Date Added: Aug 2012
In this paper, the authors consider the problem of providing QoS (Quality of Service) guaranteed data download services in wireless networks with high energy-efficiency. To guarantee the QoS, a transmission deadline is set for each request, before which the whole data should be received by the user. To attain high energy-efficiency, multicast technique is adopted. Traditionally, the multicast rate is constant and independent of the number of users served in one session. However, they show that when they change the transmission rate dynamically according to current state, such as user numbers, more transmission energy can be saved.