Hi,
I am trying to set up my wrt1900acs to use the only non DFS 80 Mhz channel here in the UK. That channel has a centre frequency of channel 42. The LUCI interface does not offer that channel as an option. In fact changing the channel bandwidth does not seem to affect the channel numbers offered, these remain on the 20Mhz numbering scheme. The beacons that are actually broadcast are sent on the 20Mhz centre frequency set here. I have some vague recollection about the beacon being transmitted on the "nearest" 20Mhz in the standard, but i am not sure.
Is there a way to specify channel 42, or should I just set 40 or 44?
Any ideas?
Roger
[quote="rogerjames99, post:1, topic:2433"]e does not offer that channel as an option. In fact changing the channel bandwidth does not seem to affect the channel numbers offered, these remain on the 20Mhz numbering scheme. The beacons that are actually broadcast are sent on the 20Mhz centre frequency set here.[/quote]Start wifi as you were trying to use 80 MHz with central 42 and provide us output of:
iw dev wlan0 info
iw phy phy0 channels
(or use wlan1 & phy1 - depending on which card is 5 GHz one).
[rmilecki] rmilecki http://forum.openwrt.org/users/rmilecki
Rafał Miłecki http://forum.openwrt.org/users/rmilecki
March 18
rogerjames99:
e does not offer that channel as an option. In fact changing the
channel bandwidth does not seem to affect the channel numbers
offered, these remain on the 20Mhz numbering scheme. The beacons
that are actually broadcast are sent on the 20Mhz centre frequency
set here.
Start wifi as you were trying to use 80 MHz with central 42 and
provide us output of:
|iw dev wlan0 info iw phy phy0 channels|
(or use |wlan1| & |phy1| - depending on which card is 5 GHz one).
Here is the iw output.
root@peglegpete:~# iw dev wlan0 info
Interface wlan0
ifindex 49
wdev 0x22
addr c2:56:27:d4:a7:54
ssid peglegpete-high
type AP
wiphy 0
channel 36 (5180 MHz), width: 80 MHz, center1: 5210 MHz
txpower 20.00 dBm
root@peglegpete:~# iw phy phy0 channels
Band 2:
* 5180 MHz [36]
Maximum TX power: 20.0 dBm
Channel widths: 20MHz HT40+ VHT80
* 5200 MHz [40]
Maximum TX power: 20.0 dBm
Channel widths: 20MHz HT40- HT40+ VHT80
* 5220 MHz [44]
Maximum TX power: 20.0 dBm
Channel widths: 20MHz HT40- HT40+ VHT80
* 5240 MHz [48]
Maximum TX power: 20.0 dBm
Channel widths: 20MHz HT40- HT40+ VHT80
* 5260 MHz [52]
Maximum TX power: 20.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5280 MHz [56]
Maximum TX power: 20.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5300 MHz [60]
Maximum TX power: 20.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5320 MHz [64]
Maximum TX power: 20.0 dBm
Radar detection
Channel widths: 20MHz HT40- VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5500 MHz [100]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5520 MHz [104]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5540 MHz [108]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5560 MHz [112]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5580 MHz [116]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5600 MHz [120]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5620 MHz [124]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5640 MHz [128]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5660 MHz [132]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5680 MHz [136]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- HT40+ VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5700 MHz [140]
Maximum TX power: 27.0 dBm
Radar detection
Channel widths: 20MHz HT40- VHT80
DFS state: usable (for 20535 sec)
DFS CAC time: 60000 ms
* 5720 MHz [144] (disabled)
* 5745 MHz [149] (disabled)
* 5765 MHz [153] (disabled)
* 5785 MHz [157] (disabled)
* 5805 MHz [161] (disabled)
It looks like even though I am requesting an 802.11ac 80MHz channel, the
interface is using the old bgn channel numbering conventions. 802.11ac
changes the rules and just uses the centre frequency (channel number) to
name channels. However the centre frequency as shown is the correct one
(channel 42) 5000 + 42 * 5 = 5210. I might be useful to show this in the
UI. I checked, and even though I can select and apply any of the 20 MHz
channel numbers (36,40,44,48) the gui always shows the interface as set
to 36. Only if you go into edit mode can you the channel number set to
one of the above 4 possibilities. I find this a bit confusing, even
though the hardware seems to be configured correctly. My rtl-sdr
spectrum analyser (cheap clone) does not work very well at 5GHz so I
cannot properly verify is the transmission is actually at 5210. My
android wifi analyser shows it as channel 36 but I suspect that is wrong
as well.
Roger