On Tue, 2008-03-18 at 00:44 +0000, Jonathan Underwood wrote: > On 18/03/2008, Jonathan Underwood <jonathan.underwood@xxxxxxxxx> wrote: > > On 17/03/2008, Timothy Murphy <gayleard@xxxxxxxxxx> wrote: > > > John W. Linville wrote: > > > > > > >>> > Well if I out my mouse pointer on the nm-applet icon I get the > > > message: > > > >> > Wireless Network Connection to ??? (98%) > > > >> > I assume 98% is a measure of signal strength. > > > >> > > > >> I can't think of anything it could possibly be 98% of ... > > > > > > > > That's probably because you are intentionally obtuse, and apparently > > > > on a jihad against NetworkManager... > > > > > > > > > I'm unintentionally obtuse. > > > What is this signal strength 98% of? > > > > > > > > > I'd guess it means that 98% of the transmitted signal intensity is > > being received by the wireless card. Although I have to admit, I do > > wonder how that is calculated, and whether it takes into account the > > 1/r^2 fall off of signal emitted in the full sphere. > > > > Actually, for those that are interested: > > http://www.wildpackets.com/elements/whitepapers/Converting_Signal_Strength.pdf > > explains things fairly well, although how this "link quality" > percentage is calculated is rather opaque. It seems to be some > aggregate value of signal strength, signal-to-noise and various other > factors. May also be vendor dependent. According to iwconfig manpage: > > "Overall quality of the link. May be based on the level of contention > or interference, the bit or frame error rate, how good the received > signal is, some timing synchronisation, or other hardware metric. > This is an aggregate value, and depends totally on the driver and > hardware." > > In any case, it seems it's a value exposed by the kernel in /proc/net/wireless. See also the bottom three articles at http://www.ces.clemson.edu/linux/ for some other interesting material. > > J. > > -- Matthew Saltzman Clemson University Mathematical Sciences mjs AT clemson DOT edu http://www.math.clemson.edu/~mjs
