Single user MIMO vs multi user MIMO

Regard to single user MIMO to multi user MIMO, what are difference between both modes?

Meaning lets say I have one cell with 32 UEs connected to it, running througput in all, then is it called multi-user MIMO?

MU-MIMO means when more / multiple users are scheduled using same slots and same PRBs, being space separated in different beams.

Everything else is SU-MIMO.

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Ahhh got you!

So assume it’s mu-mimo with 4 users.

Assume also max cell throughput is 500 Mbps.

So by mu-mimo mode, if let’s say each user is pumping 500 Mbps, then we can have 4 × 500 throughput.

But on su-mimo max throughput is 500 Mbps irrelative to how many UEs pumping max throughput (throughput is divided on users per slot ob that case).


With mu-mimo:

  • Capacity gain only seen in cell
  • Marginal cell throughout improvement
  • Avg user throughput degrade.

MIMO means using multiple antennas at transmitter and receiver.

If you have 4 channels (4 specially separated paths) at the transmitter, then you can use them for 1 UE or multiple UEs.

MU means multiple users.

MU-MIMO means putting more than 1 user spatially.

2 UEs are separated, not in frequency, not in time, but in space having the same time frequency resources.

If you have 4 channels you can give them to 4 UEs, 1 to each.

You can give them to 2 UEs, 2 channels to each.

You can give them to 1 UE, all 4 channels to 1 UE (this is SU-MIMO).