Quality of service scheduling based on utility prediction

Abstract

Next generation wireless systems are expected to provide broadband access service and efficient support to multimedia applications. To overcome tbe limitation due to harsh propagation environments and tbe scarce spectrum availability, advanced transmission tecbniques based on multicarrier schemes and adaptive modulation are commonly considered key elements. However, in order to fully exploit tbese transmission schemes, scheduling mecbanisms able to take advantage of tbe diverse channel conditions experienced by users and guarantee at the same time quality of service, are of paramount importance.In tbis paper we first propose a scheduling scheme tbat increases tbe achievable tbrougbput by combining multiuser diversity witb channel prediction. Tben we extend tbe proposed scheme to incorporate quality of service requirements of multimedia services.Tbe proposed solution bas been validated witbin tbe framework of tbe 1ST WINNER project by means of system level simulations.

Opportunistic scheduling policies for improved throughput guarantees in wireless networks

“…We can now fix the throughput guarantees B i of up to N -1 users and maximize the remaining throughput guarantees by solving the set of 3N equations resulting from (16), (10), and (12). To be able to solve this optimization problem, we can, for example, additionally constrain the users with non-fixed B i 's to have equal throughput guarantees.…”

“…To simplify the analysis, we shall fix the throughput guarantees B i /WT W of four users to the same value, and maximize the throughput guarantees for the remaining users by solving the set of 3N equations resulting from (16), (10), and (12). We further constrain the users with non-fixed B i 's to have equal throughput guarantees.…”

“…A utility-based predictive scheduler is proposed in [10] that focuses on fulfilling the throughput guarantees by predicting the future channel conditions and adopting the rates accordingly. At the current time slot, it schedules the user whose future channel conditions would make it more difficult to provide the throughput guarantees.…”

Maximizing the throughput guarantees in wireless networks under imperfect channel knowledge

“…Andrews et al [1] propose scheduling algorithms that try to fulfill the throughput guarantees by giving different priorities to the users depending on how far they are from their maximum and minimum throughput guarantees. A utility-based predictive scheduler is proposed in [2] that focuses on fulfilling the throughput guarantees by predicting the future channel conditions and adopting the rates accordingly. In [3], an algorithm aimed specifically at providing short-term throughput guarantees has been proposed.…”