Video quality-maximizing resource allocation and scheduling with statistical delay guarantees

Real-time video demands quality-of-service (QoS) guarantees such as delay bounds for end-user satisfaction. Due to the stochastic nature of wireless fading channels, deterministic delay bounds are prohibitively difficult to guarantee. Instead, this paper proposes providing statistical delay guarantees using the concept of effective capacity. A multiuser setup is considered whereby different users have (possibly different) delay QoS constraints. The resource allocation policy that maximizes the sum video quality is derived and has a useful intuitive interpretation: The optimal operating point per user is such that the rate-distortion slope is the inverse of the supported video source rate per unit bandwidth, termed source spectral efficiency. Scheduling policies are also proposed to select a maximal user subset such that all selected users can meet their statistical delay requirement. Results show that QoS-aware scheduling and resource allocation enable supporting significantly more users under the same resource constraints.