Multiuser Multimedia Resource Allocation Over Multicarrier Wireless Networks

Abstract

We address the problem of multiuser video transmission over the uplink of multicarrier networks from an information theoretic perspective. Under the constraints imposed by the underlying physical (PHY) and medium access control (MAC) layers, we exploit the unique property of state-of-the-art video coders that can provide inherent bitstream prioritization in terms of distortion impact and solve the problem of allocating wireless resources, i.e., power/rate and subcarrier assignment, among multiple users such that the weighted sum of the overall video qualities is maximized. We focus on two different types of multiple-access strategies and their corresponding achievable rate regions, i.e., Shannon capacity region and frequency-division multiplexing access (FDMA) capacity region, in the Gaussian multiple-access channel. We propose two different approaches to optimize the multiuser multimedia transmission by considering the specific structures of both problems. First, for the general multiple-access strategy, under the constraint of its Shannon capacity region, we propose an algorithm to describe the achievable convex utility region directly. Second, for the FDMA strategy, we study the problem by relaxing the original integer programming problem into a convex optimization problem, which makes it tractable to find near-optimal solution analytically. For both multiple-access schemes, we start from the two-user case and develop algorithms for finding the (near) optimal resource allocation strategies. Inspired by the intuition gained from the two-user case, we extend the algorithms to the multiple-user case. Our numerical simulations show that the proposed resource allocation algorithms give significant performance improvements as compared to application-layer agnostic solutions that do not consider the quality impact.