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Can't Set 1552 to use 802.11a 40 MHz channels

I am testing a Cisco 1552 and cannot seem to set it to use the 40 MHz channels. In the controller GUI is is set to use 40 MHz channels under DCA for 802.11a but when I go into the CLI and show the config of the AP it shows the channel width to be 20 MHz. If I try to change the channel width through the CLI I get "radio is not disable or ap not set to customize" or something like that. The radio is disabled globally and locally. Is there a way to set the AP or radio to a "customize" mode?

What prompted this was I was testing the throughput on it and can only get a 130 mbps data rate connection to it. The data sheet says it will support 300 mbps with the 40 mhz channel so I was trying to test it atteh higher rate.

The HW is a Cisco 4402 with 7.0.230 software on it, 1552E.

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Can't Set 1552 to use 802.11a 40 MHz channels

In order to set the 40mhz channel width, you will need to disable the 802.11a radio and enable that setting.  Disabling the radio is the only way to make that change.

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Can't Set 1552 to use 802.11a 40 MHz channels

Let me be more clear. I disabled the 802.11a radios prior to making the change. In the WLC GUI it shows it set to 40 MHz. When I do a "show ap 1552 config" it shows the channel width at 20 MHz. With 802.11a radio disabled all attempts to set the 1552 to 40 MHz fail.

Community Member

Can't Set 1552 to use 802.11a 40 MHz channels

I found that I can only set the 1552 to use a 40 MHz channel width using custom channel settings per AP versus doing it globally under DCA. When the DCA is set to 40 MHz it doesn't apply to the 1552s. I had to set the AP to "customize" for channel on the 802.11a radio config page for the AP and then I could set it to use 40 MHz. Worked fine and I got the higher data rates and great throughput. The only problem I have with that is when you set it to customize then you have to set you channel frequency manually. Not a huge problem but you wouldn't be able to use the automatic channel assignments provided by the WLC.

Does this sound right? Am I doing something wrong or not understanding how to configure 20 and 40 MHz channel width for 802.11n?

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