Opportunistic bi-directional scheduling under quality of experience demands

Abstract

Quality of Experience (QoE) is a very important metric in wireless communication systems, where customers request strict QoE demands that translate into restrictions on both Uplink (UL) and Downlink (DL) connections. The development of wireless communications standards and the emergence of new interactive and conversational services with bi-directional QoE requirements changes the scheduling context from a link-level to a system level. To this end, this paper presents a joint UL-DL bandwidth allocation approach that considers outage as the main QoE parameter to be minimized. The well-known opportunistic scheduling algorithm is first modified to account for the UL-DL coupling and mathematical expressions of both the outage probability and its QoE are derived. Then the expressions are employed in the joint UL-DL bandwidth allocation problem. The formulated problem is shown to be a convex optimization problem. Simulation results demonstrate the merits of the proposed approach compared to traditional techniques.