Performance enhancement using opportunistic schedulers in wireless networks

Maximizing system performance under various Quality of Service (QoS) constraints to cope with the rapidly growing demand of wireless applications is emerging as one of the important goals of future wireless networks. An obvious way to improve the performance is by incorporating appropriate scheduling mechanism in such networks. Although, scheduling has been extensively studied in different disciplines like operations research and wire-line networking, the unique characteristics of wireless networks, namely the time varying channel conditions and multi-user diversity necessitate the development of new scheduling solutions. Consequently, designing scheduling mechanisms that take advantage of time-varying channel conditions, is necessary to improve system performance. However, this has to be done in such a way as to ensure some level of fairness among the users. One such scheduling mechanism termed opportunistic scheduling is investigated in this paper. An attempt is made to maximize system throughput while satisfying the QoS metric, user temporal fairness. A performance comparison is made with the existing non—opportunistic scheduling schemes and the results are presented.