This visualization shows what type of channel bandwidth (also
is being used in the given WLAN area. Wi-Fi networks use three
types of channel bandwidth:
20 MHz Legacy: This is a legacy type used by 802.11 a/b/g
equipment. Each channel occupies 20 MHz of radio spectrum.
20 MHz HT and 40 MHz HT: These are bandwidth types introduced in
the 802.11n standard. They occupy either 20 MHz or 40 MHz of
spectrum space and use HT-mixed and HT-Greenfield frame formats.
20 MHz VHT, 40 MHz VHT, 80 MHz VHT, and 160 MHz VHT: These are new
types introduced in the 802.11ac standard. They use 20, 40, 80, or
160 MHz-wide channels. VHT is used only in the 5 GHz band.
Channel bandwidth is shown for the AP that has the strongest signal
in the given map area among the APs selected for analysis. This
mimics the roaming behavior of client adapters that connected to
the strongest AP. While other audible APs may offer other types of
bandwidth, a typical adapter will connect to the AP with the
strongest signal. You can deselect one or several of the selected
APs to see channel bandwidth types for less strong APs.
Double-clicking on the Channel Bandwidth legend on the status bar
allows you to configure the color scheme and change its value
If you see 20 MHz Legacy or 20 MHz HT channel bandwidth in the
areas where you expect to see 40 MHz HT, the following solutions
Check your AP configuration. If you are using newer 802.11n
equipment, make sure that it is configured to use 40 MHz or
automatic 20/40 MHz channel width.
Your AP's ability to use 40 MHz channels depends on the wireless
environment. A 40 MHz-enabled AP may fall back to 20 MHz mode in
some situations (e.g., when an 802.11n client that does not support
40 MHz bandwidth is connected). Because of the changing
environment, the site survey results regarding the channel
bandwidth may change from time to time. Perform site surveys
If you are using legacy 802.11 a/b/g equipment, consider upgrading
to 802.11n or 802.11ac.
If you see the HT channel bandwidth in the areas where you expect
to see VHT, make sure that your AP is configured to use the
802.11ac mode and that you have correctly configured its channel
width. Also, keep in mind that VHT is available only in the 5 GHz