What’s this PDCCH layers?
4 PDCCH layers simultaneously for MU-MIMO.
For increasing PDCCH capacity.
This is how you need to spread the 5G users to achieve 16 PDSCH layers:
Answer is that pdcch beams are larges than pdsch beams
So you can have 4 pdcch beams to cover all 16 pdsch layers
So in a single slot Huawei is ablte to fetch 4 pdcch layers and 16 pdsch layers if 8 users can be paired for MU-MIMO scenario.
I read that some vendor are currently advertising 24 DL Layers…
Do you know which vendor?
Is it 4G or 5G?
4G Huawei has feature DL 24 layers.
And do you see in stats such a high number anywhere?
I found difficult even for 16 layers.
About 6 months ago, it was trial feature, now it is mature.
Yes, very few 16 layers MU-MIMO.
Recently Ericsson and T-mobile record 8 UE MU-MIMO 5G throughput total 5.6 Gbps.
They said theory is 5.9 Gbps.
Yes it is a must.
8 beams will not have high gain.
Figure is understood.
Actually position where users need to stand given by R&D.
Need to check for pdcch layers. Is it there?
Yes, they use live OSS traces to properly place users inside beam.
And for mcs27.
I remember for LTE MU-MIMO no concept of PDCCH layers seen.
Need to check for 5G.
UE at 8 SSB beam location?
UE at 8 PDSCH beams.
There are 3 types of beamforming.
Read here please:
PDCCH beamforming, where we can find?
I think it is often calculated UE location based on csi-rs beam location.
It is vendor feature, not mentioned by 3gpp I think.
It can be SRS to use EBB.
If it csi then it’s fixed weights used called GoB.
As of now srs reporting not used for NR.
UE report CSI and gNB apply fix weights.
We discussed earlier as well alongwith @RFSpecialist help in details.
Each AAU has a csi-rs beam pattern and people often base on it to estimate UE location for test, I think.
Again we mixed csi-rs with CSI-RS beams.
Both are different.
UE measure CSI-RS to report csi.
UE used csi-rs beams as well called refined beams.
1 ssb = 4 refined beams.
But it’s not always CSI-RS beams present in NR.
It can be enabled/disabled by switch.
Yes, we need to make a distinction between csi-rs ports, csi-rs reference signals and csi-rs beams.
3 distinct things.