In this study, a playout buffer and discontinuous reception (DRX) aware scheduling scheme (PBDAS) is proposed to improve the video streaming transmission over the long term evolution systems by considering the characteristics of both the DRX mechanism and the HTTP streaming. First, to reconcile the three mechanisms, the metric called remaining playout time (RPT) is proposed, which can be used to estimate the playout status of the clients. With the RPT, the scheduler can accurately differentiate the urgency among the clients. Then, a two level resource allocation schemes is proposed. In the scheduler, the upper level is responsible for determining the scheduling set, while the lower level will be in charge of allocating the resource to the user equipments (UEs) in the set. With the scheduling set, the priority of the UEs can be accurately distinguished. For different scheduling set, different forms of metrics are designed, with which both the efficiency of the radio resource and the playout continuity can be significantly improved. In addition, a playout buffer level estimation method is given to improve the feasibility of the implementation of PBDAS. By analysing the behaviour of the playout buffer, the buffer level can be estimated with the cumulative serving rate and the HTTP streaming information, which can be obtained in the eNodeB and from the quality of experience reports, respectively. The simulation results show that PBDAS can shorten the total interruption duration of the existing schemes by about 50% as well as keep the power consumption at a low level.
['Yuchen Chen', 'Guizhong Liu']
Playout buffer and DRX aware scheduling scheme for video streaming over LTE system