How much do the number of MIMO antennae affect performance?

[oxwivi]

While considering new devices for an office, I got to think about switching out my personal Belkin RT3200 with a Filogic WR3000S. My service recently upgraded to 1 Gbps, and I can't enable either software or hardware offloading due to bugs in conntrack messing with WireGuard connection in roaming clients. I was hoping Filogic would give me more of a headroom in that regard.

But while looking into the details, I noticed WR3000S apparently only has 2x3:2 MIMO antennae, as opposed to RT3200's 4x4:4. How should I expect the Wi-Fi performance to be affected if I go ahead with WR3000S?

@golialive

To my knowledge, both devices should have nearly identical performance. In the 5GHz range, they should have exactly the same performance, and in the 2.4GHz range, they are very close.

I currently have two of these literally side by side, and while my devices tend to prefer the Cudy a bit better, I personally can't tell the difference if my MacBook or my Samsung S22 are connected to either of them.

Per the quote, the performance appears to be identical, but that raises more questions for me. What does the antennae even do if the performance remains unaffected?

PS I used to see MU-MIMO marketing a lot. Curious why MU is never mentioned in any sort of specs for such APs.

[badulesia]

@oxwivi

How should I expect the Wi-Fi performance to be affected if I go ahead with WR3000S?

Hi.
I'm using the WR3000S and a laptop with intel AX201 wifi card. LAN to LAN transfers (large files) can be done at 110 MB/s, that means full Gb/s capability from the LAN port.
That being said, the laptop is only a few meters away from the router, mainly alone, and I have no neighborhood issues. I don't know what to expect when several devices are linked.

[brada4]

Depends on how many antennas clients have. MU-MIMO can work with stationary (as opposed to walking) clients that get into a lucky beamforming spots. e.g. network mesh extenders, not people with phones walking around.

Simplified model - you drop 2 stones into a pond. You see the max amplitude "beams". Can you get two reeds in those beams... at once. That's the 2x2 MU-MIMO. in 2 dimensions, not 3.

[oxwivi]

So for MIMO to give clients a boost, they would need to be both stationary and at specific location?

Without meeting the two conditions, is it as good as not having any MIMO magic? But then isn't the same implemented in cellular networks? It appears to be quite crucial in that space.

[brada4]

The multi-user mimo needs multiple users to decode same air frame in different points. mimo means various sets of antennas serve different users at once. eg 2-antenna router serves 2 1-antenna clients at once fully.