A sleep-mode interleaving algorithm for layered-video multicast over mobile WiMAX

Mobile WiMAX is a promising technology to enable the wireless 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 significantly degrades the performance of the bandwidth-allocation mechanisms. We present a theoretical model for illustrating this interaction problem. To solve the problem, we propose a novel sleep-mode interleaving algorithm beyond the existing mechanisms. By appropriately adjusting one sleep-mode parameter, the proposed algorithm effectively guarantees the bandwidth efficiency of the video multicast mechanisms while the mobile stations can execute the standard sleep-mode operations. Simulation results demonstrate the effectiveness of our proposed algorithm in terms of the user satisfaction, power consumption and computational complexity.