Throughput Optimal Switching in Multi-channel WLANs

TL;DR

This paper investigates how incorporating both signal quality and congestion into channel switching decisions can optimize throughput in multi-channel WLANs, proposing a scheme that maximizes system performance.

Contribution

It derives the stability region for multi-user multi-channel WLANs and identifies the throughput optimal switching scheme within a specific class.

Findings

Derived the stability region of the system.

Identified the throughput optimal switching scheme.

Abstract

We observe that in a multi-channel wireless system, an opportunistic channel/spectrum access scheme that solely focuses on channel quality sensing measured by received SNR may induce users to use channels that, while providing better signals, are more congested. Ultimately the notion of channel quality should include both the signal quality and the level of congestion, and a good multi-channel access scheme should take both into account in deciding which channel to use and when. Motivated by this, we focus on the congestion aspect and examine what type of dynamic channel switching schemes may result in the best system throughput performance. Specifically we derive the stability region of a multi-user multi-channel WLAN system and determine the throughput optimal channel switching scheme within a certain class of schemes.