Hysteresis based rate adaptation for scalable video traffic over an LTE downlink

This work focuses on scheduling multiple video flows on the downlink of a wireless system based on Orthogonal Frequency Division Multiple Access (OFDMA), such as the LTE/LTE-A standard. We propose a joint multi-user scheduling and multi-user rate adaptation strategy by considering Scalable Video Coding (SVC) which facilitates the truncation of bit streams, thus allowing graceful degradation of video quality in the event of wireless channel variations or network congestion. The proposed scheduler utilizes Quality of Experience (QoE)-aware priority marking, where video layers are mapped to priority classes, and targets at minimizing delay bound violations for the most important priority classes under congestion. In order to reduce congestion, we propose multi-user rate adaptation at the MAC layer via a novel dynamic filtering policy for QoE based priority classes. Simulation results show that the proposed approach delivers to the end users a better QoE, with lower complexity, than state-of-the-art cross-layer approaches.