Quick question:
Do you guys see closed loop power control enabled on SA?
As per understanding we can use closed loop over SA, as well as most of parameter are common for SA and NSA, apart from few.
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Specs do allow it, agreed.
Question is whether NW vendors are currently supporting it on commercial networks.
Hi All.
Does anybody tested Close Loop Power Control in 5G, for PUSCH/PUCCH/SRS?
I have seen UL BLER degradation right after the activation.
If I can’t fix it, will disable CLPC in Nokia.
But this is what CLPC does, it increase the Uplink Power to reach a target BLER or a target SINR.
Your issue comes from surrounding cells.
Don’t forget that UE radiate omni.
So what goes to one cell it will go to other cells too.
In the overlapping area.
Can you please clarify youself a bit better?
Close loop power control aims to lower interference from other UEs.
What do you mean to degrade UL BLER? Why?
In my case, PUSCH/PUCCH SINR also degraded. only improved KPI is UE PHR.
UL bler degradation means thr degration in general so it is bad.
You look at CLPC just to decrease UE power, it acts also that it increases UE Power.
To reach a specific UL BLER or UL SINR.
And this increase on one cell damages the other cells in the overlapping area.
And for SRS degradation, there are so many parameters affecting SRS or based on SRS UL.
Have a look at Huawei parameters:
SRS Pre-SINR Judge Threshold
DL SRS MU-MIMO Space Isolation Threshold
SRS PreSINR Threshold
DL SRS MU-MIMO Freq Selection Threshold
DL SRS MU-MIMO PreSinr Threshold
SRS RSRP Threshold
SRS Power Control SINR Target
SRS PO
Max SRS PO Adjustment Amount
SRS Po Adaptation Period
Small-Packet UE SRS Pwr Ctrl SINR Target
Intrf UE SRS Pwr Ctrl Min SINR Target
SRS Carrier Switching Time DL Threshold
SRS Carrier Switching Time UL Threshold
SRS Switching Scc S Slot U Number
SRS Carrier Switching UL Symbol Config
UL SRS Measurement Usage Switch
SRS Interference Threshold
SRS Period
SRS Algorithm Switch
SRS Slot Number
SRS Algorithm Extension Switch
SRS Wideband Index Csrs
SRS Wideband Index Bsrs
SRS Narrowband Index Csrs
SRS Narrowband Index Bsrs
SRS Wideband to Narrowband Threshold
SRS Short Resource Allocate Policy
SRS Channel Period
Scenario-specific SRS Resource Alloc Policy
SRS Configuration Threshold
SRS Detection Algorithm Switch
Small Packet UE Maximum SRS Measure Period
Large Packet UE Maximum SRS Measure Period
SCG Rel UL SRS SINR Thld
SRS Transmit Port
SRS SINR Threshold
UL SRS Interference Difference Threshold
JT SRS RSRP Difference Threshold
CS/CBF SRS RSRP Offset
JT SRS Weight Enh RSRP Difference Threshold
SU-MIMO SRS Period Shortening Switch
SRS Precode Update Delay Reduction Policy
DL SRS DTX-based Precode Optimization Switch
SRS 1T Non-AS Precode Enhance Coefficient
SRS 2T Non-AS Precode Enhance Coefficient
SRS-based Weight Validity Period
SRS-based Weight Validity Period for Corr Calc
SRS RSRP Filtering Coefficient
DL Rank Adaptation SRS PreSINR Threshold
DL SRS MU-MIMO Rank
DL SRS MU-MIMO Rank Mode
SRS RSRP Diff-based DL Rank Selection Thld
SRS-based Weight Initial MCS Offset
Speed Turbo SRS P0 Offset
DL MU-MIMO SRS PreSINR Threshold
SRS and DMRS SINR Diff Thld
SRS RSRP Threshold
Carrier Selection TDD SRS RSRP Threshold
SRS RSRP Difference Threshold
Assistance SRS RSRP Thld
SRS Interference Difference Threshold
Qci-Specific SRS Period
SUL CoMP SRS RSRP Offset
Thanks, but irrelavant many of them, not changed SRS thresholds.
I am asking why in cluster level it degrades. What is the point?
Think like this: if one UE in one cell has to increase the power due to CLPC, then in the other cells (overlapping in that UE location) will increase Uplink interference.
Because interference goes in Uplink from a omni antenna of a UE.
So what does good to one cell it damages the other cells.
In open loop, ponominalpusch -92, srs: -92, when you switch to close loop why UL BLER is to be degraded?
UE pwr improves a lot which means now UEs are radiating at lower power in UL.
So there should be lower BLER.
Not higher.
BLER target is same in OPEN vs CLOSE loop, scheduler always try to approach %10. No difference.
You are studying just the case when CLPC reduces the power.
Think of the cases when it increases the power.
No, I am not studying this: Nokia was claiming UL thr improvent (slight) and improvement in bler with close loop.
It is opposite.
So I try to tune some parameters in close loop, like max sinr target.
If anyone have experience on this, please comment out. Otherwise it just confuse me more.
Have you checked cell overlapping in your cluster?
CLPC comes from CDMA, where overlapping was handled by soft handover.
In 2-way Soft the UL BLER was calculated at RNC from 2 backhaul paths, ecstatically reducing UL power due to cell diversity.
If a cell overshoots in your scenario the phone out there will be required to power up faster than closed loop, and will raise cluster UL BLER.
How does it sound like for you?
Sounds excellent.
I d check tpc commands how frequently sent. power headroom in cluster improved a lot, so basically UE approaches the %10 percent bler with less UL power than before. (before is open loop power control)
And when UE has less power in UL, actually bler in cell edge might increase. This is smth I dont want.
I want to improve bler at least %1, our bler is around 8% initial bler, already lower than 10, which is good.
Any more idea?
What is your ponom pucch value seems it’s very aggressive set.
5G FDD: -100 for PUCCH, -92 for PUSCH/SRS, 5G TDD: -90 for PUCCH, -92 for PUSCH/SRS, p0nominal for both.
alpha1
Yes value kept aggressive.
You can try with -110 for PUCCH to monitor hrly kpi.
Is overlapping high among nearby sectors?
Generally to maintain such high link UE radiate with high power leads to interfere injection for neighbour sector.
Yes high, intersite distance < 1km, but -110 PUCCH how will improve UL ber which i did not get well.
-110 PUCCH will definetely improve RSSI and interference but UL initial BLER is the question on my mind.
Reason for Poor Uplink:
- High over lapping among sectors
- Agressive value set for ponom pucch /pusch among sectors…UL sinr/rssi window fine tuning required to power up/down command to UE.
- External interference / repeaters lead to poor RSSI.
I will test it now in a cluster.
In my opinion what I was planning: to change alpha 1 to 0.8 and increase nominalpusch power.
Also good to mention that UL256 QAM is activated so more aggressive nominal PUCCH needed.
So the issue is more complex rather than in general Poor UL performance.