Bit-rate Allocation, Scheduling, and Statistical Multiplexing for Wireless Video Streaming

Due to the scarcity of wireless resources, efficient resource allocation is essential to the success of cellular systems. With the proliferation of bandwidth-hungry multimedia applications with diverse traffic characteristics and quality of service requirements, the resource management is becoming particularly challenging. In this thesis, we address some of the key link-layer resource allocation mechanisms that affect the performance of video streaming in cellular systems: bit-rate allocation, opportunistic scheduling, and statistical multiplexing. The bit-rate allocation problem involves the distortion-optimal assignment of source, channel, and pilot data rates under link capacity constraints. We derive an analytical model that captures the video distortion as a function of these data rates and, based on it, we study various bit-rate allocation strategies. The opportunistic scheduling problem addresses the throughput-optimal assignment of time-slots among users with diverse channel conditions under certain fairness constraints. We focus on two aspects of the opportunistic scheduling: the performance of delay-constrained streaming applications and possible extensions of the opportunistic concepts to multicast scenarios. Finally, the statistical multiplexing is a resource-efficient method for smoothing out the extreme burstiness of video streams. We study possible statistical multiplexing gains of H.264 video streams in the context of E-MBMS architecture.