How are beams separated in Uplink?

[Hainm]

I think CPE.

[RFSpecialist]

Where does it says that this is used in CPE and not in gNodeB?
Yes, it is used in CPE.

[Hainm]

But mmWave gNB almost no support UL MU-MIMO?

[RFSpecialist]

I think at Huawei UL MU-MIMO is possible only for low frequency TDD cells with 32T32R or 64T64R or higher.

[Manoj_deka]

@RFSpecialist

In DL is easy: signal of one UE is in a DL beam that is very little interfered by other DL beams due to orthogonality.
In Uplink all signals reach the UE in same location. So even if we have 3 UEs separated at 2 km one from another (just an example) in Uplink will reach the gNodeB in same location.

In case of UL, RBs will be allocated to the paired UEs by the eNB using the DCI format 0_1.
In MU MIMO, the same set of RBs will be allocated to every paired UEs.
So, I think there is a DMRS sequence in DCI format 0_1 which will be used by every UE when sending the UL data.
From this DMRS sequence, the eNB will decode the PUSCH for every UE.

Don’t know whether I am correct or wrong…