XV2-2 and XV2-2T0 very unstable performance in dense deployment

Hi all,

I completed installation in a multi-floor building, using (17x) XV2-2 and (1x) XV2-2T0. At any time, the maximum distance between a wifi client and an XV2-2 is no more than 5 meters (~15 feet). Clients achieve an SNR around 40db, interference is almost non-existent (cnMaestro reports noise floor as -100db and interference as -1). The internet access line is at 1Gbps.

Running a speed test with any wired laptop I can achieve 850Mbps. When I perform the same speed test on the same laptop (any laptop) using wifi however, I can achieve a tenth of that speed (80Mbps), at best! It actually fluctuates between 5Mbps and 80Mbps. Most laptops are wifi6 capable and are connected at 5Ghz. Weird thing is that the problem is not so bad with smart phones. Smart phones actually perform better than laptops!

The XV2-2T0 is installed on the roof (top of 7th floor) to cover the swimming pools area. Installation height (from the roof) is about 6 meters and the whole area to be covered is around 30meters x 15meters. The RF signal is mediocre, even when I am at a 10 meters distance with LoS! Most of the times I get the signal of another XV2-2 which is installed indoors instead.

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Turn off at least 1/2 of them, then retest.

This is something I could try but I am not sure if it will help as I don’t get reports for interference. I have tried playing with Roaming and setting SNR disconnection at 30db at 2.4Ghz and 27db @ 5Ghz. That did not help as I had disconnections at weak signal spots.

My deployments with Cambium have been limited due to technical issues.

However… In your post. The design you describe sounds like the builds I see from a competitor. TOO MANY APS, TOO CLOSE TOGETHER. That’s why I first recommended turning off about 1/2 of the APs.

I don’t know Cambium capabilities the way I know other vendors… Only from lack of use. But as a rule of “basic wireless”… 15 feet seems way over loaded. So I would start there. Turn on one AP. Do your testing with ONLY THAT ONE ON. Use that to develop a Baseline. Then from there, start working on expansion.

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Yellow,

It appears that you might have too many AP’s as other have alluded too. There could be other issues too.

  • Check frequency reuse and do manual setup
  • Lower power on each AP to suit the location
  • Check channel sizes (20MHz, 80MHz etc) there is only 6 Channels at 5GHz.

I’d also do a scan for other networks in the area; do you have a predictive heat map used?

Hope that might lead you down the right way

Let me know the below :

  • average distance between APs ?
  • number of floors ?
  • Country-code ? or AP output power in 2.4GHz and 5GHz ?
  • AP software version ?
  • AutoRF enabled ?

• average distance between APs ?
About 15 feet

• number of floors ?
Most of APs are at the top 3 floors of a 7 floor building. The 7 floor building is split vertically in the middle (virtually of course) to create 2 residences. All APs throughout the building broadcast the same 3 SSIDs.

There is some distance between this building and other buildings in the neighborhood so the signal I see from foreign APs is very weak (approximately -85dB).

The biggest issue is at floor 4.

• Country-code ? or AP output power in 2.4GHz and 5GHz ?
Country-code is CY (Cyprus). The AP power is set to auto for both 2.4GHz and 5GHz. I have also tried setting the 4th floor APs located at the edge of the building at 15db for both frequencies.

• AP software version ?
6.4.2.1-r1

• AutoRF enabled ?
Yes

I could share the heat map prediction I created with Cambium’s wifi designer before installation but I don’t see a way to do it here.

They may sound too many but they are separated by brick walls.
I am playing around with power which helped a little with roaming but not with performance stability.
Channel sizes are 20 for the 2.4GHz and 40 for the 5 GHz.
I think you mean there is only 6 channels at 2.4GHz? Because 5GHz have a lot more channels, right?
I do not have a proffesional channel scanner but seeing in cnMaestro what the APs report, there is no significant interference from foreign APs (I see some signals at -85db). I do have a predictive heat map and actual coverage seems to be as predicted.

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Hello,

In terms of 5GHz frequencies, please see below;

image

Hello Wireland,

I’ll be glad to jump in and help out here. Would it be possible to send me a Tech Support file from a few of the APs. I would like to review things like setup, rf environment, clients, etc. Please email to marc.hemann@cambiumnetworks.com.