This document summarizes various LTE KPIs and performance metrics related to random access, RRC connection establishment, ERAB establishment, and issues that may impact them. It provides potential causes for high values or failures in these metrics as well as recommended actions to investigate like checking RF parameters, capacity, licenses, alarms, configuration, and optimizing physical antenna settings.

1. LTE KPI
Accessability
Random Access
Contention Based random Access (CBRA)
pmRaAttCbra , pmRaSuccCbra
pmRaFailCbraMsg2Disc , pmRaFailCbraMsg1DiscOoc
pmRaFailCbraMsg1DiscSched
rachRootSequence , cellRange
qRxLevMin , preambleInitialReceivedTargetPower
powerRampingStep (Hardcoded) , preambleTransMax (Hardcoded)
numberOfRA-Preambles (Hardcoded)
Improve RF conditions (by parameters or physical optimization (tilt/azimuth/antenna height))
Check RSI planning (ex. For 15km cell range, diff of 10 between 2 neighbours)
Tune RACH related parameters , also check symptoms for sleeping cell (mentioned below)
Contension Free Random Access (CFRA)
pmRaAttCfra
pmRaSuccCfra
pmRaFailCfraMsg2Disc
pmRaAllocCfra
pmRaUnassignedCfraFalse
pmRaUnassignedCfraSum
pmRaFailCfraMsg1DiscOoc
pmRaFailCfraMsg1DiscSched
rachRootSequence , cellRange
qRxLevMin , preambleInitialReceivedTargetPower
powerRampingStep (Hardcoded) , preambleTransMax (Hardcoded)
numberOfRA-Preambles (Hardcoded)
Improve RF conditions (by parameters or physical optimization (tilt/azimuth/antenna height))
Check RSI planning (ex. For 15km cell range, diff of 10 between 2 neighbours)
Tune RACH related parameters , also check symptoms for sleeping cell (mentioned below)
SSSR (Session setup sucess rate)
RRC connection
pmRrcConnEstabAtt
(pmRrcConnEstabAttDta , pmRrcConnEstabAttEm
pmRrcConnEstabAttHpa , pmRrcConnEstabAttMod
pmRrcConnEstabAttMos , pmRrcConnEstabAttMta)
pmRrcConnEstabAttReatt
(pmRrcConnEstabAttReattDta , pmRrcConnEstabAttReattEm
pmRrcConnEstabAttReattHpa , pmRrcConnEstabAttReattMod
pmRrcConnEstabAttReattMos , pmRrcConnEstabAttReattMta)
pmRrcConnEstabSucc
(pmRrcConnEstabSuccDta , pmRrcConnEstabSuccEm
pmRrcConnEstabSuccHpa , pmRrcConnEstabSuccMod
pmRrcConnEstabSuccMos , pmRrcConnEstabSuccMta)
Capacity cause
MP load
pmRrcConnEstabFailHighLoad (MP load control)
pmRrcConnEstabFailOverload (procedure latency supervision)
pmRrcConnMax , pmRrcConnLevSum
pmProcessorCoreLoad , pmProcessorLoad
pmProcessorLoadDistr
noOfPucchCqiUsers , noOfPucchSrUsers , pdcchCfiMode
tInactivityTimer , dlMaxRetxThreshold , ulMaxRetxThreshold
qOffsetcellEUtran , qRxLevMin , SchedulingAlgorithm , crsGain
tPollRetransmitUl (DRB & SRB) , tPollRetransmitDl (DRB & SRB)
numInitialAccessAndIncomingHo (system constant) , SpdcchLaGinrMargin (system constant)
ulInterferenceForgettingFactor (system constant) , deltaPsdRs2Tx (system constant )
Tune parameters as mentioned beside.
Physical changes (Tilt , Azimuth , height of antenna)
Reduce size of TA , reduces no. of cells being paged so reduces the CPU load in the MP.
MP capacity of DUS is higher than DUL , to increase MP capacity DUL can be replaced by DUS
Reduce no. of HO by physical opti or features (UE Level Oscillating Handover Minimization & Automated Mobility Optimization
Tune cell reselection parameters to offload traffic to nearby cells
License
pmRrcConnEstabFailActiveUserLicenseExceeded
pmActiveUeDlSum
pmActiveUeDlSectorCarrierDistr
pmActiveUeDlMax
pmActiveUeDlSumQci
pmActiveUeUlSum
pmActiveUeUlMax
pmActiveUeUlSectorCarrierDistr
pmActiveUeUlSumLcg
noOfPucchCqiUsers , noOfPucchSrUsers , pdcchCfiMode
tInactivityTimer , dlMaxRetxThreshold , ulMaxRetxThreshold
qOffsetcellEUtran , qRxLevMin , SchedulingAlgorithm , crsGain
Tune parameters mentioned aside
Physical changes (Tilt , Azimuth , height of antenna)
Tune cell reselection parameters to offload traffic to nearby cells
pmRrcConnEstabFailLic
pmLicConnectedUsersLicense , pmLicConnectedUsersTimeCong
pmLicConnectedUsersHardLimit , pmLicConnectedUsersActual
pmLicConnectedUsersDistr
noOfPucchCqiUsers , noOfPucchSrUsers , pdcchCfiMode
tInactivityTimer , dlMaxRetxThreshold , ulMaxRetxThreshold
qOffsetcellEUtran , qRxLevMin , SchedulingAlgorithm , crsGain
Upgrade license for number of connected users
Physical changes (Tilt , Azimuth , height of antenna)
Tune parameters as mentioned beside.
Radio Cause pmRrcConnEstabFailFailureInRadioProcedure
Poor DL SINR (CQI) pmRadioUeRepCqiDistr , pmRadioUeRepCqiDistr2
maximumTransmissionPower
partOfSectorPower
confOutputPower
crsGain
pdschTypeBGain
Tune related parameters (as mentioned beside) , Physical optimization (Tilt , Azimuth , height of antenna
Identify overshooting cells causing interference in DL , Audit cell reselection parameters
Coverage issues
pmBadCovEvalReport
pmRadioTbsPwrRestricted
pmBadCovSearchEvalReport
maximumTransmissionPower
partOfSectorPower
confOutputPower
crsGain
pdschTypeBGain
Indoor coverage issue (Small cell , PICO , DOT , Hetnet)
Physical changes (Tilt , Azimuth , height of antenna)
Audit cell reselection parameters & Tune DL power related parameters (as mentioned beside) also Check if there is scope of new site
UL RSSI
pmRadioRecInterferencePwr
pmRadioRecInterferencePwrPucch
pmRadioRecInterferencePwrPrb1~100
pmSinrPucchDistr , pmSinrPuschDistr
pZeroNominalPucch
pZeroNominalPusch
Check Power control parameters
Features like IRC & UL FSS can help to reduce UL interference.
Check for Loose Connectors,Faulty Antenna(Tx & Rx antenna ports),VSWR alarms,Faulty TMA Connections/settings.
External interference (cable tv , repeaters (due to power leak issues) , airport , police communication system etc..)
Other Causes
pmRrcConnReestFailLicMtReest pegged due to lack of license of feature Multi-Target RRC Connection Reestablishment
pmRrcConnEstabFailLackOfResources
pmPrbUtilDl
pmPrbUtilUl
noOfPucchCqiUsers , noOfPucchSrUsers , pdcchCfiMode
tInactivityTimer , qRxLevMin , dlMaxRetxThreshold
ulMaxRetxThreshold , qOffsetcellEUtran
SchedulingAlgorithm , crsGain
Tune parameters mentioned aside
Physical changes (Tilt , Azimuth , height of antenna)
Tune cell reselection parameters to offload traffic to nearby cells
pmRrcConnEstabFailUnspecified Mainly pegged due to eNB issues
pmRrcConnEstabFailBearerAdmissionRej
(SRB admission control)
PmPdcchCceUtil
pdcchAdmThreshold , noOfPucchCqiUsers , noOfPucchSrUsers
pdcchCfiMode , tInactivityTimer , qRxLevMin
dlMaxRetxThreshold , ulMaxRetxThreshold
qOffsetcellEUtran , SchedulingAlgorithm , crsGain
SRB admission control
Tune parameters mentioned aside
Physical changes (Tilt , Azimuth , height of antenna)
Tune cell reselection parameters
MME overload
pmRrcConnEstabFailMmeOvlMos
pmRrcConnEstabFailMmeOvlMod
Check parameters related to MME Overload Control feature & MME Dimensioning
Other checks
Low number of attempt
If there are more then 1 carrier optimize load balancing parameter
Optimize tilt/azimuth/antenna height to balance traffic from near by sites
check for alarms or other hardware issues
Availability
Cell down
Cell Down Auto
pmCellDowntimeAuto
pmCellDownLockAuto
eNodeB Cause
Configuration issues ensure proper configuration , especially for all new site which are integrated recently
Auto Restart
Ensure the eNodeB structure of the restart, MP、Baseband or RRU
lh all llog -l (do complete eNB health checkup)
Baseband Startup issue Baseband Trace can be used , te enable all bbmcBbOmMeSwU
Transport Cause S1 issues pmErabRelAbnormalEnbActTnFail check for alarms like Service Unavailable(S1 connection failure)
EPC Cause check for alarms like Service Unavailable(S1 connection failure) , Ip packet loss "above" SGW
Cell Down Manually
pmCellDowntimeMan
pmCellDownLockMan
Operation Cause
manually locked during network configuration issues ((eg. adding/changing/removing hardware)
manually locked during parameter change (eg. activate feature)
Sleeping Cell
pmRaAttCbra
pmRaSuccCbra
pmRaFailCbraMsg2Disc
pmRaAttCfra
pmRaSuccCfra
pmRaFailCfraMsg2Disc
pmRaAllocCfra
pmRrcConnEstabAtt
pmRrcConnSucc
Verify symptoms for sleeping cell
Trace(Baseband) trace from MSG1 to MSG5 , verify symtoms for sleeping cells
Non-access issue
Configuration issue
Power setting issue Check SectorEquipmentFunction:ConfiguredOutputPower & Eutrancelltdd:partOfSectorPower
Idle mode parameter issue Check Eutrancelltdd MO cell selection and reselection parameters & 3G&2G cell reselection parameter/feature
Operation issues Cell Barred Check Cell Barred , acBarring for different scenarios
HW Cause
Alarms
Common alarm : "resource configuration disable" , RRU fault , link failure , Check current & history alarms & take necessary action according to type of Alarm
Check RRU status , Reset boards , Verify SW on node
S1 links down due to faulty interface board.
VSWR CABX , verify VSWR on all ports of antenna
TMA check Faulty TMA Connections & faulty settings
S1 SIGNALLING CONNECTION
PmS1SigConnEstabAtt
(pmS1SigConnEstabAttHpa , pmS1SigConnEstabAttMod
pmS1SigConnEstabAttMta , pmS1SigConnEstabAttMos
pmS1SigConnEstabAttDta , pmS1SigConnEstabAttEm)
PmS1SigConnEstabSucc
(pmS1SigConnEstabSuccEm , pmS1SigConnEstabSuccHpa
pmS1SigConnEstabSuccMod , pmS1SigConnEstabSuccMta
pmS1SigConnEstabSuccMos , pmS1SigConnEstabSuccDta)
pmS1SigConnEstabFailMmeOvlMos Check MME signalling dimensioning
Other Checks
TN issue Check S1 interface , S1 links down due to faulty interface board
TAC wrong configure & LAC-TAC mapping Configure Correct TAC as per planning & ensure correct TAC LAC Mapping
CN abnormal release Cell trace and check with Core Engineer
ERAB ESTABLISHMENT
PmErabEstabAttInit
(pmErabEstabAttInitArp , pmErabEstabAttInitPa)
PmErabEstabSuccInit.
(pmErabEstabSuccInitArp , pmErabEstabSuccInitPa)
PmErabEstabAttAdded
(pmErabEstabAttAddedArp , pmErabEstabAttAddedPa)
PmErabEstabSuccAdded
(pmErabEstabSuccAddedArp , pmErabEstabSuccAddedPa)
pmErabEstabAttAddedHoOngoing
pmErabEstabAttAddedHoOngoingArp
PM Counter
pmErabEstabFailGbrDlEnb dlNonGbrRatio , dlTransNwBandwidth Tune Dynamic GBR Admission Control related parameter
pmErabEstabFailGbrUlEnb ulNonGbrRatio , ulTransNwBandwidth Tune Dynamic GBR Admission Control related parameter
License
pmErabEstabFailAddedLic Check license & Feature state of Multiple Radio Bearer per user or RLC UM
pmErabEstabFailInitLic Check license & Feature state of Multiple Radio Bearer per user or RLC UM
pmErabModFailLic Lack of license of Dynamic QoS Modification
Radio Cause
Poor DL SINR (CQI)
pmRadioUeRepCqiDistr
pmRadioUeRepCqiDistr2
maximumTransmissionPower
partOfSectorPower
confOutputPower
crsGain
pdschTypeBGain
Tune related parameters (as mentioned beside) , Audit cell reselection parameters
Physical optimization (Tilt , Azimuth , height of antenna)
Identify overshooting cells causing interference in DL
Coverage issues
pmBadCovEvalReport
pmRadioTbsPwrRestricted
pmBadCovSearchEvalReport
maximumTransmissionPower
partOfSectorPower
confOutputPower
crsGain
pdschTypeBGain
Indoor coverage issue (Small cell , PICO , DOT , Hetnet)
Physical changes (Tilt , Azimuth , height of antenna)
Audit cell reselection parameters & Tune DL power related parameters (as mentioned beside) also Check if there is scope of new site
UL RSSI
pmRadioRecInterferencePwr
pmRadioRecInterferencePwrPucch
pmRadioRecInterferencePwrPrb1~100
pmSinrPucchDistr , pmSinrPuschDistr
pZeroNominalPucch
pZeroNominalPusch
Check Power control parameters
Features like IRC & UL FSS can help to reduce UL interference.
Check for Loose Connectors,Faulty Antenna(Tx & Rx antenna ports),VSWR alarms,Faulty TMA Connections/settings.
External interference (cable tv , repeaters (due to power leak issues) , airport , police communication system etc..)
Other checks HW Cause
Availability
Cell down
Cell Down Auto
pmCellDowntimeAuto
pmCellDownLockAuto
eNodeB Cause
Configuration issues ensure proper configuration , especially for all new site which are integrated recently
Auto Restart
Ensure the eNodeB structure of the restart, MP、Baseband or RRU
lh all llog -l (do complete eNB health checkup)
Baseband Startup issue Baseband Trace can be used , te enable all bbmcBbOmMeSwU
Transport Cause S1 issues pmErabRelAbnormalEnbActTnFail check for alarms like Service Unavailable(S1 connection failure)
EPC Cause check for alarms like Service Unavailable(S1 connection failure) , Ip packet loss "above" SGW
Cell Down Manually
pmCellDowntimeMan
pmCellDownLockMan
Operation Cause
manually locked during network configuration issues ((eg. adding/changing/removing hardware)
manually locked during parameter change (eg. activate feature)
Sleeping Cell
pmRaAttCbra
pmRaSuccCbra
pmRaFailCbraMsg2Disc
pmRaAttCfra
pmRaSuccCfra
pmRaFailCfraMsg2Disc
pmRaAllocCfra
pmRrcConnEstabAtt
pmRrcConnSucc
Verify symtoms for sleeping cell
Catch Trace(Baseband) trace from MSG1 to MSG5 , verify symtoms for sleeping cells
Non-access issue
Configuration issue
Power setting issue Check SectorEquipmentFunction:ConfiguredOutputPower & Eutrancelltdd:partOfSectorPower
Idle mode parameter issue Check Eutrancelltdd MO cell selection and reselection parameters & 3G&2G cell reselection parameter/feature
Operation issues Cell Barred Check Cell Barred , acBarring for different scenarios
Alarms
Common alarm : "resource configuration disable" , RRU fault , link failure , Check current & history alarms & take necessary action according to type of Alarm
Check RRU status , Reset boards , Verify SW on node
S1 links down due to faulty interface board.
VSWR CABX , verify VSWR on all ports of antenna
TMA check Faulty TMA Connections & faulty settings
Counter
Parameters
Action Plan
Legend
ACCESSABILITY-L14B
EGI-Network Engineering- LRAN