An Improved Hybrid Scheduler for WiMAX and its Performance Evaluation

Anju Yadav, Prakash Vyavahare, Prashant Bansod
IEEE 802.16 based Worldwide interoperability for Microwave Access (WiMAX) provides broadband wireless access with integration of variety of applications such as voice, video and data with different Quality of Service (QoS) requirements. In WiMAX, MAC layer scheduling is an integral part of providing QoS to variety of services. In this paper, a hybrid WiMAX scheduler has been proposed and analytically modeled using Markov chain. The proposed scheduler consists of homogeneous scheduler, Weighted
more » ... cheduler, Weighted Fair Queuing (WFQ), strict priority and a Round Robin (RR) scheduler. Analytical modeling is carried out to investigate whether the proposed scheduler achieves the design goals namely low complexity, satisfying QoS requirements of a variety of applications, maintaining fairness among all applications. Markovian model balance equations are obtained and solved using matrix multiplication method to derive the performance metrics for comparison, such as throughput, mean queuing delay, and packet loss probability of each traffic and interclass fairness. The analytical results show that the proposed hybrid scheduler satisfies not only the QoS requirements of various applications but improves fairness among services.