在無線WiMAX中繼站網路，網路中需求相同資料影片串流的使用者，在過去方法只考量基地台收集的使用者頻道品質，及基地台頻寬限制下，最大能提供傳輸的資料，群播給網路中的使用者，以此減少傳送資料給使用者的廣播次數，降低傳送所需的資源。然而因為現今H.264/SVC影片技術的提升，一個影片可分割為不同層級影片品質的串流，所以當使用者需求不同層級影片品質時，傳遞給使用者的影片串流大小也是不同的，因此，過去資源分配方法因為沒有考量到使用者需求的差異，在此情況下是很難去分配頻寬的。本論文中，提出下述的三個分配資源的問題來解決，第一，在頻寬沒限制時，如何用最少頻寬傳遞給網路中所有使用者，第二，在有限定的頻寬下，如何將影片資料群播給使用者能獲得最大的網路流量，最後，在有限定的頻寬下，如何群播傳遞給網路中使用者能滿足最多人的需求。而以上三個問題的解答，可以提供策略給提供影片服務的電信公司來因應不同的網路情況。我們證明了第一個問題我們可以找到最佳化的解，而第二個問題及第三個問題為NP-hard問題，我們同時提出了時間複雜度在多項式時間內的啟發式GWA演算法來解它們。最後模擬結果顯示，在以上三種考量底下能在頻寬消耗，網路流量，使用者數量，能達到接近最佳解的效能。

關鍵字：群播 , 無線WiMAX中繼站網路 ,H.264/SVC

IEEE 802.16j (WiMAX relay networks) uses relay stations to extend the coverage of the base station and increase the network throughput. In this thesis, we propose three resource allocation schemes for multicast multi-layer video services in IEEE 802.16j networks. First, we propose an optimal resource allocation scheme that can serve all users with the minimum bandwidth consumption. Then, we consider the problem to maximize the network throughput with limited bandwidth and the problem to maximize the number of satisfied users with limited bandwidth. Since both problems are NP-hard, we propose two heuristic algorithms to solve them in polynomial time complexity, respectively. The simulation results show that the performance of our algorithms is close to optimal answer. Our algorithms can achieve minimum resource consumption, good network throughput, and more number of satisfied users.
Keywords: Bandwidth allocation, H.264/SVC, IEEE 802.16j, multicast, WiMAX

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