On 01/16/2014 12:19 PM, Sujith Manoharan wrote: > Sujith Manoharan wrote: >> We could fix this by checking if we are initializing the history for the >> operating >> channel and waiting for NF-cal completion, but I am not sure if this needs >> to be done. The window is really small and subsequent NF calibrations using >> the ANI routine work properly. > Also, this is a bad idea in general since NF calibration has to > wait for the medium to become idle - problematic when there is heavy > interference or general WLAN usage. > > Sujith I guess I won't be able to reproduce bad scan results with wireless testing since I have changed scan reporting to pure rssi in my openwrt compat. In normal case you get a sum of rssi and noise floor and it will be correct i.e. when NF is shifted by 14db so will be rssi. So it's just my use case.
Anyway I have just solved the issue by applying calibrated noise floor values from eeprom instead of nominal in nf_get functions and nf histogram. Now the rssi seems stable in my test environment. I have just started testing but it looks promising. I don't know whether it's worth changing it upstream since most of available ar9003 cards I have seen are not noise floor calibrated. A bit bad becasue it could be used for spectral scan as well to improve accuracy. Wojtek _______________________________________________ ath9k-devel mailing list ath9k-devel@lists.ath9k.org https://lists.ath9k.org/mailman/listinfo/ath9k-devel
