The 802.11ac wireless LAN standard provided additional channel bonding capabilities for 80 MHz/160 MHz and a split mode 80+80 MHz. The channel bonding capabilities build upon the channel bonding capabilities of 802.11n.
The HT capability/Operation elements provided the primary channel information and the secondary channel information in the case of 40 MHz channel bonding as is described in the previous section for 802.11n.
For 80MHz/160MHz and 80+80MHz operation – supported channel width and channel centre frequency were defined in the 802.11ac standard VHT Capabilities and Operation elements. The primary channel was still the channel as described in the HT capabilities element.
The VHT Capabilities element is provided below
FIG COURTESY: 802.11acTM Standard
The VHT Channel bonding settings can be best understood via the tabular column provided below
FIG COURTESY: 802.11acTM Standard
The VHT Operation element provided the centre frequency details for 80MHz/160MHz and 80+80MHz Operation. The VHT Operation Element is provided below
FIG COURTESY: 802.11acTM Standard
The channel centre frequency segment 0 defines the channel centre frequency for an 80 MHz and 160 MHz channel bonding operation. The Channel centre frequency segment 1 defines the channel centre frequency for the upper 80 MHz in a split 80+80 MHz channel bonding operation.
The below Wireless capture example indicates the VHT Operation Element setting for 80 MHz operation
The below tabular column from the 802.11ac standard explains the operation of the VHT operation element
FIG COURTESY: 802.11acTM Standard