A QoE-Fair Synchronized Transmission Scheme for Edge-Assisted Interactive Virtual Reality

In multi-user interactive virtual reality scenarios, synchronization among users is crucial for interactions smoothness. In this paper, we focus on the comprehensive synchronization requirements, not only the immersive timing experience, but also the QoE fairness among multiple sessions. A QoE-fair optimization problem is formulated, aiming at maximizing QoE fairness while providing immersive experience with high frame transmission rate, low end-to-end delay, and synchronization among users. The proposed approach requires edge-cloud collaboration, consisting of a compression control algorithm in edge servers and a synchronization decision algorithm in cloud servers. The former algorithm restricts the range of compression ratio according to the network condition and considers cumulative delay to satisfy the low end-to-end delay requirement, maximizing the QoE in each session. The latter algorithm selects the optimal aggregation decision to maximize QoE fairness among synchronized users. Simulation results demonstrate that the proposed scheme outperforms other solutions and variants in terms of QoE performance as well as QoE fairness.