IEEE 802.11ac: Dynamic Bandwidth Channel Access

IEEE 802.11ac is enhancing the throughput beyond IEEE 802.11n using the 80 MHz channel bonding technique. In this paper, we first overview the static 40 MHz and the dynamic 20/40 MHz bandwidth channel access schemes defined in 802.11n. We then extend the schemes to the IEEE 802.11ac for the 80 MHz wide channel and study the static and dynamic channel access schemes. The simulation results show that dynamically switching between 20, 40, and 80 MHz bandwidths based on the clear channel assessment (CCA) result of each 20 MHz channel outperforms the static 80 MHz scheme by 85 % in terms throughput when the secondary channels are occupied by the 802.11a stations with moderate traffic loads. The paper also investigates the effects of the secondary channel CCA sensitivity and the primary channel selection on the 802.11ac throughput.