LTE KPI-Retainability.pdf

RETAINABILITY-L14B

UE Lost

pmErabRelAbnormalEnbActUeLos (UE unreachable)

Radio Cause

Poor DL SINR (CQI)

Tune related parameters (as mentioned beside) , Audit cell reselection parameters Physical optimization (Tilt , Azimuth , height of antenna) , also Identify overshooting cells causing interference in DL

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..)

pZeroNominalPucch pZeroNominalPusch

Check HW issues , alarms , improper cabling , connector issues , DUS Board error

PCI confliction or confusion

Audit PCI of near by sites , also check if there is overshooting cell creating conflict maximumTransmissionPower partOfSectorPower confOutputPower crsGain pdschTypeBGain

pmBadCovEvalReport pmRadioTbsPwrRestricted pmBadCovSearchEvalReport

Coverage issues

Poor DL SINR (CQI)

UL RSSI

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) Check if there is scope of new site

maximumTransmissionPower partOfSectorPower confOutputPower crsGain pdschTypeBGain

pmRadioUeRepCqiDistr , pmRadioUeRepCqiDistr2

pmRadioRecInterferencePwr pmRadioRecInterferencePwrPucch pmRadioRecInterferencePwrPrb1~100 pmSinrPucchDistr , pmSinrPuschDistr

UL RSSI HW and other causes

maximumTransmissionPower partOfSectorPower confOutputPower crsGain pdschTypeBGain

pmBadCovEvalReport pmRadioTbsPwrRestricted pmBadCovSearchEvalReport

Coverage issues

maximumTransmissionPower partOfSectorPower confOutputPower crsGain pdschTypeBGain

pmRadioUeRepCqiDistr , pmRadioUeRepCqiDistr2

pmRadioRecInterferencePwr pmRadioRecInterferencePwrPucch pmRadioRecInterferencePwrPrb1~100 pmSinrPucchDistr , pmSinrPuschDistr Alarms

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) Check if there is scope of new site

pZeroNominalPucch pZeroNominalPusch

Tune related parameters (as mentioned beside) , Audit cell reselection parameters Physical optimization (Tilt , Azimuth , height of antenna) also Identify overshooting cells causing interference in DL

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..)

Alarm need to monitor , some alarms need to monitor are VswrOverThreshold , Serviceunavailable (S1 connection failure) , Gigabit Ethernet Link Faul Configuration issues

pmErabRelAbnormalEnbActHo (handover execution failure)

pmCellDowntimeAuto pmCellDownLockAuto

Cell Down Auto Cell down

eNodeB Cause

Baseband Startup issue Transport Cause EPC Cause

pmCellDowntimeMan pmCellDownLockMan

Cell Down Manually

HW issues & Alarms

Availability Sleeping Cell

pmRaAttCbra pmRaSuccCbra pmRaFailCbraMsg2Disc pmRaAttCfra pmRaSuccCfra pmRaFailCfraMsg2Disc pmRaAllocCfra pmRrcConnEstabAtt pmRrcConnSucc

eNodeB Initiated

LTE KPI

Retainability

pmHoPrepRejInLicMob

License issue:

pmHoPrepRejInLicRlcUm

Legend:

Admission reject

Counters

Check SectorEquipmentFunction:ConfiguredOutputPower & Eutrancelltdd:partOfSectorPower

Idle mode parameter issue

Cell Barred

Check Eutrancelltdd MO cell selection and reselection parameters & 3G&2G cell reselection parameter/feature

Check Cell Barred , acBarring for different scenarios

Check "licenseCapacityConnectedUsers" of Target cell Also Graceperiod should be noticed to exceed the licensed capacity limits for a limited periodof timeOffload traffic from target cel

Audit licenseState,featurestate,servicestate & other paramter related to MultiErabsPerUser feature

Audit licenseState,featurestate,servicestate & other paramter related to RlcUm feature

pmHoPrepRejInBearerAdmissionRej

Configuration issue

Parameter

Power setting issue

capacityUnitConnectedUsers gracePeriodTimeLeft

Check these counters on target cell , Reduce no. of HO by physical opti or features (UE Level Oscillating Handover Minimization & Automated Mobility Optimization) MP capacity of DUS is higher than DUL , to increase MP capacity DUL can be replaced by DUS Physical changes (Tilt , Azimuth , height of antenna) to offload traffic from target cell Offload Target cell Load by changing Layering strategy, Idle mode cellreselection, connected mode mobility & Load balancing parameters

pmHoPrepRejInHighLoad (MP load control) pmHoPrepRejInOverload (procedure latency supervision)

Load:

Operation Cause

Audit licenseState,featurestate,servicestate & other paramter related to Intra freq & Inter freq HO feature

pmHoPrepRejInLicMultiErab

SARR(Session Abnormal Release Rate)

dlTransNwBandwidth , ulTransNwBandwidth zzzTemp20 , zzzTemp21 , pmRrcConnMax , pmRrcConnLevSum

Configuration issues

Cell Down Auto Cell down

pmErabRelAbnormalEnbActHpr (handover preparation failure)

pmCellDowntimeAuto pmCellDownLockAuto

Availability Sleeping Cell

pmCellDowntimeMan pmCellDownLockMan

pmRaAttCbra pmRaSuccCbra pmRaFailCbraMsg2Disc pmRaAttCfra pmRaSuccCfra pmRaFailCfraMsg2Disc pmRaAllocCfra pmRrcConnEstabAtt pmRrcConnSucc

Target cell

eNodeB Issue

Inter freq LTE

pmErabRelMmeActUnspecified

pmErabRelMmeActUserInactivity

Cell Barred

Check Eutrancelltdd MO cell selection and reselection parameters & 3G&2G cell reselection parameter/feature

Check Cell Barred , acBarring for different scenarios

If MME pool is different at source and target then HO-Preparation fail will be 100%, command "get . termpointmme" can be used to find out the MME pool IP Target cell is prelaunch cell.(Primaryplmnreserved)

a5Threshold1RSRP ; a5Threshold2RSRP ; hysteresisA5 ; timeToTriggerA5 , a2TresholdRsrpPrim , ANR parameters a1a2SearchThresholdRsrp ; hysteresisA1A2SearchRsrp ; timeToTriggerA2Search ; a2CriticalThresholdRsrp ; hysteresisA2CriticalRsrp ; timeToTriggerA2Critical

Check HW issues , alarms , improper cabling , connector issues , DUS Board error

Features

pmErabRelMme , pmErabRelMmeArp pmErabRelMmeAct , pmErabRelMmeHo pmErabRelMmeActHo , pmErabRelAbnormalMmeAct pmErabRelAbnormalMMeActQci , pmErabRelAbnormalMMeActArp pmErabRelMmeQci

Check SectorEquipmentFunction:ConfiguredOutputPower & Eutrancelltdd:partOfSectorPower

Idle mode parameter issue

S1 or X2 interfaces DOWN (Transport Resource Unavailable) , Also check 3G collocated nodeb in term of SCTP LOSS

Parameters

MME Initiated

Power setting issue

Check any planned activities , Check high temperature on DU,RU bord also Check eNodeb alarm logs , also it may be do to common transport network

Other important parameters/features

pmErabRelMmeActEutra (Release due to Eutran generated reason)

Operation Cause

manually locked during network configuration issues ((eg. adding/changing/removing hardware) manually locked during parameter change (eg. activate feature)

a2TresholdRsrpPrim ; hysteresisA2Prim ; timeToTriggerA2Prim ; b2Threshold1Rsrp ; b2Threshold2RscpUtra ; hysteresisB2 ; timeToTriggerB2

pmErabRelAbnormalEnbActTnFail

HW and other causes

check for alarms like Service Unavailable(S1 connection failure)

check for alarms like Service Unavailable(S1 connection failure) , Ip packet loss "above" SGW

cellIndividualOffsetEUtran ; a3offset ; hysteresisA3 ; timeToTriggerA3

MCPC feature para pmErabRelAbnormalEnbActCd

Baseband Trace can be used , te enable all bbmcBbOmMeSwU

pmErabRelAbnormalEnbActTnFail

Check related alarms like Serviceunavailable (S1 connection failure,Hardware failure,GeneralHwError,GeneralSwError,Gigabit Ethernet Link Fault

MME pool

IRAT

S1 issues

trace from MSG1 to MSG5 , verify symtoms for sleeping cells

Configuration issue Operation issues

Alarms

ensure proper configuration , especially for all new site which are integrated recently

Ensure the eNodeB structure of the restart, MP、Baseband or RRU lh all llog -l (do complete eNB health checkup)

Verify symtoms for sleeping cell

Catch Trace(Baseband) Non-access issue

Auto Restart

Baseband Startup issue EPC Cause

Other checks

Transport nw Issue

eNodeB Cause

Transport Cause

Cell Down Manually

Tune HO related parameters

Audit UE Admission Control,Bearers (SRB & DRB) Admission Control,Transport Network Admission Control & Emergency call prioritization Physical changes (Tilt , Azimuth , height of antenna) to offload traffic from target cell

Check configuration issues (especially after new site is integrated) (check MO ExternalEUtranCellTDD,EUtranCellRelation,TermPointToENB,TermPointToMme) (also check config para ex. Activeplmnlist,PCI , TAC , EutranFrequencyRef , IP address of TermPointToENB & MME)

Action plan

Intra LTE

check for alarms like Service Unavailable(S1 connection failure)

manually locked during network configuration issues ((eg. adding/changing/removing hardware) manually locked during parameter change (eg. activate feature)

Check HW issues , alarms , improper cabling , connector issues , DUS Board error

pmHoPrepRejInLicConnUsers

Handover Failure

Baseband Trace can be used , te enable all bbmcBbOmMeSwU

pmErabRelAbnormalEnbActTnFail

trace from MSG1 to MSG5 , verify symtoms for sleeping cells

Configuration issue Operation issues

HW issues

S1 issues

check for alarms like Service Unavailable(S1 connection failure) , Ip packet loss "above" SGW

Verify symtoms for sleeping cell

Catch Trace(Baseband) Non-access issue

pmErabRelAbnormalEnb , pmErabRelAbnormalEnbQci pmErabRelAbnormalEnbArp , pmErabRelNormalEnb pmErabRelNormalEnbQci ,pmErabRelNormalEnbArp mErabRelNormalEnbUserInactivity , pmErabRelNormalEnbAct pmErabRelNormalEnbActArp , pmErabRelNormalEnbActQci pmErabRelAbnormalEnbAct , pmErabRelNormalEnbUserInactivityQci

ensure proper configuration , especially for all new site which are integrated recently

Ensure the eNodeB structure of the restart, MP、Baseband or RRU lh all llog -l (do complete eNB health checkup)

Auto Restart

RLC layer retransmissions

dlMaxRetxThreshold ulMaxRetxThreshold

Multi-Target RRC Connection Re-Establishment Mobility Control at Poor Coverage

If MME related issue is their many sites in the NW will be impacted & if Core related issues is there all sectors of site will be impacted. If issue is in single sector then mostly it will be case of HW or radio related issues, Check HW issues , alarms , improper cabling , connector issues Check Radio Condition (low coverage , UL_Pathloss, NOISE_PUSCH/PUCCH) (refer radio cases above) also Check Traffic Volume , also check if there is sudden spike in traffic) Check if multi target RRC connection reestablishment feature is functioning properly.

Check is required on both Radio & core side If MME related issue is their many sites in the NW will be impacted & if Core related issues is there all sectors of site will be impacted. If issue is in single sector then mostly it will be case of HW or radio related issues (check following) , Check HW issues , alarms , improper cabling , connector issues Check Radio Condition (low coverage , UL_Pathloss, NOISE_PUSCH/PUCCH) (refer radio cases above) also Check Traffic Volume , also check if there is sudden spike in traffic) If there is no issue on eNB side , core team should troubleshoot the issue , Traces at core side can help to do RCA Release due to long UE inactivity

EGI-Network Engineering- LRAN