Lower signal since moving to OpenWrt

something is wrong. i picked 157. and it's connecting to 161.



You can't "arbitrarily" pick a "base" channel when it is a bandwidth that covers multiple channels. Various OSes will report a different channel for 40 MHz-wide channels.

See, for example http://www.revolutionwifi.net/revolutionwifi/2013/03/80211ac-channel-planning.html

I don't recall the channel numbers that hostapd permits for each bandwidth. Checking for the list in the source now.

Yeah, the 80Mhz channel width means that it uses "multiple channels" (specifically 4 channels at once) so some systems report that as a normal channel and then whether the additional channels are above vs below, other systems report the "average" of all the channels.

In my experience unless you have a totally quiet 5Ghz band, you're better off with 40Mhz channels than 80Mhz channels because interference is reduced.

So I should change the thing on the right to 40? And keep 157?


Also should I keep it 157 or move it to 161 since it’s forcing 161?

From http://blog.fraggod.net/2017/04/27/wifi-hostapd-configuration-for-80211ac-networks.html

Relation between these for 80MHz channels is the following one:

vht_oper_centr_freq_seg0_idx = channel + 6

Where "channel" can only be picked from the following list (see hw_features_common.c in hostapd sources):

36 44 52 60 100 108 116 124 132 140 149 157 184 192

And vht_oper_centr_freq_seg0_idx can only be one of:

42 58 106 122 138 155

Furthermore, picking anything but 36/42 and 149/155 is probably restricted by DFS and/or driver, and if you have any other 5G APs around, can also be restricted by conflicts with these, as detected/reported by hostapd on start.

This may be specific to US / North America, but even getting a functional 80 MHz channel can be challenging, especially if you're anywhere near "civilization" (meaning radar of any sort, including remote weather and navigational radar systems).

Edit: based on the linked chart, it looks like 149 can be a 20-, 40-, or 80-MHz channel, 157 could be only a 20- or 40-MHz channel, and 161 could only be a 20-MHz channel.

1 Like

Jeff. Can you translate that to English. I’m so lost.


149 seems to be the only "reasonable" choice for a hope at 80-MHz 802.11ac as:

  • All the "mid-band" channels in at least North America are subject to DFS
  • DFS typically pushes the channel downward, making 36 often highly congested.

149 is never a "guarantee", especially as many devices try 149 first and bandwidth will dynamically reduce if interference is seen.

So If i understand correctly I should use 149 at 80?

If you're going to try 80-MHz channels, 36 and 149 are the only reasonable "options", at least in North America. With 40-MHz channels, you have a couple more options, including 44 and 157.

Is 39 better than 149?

Which is going to give me the best speeds and coverage? 40 or 80?


It will all depend on what your neighbors are using. It's a "try it and see" kind of thing, and may vary by time of day (especially if they're watching reruns of The Sopranos or the like over wireless).

1 Like

I've picked 149. And 80. It looks like no one else is using it.


No change in having a crappy signal. Look at the wifi on the top right. That was always full power with the Linksys firmware.


Don't worry about the number of bars on the icon, what is the actual throughput and latency on the link? Run a speedtest here: http://www.dslreports.com/speedtest

1 Like


I stream my TiVo content to my iPad in the living room while others play video games on the main tv. I’m one room and a hallway from the router. It’s not working well tonight. Keeps losing signal. Chat support said there are no current issues.

I fear it’s more low signal strength.

Anyone’s thoughts?


Your device has both 5GHz and 2.4GHz, what channel are you actually connected to?

All of my devies connect to the 5 unless they are 'older' devices that will only connect to the 2.

So the TiVo and iPad use the 5. And of course our iphones with the 'lower' signal icon use the 5.


Would my screen caps of the signal noise be of any help? Or any other screen caps?


So now I see 3 of us on 149. Shouldnt I avoid that?