Hello,
is it possible to reduce the bandwidth in the 5 GHz band to 5 or 10 Mhz?
I see only the options 20 Mhz or 40 MHz in the web interface, but I know
that some routers also provide the option for lower bandwidths.
Lower bandwidth -> less interference -> more channels -> longer range
(if you don't need a very high speed).
Any comments welcome!
Uwe
Sub-20MHz channels are only configurable via debugfs and are not supported by LuCI or any of the standard Linux wireless utilities. Try echo 5 > /sys/kernel/debug/ieee80211/phy0/ath9k/chanbw on both sides of a working p-t-p link.
How to execute this comand..?
I remember there were patches for this on the ath9k driver at least. You could add "option chanbw 10" (or 5) to /etc/config/wireless
I didnt check, but are those patches still part of the mac80211 kernel module??
This actually improves your connections, bandwidth, speed, etc? is 5Ghz so used on all channels where you live ? Did you have problems with devices when you changed to 5/10Mhz band ? Which channel do you use?
It is really interesting to me this, where I live there almost no 5Ghz signals around. I am in typical very populated area city.
Moving to the 5Ghz band would be my suggestion too in a crowded 2.4Ghz area. A simple Dual band AC Lede compatible router could be found for under 20 USD.
Using half (10Mhz) or quarter channel bandwidth will give slower speeds, but might still work better due to less interference.
I could not find the references, but I think the 5 and 10Mhz bandwidth was dropped from the official ieee80211 specs.
I think that would be a good option, it is used by the ham radio guys for their hamnet 
Should still work on Atheros chips.
I was using 5ghz, since about a year with no problems... I have a LOT of SSID's around with a lot of signal and almost no one have 5ghz. some ISP new routers but less than 10 and usually on same channels.
I have fast transmissions of multimedia from computer-tv just using wifi... works very well.
i have it working on 5 and 10 mhz chainbw, but I cannot make work it on channels -1 and -2, any info:
iw phy0 info
Wiphy phy0
max # scan SSIDs: 4
max scan IEs length: 2257 bytes
max # sched scan SSIDs: 0
max # match sets: 0
max # scan plans: 1
max scan plan interval: -1
max scan plan iterations: 0
Retry short limit: 7
Retry long limit: 4
Coverage class: 0 (up to 0m)
Device supports AP-side u-APSD.
Device supports T-DLS.
Available Antennas: TX 0x3 RX 0x3
Configured Antennas: TX 0x3 RX 0x3
Supported interface modes:
* IBSS
* managed
* AP
* AP/VLAN
* monitor
* mesh point
* P2P-client
* P2P-GO
* outside context of a BSS
Band 1:
Capabilities: 0x11ef
RX LDPC
HT20/HT40
SM Power Save disabled
RX HT20 SGI
RX HT40 SGI
TX STBC
RX STBC 1-stream
Max AMSDU length: 3839 bytes
DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 8 usec (0x06)
HT TX/RX MCS rate indexes supported: 0-15
Frequencies:
* 2397 MHz [-2] (22.0 dBm)
* 2402 MHz [-1] (22.0 dBm)
* 2412 MHz [1] (22.0 dBm)
* 2417 MHz [2] (22.0 dBm)
* 2422 MHz [3] (22.0 dBm)
* 2427 MHz [4] (22.0 dBm)
* 2432 MHz [5] (22.0 dBm)
* 2437 MHz [6] (22.0 dBm)
* 2442 MHz [7] (22.0 dBm)
* 2447 MHz [8] (22.0 dBm)
* 2452 MHz [9] (22.0 dBm)
* 2457 MHz [10] (22.0 dBm)
* 2462 MHz [11] (22.0 dBm)
* 2467 MHz [12] (22.0 dBm)
* 2472 MHz [13] (22.0 dBm)
* 2484 MHz [14] (22.0 dBm)
valid interface combinations:
* #{ managed } <= 2048, #{ AP, mesh point } <= 8, #{ P2P-client, P2P-GO } <= 1, #{ IBSS } <= 1,
total <= 2048, #channels <= 1, STA/AP BI must match, radar detect widths: { 20 MHz (no HT), 20 MHz, 40 MHz }
the log when i set one of this two channels
Fri Oct 16 11:47:35 2020 daemon.notice netifd: radio0 (5255): cat: can't open '/var/run/wifi-phy0.pid': No such file or directory
Fri Oct 16 11:47:35 2020 daemon.notice netifd: radio0 (5255): WARNING (wireless_add_process): executable path /usr/sbin/wpad does not match process path (/proc/exe)
Fri Oct 16 11:47:35 2020 daemon.notice netifd: radio0 (5255): Command failed: Invalid argument
Fri Oct 16 11:47:35 2020 daemon.notice netifd: radio0 (5255): Device setup failed: HOSTAPD_START_FAILED
channels -1 and -2 does not work at all
it only work in monitor mode is thi a wpad or hostapd problem?
iw dev
phy#0
Interface wlan0
ifindex 14
wdev 0x9
addr xxxxxxxx
type monitor
channel -2 (2397 MHz), width: 20 MHz (no HT), center1: 2397 MHz
txpower 22.00 dBm
Because they are not in the International "unlicensed"/"licensed by regulation" portion of the 2.4. GHz band, hence inaccessible (that's the easy answer).
(Please note using a radio of of it's manufactured spec is illegal - I'm not considering the Amateur Licence, which the router can't guess you possess.)
hi ,yes (it work on channel 0) . 0 is the only one that is up , sometimes not, and sometimes up and down until it goes down again.
I'm just curios to understand how it works.
also in luci channel -1 = 255 and channel -2 =254
hi, i found a way to make it work. but i don't like it. because after a reboot the channel switch to another one. anyway that how i did that, via command line.
iw dev
phy#0
Interface wlan0
ifindex 6
wdev 0x2
addr xxxxxxxxxxx
ssid OpenWrt
type AP
channel 1 (2412 MHz), width: 20 MHz (no HT), center1: 2412 MHz
txpower 22.00 dBm
multicast TXQ:
qsz-byt qsz-pkt flows drops marks overlmt hashcol tx-bytes tx-packets
0 0 0 0 0 0 0 0 0
:~# ifconfig wlan0 down
:~# iw dev wlan0 set freq 2397
:~# ifconfig wlan0 up
:~# iw dev
phy#0
Interface wlan0
ifindex 6
wdev 0x2
addr xxxxxxxxxx
ssid OpenWrt
type AP
channel -2 (2397 MHz), width: 20 MHz (no HT), center1: 2397 MHz
txpower 22.00 dBm
multicast TXQ:
qsz-byt qsz-pkt flows drops marks overlmt hashcol tx-bytes tx-packets
0 0 0 0 0 0 0 0 0
any way to make this working after a reboot?
What device do you have?
I am unable to reproduce your result.
Add it to /etc/rc.local
hi lleachii, it work with every ath9k wlan, it work in mesh mode and monitor, but not in ap and station mode. i think we need touch hostapd to make it work in ap and station. anyway that was just for fun, long time now that i'm not playing with that.
you need patch mac80211.
if you need the patch i can share it.