Studies on the Short Term Fairness Properties of Joint Scheduler

Abstract

Since the utilization of multiuser diversity in wireless networks can increase the information theoretic capacity, much attention has been paid to packet schedulers exploiting multiuser diversity. However, it is known if there exists a tradeoff between the information theoretic capacity and fairness achieved by schedulers exploiting multiuser diversity. Therefore, the authors consider the fairness of the schedulers exploiting multiuser diversity as well as their information theoretic capacity. Among schedulers exploiting multiuser diversity, the one-bit feedback fair scheduler is considered an attractive choice due to its good balance between the capacity and fairness. This paper considers a joint scheduler which incorporates the weighted round-robin scheduling into the one-bit feedback fair scheduling. It is expected that by incorporating the round-robin scheduling into the one-bit feedback fair scheduling, the short term fairness of the scheduler is greatly improved. Considering the statistical time-access fairness index (STAFI) as a measure of short term fairness, the authors study the short term fairness properties provided by the joint scheduler. The effects of the threshold of the scheduler on the STAFI are investigated. The threshold of the scheduler strongly affects its short term fairness properties.