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Journal of Electrical and Computer Engineering
Volume 2012 (2012), Article ID 680318, 12 pages
http://dx.doi.org/10.1155/2012/680318
Research Article

Analytical Evaluation of the Performance of Proportional Fair Scheduling in OFDMA-Based Wireless Systems

Faculty of Engineering and Applied Science, Memorial University, St. John’s, NL, Canada A1B 3X5

Received 2 March 2012; Accepted 7 May 2012

Academic Editor: Yi Su

Copyright © 2012 Mohamed H. Ahmed et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper provides an analytical evaluation of the performance of proportional fair (PF) scheduling in Orthogonal Frequency-Division Multiple Access (OFDMA) wireless systems. OFDMA represents a promising multiple access scheme for transmission over wireless channels, as it combines the orthogonal frequency division multiplexing (OFDM) modulation and subcarrier allocation. On the other hand, the PF scheduling is an efficient resource allocation scheme with good fairness characteristics. Consequently, OFDMA with PF scheduling represents an attractive solution to deliver high data rate services to multiple users simultaneously with a high degree of fairness. We investigate a two-dimensional (time slot and frequency subcarrier) PF scheduling algorithm for OFDMA systems and evaluate its performance analytically and by simulations. We derive approximate closed-form expressions for the average throughput, throughput fairness index, and packet delay. Computer simulations are used for verification. The analytical results agree well with the results from simulations, which show the good accuracy of the analytical expressions.