A Scheduling Policy for Downlink OFDMA in IEEE 802.11ax with Throughput Constraints

TL;DR

This paper proposes a novel scheduling policy for downlink OFDMA in IEEE 802.11ax WiFi networks that ensures minimum throughput requirements are met, even in infeasible cases, outperforming existing strategies.

Contribution

It introduces a weighted max-min fairness scheduling policy specifically designed for downlink OFDMA with throughput constraints in 11ax, handling infeasible scenarios effectively.

Findings

Outperforms proportional fairness and sum-rate maximization strategies.

Ensures minimum throughput requirements are met.

Provides well-defined behavior in infeasible instances.

Abstract

In order to meet the ever-increasing demand for high throughput in WiFi networks, the IEEE 802.11ax (11ax) standard introduces orthogonal frequency division multiple access (OFDMA). In this letter, we address the station-resource unit scheduling problem in downlink OFDMA of 11ax subject to minimum throughput requirements. To deal with the infeasible instances of the constrained problem, we propose a novel scheduling policy based on weighted max-min fairness, which maximizes the minimum fraction between the achievable and minimum required throughputs. Thus, the proposed policy has a well-defined behavior even when the throughput constraints cannot be fulfilled. Numerical results showcase the merits of our approach over the popular proportional fairness and constrained sum-rate maximization strategies.