AN EFFICIENT SCHEDULING ALGORITHM FOR REAL-TIME BROADCAST IN WIRELESS LAN

摘要

In this paper, we focus on scheduling algorithm for realtime on-demand data broadcast in wireless local area networks (WLANs). We propose a simple, but nevertheless very efficient algorithm, called RWw with channel state estimator (RWw-CSE), for designing the broadcast schedule that considers what to broadcast and when to broadcast Our algorithm operates at link layer level, and is coupled closely with distributed coordinate function (DCF). In RWw-CSE, R is the number of outstanding requests for an item, W is the maximum waiting time of these requests, and w is the value of weight of the item. The weight of real-time items is larger than that of non-real-time items. When the channel is in good state, the server chooses to broadcast the item with the largest value of R~* W~* w. Our algorithm considers not only the wireless channel state, but also the environment where real-time information and non-real-time information coexist Through extensive simulations, the results show that our scheduling algorithm can reduce the access time to schedule the real-time information, and the average access time to schedule the non-real-time information.