Performance Analysis of Opportunistic Channel Bonding in Multi-Channel WLANs

In this paper, an analytical framework is developed to study the performance of opportunistic channel bonding in IEEE 802.11 WLANs. Specifically, we consider a WLAN operating on multiple channels shared by both legacy users and IEEE 802.11ac users with channel bonding capability. By capturing the opportunistic channel bonding from the IEEE 802.11ac users in the primary channel and the random access of legacy users in the secondary channels, we derive the successful channel bonding probability, and the throughput of both legacy and IEEE 802.11ac users. Our analysis shows that with multi-channel bonding, ac users achieves a higher throughput at the cost of reduced throughput of legacy users in the secondary channels. The channel bonding achieves a higher total network throughput only when there is no legacy user in the secondary channels, and the total throughput decreases when legacy users exist due to the increased contentions in the secondary channels. The analysis provides important guidance for the deployment of multi-channel WLANs where ac users should select a proper primary channel to maximize its bonding opportunity and to attain the maximum throughput. Extensive simulations are conducted to validate the analysis.