Performance Analysis of Proportional Fair Scheduling in OFDMA Wireless Systems

This paper analyzes the performance of Proportional Fair (PF) scheduling in Orthogonal Frequency Division Multiple Access (OFDMA) wireless systems. OFDMA represents a promising multiple access scheme for high-data-rate 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 simulation. We derive closed-form expressions for the average throughput and throughput fairness index. Computer simulations are used for verification. The analytical results agree well with the results from simulations, which verifies the correctness and accuracy of the analytical expressions.