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snabeel03
2011-12-29, 04:29 AM
All,

Any best practices/tips/strategies for improving CQI for LTE Systems?
Also,if UL throughput is low? Any suggestions for parameter tweaking or other opinions??

MINTO
2011-12-29, 07:10 AM
Hi Snabeel,

CQI is fixed as per modulation, so if you want to have batter CQI..improve your SINR.

you will using only 1 carrier, so try to remove overlapping ( reduce the number of server within 3, 5 & 10 Db).
also, if possible then make Your PCI plan as per MOD3,MOD6 & MOD30.

For uplink.

for parameters, i dont think you will be allowed to change :-(

i can recommend some parameters..on which vendor you are working??

from radio side below are the points to check.
–Uplink scheduling overview
–BSR (Buffer Status Report)
–PHR (Power Headroom Report) – is the UE at maximum power?
–Cell bandwidth vs. maximum allowable PRBs
–Link Adaptation
–MCS available and 16QAM
–PDCCH SIB scheduling colliding with UL grant

snabeel03
2011-12-29, 07:19 AM
Vendor is E*******.

MINTO
2011-12-29, 07:24 AM
ok..you can check these parameters .
›dlChannelBandwidth / ulChannelBandwidth
›(nrOfSymbolsPdcch) (Control Region Size) ß
›noOfUsedTxAntennas ß controls whether OLSM MIMO is used (2) or not.
›partOfRadioPower ß NOTE: this is the % part of RU capability independent of SectorEquipmentFunction::confOutputPower settings
›pZeroNominalPucch ß some UEs need this to be increased or ACK/NACKs are not received successfully on PUCCH.
›pZeroNominalPusch ß some UEs need this to be increased from default or lots of errors seen on PUSCH
–SectorEquipmentFunction=Sx
›confOutputPower / fqBand (readOnly)
–DataRadioBearer
›Various parameters for RLC status reporting and retransmission. Should be set to recommended values.
–MACConfiguration
›xxMaxHARQTx – enable (>1) or disable (1) HARQ. Recommended to use 4 HARQTx.
›tPeriodicBSRTimer – seen in UE testing to have some impact, recommend to set to 5ms.
›tTimeAlignmentTimer – seen in UE testing to have some impact, recommend to set to 5120ms

snabeel03
2012-01-11, 04:47 AM
How the PCI plan will improve CQI?

Any other suggestions for uplink throughput improvement?