ASUS RT-AX53U: Beamforming configuration

Installing and Using OpenWrt
1 
root@AX53U-S1:~# ubus call system board
{
	"kernel": "5.10.201",
	"hostname": "AX53U-S1",
	"system": "MediaTek MT7621 ver:1 eco:3",
	"model": "ASUS RT-AX53U",
	"board_name": "asus,rt-ax53u",
	"rootfs_type": "squashfs",
	"release": {
		"distribution": "OpenWrt",
		"version": "22.03.6",
		"revision": "r20265-f85a79bcb4",
		"target": "ramips/mt7621",
		"description": "OpenWrt 22.03.6 r20265-f85a79bcb4"
	}
}

root@AX53U-S1:~# grep vht_capab /var/run/hostapd*.conf
vht_capab=[RXLDPC][SHORT-GI-80][TX-STBC-2BY1][SU-BEAMFORMER][SU-BEAMFORMEE][MU-BEAMFORMER][MU-BEAMFORMEE][RX-ANTENNA-PATTERN][TX-ANTENNA-PATTERN][RX-STBC-1][SOUNDING-DIMENSION-2][BF-ANTENNA-4][MAX-MPDU-7991][MAX-A-MPDU-LEN-EXP7]

Reading https://openwrt.org/toh/asus/tuf-ax6000 I found

Beamforming and Basic Service Set (BSS) coloring

Beamforming improves data rates and extends range by directing signals toward specific clients instead of in every direction at once. By carefully controlling transmissions from several antennas, we can cause their signals to interfere on purpose and redirect the resulting signal in a new direction.

Basic Service Set (BSS) Coloring marks shared frequencies to allow 802.11ax access points to determine whether simultaneous use of spectrum is permissible. This technology reduces interference due to congestion and ensures consistent service to multiple connected devices in high-density environments.

Edit /etc/config/wireless and insert the following option under the radio section corresponding to the device which should be using beam forming:

config wifi-device 'radio1' ... option he_su_beamformee '1' option he_bss_color '8'

Restart wireless or reboot the device.

So are there recommanded settings for the ASUS RT-AX53U?

option he_su_beamformee '1'
option he_bss_color '??'

Edit: Looks like option he_bss_color is a random number, where you use a different one for each channel.

2

Looks like there is some automatic configuration.

root@AX53U-S1:~# grep -r beamform /tmp/run/
/tmp/run/hostapd-phy1.conf:he_su_beamformer=1
/tmp/run/hostapd-phy1.conf:he_mu_beamformer=1

What is beamformee ?

This is an output from a D-Link DAP-X1860

root@X1860-B1:~# grep -r beamform /tmp/run/
/tmp/run/hostapd-phy1.conf:he_su_beamformer=1
/tmp/run/hostapd-phy1.conf:he_su_beamformee=1
/tmp/run/hostapd-phy1.conf:he_mu_beamformer=1
/tmp/run/hostapd-phy1.conf.prev:he_su_beamformer=1
/tmp/run/hostapd-phy1.conf.prev:he_su_beamformee=1
/tmp/run/hostapd-phy1.conf.prev:he_mu_beamformer=1
3

Interesting thing. I was on 22.03.6 because of mentioned WAN-problems, but for the moment I do not need WAN. So I tried 23.05.2

root@AX53U-S1:~# ubus call system board
{
	"kernel": "5.15.137",
	"hostname": "AX53U-S1",
	"system": "MediaTek MT7621 ver:1 eco:3",
	"model": "ASUS RT-AX53U",
	"board_name": "asus,rt-ax53u",
	"rootfs_type": "squashfs",
	"release": {
		"distribution": "OpenWrt",
		"version": "23.05.2",
		"revision": "r23630-842932a63d",
		"target": "ramips/mt7621",
		"description": "OpenWrt 23.05.2 r23630-842932a63d"
	}
}

root@AX53U-S1:~# grep vht_capab /var/run/hostapd*.conf
vht_capab=[RXLDPC][SHORT-GI-80][TX-STBC-2BY1][SU-BEAMFORMER][SU-BEAMFORMEE][MU-BEAMFORMER][MU-BEAMFORMEE][RX-ANTENNA-PATTERN][TX-ANTENNA-PATTERN][RX-STBC-1][SOUNDING-DIMENSION-2][BF-ANTENNA-2][MAX-MPDU-7991][MAX-A-MPDU-LEN-EXP7]

And now the surprise:

root@AX53U-S1:~# grep -r beamform /tmp/run/
/tmp/run/hostapd-phy1.conf:he_su_beamformer=1
/tmp/run/hostapd-phy1.conf:he_su_beamformee=1
/tmp/run/hostapd-phy1.conf:he_mu_beamformer=1
/tmp/run/hostapd-phy1.conf.prev:he_su_beamformer=1
/tmp/run/hostapd-phy1.conf.prev:he_su_beamformee=1
/tmp/run/hostapd-phy1.conf.prev:he_mu_beamformer=1

There were changes with beamforming from Openwert 22 to 23.