Maximum bandwidth can be adjusted for each WLAN module

Changes to WLCs

Max. channel bandwidth

Enter how and to what extent the AP specifies the channel bandwidth for the physical WLAN interface(s). The following values are possible:

• Automatic: The access point automatically detects the maximum channel bandwidth (default).
• 20MHz: The access point uses channels bundled at 20 MHz.
• 40MHz: The access point uses channels bundled at 40MHz.
• 80MHz: The access point uses channels bundled at 80MHz.

By default, the physical WLAN interface automatically determines the frequency range used to modulate the data onto the carrier signals. 802.11a/b/g use 48 carrier signals in one 20-MHz channel. The use of double the frequency range of 40 MHz means that 96 carrier signals can be used, resulting in a doubling of the data throughput.

802.11n can use 52 carrier signals in a 20-MHz channel for modulation, and even up to 108 carrier signals in a 40-MHz channel. The use of the 40 MHz option for 802.11n therefore means a performance gain of more than double.

Changes to stand-alone APs