對新一代的無線網絡（例如WiMAX）而言，正交分頻多工（OFDMA）的技術可以提供高速的資訊傳輸，因此成為一個很有吸引力的訊號調變方式。在一個 OFDMA時幀（OFDMA frame）中，突簇（Burst）是用來傳輸基地台（Base Station）與用戶站（Subscriber Station）之間訊息的一些無線資源。由於無線資源稀少，如何有效地分配這些資源給用戶站成為一個重要問題。在本文中，因為用戶花費大多數的時間從基地台下載資訊，所以我們特別注重下行突簇分配的問題。在合作式的OFDMA網路環境中，我們提出了一個資源分配和調度的方法來解決這些突簇分配的問題，同時將使用者所需求的服務品質以及使用最多一個中繼站（Relay Station）協助訊息傳輸的情形也列入考慮。實驗結果證明，我們提出的方法可以最大限度地減少傳輸時間，從而增加網絡的吞吐量。

Orthogonal Frequency Division Multiple Access (OFDMA) is an attractive modulation technique adopted in new generation wireless networks, such as WiMAX, to provide high-speed transmission. In an OFDMA frame, burst is the radio resource allocated by Base Stations (BSs) for Subscriber Stations (SSs) to receive or transmit data. Due to scarcity of radio resource, how to allocate bursts to SSs efficiently becomes an important issue. In this paper, we especially focus on the downlink burst allocation problem because users spend most of their time to download data from BSs. A QoS-based resource allocation and scheduling scheme is proposed aiming to deal with the burst allocation problem in cooperative OFDMA wireless networks. Consideration of QoS guarantee and two-hop transmission can also improve the efficiency of the proposed scheme. Simulation results show that our proposed scheme can minimize the transmission time and thus increase thenetwork throughput.

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