2. 802.11ac deployment common parameters
• Frequency band:
Compared with the 2.4G frequency band, the spectrum resources of the 5G frequency band are more
abundant. In the US region, there are currently 9 available 20MHz channels.
A wide range of spectrum resources can be used to achieve efficient channel multiplexing. For a typical Wi-
Fi network, it is recommended that adjacent APs use different channel ranges, that is, AP1 uses
CH36~CH48 frequency band, and neighbor AP2 uses CH149~CH165 frequency band. There is as much
channel isolation as possible between APs.
For some high-density scenarios, there are many clients, and the 2G itself spectrum may be extremely
crowded. However, many clients may still connect to 2G, which will result in a poor user experience. At this
time, it is recommended to enable band steering to 5G on dual-band SSID. Alternatively, you can even turn
off the 2.4G band SSID if possible.
• Channel and channel bandwidth selection:
Compared with the 2.4G frequency band, the spectrum resources of the 5G frequency band are more
abundant. In the US region, there are currently 9 available 20MHz channels.
A wide range of spectrum resources can be used to achieve efficient channel multiplexing. For a typical Wi-
Fi network, it is recommended that adjacent APs use different channel ranges, that is, AP1 uses
CH36~CH48 frequency band, and neighbor AP2 uses CH149~CH165 frequency band. There is as much
channel isolation as possible between APs.
For some high-density scenarios, there are many clients, and the 2G itself spectrum may be extremely
crowded. However, many clients may still connect to 2G, which will result in a poor user experience. At this
time, it is recommended to enable band steering to 5G on dual-band SSID. Alternatively, you can even turn
off the 2.4G band SSID if possible.
802.11ac provides a wider channel width up to 160MHz, and the conventional bandwidth is 20/40/80MHz.
However, the use of wider channels is very hard to realize in real-world environments.
• 2.4G channel bandwidth problem
Before talking about the 802.11ac channel and channel bandwidth selection, let's talk about the 2.4G
40MHz channel bandwidth. Figure 14 is the 2.4G channel distribution map. There are three non-overlapping
22MHz channels for planning and selection.