Sudden Wi-Fi antenna changes

hvalles
Comes here often

Sudden Wi-Fi antenna changes

I have the following problem:

We have installed Meraki MR76 devices, which initially have good antenna strength.

Users connect to the Wi-Fi network without any problems. However, at random times, out of the 20 users who connect, 2 or 3 randomly lose connection and connect to another MR more distant, despite having a nearby antenna.

 

This happens randomly; they are not the same users; it always varies, but out of the 20, 2 or 3 have this incident.

 

We created a heat map and have seen that the antennas' spectrum is correct, and we don't see any co-channel interference.

 

What we have been able to detect are sudden changes in RSSI and SNR. Electromagnetic noise, or ROGUE, is probably causing unexpected roaming for some users.

 

Good roaming should occur before the RSSI or SNR reach very low values ​​to avoid dropouts. But some events show that the user waited until the signal strength was very poor before switching APs, for example:

 

Event:
RSSI: -84 -> -52
SNR: 11 -> 43

 

This means the signal strength was very poor before roaming, and improved significantly afterward. They probably waited too long to switch.

 

Something similar may have happened to you.

 

Thanks in advance.

 

Images attached.

 

Conexion Estable

Conexion estable.jpg

 

Eventos de Cambios de antena - Roaming

Roaming event 1.jpgRoaming event 2.jpgRoaming event 3.jpg

2 Replies 2
cmr
Kind of a big deal
Kind of a big deal

Roaming is decided by the client, what type of devices are they?  You might be able to configure them to roam earlier.

If my answer solves your problem please click Accept as Solution so others can benefit from it.
GIdenJoe
Kind of a big deal
Kind of a big deal

Have you measured between those 2 access points you give as an example?
For an example an Iphone will start looking to roam at -70 but the neighboring AP needs to be at least 10 dB higher at that point before it does so.  Perhaps you hare not having enough overlap.

Also if you are using MA-ANT-20 make sure the AP's are not mounted over 8 meters above ground.  Especially in the 5 GHz there is a large null zone at 45 degrees both above and below the antenna.

GIdenJoe_0-1744389849574.png

 

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