test：openwrt19.07 and openwrt21.02
====================e1700ac（qca9563） 2X2==========
root@OpenWrt:/# iw wlan0 station dump
Station 8c:be:be:f5:8f:59 (on wlan0)
inactive time: 120 ms
rx bytes: 14835
rx packets: 296
tx bytes: 10450
tx packets: 90
tx retries: 1
tx failed: 0
rx drop misc: 0
signal: -57 [-62, -59] dBm
signal avg: -66 [-71, -69] dBm
===============e2600ac（ipq4019） 2x2===============
root@OpenWrt:/# iw wlan0 station dump
Station 8c:be:be:f5:8f:59 (on wlan0)
inactive time: 1160 ms
rx bytes: 3859
rx packets: 101
tx bytes: 2160
tx packets: 12
tx retries: 0
tx failed: 3
rx drop misc: 5
signal: -67 [-67, -77, -95, -95] dBm
signal avg: -74 [-74, -83, -95, -95] dBm
When using iw to view the connection information, it is found that the information displayed on the ipq4019 (e2600ac) is different from that of the mips (e1700ac). They are both 2x2 dual antennas.
ipq4019 displays 4-channel information (signal: -67 [-67, -77, -95, -95] dBm) and the next two display -95.
Is this normal?