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Re: Ver 1.7 Channel Width of 40MHz @ 5GHz for Wireless N

Posted: Mon Mar 30, 2015 9:02 pm
by ispyisail
Thanks guys

Eric doesn't always reply/comment but he will most likely read this thread and make some changes based on it.

Welcome to opensource :)

Re: Ver 1.7 Channel Width of 40MHz @ 5GHz for Wireless N

Posted: Mon Mar 30, 2015 9:54 pm
by griftopia
ispyisail wrote:Thanks guys

Eric doesn't always reply/comment but he will most likely read this thread and make some changes based on it.

Welcome to opensource :)
Thanks ispy. I'm guessing when trying to save 40Mhz setting from UI, the code must be doing some validation / conditional logic that is probably failing and it reverts to 20Mhz prior to persisting the changes. The fact that manually changing the channel width worked tells me, it is just a glitch.

However, for AP mode, I hope "Auto" gets added. I have never seen a firmware without this setting, although I don't know about OpenWRT since I never tried it (and after discovering gargoyle what's the point?) For those wanting to run both radios with SAME SSID, it is important to have "Auto" so AP can negotiate best throughput with wireless client device.

Re: Ver 1.7 Channel Width of 40MHz @ 5GHz for Wireless N

Posted: Mon Mar 30, 2015 10:22 pm
by lepgargoyle
griftopia wrote:
lepgargoyle wrote:Hi griftopia,

I remember having a similar issue with a wd my net n750 and openwrt bb firmware using luci web gui. Basically I had to force the 40mhz channel width for 5Ghz via command line. Also I've only ran the n750 in AP mode not client bridge; do you notice the same issue in AP mode? In any case you should be able to force 40mhz channel by editing /etc/config/wireless. For AP mode this my 5Ghz config (ispyisail latest 1.7.x release [3/26]):
***
config wifi-device 'radio1'
option type 'mac80211'
option channel '36'
option hwmode '11a'
option path 'pci0000:00/0000:00:00.0'
option htmode 'HT40+'
***
http://wiki.openwrt.org/doc/uci/wireless

HT20 (single 20MHz channel),
HT40- (2x 20MHz channels, primary/control channel is upper, secondary channel is below)
HT40+ (2x 20MHz channels, primary/control channel is lower, secondary channel is above).
Yes, same trouble in AP mode. I tried it just to see if set the channel, but no dice. I will try your suggestion to manually configure. I didn't want to earlier because I didn't want to mess things up, but I'll take backup of the config file and then try. God knows how the UI will render the setting after I do that though. Hope it does not crash rendering UI useless. But I guess if that happens I could always ssh into router and restore things back. Right?

Finally, a couple of clarifications. radio1 is the 5Ghz and radio0 is 2.5GHz? Maybe my 5Ghz is disabled ?!?!?! Finally what is hardware mode 11a? is that equivalent to N+A?

Thanks.

Great, you got it to work; most likely you can now use the GUI to make changes. Also 11a is just defining the 5Ghz band (which is the only band available for 'radio1'). Mode/spec 802.11a or 802.11n is defined with htmode: https://dev.openwrt.org/ticket/17541

And you correct about CH 36 being the bottom of the band and only selecting upper channel 'HT40+' or CH 161 being the top band and only selecting lower 'HT40-'. However gargoyle's web gui is nice in that it will display only the appropriate channels (primary/control) depending on which bandwidth option is selected:
'HT40+' = CH 36, 44, 149, 157 or 'HT40-' = CH 40, 48, 153, 161

Re: Ver 1.7 Channel Width of 40MHz @ 5GHz for Wireless N

Posted: Sat Apr 18, 2015 10:09 pm
by Eric
Sorry it took me so long to look into this... but I'm trying to reproduce the bug and having problems -- setting the 40MHz channel width seems to work fine for me.

Make sure that if you have selected the AP to run on a channel in the high range of the band, you select 40MHz (2nd channel below), while if your AP channel is in the low range of the band select 40MHz (2nd channel above).

Is anyone besides griftopia experiencing/able to reproduce this issue? It wasn't clear to me glancing at the discussion above.

Re: Ver 1.7 Channel Width of 40MHz @ 5GHz for Wireless N

Posted: Wed Oct 31, 2018 8:54 am
by agrohe21
Does this mean that for 2.4 radio, we have to choose a specific channel? I am getting some interference on channels and would like the device to "auto" choose the best without interference. Is this possible? I am on v1.10.

Re: Ver 1.7 Channel Width of 40MHz @ 5GHz for Wireless N

Posted: Wed Oct 31, 2018 4:17 pm
by Lantis
There is no automatic channel selection in Openwrt.
Even though Openwrt offers an “auto” setting (which Gargoyle does not), it simply chooses the first channel in the list (i.e. 1 or 36).

You might like to use the spectrum analyser plugin to do your own investigation before deciding on a final channel.

Re: Ver 1.7 Channel Width of 40MHz @ 5GHz for Wireless N

Posted: Thu Feb 20, 2020 10:04 pm
by agrohe21
For this reason, I ended up using Gargoyle for only non-wifi stuff and got an Orbi mesh setup for all my wifi needs. Super happy with the division of labor.