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New Member

Significance of the value of interference

Significance of the value of interference.

Ekahau SiteSurvey ver. 4.4.5, I did a site survey and I found a level of interefence equal to -100 dBm or smaller and a level of signal strength equal to -76dBm.

In monitoring of the intefaces the values is:

Interference by Channel

1 -128 dBm @ 0 % busy
2 -128 dBm @ 0 % busy
3 -128 dBm @ 0 % busy
4 -128 dBm @ 0 % busy
13 -128 dBm @ 0 % busy

Noise by Channel
1 -97 dBm
2 -97 dBm
3 -97 dBm
4 -97 dBm
13 -97 dBm

When I connected with my adapter and Intel PROSet, the supplicant indicated a level o signal strenght of -66 dBm and interference of -88dBm.

Ok, the adapter was not the same (ekahau with CAB21 Cisco and connectivity with Intel 5100), but why there are these difference of values in particular of interferense?


Mirko Severi.


Re: Significance of the value of interference

     There are several variable to the measured signal strength and noise values, but to be honest withyou I'd be inclined to think there is an issue with Ekahau since I rarely see a noise floor of -128dbm, -90 to -95 dbm is typical.  -88 isn't a bad number but I'd figure out why ekahau is reporting it wrong.
New Member

Re: Significance of the value of interference


I have made the site survey using the cardbus Cisco CAB21 (adapter supported of Ekahau) and the result was -100dBm so I expect that this value is right!!

My problem is that I have a unified wireless network with high density of APs and consequently a high interference, the client often disconnected.

I'd like to do a site survey and I'd see a higher value of interference but not so...


There is a method to measuse the level of the co-channel interference?

I have a ekahau 4.4.5 but I feat that it does not make this type of measurements correclty.

Somone had a similar experience?


Mirko Severi.