Can't connect Raspberry Pi 3B+ Rev. 1.3 to Wifi 5G

[basti]

Hello,

i have a Raspi 3B+ and try to connect to WIFI 5G.

The Access Point is OpenWRT and operate in
AC mode, Channel 64 (5320 MHz).

On the pi side:

root@debian:~# cat /proc/device-tree/model ; echo " ";
Raspberry Pi 3 Model B Plus Rev 1.3
root@debian:~# iwlist wlan0 scanning| grep Freq
Frequency:2.412 GHz (Channel 1)
Frequency:2.437 GHz (Channel 6)
Frequency:2.437 GHz (Channel 6)
Frequency:2.462 GHz (Channel 11)
Frequency:2.462 GHz (Channel 11)
Frequency:2.462 GHz (Channel 11)

root@debian:~# iw reg get
global
country DE: DFS-ETSI
(2400 - 2483 @ 40), (N/A, 20), (N/A)
(5150 - 5250 @ 80), (N/A, 23), (N/A), NO-OUTDOOR, AUTO-BW
(5250 - 5350 @ 80), (N/A, 20), (0 ms), NO-OUTDOOR, DFS, AUTO-BW
(5470 - 5725 @ 160), (N/A, 26), (0 ms), DFS
(5725 - 5875 @ 80), (N/A, 13), (N/A)
(5945 - 6425 @ 160), (N/A, 23), (N/A), NO-OUTDOOR
(57000 - 66000 @ 2160), (N/A, 40), (N/A)

phy#0
country 99: DFS-UNSET
(2402 - 2482 @ 40), (6, 20), (N/A)
(2474 - 2494 @ 20), (6, 20), (N/A)
(5140 - 5360 @ 160), (6, 20), (N/A)
(5460 - 5860 @ 160), (6, 20), (N/A)

There is no Wifi 5G found.
I have no idea what is wrong there.

[Diederik de Haas]

On Friday, 17 November 2023 16:53:41 CET basti wrote:
> The Access Point is OpenWRT and operate in
> AC mode, Channel 64 (5320 MHz).

> ...

> root@debian:~# iw reg get
> global
> country DE: DFS-ETSI
> (2400 - 2483 @ 40), (N/A, 20), (N/A)
> (5150 - 5250 @ 80), (N/A, 23), (N/A), NO-OUTDOOR, AUTO-BW
> (5250 - 5350 @ 80), (N/A, 20), (0 ms), NO-OUTDOOR, DFS, AUTO-BW

If you specify a non-DFS channel, then it probably works.
I have a 'tab' open on [1] and [2] to research it further, but haven't
gotten around to it yet. So selecting a non-DFS channel is a workaround
but hopefully there is also an actual solution.

Asking on the OpenWrt forums is more likely to find a solution to this
problem then on this list (but maybe you're lucky).

[1] https://forum.openwrt.org/t/5-ghz-wlan-craps-out-upon-radar-detection-start-dfs-cac-failed/
[2] https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=cfd2f3bf6f4825b66e9a4ca9cba7c65b93eb89c7

[Tim Small]

If you're using the built-in wifi on the 3B, then I'm pretty sure it's
2.4GHz only. You'll need to use an add-on USB wifi adapter if you want
5GHz (maybe SDIO is also possible).

Tim.

[basti]

@Tim: 3B+ has b/g/n/ac dual band 2.4/5 GHz see
https://en.wikipedia.org/wiki/Raspberry_Pi#Specifications

@Diederik I'am not sure if OpenWRT is the Problem. Other clients can
connect to 5G Wifi. Or did you mean that Raspi does not Support DFS?

Am 17.11.23 um 19:07 schrieb Tim Small:

[gene heskett]

Its been yonks since I retired my 3b, but I don't recall it having 5G in
its radio, only the 2G 11 channel. And I can't scan with the rpi4b that
replaced it, nasty neighbor was stealing my bandwidth to the tune of
80Gigs a month, so all radios are disabled here. Karma caught up to him
and he did a year n the gov's economy hotel. His woman threw him out,
but I've never bothered to turn my radios back on, lots more peaceful
that way when you need a piece of cat6 to get into my machines.


Cheers, Gene Heskett.
--
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
- Louis D. Brandeis

[Diederik de Haas]

On Friday, 17 November 2023 19:58:22 CET basti wrote:
> @Diederik I'am not sure if OpenWRT is the Problem. Other clients can
> connect to 5G Wifi. Or did you mean that Raspi does not Support DFS?

I had to put my OpenWrt router on a non-DFS channel for 5G, otherwise I
couldn't connect to it. But if it works for you, then it's likely a different
issue.