Re: Question regarding Madwifi signal strength

[Dan Williams <dcbw redhat com>]

On Sat, 2007-06-09 at 00:11 +1200, Simon Geard wrote:
> On Fri, 2007-06-08 at 23:10 +1200, Simon Geard wrote:
> > On Thu, 2007-06-07 at 16:25 -0400, Darren Albers wrote:
> > > Do the above changes seem like they resolved these issues or maybe not
> > > affect it at all?   I can dig out my atheros card (it's in the attic!)
> > > and find out if nobody knows but I figured it would save me the hassle
> > > of climbing up there if someone already has checked.
> > 
> > I use an Atheros-based PCI card, so I'll try updating the drivers, see
> > if the signal strength is still an issue. As of whatever version I'm
> > running right now (SVN from about a month or two ago), NM reports about
> > 15% while the Gnome network applet shows about 60%. What would you
> > expect me to see on new drivers?
> 
> Ok, running the latest madwifi driver from SVN now. Doesn't seem any
> different from previous versions - I'm seeing roughly the same signals
> in NM as before. Is the following output from iwlist of any interest to
> you?
> 
>     00:17:9A:12:31:72 : Quality=49/70  Signal level=-46 dBm  Noise level=-95 dBm

                                  ^^^^ This looks wrong

Quality is supposed to be a linear value between 0 and max_qual.qual
inclusive.  49/70 = 70%; and with a signal of -46dBm and a noise of -95
dBm, that seems bogus.  It should be higher than that.  -46 dBm is
_really good_.

>     00:14:7C:AD:39:92 : Quality=120/70  Signal level=-256 dBm  Noise level=-95 dBm

                                  ^^^^ This is wrong

A value of 120 is clearly outside the bounds of 0, 70.

madwifi is free to use dBm or RSSI in the 'level' and 'noise' fields,
which it apparently does just fine (except for the -256 dBm signal level
in the above result).  But if the driver specifies quality, NM will use
that first, which it should do.

Dan

>     00:14:BF:3D:5F:ED : Quality=13/70  Signal level=-82 dBm  Noise level=-95 dBm
>     00:18:4D:05:20:D0 : Quality=4/70  Signal level=-91 dBm  Noise level=-95 dBm
>     00:16:E3:58:B0:C8 : Quality=3/70  Signal level=-92 dBm  Noise level=-95 dBm
>     00:0F:3D:B3:F0:68 : Quality=10/70  Signal level=-85 dBm  Noise level=-95 dBm
> 
> 
> Incidentally, I don't suppose you could point me to the patch for NM you
> referred to in your email?
> 
> Simon.
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