Intrafreq HO increase after dlRsBoost = -3dBm

[fahmi]

Hi,

We did the following tuning for L800 10M Cells to enhance DL Power of PDSCH RE.




Before (pMAX = 43dBm and dlRsBoost = 0dBm ) --> RS Power = 15.2dBm and PDSCH Power = 15.2dBm



After (pMAX = 46dBm and dlRsBoost = -3dBm ) --> RS Power = 15.2dBm and PDSCH Power = 18.2dBm


With the new setting, RS Power has not changed (15.2dB) and PDSCH RE power increased by 3dB and there was an improvement of CQI, Avg MCS PDSCH trans, Reported MIMO Rank2 Ratio and DL User Throughput.

But, the Intra frequency HO attempts increased and the Intra frequency HO SR degraded as shown in below plot.

Since our mobility strategy is totally based on RSRP (a3TriggerQuantityHO=RSRP) and RSRP is calculated based on RS Power for coverage handover, which in our case remains unchanged, how to explain the increase of Intra frequency HO attempts ?

43180

[coach]

Hi,

We did the following tuning for L800 10M Cells to enhance DL Power of PDSCH RE.




Before (pMAX = 43dBm and dlRsBoost = 0dBm ) --> RS Power = 15.2dBm and PDSCH Power = 15.2dBm



After (pMAX = 46dBm and dlRsBoost = -3dBm ) --> RS Power = 15.2dBm and PDSCH Power = 18.2dBm


With the new setting, RS Power has not changed (15.2dB) and PDSCH RE power increased by 3dB and there was an improvement of CQI, Avg MCS PDSCH trans, Reported MIMO Rank2 Ratio and DL User Throughput.

But, the Intra frequency HO attempts increased and the Intra frequency HO SR degraded as shown in below plot.

Since our mobility strategy is totally based on RSRP (a3TriggerQuantityHO=RSRP) and RSRP is calculated based on RS Power for coverage handover, which in our case remains unchanged, how to explain the increase of Intra frequency HO attempts ?

43180


Perhaps interference increased? Did you check RSRQ stats trend?

Even though handovers are based on RSRP, if interference increases then HO performance can degrade.

[fahmi]

Assuming Interference increased, what trigger those extra Intra freq Attempts ?

RSRQ HO is off

[djordjebeg]

Assuming Interference increased, what trigger those extra Intra freq Attempts ?

RSRQ HO is off
If you have no RSRQ triggered A3 you might have RSRQ filtered intrafrequency handover. If RSRQ increased after we have less prevented handover than before.
check if you have configured TGTTHRESHPR object under LNBTS and assigned to LNCEL( tgtThreshPrId)?

[fahmi]

Hi,

No TGTTHRESHPR is not configured for our network

BR,

[electron]

Hi,

No TGTTHRESHPR is not configured for our network

BR,

Hi,

I have seen similar behavior in Nokia footprint before as well. Any changes in User Plane or Signaling plane power will result degrading IntraF HO performance while in other vendors it is not visible. Based on my past experience RSRQ degradation causing the symptom. Try to tune filtering(RSRP, RSRQ) mechanisms to mitigate some unreliable HO decisions then you will be able to restore the HO Success rate


B
R