Xiaomi Mi Router 4A (Giga) no switch and noise level measurement?

[ichaban]

Hello,
I recently installed Xiaomi Mi Router 4A Gigabit (21.02.1) as a Dumb AP. In this regard, two questions appeared:

• I noticed that there is no "Switch" menu in LuCI. Does it really have no hardware switch? What if I need to configure some VLANs?
• Is it not capable of measuring noise level? iwinfo shows something like this. If so, how does it determine Link Quality without knowing the noise level? All these numbers are just fiction then?

wlan0     ESSID: "********"
          Access Point: ********
          Mode: Master  Channel: 13 (2.472 GHz)
          Center Channel 1: 11 2: unknown
          Tx-Power: 20 dBm  Link Quality: 54/70
          Signal: -56 dBm  Noise: unknown
          Bit Rate: 150.0 MBit/s
          Encryption: WPA2 PSK (CCMP)
          Type: nl80211  HW Mode(s): 802.11bgn
          Hardware: 14C3:7603 14C3:7603 [MediaTek MT7603E]
          TX power offset: none
          Frequency offset: none
          Supports VAPs: yes  PHY name: phy0

wlan1     ESSID: "********"
          Access Point: ********
          Mode: Master  Channel: 149 (5.745 GHz)
          Center Channel 1: 155 2: unknown
          Tx-Power: 20 dBm  Link Quality: 60/70
          Signal: -50 dBm  Noise: unknown
          Bit Rate: 263.3 MBit/s
          Encryption: WPA2 PSK (CCMP)
          Type: nl80211  HW Mode(s): 802.11nac
          Hardware: 14C3:7662 14C3:7662 [MediaTek MT76x2E]
          TX power offset: none
          Frequency offset: none
          Supports VAPs: yes  PHY name: phy1

[slh]

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