In the next-generation wireless networks, mobile WiMAX is a promising technology to enable the real-time video multicast services, such as mobile IPTV and live athletic events. For supporting such bandwidth-eager and energy-hungry applications, the efficient bandwidth-allocation and energy-saving mechanisms should be simultaneously employed. In this paper, we first investigate how the WiMAX energy-saving mechanism influence the bandwidth-allocation efficiency of a WiMAX system. This paper presents a theoretical model for illustrating the interaction problem. To solve this problem, we propose a novel sleep-mode interleaving algorithm. By appropriately adjusting the sleep-mode parameters, the proposed algorithm effectively guarantee the performance of the bandwidth-allocation mechanism while the mobile stations can normally execute their sleep-mode operations. Simulation results demonstrate the effectiveness of our proposed algorithm in terms of the user satisfaction, power consumption and computational complexity.

移動全球互通微波存取(Mobile WiMAX)網路技術可應用於無線影片群播服務，例如IPTV網路電視及即時賽事轉播。為了支援這類重視頻寬及電力需求的應用服務，高效率頻寬資源分配與省電機制必須同時使用。本文中，我們首先研究WiMAX的省電機制為何會影響並降低頻寬分配上的效能，在此我們設計一個理論數學模型說明此交互影響的問題。為了解決這個問題，我們提出了針對此機制的一個創新的省電模式睡眠交錯演算法。藉由適當的調整省電模式的參數，此演算法可在移動設備執行省電模式時，同時有效的保持影片群播的頻寬效能。模擬結果顯示我們提出的演算法在使用者滿意度、能源耗費，以及執行時間複雜度上皆有較好的數值。

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