Wifi station Bandwidth 160MHz / 80MHz control (linux)

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I observe wifi station TX bandwidth to be reduced from 160MHz to 80MHz while the station is farther away versus it is closer to AP. I'm using "iw wlan0 station dump" command to check that. AP is forced to 160MHz and it actually use 160MHz for downlink for both cases. But the AX200 station is using 80MHz for uplink after the RSSI is lower than say about -60dBm. I've checked this with Intel AX200 card. To confirm this is not a card related I also checked Broadcom Xeon 1200 card. Same here. Also a number of different AP was tested. All results are consistent. Since Intel AX200 uses Intel proprietary Rate Control Algorithm "iwl-mvm-rs" and Broadcom use some other, I know the bandwidth limitation must be introduced by linux itself (mac80211 / cfg80211?). Which part it could be? Can I fix it to 160MHz? This bandwidth reduction is probably the part of Rate Control Algorithm but the strange thing is that AP downlink bitrate is for example 500Mbits/s (160MHz) while in the same time uplink is 250Mbits/s (80MHz). On the closer locations the bitrate is the same e.g. 1000Mbits/s (160MHz) for both downlink and uplink. Thus this might be some kind of a bug to reduce the bandwidth too early.

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