Issues with defining and using channels

RouterOS Wireless Networking
1

Intel ATOM board with a R11e-5HacD card running 6.29.1 L4…

If edit the wlan interface and configure 5GHz-A/N, 20/40MHz - Ce, and 5180, it’s accepted just fine. If I create a channel named 38Ce with the exact same settings and select it in the Frequency dropdown of the interface, I get “unsupported channel” when I try to apply. This happens on any 40MHz channel definition.

For 80MHz channels, I can manually set the interface just fin, but I can’t even define a channel because I get a “non-standard channel width” error. What’s non-standard about an 80MHz AC channel?

Any help would be appreciated. I’m going to have to deploy about 300 radios over the next 2 months so I want to get the kinks ironed out in the lab rather than on a rooftop in Texas in July.

2

I think you are trying to make Advanced channels which by default is not available.

More information : http://wiki.mikrotik.com/wiki/Manual:Wireless_Advanced_Channels

If I didn’t get you right, please post [ /interface wireless print advanced ] output of your current settings and then CLI command for what you trying to change. e.g. [ /in wireless set wlan1 channel-width=20/40mhz-Ce ]

In case Advanced channels is what you want, you need to write to MikroTik Support and ask for Advanced Channels support. It’s standard procedure.

3

That’s just it… There’s nothing advanced about a channel with a center frequency of 5180, a bandwidth of 40MHz and an extension channel of Ce. That a standard ‘N’ channel.

I can set that in the interface just fine:

Flags: X - disabled, R - running 
 0    name="wlan2" mtu=1500 mac-address=4C:5E:0C:12:80:ED arp=enabled interface-type=Atheros AR9888 
      mode=ap-bridge ssid="mt3" frequency=5180 band=5ghz-onlyn channel-width=20/40mhz-Ce scan-list=default 
      wireless-protocol=any vlan-mode=no-tag vlan-id=1 wds-mode=disabled wds-default-bridge=none 
      wds-ignore-ssid=no bridge-mode=enabled default-authentication=yes default-forwarding=yes 
      default-ap-tx-limit=0 default-client-tx-limit=0 hide-ssid=no security-profile=default compression=no

However with a channel defined:

list=N name="38Ce" frequency=5180 width=40 band=5ghz-onlyn extension-channel=Ce

I get:

[admin@mt3] /interface wireless> set frequency=38Ce 0
[admin@mt3] /interface wireless> print
Flags: X - disabled, R - running 
 0    ;;; unsupported channel: 38Ce
      name="wlan2" mtu=1500 mac-address=4C:5E:0C:12:80:ED arp=enabled interface-type=Atheros AR9888 
      mode=ap-bridge ssid="mt3" frequency=38Ce band=5ghz-onlyn channel-width=20/40mhz-Ce scan-list=default 
      wireless-protocol=any vlan-mode=no-tag vlan-id=1 wds-mode=disabled wds-default-bridge=none 
      wds-ignore-ssid=no bridge-mode=enabled default-authentication=yes default-forwarding=yes 
      default-ap-tx-limit=0 default-client-tx-limit=0 hide-ssid=no security-profile=default compression=no 
[admin@mt3] /interface wireless>
4

It’s because your are trying to use 40 Mhz channel width with extension channel Ce and of-course it’s not standard.

If you want 20/40Mhz Ce Channel Width entry should look like:

/interface wireless channels
add band=5ghz-onlyn extension-channel=Ce frequency=5180 list=N name=38Ce width=20

5

I’m sorry, I must be missing something.

Ce is by definition a 40MHz channel with the Control channel being in the lower 20MHz and the extension channel in the upper 20MHz. Are you saying we shouldn’t use the Width field in channels? Or does Width mean the width of the Control channel?

6

No I’am not saying that you shouldn’t use width field of channels, you can set there 5/10 Mhz etc. channel widths. Yes you can think of this field as Center channel width, however it will match with Extension channel width.

7

Ok, I understand now. Thanks!