於802.16網路中，不同頻道品質(channel quality)的連線，例如不同的調變技術(modulation)或封包遺失率，形成多速率(multi-rate)的網路環境。因此，頻寬分配演算法不只需考慮各種流量的服務品質(QoS)需求，也應將有限的頻寬分配給頻道品質較好的連線以最大化頻寬使用率。但據我們所知，目前尚未有相關研究解決這方面的議題。因此在本篇論文中，我們將提出一個頻道品質與QoS感知的頻寬分配演算法。此演算法除了能保證每個連線的QoS需求外，也能利用調整DL/UL頻寬比例來符合DL/UL的流量比例以及將頻寬分配給頻道品質較好的連線等方法來最大化頻寬使用率。模擬結果顯示此演算法除了能滿足每個連線的QoS需求，也能提供較高的頻寬使用率。

In IEEE 802.16 networks, channel experiencing various modulations and packet loss percentiles form a multi-rate environment. Thus, an excellent bandwidth allocation algorithm should not only satisfy various QoS requirements of heterogeneous traffic, but also dispense more bandwidth to the connection with better channel quality for maximizing bandwidth utilization. However, to the best of our knowledge, there is no any work dedicated to this. In this thesis, a channel quality and QoS aware bandwidth allocation algorithm is proposed. This algorithm can not only satisfy each connection's QoS requirement, but also maximize bandwidth utilization by dynamically adjusting the DL/UL bandwidth ratio to match the current DL/UL traffic ratio and allocating more bandwidth to the connections with better channel quality. Simulation results demonstrate that our algorithm can more satisfy each connection's QoS requirement and provide higher bandwidth utilization, comparing with the previous algorithms.

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