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Brad
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Noise-floor information

Wed Mar 01, 2006 8:50 am

Can someone (possibly from MT) please explain how the noise-floor information is calculated? I can run a snoop or freq-usage and find the absolute worst channel to operate on, setup my wlan on it and MT shows a -98 noise-floor and then change to a clear channel (low bandwidth usage) and it shows a -92.

Is anyone else having any luck using these values to determine clear channels? It would be nice to see some documentation on determining the best channel to operate on. There are so many tools now with the Scan, Freq. Usage, snooper, etc but no documentation to back them up.
 
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Equis
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Fri Mar 24, 2006 12:50 pm

I also was wondering this.

I have noise floor of -107 is that good or bad?

Is -90 better than -107 ? or teh other way around?

Thanks
 
Beccara
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Fri Mar 24, 2006 1:12 pm

From what i know the lower the better, -107 is ALOT better than -90
 
tully
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Sat Mar 25, 2006 11:27 am

The noise floor is only for non 802.11 activity on the spectrum. 802.11 traffic is not considered noise in this case.

John
 
taloot
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Sat Mar 25, 2006 11:54 am

me also i have -98 to -99 is that good or bad?
im using AMP 1 watt is that have effect on noise?
 
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ghmorris
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Sat Mar 25, 2006 7:32 pm

The noise floor is only for non 802.11 activity on the spectrum. 802.11 traffic is not considered noise in this case.

John
John, is Nstreme considered to be 802.11 for purposes of calculating the noise floor?

Thanks
George
 
tully
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Sun Mar 26, 2006 9:39 am

Yes, Nstreme uses the same frame encoding (ofdm...) as 802.11.

John
 
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ghmorris
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Sun Mar 26, 2006 1:54 pm

Yes, Nstreme uses the same frame encoding (ofdm...) as 802.11.

John
Thank you Sir. We are finding this new feature very useful.

George
 
rastod
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Fri Mar 31, 2006 7:24 pm

how exactly are you finding this new feature very useful?
 
ericsooter
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Fri Mar 31, 2006 9:54 pm

Because it gives you a clear picture of non-802.11 noise. This could be from propietery wifi stuff, cordless phones, noisy transformers, etc. Not sure if it detects out-of-band harmonics.

Eric
 
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ghmorris
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Fri Mar 31, 2006 10:42 pm

Exactly. Now if we could only have a "spectrum analyzer" type display for noise floor across all the channels life would be truly wonderful.

Check out an Orthogon Gemini for an example of doing it right. Signal strengths and noise floor on a single display across all channels.

George
 
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jp
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Tue Apr 04, 2006 5:37 pm

Here is a spectrum analyzer from the Alvarion 900mhz equipment. The display is cumulative, and in this case, it's been scanning for 6 minutes. It shows average and peak signal levels.

Image

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