid the overhead of re-schedule to maintain the network quality at a satisfied level. The simulation results show we achieve the network QoS efficiently and provide guaranteed QoS.
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