Scheduling alternatives for mobile WiMAX end-to-end simulations and analysis

Fourth Generation broadband wireless technologies such as WiMAX and LTE depend heavily in the performance of their schedulers to deliver high data throughput and meet quality-of-service commitments. This paper compares four different proposed schedulers for mobile WiMAX (Proportional Fairness (PF), Multiclass Modified Largest Weighted Delay First (MLWDF), Highest Urgency First (HUF), and Weighted Fair Queuing (WFQ) )in a range of environments. The evaluation is based on five industry-defined key performance indicators: average sector throughput, application throughput, average completion time, fairness index and delay). The schedulers are evaluated under three simulated environments: controlled (with a detailed analysis of each algorithm's behavior in terms of throughput over time), stationary and mobile. The controlled environment provides interesting insights about the behavior of flows with identical QoS parameters and different RF conditions, and helps to validate subsequent results obtained in the other two environments. Our results for the stationary and mobile environments show that all algorithms meet quality-of-service requirements within system capacity. Algorithms that maximize spectral efficiency (PF and MLWDF) also achieved considerable throughput improvements. MLWDF's throughput results, while outperforming all other schedulers under stationary conditions, fall behind PF in the mobile scenario. The variability introduced by the mobile environment yields no statistically significant difference among the schedulers. Copyrigh