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signal column calculation

Posted: Mon Aug 19, 2013 1:35 pm
by proj964
hi,
i was trying to square the microsoft formula for signal vs vistumbler. wondered what algorithm you used in the calculation? here is the reference i found:
http://stackoverflow.com/questions/1579 ... o-rssi-dbm

Re: signal column calculation

Posted: Tue Aug 20, 2013 12:49 pm
by ACalcutt
In the current version of vistumbler (v10.3 and above), Native wifi mode has been made default and RSSI and Signal value are pulled right from the native wifi api. Native wifi uses 'uLinkQuality' for Signal and 'lRssi' for RSSI (see here for descriptions)

If you are using a older version of vistumber or you have native wifi mode off (Options --> Use Native wifi (unchecked)) then I used the following formulas to get an estimated RSSI value from signal % value

Code: Select all

Dim $dBmMaxSignal = '-30'
Dim $dBmDissociationSignal = '-85'

Func _SignalPercentToDb($InSig);Estimated value
	$dBm = ((($dBmMaxSignal - $dBmDissociationSignal) * $InSig) - (20 * $dBmMaxSignal) + (100 * $dBmDissociationSignal)) / 80
	Return (Round($dBm))
EndFunc   ;==>_SignalPercentToDb

Func _DbToSignalPercent($InDB);Estimated value
	$SIG = 100 - 80 * ($dBmMaxSignal - $InDB) / ($dBmMaxSignal - $dBmDissociationSignal)
	If $SIG < 0 Then $SIG = 0
	Return (Round($SIG))
EndFunc   ;==>_DbToSignalPercent
EDIT: The formulas mentioned were originally based off the following
http://www.ces.clemson.edu/linux/dbm-rssi.shtml

Re: signal column calculation

Posted: Tue Aug 20, 2013 4:43 pm
by proj964
I have native wifi mode selected, so i sent ms a note asking for an explanation...jon