Wireless Access

Hi Guys,

Could the noise affect the RSSI?

Even the noise is very high, but I think it may not be able to affect the RSSI, right?

That is correct. But it'll affect the SNR. 

Thanks, 

Rajaguru Vincent 

Thanks,

But what would happen if  STA get a very high RSSI but a very low SNR?

Because in RF Optimization profile, the AP only measures the RSSI.

Does the AP send a deauth to the STA?

Hi, 

If RSSI is high, then SNR should also be high. 

For example, 

Noise floor =  -90 dBm

RSSI =  -35 dBm (high RSSI) 

SNR = 55 (high SNR) 

If RSSI is low, 

Noise floor = -90 dBm 

RSSI = -80 dBm (low RSSI) 

SNR = 10 (low SNR) 

In RF optimization profile, the RSSI threshold value can be 1-255. Here RSSI is not measured in dBm, but a relative measure of signal strength on a scale of 0-255. 

Thanks,

Rajaguru Vincent  

What if we increace the noise only, would the RSSI be affected by the high noise?

For example:

Noise floor =  -90 dBm

RSSI =  -35 dBm (high RSSI) 

SNR = 55 (high SNR) 

Some how, the noise floor increaced, maybe some one turned on a oven, then

Noise floor =  -50 dBm

Would the RSSI still be -35 dBM? 

Even if the RSSI still be -35 dBM, would the controller send a deauth to the STA because of the low SNR?

Hi, 

Noise floor usually won't go that high in real world. 

RF optimization profile will look at only the RSSI. Noise or the SNR change will not trigger a deauth. If RSSI goes low, it will trigger a deauth. 

Thanks, 

Rajaguru Vincent 

I think this a design flaw, Controller should measure bothe the SNR and RSSI. 

ClientMatch does that. RF optimization profile is an old one. 

Thanks, 

Rajaguru Vincent 

Thanks.

Yes , it's a ratio.

We shouldn't say RSSI = -35 dBM， but RSSI can be convert to Power Value.

Like RSSI 50* K = -35 dBM , every vendor have a different K value.