Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 24 Jun 2007 22:38:16 +0100
From:      Andrew Liles <al@starfishzone.com>
To:        freebsd-questions@freebsd.org
Subject:   Re: What's the best diagnostic utility for wireless signal?
Message-ID:  <467EE448.2010301@starfishzone.com>
In-Reply-To: <4679877F.5040704@tundraware.com>
References:  <46797FE3.7030805@starfishzone.com> <4679877F.5040704@tundraware.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Tim Daneliuk wrote:
> Andrew Liles wrote:
>   
>> I use wireless on a FreeBSD 6.1 box in an area of low signal to my
>> Access Point.
>> I want to be able to inspect the signal strength/quality so that I may
>> adjust the antenna to get best results.  What is the best diagnostic to
>> use?
>>
>> For instance:
>>    wicontrol wi0
>> produces:
>> ...
>> Comms quality/signal/noise:             [ 28 47 1 ]
>> dBm Coms Quality:                       [ 14 -85 -99 ]
>> ...
>>
>> but what is "good" or which numbers should I be seeking maximise or
>> minimise?
>>     
>
> Here's a less analytical way that may work if you have marginal signal strength:
>
> 1) Connect wirelessly
> 2) Start pinging a site near you (to mimimize delay effects over the larger internet)
> 3) Move the antenna around to see where ping delays minimize across
>
> Similarly, you can do the same thing with traceroute which is even better because it
> shows delay at each step of the route.
>
> This is a quick-and-dirty scheme that may not always provide best results, but it's easy
> and a good way to get started....
>   
For the use of others:

By using a graphical meter on a Windows box, I tested different 
orientations of my Access Point.  Empirically I have found:

you get this when the Access Point is off:
Comms quality/signal/noise:        [ 0 0 1 ]
dBm Coms Quality:            [ 0 -100 -99 ]

this is when the signal is poor:
Comms quality/signal/noise:        [ 14 27 1 ]
dBm Coms Quality:            [ 7 -91 -99 ]

and this when signal is better:
Comms quality/signal/noise:        [ 52 83 1 ]
dBm Coms Quality:            [ 26 -73 -99 ]

So, in the absence of anything better information, I'd recommend you 
maximise each of the numbers shown in the above categories shown by the 
command:

wicontrol wi0

Doug points out that these numbers only appear with some drivers - mine 
is an "INTERSIL HFA384x" using the "wi" driver on FreeBSD 6.1





Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?467EE448.2010301>