Multiple Dumb AP's | Wireless channel setup for best performance?

Installing and Using OpenWrt
1

I have five CAT6 runs in my home to specific locations. I have three of these units that I have openwrt installed all as DumbAPs in 3 different rooms:

What is the best method for 5Ghz freq setup?

A.) Least conflicting freq with other devices in my neighborhood. I live in a Lombardo home community, so at least a dozen homes in close proximity.

B.) Will get the best wireless speeds possible.

#Common neighborhood 5Ghz freq
36, 44,149, 153, 157, 161, 165

Current 5Ghz freq:

DUMBAP_1 = Chan 40
DUMBAP_2 = Chan 161
DUMBAP_3 = Chan 153

root@DUMBAP_1:/etc/config# iwinfo phy1-ap0 freqlist
    5.180 GHz (Band: 5 GHz, Channel 36) [NO_HT40-]
   * 5.200 GHz (Band: 5 GHz, Channel 40) 
    5.220 GHz (Band: 5 GHz, Channel 44) 
    5.240 GHz (Band: 5 GHz, Channel 48) 
    5.260 GHz (Band: 5 GHz, Channel 52) 
    5.280 GHz (Band: 5 GHz, Channel 56) 
    5.300 GHz (Band: 5 GHz, Channel 60) 
    5.320 GHz (Band: 5 GHz, Channel 64) [NO_HT40+]
    5.500 GHz (Band: 5 GHz, Channel 100) [NO_HT40-]
    5.520 GHz (Band: 5 GHz, Channel 104) 
    5.540 GHz (Band: 5 GHz, Channel 108) 
    5.560 GHz (Band: 5 GHz, Channel 112) 
    5.580 GHz (Band: 5 GHz, Channel 116) 
    5.600 GHz (Band: 5 GHz, Channel 120) 
    5.620 GHz (Band: 5 GHz, Channel 124) 
    5.640 GHz (Band: 5 GHz, Channel 128) 
    5.660 GHz (Band: 5 GHz, Channel 132) 
    5.680 GHz (Band: 5 GHz, Channel 136) 
    5.700 GHz (Band: 5 GHz, Channel 140) 
    5.720 GHz (Band: 5 GHz, Channel 144) [NO_HT40+]
    5.745 GHz (Band: 5 GHz, Channel 149) [NO_HT40-, NO_160MHZ, NO_IR]
    5.765 GHz (Band: 5 GHz, Channel 153) [NO_160MHZ, NO_IR]
    5.785 GHz (Band: 5 GHz, Channel 157) [NO_160MHZ, NO_IR]
    5.805 GHz (Band: 5 GHz, Channel 161) [NO_160MHZ, NO_IR]
    5.825 GHz (Band: 5 GHz, Channel 165) [NO_HT40+, NO_160MHZ, NO_IR]

wireless config:

config wifi-device 'radio0'
	option type 'mac80211'
	option path '1e140000.pcie/pci0000:00/0000:00:00.0/0000:01:00.0'
	option channel '1'
	option band '2g'
	option htmode 'HT20'

config wifi-iface 'default_radio0'
        option device 'radio0'
        option network 'lan'
        option mode 'ap'
        option ssid 'sr_guy-2Ghz-Den'
        option key 'password'
        option encryption 'psk2'

config wifi-device 'radio1'
	option type 'mac80211'
	option path '1e140000.pcie/pci0000:00/0000:00:01.0/0000:02:00.0'
	option channel '40'
	option band '5g'
	option htmode 'VHT80'

config wifi-iface 'default_radio1'
        option device 'radio1'
        option network 'lan'
        option mode 'ap'
        option ssid 'sr_guy-5Ghz-Den'
        option key 'password'
        option encryption 'psk2+ccmp'
2

The rule of thumb states that you should use separate channels, if you have many devices and want to maximize performance, or the same channel, if you want your devices to change quickly from one station to another, when moving around.

1 Like
3

Lombardo home community in Italy, or Lombardo Homes in U.S. (Michigan or Missouri?)? Reason I'm confused is you say your neighbors are using 165, but in Europe that would be a restricted short range device channel and your iwinfo listing indicates some restrictions on even 40 MHz wide channels. Have you set the correct country code in your wireless configuration?

In any event, the process is the same.....take a look at a WiFi analyzer survey (phone app, PC app, etc.) to see what is around you on 5 GHz. A weak neighbor WiFi signal (more than ~20 dBm lower in power than your WiFi signal) on the same channel should cause minimal interference, so I wouldn't go to any trouble to avoid those.

Using 120-128 is asking for more DFS weather radar conflicts, so I'd avoid those.

80 MHz wide channels will probably give you the best throughput.

Within those constraints, I would put your three AP's on different channels so they don't interfere with each other. If that cannot be avoided, have the two AP's furthest from each other share a channel range.

If you are in the U.S., I would start with 149-161 for one AP, and 52-64, 100-112 or 132-144 for the second and third. The obvious range of 36-48 I have left off for two reasons: a) everyone else in the neighborhood probably uses it, b) despite the FCC allowing up to 30 dBm on 36-48 in the U.S. (just like 149-165) and the FCC certifying devices for greater than 23 dBm in this range, I've noticed the regdb recently used by OpenWrt started restricting power to 23 dBm in UNII-1 (channels 36-48) on such devices anyway, whereas up to the FCC limit of 24 dBm is still allowed from channels 52-144. It's just 1 dBm, but you might as well use a channel range that lets you make use of it.

Above is focused on performance (different channels), but something you could look into for roaming even using different channels is 802.11r fast transfer. All the SSID's, passwords and security should be the same for all SSID's assigned to the same interface (LAN or VLAN) on all your AP's to do this.