On 2018-02-14 17:26, Jean Pierre TOSONI wrote: > ath9k returns a wrong RSSI value for frames received in a 30ms time > window after a channel change. The correct value is typically 10dB > below the returned value. > > This was found with a Atheros AR9300 Rev:3 chip (WLE350NX / JWX6083 > cards), during offchannel scans. > > Mark the signal value as invalid in this case. > > Signed-off-by: Jean Pierre TOSONI <jp.tos...@acksys.fr> It seems that this will potentially cause a lot of scan results with RSSI information missing, which I think may be worse than a 10 db fluctuation. Actually, it could also be that the hardware is reporting accurate RSSI values (they're reported as SNR relative to the noise floor) and this is just a blip caused by the fact that the hw is updating its internal noise floor value based on running measurements.
Does the same fluctuation also happen if you set update = false for calls to ath9k_hw_start_nfcal? - Felix
