Criteria for Mu-Mimo Operation A6?

Just curious what criteria is required to activate the Mu-Mimo operation of the A6? Is it a grouping thing based on location of the CPE? Signal? All of the above?

I ask because under the wireless statistics of the A6 there are no statistics for the MU columns. We have 9 CPE hooked to 1 of our A6’s. A total of 30 customers across 4 A6’s. I kept thinking that maybe there was a minimum CPE requirement before itd kick in, yet we have yet to see anything under the MU columns yet. Some insight would be appreciated!

For instance here is the dashboard of the A6 we are hooking 3 customers up to today (in addition to what is currently shown). As you can see the MU column is blank

On a side note, all of the customers are able to pull really close to the speed that is shown on the dashboard. The only one thats having some issues is the one labeled Jake Thomas. His speeds are pretty erratic ranging from 100 mbps up to 700 mbps. Sometimes it drops to 10 mbps and latency is all over the place. I probably shouldnt have hooked him up as hes close to the 11-12km mark. Im aware of the timing issues with this release of the firmware. This is a test environment though and we are doing just that, seeing what limits exist and what can be pushed a bit beyond whats stated. The one labeled montana gray will be moved to the peak of the house in a couple days when a lift is available, this cpe is definitely on a sidelobe and probably close to 10 degrees outside of the stated 90 degree beam pattern.

According to Mimosa’s own documentation for the C6 and A6 SU and MU stand from Single User Mimo and Multi User Mimo.

Client User Guide: Wireless Statistics (

Link Statistics

The Link Statistics page shows important information about a client’s Uplink and Downlink status. This can be used for troubleshooting connectivity issues with one or more clients.

  • Type - This shows the SU (single-user MIMO) and MU (multi-user MIMO) information for each client.

Access Point User Guide: Wireless Statistics (

Note: When the MU fields are populated for a client radio, this means that Multi User MIMO is active for that client.

The units in the picture are definitely spread out across the AP’s beam width. Even the one that now has 13 CPE on it are almost perfectly spread out from one side to the other with 3-4 units in each quadrant. All of the signal on that AP are above -65. If MU-Mimo was active you’d think that this grouping and signal levels would be as ideal as one could hope for

What is the distance of the CPEs from the A6 and what is the degree of spacing between C6 radios? Minimum distance is about 8 degrees between C6 radios.

The one I was referring to in a previous post has almost perfect spacing across the AP’s beam pattern. A total of 13 CPE, literally from one side of the beam to the other. They range in distance from about 4 miles up to around 9 miles.

The one in the picture are currently spread out around 60 degrees in the center. Theres one that is way out in the last 15 degrees or so of the beam from the ap. They range in distance from around 5 miles up to the 11 or so of the one I mentioned earlier that we shouldnt have hooked up.

This is 1 AP of 4 that we have. Close to 40 cpe now on those APs. Not one of the aps has anything populated in the MU column.

I can also confirm that my MU columns have no data or appear to indicate that there are no MU-MIMO instances. Attached is an A6 that show no MU info though these two C6 are 20degrees apart. Running 3.2.0 beta4 on all equipment and distance from A6 to C6 is 4-5km

EDIT: I also want to mention that im surprised with how low the SNR is for how strong of RSSI each C6 has. The spectrum is also clean, -85 across the band and adjacent channels which was just confirmed with A6 and C6 spectrum scanners. I was expecting high 20s or 30 SNR

I wish someone from Mimosa would comment and let us know something. Sorry I’m a little “gun shy” but I’ve already been down thus road with ubiquiti and LTU. The whole “its coming” game doesn’t suit very well with me. I’m $100k plus on an ltu network that should’ve delivered ofdma, 1024qam and a whole host of other crap.

Plus I noticed today on the AP that has the 15 (changing daily) cpe on it that we can’t get above 350mbps to any one customer. All of the wireless statistics say 1081or 1200 for the possible throughput. 30% of that isn’t real good. The AP’s that have 2-3 cpe can still pull around 600mbps. The ones that have 5-8 can pull around 450. There’s definitely a pretty steep drop off when you start loading it up which leads me to believe that MuMimo is not working properly.

The cause of this is a software BUG on TCP traffic, and it is known by the Mimosa team, if you try to run a test in UDP using for example iperf3 you will see that the speed is correct.
We have been waiting a long time for a fix to this BUG, unfortunately for now Mimosa doesn’t have a ready solution

We’re working on the TCP thing. I’m not sure if it’s in beta 5. I haven’t installed beta 5 since I have C5x radios in my setup.

As for MU-MIMO, the clients have to be in proximity to each other. For example:

You have 2 clients at 20 degrees apart that are roughly the same distance away. This would form an MU group. If you have 2 clients at 10 degrees apart but one is 1 mile and one is 4 miles away, this wouldn’t form an MU group.

So criteria for MU formation:

Minimum 5 degrees, maximum 30 degrees apart. Distance from the AP needs to be around the same distance. If you have clients closer together than 5 degrees (say like next door neighbors) then you might not have a group form between those two CPEs.

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So basically, the more loaded the AP the more of a chance you have of reaping the benefits from Mu-Mimo?

Finally was able to get something to populate in the MU column of the A6. Although im not real sure that i trust it. This AP has 26 CPE attached and as you can see, is showing 2 lol

On a side note—I seriously hope this TCP thing gets fixed soon! During peak hours we are struggling to be able to download 50mbps consistently behind any 1 CPE. Its gotten so bad we have stopped adding CPE to the unit as throughput is severely diminished! We are maxing out around 200-240mbps in total throughput in an 80mhz wide channel. There’s very little change in 40mhz or 160mhz