INITIAL LTE KPI TROUBLESHOOTING METRICS - NOKIA
ACCESSIBILITY
RETAINABILIT
RETAINABILITY
Y
MOBILITY
INTEGRIT
INTEGRITY
Y
PARAMET
PARAMETERS
ERS INFO
User data speed in Mbps
UE moves from one eNB to
target eNB while keeping its
connected state. LTE Services Possible Causes of
will be uninterrupted.
degradation:
Preparation – The Source
Source
LTE Downlink ThroughputeNodeB sends a request to the Cell Load(Users and PRB)
Target eNodeB, which
PDCCH Blocking & higher
Usage
The mechanisms dealing with performs admission control
1.RRC CONNECTION
successful Grant Bottleneck
RLF are implemented at both Execution – After successful
ESTABLISHMENT
preparation, the Source
Air Interface
UE and eNB side.
2.S1 SIGNALING
eNodeB sends a handover
Condition(RSSI,SINR,BLER)
1.If UE detects radio link
RTT/Retransmission
CONNECTION
problems it tries to r ecove
ecoverr command to the UE
Ul thp
ESTABLISHMENT
from RLF during specified
Mobility Issues
TM mode setting
3.INITIAL E-RAB
interval of time by RRC
RRC Connected Users
ESTABLISHMENT OR E-RAB connection re-e
re-establishment
stablishment 1-Preparation Phase
CQI Reporting Parameter
1.1- Wrong Tac Definition
ADDITION
procedure.
Scheduler Limitation
2.If eNB detects a radio link 1.2-X2-Link Failure
QOS Profile
RRC -Possible Causes of
problem it will wait until the 1.3-CAC Failure
Application server
1.4-Prep Timer Expiry
degradation
recovery (cancellation of
eNB Data build
1.5-Missing Neighbor
User or Control Plane and
RLF state), or release the
1.6-MME pool should be same RS Pwr boost
MME Overload ,Timer Expiry, UE.
1.7-Target cell is overloaded Others (VSWR,Backhaul
protocol Error,Lack of PUCCH The call drops can also be
Capacity)
Resources,Max no of RRC
initiated by the eNB (or MME) 1.8-Target cell Unavailable
Possible Causes of
1.9-Site Configuration issue
Connection Reached,RF
in other scenarios such as
degradation:
Quality Issues,cell availability timing alignment timer expiry, 2.0-Target cell has a fault
(alarm, disabled cell, etc.)
LTE Uplink Throughput
S1 Signalling -Possible
S1 reset etc.
Cell Load(Users and PRB)
Causes of degradation
Air Interface
2-Execution Phase
Transport issue,Wrongly
Retainability Issues
Condition(RSSI,SINR,BLER)
2.1-Failure
due
to
delay
HO
Configured TAC,Degraded due UE SIDERTT/Retransmission
2.2-Timer Expiry
to H/W Issue
1.T310 expiry
DL thp
2.3-RLF
ERAB -Possible Causes of
2.Maximum number of RLC
aPucchMinNumRrc:
Minimum allocated number of
UEs in the cell which m ay
establish a RRC connection.
degradation
Radio & Transport resources
not available,Radio connection
with UE lost,Failure radio
interface procedure,Mobility
retransmissions
3.Handover failure (T304
expiry)
4.Non-HO related random
access problem
Other Factor Impacting
Acc essi bil ity
RF Quality 1.Poor Coverage in DL and UL
impact the accessibility KPI
2.High UL RSSI can cause
degradation
3.Low SINR impact the KPI
4.Check whether the block
error rate (BLER) is
excessively high on the radio
interface.
Admission Control
Cell Availability
eNodeB SIDE1.PUSCH RLF
2.CQI RLF
3.HARQ RLF
4.PDCCH Order failure
5.Maximum RLC
Retransmissions Exceeded at
eNB
6.GTP-U failure at eNB
7.S1 reset
Scheduler Limitation
QOS Profile
Application server
eNB Data build
Others (VSWR,Backhaul
Capacity)
Power control Strategy
Proactive Scheduling
PUCCH and PRACH
Overheads
bandwidth
dlRsBoost- Transmission
dlRsBoostpower of the downlink
reference signals in a cell is
boosted (positive value)
respectively deboosted
(negative value) compared to
PDSCH
Baseband Pooling Admission
Failures
H/W issue (Re-set first) if
required replace RRU*
VSWR over threshold*
RANGE 1)
RANGE
2) & TM3(PDF
7.HIGH USAGE OF 64 QAM
AND 16 QAM SCHEME IN DL
8.Rank indicator (should be 2)
Parameter to Improve PRB
inactivityTimer - 30
p0NomPucch:
This parameter defines the cell
specific nominal power to be
used for PUCCH power
calculation in UE uplink power
control equation (P2), for
controlling mean received SNR
for control data.
Parameter to Improve
PDCCH:
actLdPdcch – 0
actOlLaPdcch – 1
enableAmcPdcch – 1
enablePcPdcch – 1
pdcchAggMsg4 – 8
pdcchAggPaging – 4
pdcchAggPreamb – 4
pdcchAggRaresp – 4
pdcchAggSib – 4
pdcchAlpha – 0.8
p0NomPusch:
This parameter defines the cell
specific nominal power for the
PUSCH. Used for P0_PUSCH
calculation in UE uplink power
control equation (P1) for
controlling the mean received
SNR for user data during
(re)transmission corresponding
to a received PDCCH with DCI
format 0 associated with a new
packet transmission.
Measure of the ability of a user
to obtain an E-RAB from the
system.
The Initial E-RAB
Establishment process can be
divided into the following
phases:
Measure of the ability of a user
to retain the E-RAB once
connected, for the desired
duration.Call
duration.
Call drops are also
referred as Radio Link
Failures (RLF)
(RLF)..
Poor coverage*
Alarms*
High Load (high traffic)*
2.4-ANR PCI Conflict (Collision
& Confusion)*
2.5-Target exceeds cell range
2.6-Target is a sleeping cell
2.7-Target has high uplink
interference
2.8-Poor RF conditions
2.9-Due to radio deaf radio
3-Other Causes
3.1-Poor Coverage
3.2-Interference
3.3-Wrong Parameters in
eNodeB
countdownPucchCompr
specifies the countdown timer
that defines how long it takes
before any new SIB
modification process may be
triggered again by a PUCCH
region compression.
rrcGuardTimer:
This timer is started when an
RRC message for setup,
modification or release of a
radio bearer is sent to the UE.
When the timer expires, the
corresponding procedure is
aborted
Power Parameters:
pMax-- maximum output power
pMax
of the cell
dlCellPwrRed - dlCellPwrRed
value 0dB only
supported,Improve cell edge
behaviour , reduce interference
and power consumption
dlChBw-Downlink
dlChBw -Downlink channel
tHalfRrcCon:
The minimal time period during
GOOD THROUGHPUT
which the internal state and the
1.RSSI- (< -105 DBM)
resources associated with an
2.SINR- Value >= 20
half-open RRC connection (i.e.
3.PRB UTILIZATION- (<80%) one for which no RRC
4.POWER RESTRICTED
Failure Counters :
connection setup complete
FAIL_INTRA_ENB_HO_PREP TRANSPORT BLOCK-UL - (< message has yet been
50%)
_AC
received) must not be deleted
FAIL_ENB_HO_PREP_OTH 5.CQI-(>10)
in the eNB.
FAIL_ENB_HO_PREP_TIME 6.MIMO RANK 2 TM2(PDF
FAIL_ENB_HO_PREP_AC
FAIL_ENB_HO_PREP_OTHE
R
INTER_X2_HO_PREP_FAIL_
Failure Counters for RRC:
QCI
SIGN_CONN_ESTAB_FAIL_O Faliure Counters:
ERAB_REL_ENB_RNL_UEL INTER_S1_HO_PREP_FAIL_
VLUP
SIGN_CONN_ESTAB_FAIL_C ERAB_REL_ENB_RNL_EUG TIME
INTER_S1_HO_PREP_FAIL_
P_POOL
R
SIGN_CONN_ESTAB_FAIL_O ERAB_REL_ENB_TNL_TRU NORR
VLMME
ERAB_REL_ENB_RNL_RRN INTER_S1_HO_PREP_FAIL_
OTHER
SIGN_CONN_ESTAB_FAIL_P A
INTER_S1_HO_PREP_FAIL_
UCCH
ERAB_REL_HO_FAIL_TIM
SIGN_CONN_ESTAB_FAIL_M EPC_EPS_BEARER_REL_RE QCI
AXRRC
Q_RNL
LTE_5590c E-UTRAN RRC
EPC_EPS_BEARER_REL_RE Parameter for HO
Improvement:
Connection Setup Rejection
Q_OTH
Ratio (%)
EPS_BEARER_SETUP_COM cellindividualoffsetEutran
hysteresisA3
LTE_5229e RRC Connection PLETIONS
Setup Failure Ratio due to
RRC_CON_RE_ESTAB_ATT_ timeToTriggerA3
a5ReportIntervalInterFreq"RRC timer expiry" failure (%) HO_FAIL
LTE_5230e RRC Connection RRC_CON_RE_ESTAB_ATT_ 240ms
a5TimeToTriggerInterFreqSetup Failure Ratio per Cause HO_OTHER
480ms
RRCCOMPL_ERROR
pdcchCqiShift – (-5)
pdcchHarqTargetBler – 1
No. of Establishment RRC
Connections per cell
(Connected Users)
RRC connected users,max
Avg_RRC_UE_Per_Cell
Parameters tuning for Call
Drop:
rrcGuardTimer - 3sec to
12sec
No. of Active UE’s per Cell
pdcchOrderConfig - 1 to 0
ENB_LOAD_ACT_UE_AVG
rlcProftPollRetr - 120ms to
ENB_LOAD_ACT_UE_MA
200ms
nCqiDtx - 100 or 250 to 0
Failure Counters for S1:
rlcProfmaxRetxThresh
rlcProfmaxRetxThres
h - t16 to
S1_SETUP_FAIL_IND_BY_M t32
ME
maxRetxThreshSrbUL - 16 to
S1_SETUP_FAIL_NO_RESP 32
offsetFreqInter-0dB
measQuantInterFreq-rsrp
Parameter to Improve
interPresAntP-true
Latency
hysThreshold3InterFreq-2
ilReacTimerUl – 0
threshold3InterFreq-60
cellSrPeriod – 2ms
threshold3aInterFreq-11
Parameter to Improve MIMO
a3OffsetRsrpInterFreq-15
dlMimoMode - 10
a3ReportIntervalRsrpInterFreq-mimoClCqiThD - 7
240ms
mimoClCqiThU - 8
a3TimeToTriggerRsrpInterFreq mimoClRiThD - 1.4
320ms
mimoClRiThU - 1.6
hysA3OffsetRsrpInterFreq-15 mimoOlCqiThD - 7
threshold3InterFreqQci1-60
mimoOlCqiThU - 8
Qrxlevmin:
Specifies the minimum
required RX RSRP level in the
cell.
T300:
Timer T300 supervises the
RRC connection establishment
procedure.
T301:
Timer T301 supervises the
RRC connection re-
establishment procedure.
mimoOlRiThD - 1.4
mimoOlRiThU - 1.6
Parameter to Improve
T310:
PUSCH:
Timer T310 supervises the
ulpcPuschConfig
recovery from physical layer
ulpcUpqualSch - 20
problems.
Handover Preparation :
ulpcPuschConfig
RRC Measurement Control
ulpcLowqualSch - 0
T311:
RLF Timer GUI Values:
(Source
ENB
->UE)
ulpcPuschConfig
Timer T311 supervises the
T300 - 1000ms
RRC
Measurement
Report
(UE
ulpcUplevSch
-88
RRC connection reT301 - 1500ms
-> Source ENB)
ulpcPuschConfig
establishment.
T310 - 2000ms
X2AP Handover Request
ulpcLowlevSch - -103
LTE_5
LTE_5750
750a
a Cell Availabili ty T311 - 5000ms
(Source ENB -> Target ENB) actUlpcMethod - 0
N310:
Ratio (%)
t304IntraLte - 2000ms
Uplink S1 Bearer
deltaTfEnabled - 0
This is the maximum number
t304InterRAT - 500ms
Establishment (SGW <->
p0NomPusch - -80
of consecutive "out of sync"
Parameters tuning for Call
N310 - n20
Target ENB)
ulpcAlpha - 7
indications received from lower
Failures:
N311 - n1
X2AP Handover Request
Parameter to Improve
layers.
aPucchMinNumRrc - 10 to 30
Acknowledge
(Target
ENB
->
PUCCH:
Uplink PUSCH DTX detection
countdownPucchCompr Source ENB)
dFpucchF1 - 1
N311: Maximum number of
and recovery
15min to 60min
X2 Bearer Establishment
dFpucchF1b - 0
consecutive "in-sync"
rlpDetEndNUl - 3(Mint)
tHalfRrcCon - 3000ms to
(Source ENB <-> Target ENB) dFpucchF2 - 1
indications received from lower
rlpDetMaxNUl - 1000(Mint)
6000ms
dFpucchF2a - 1
layers.
p0NomPucch: -120dBm to Handover Execution :
dFpucchF2b - 1
CQI DTX dete
detection
ction and
117dBm
1. RRC Connection
p0NomPucch - -116
nCqiDtx: The parameter
p0NomPusch: -106dBm to - recovery
Reconfiguration
Request
Parameter to Improve MCS: defines the number of
nCqiDtx - 0
102dBm
(Source ENB ->UE)
actModulationSchemeUL - 0 consecutive CQI DTX
nCqiRec - 2
Qrxlevmin: -120dBm to 2.
X2AP
SN
Transfer
Status
actUlLnkAdp - 5
detections causing radio link
114dBm
(Source ENB -> Target ENB) harqMaxTrDl - 5
failure indication.
Uplink Ack/Nack DTX
3. DL data flow during HO
iniMcsDl - 4
Detection
Features:
preparation (PGW -> UE)
iniMcsUl - 5
dlSrbCqiOffset: Provides the
rlpDetEndNoDl - 3(Mint)
actBbPooling - true (
4. UL data flow during HO
ulsSchedMethod - 0
CQI link adaptation offset
rlpDetMaxNoDl - 1000(Mint)
Baseband Pooling Feature )
preparation (UE -> PGW)
Parameter to Improve RF
applied to downlink
rlpDetMaxTimeDl - 0(Mint)
RRC Connections, GBR,
5. RACH Preamble (UE ->
Quality:
transmissions containing
Scheduled UEs/TT
UEs/TTII are
Target
ENB)
allowPbIndexZero
0
SRB1 messages.
UE Detected Radio Link
dynamically
dynamica
lly distributed
6.
Random
Access
Response
dlCellPwrRed
0
The more negative the value,
Failure initiates RRC
among cells depending on
(Target
ENB
->
UE)
dlPcfichBoost
0
the more conservative the
Connection Relive traffic load.
7. RRC Connection
dlPhichBoost
0
MCS and PDCCH aggregation
establishment:
Improved individual cell
Reconfiguration Complete (UE pMax level will be for the downlink
capacity (up to 76% more RRC Possible Failure Reasons
> Target ENB)
qrxlevmin - -130
SRB1 message transmissions.
resulting in Drop:
connections possible in a
8. Transmit transmission of
When the signaling shown is
single cell).
queued downlink data (Target Counters for troubleshoot:
a3Offset: low values not completed, the RRC rehandover earlier; high values AVG UL PRBs
establishment procedure fails ENB -> UE)
Sleeping Cells Detection :
9. DL data flow during HO
AVG DL PRBs
delay the handover.
The reasons for unsuccessful
Early detection” which will
execution (PGW -> UE)
PRB_USED_UL_TOTAL
trigger after 30mins of below RRC re-establishment can be
10. UL data flow during HO
PRB_USED_PUSCH
hysA3Offset: low values - pingassociated to, the transmission
event :
execution (UE -> PGW)
PRB_USED_PUCCH
pong
HO; High values - delay
of
RRC
REESTABLISHMENT
1.RRC connection setup failure
11. S1AP path switch Request PRB_USED_DL_TOTAL
the HO a& possible lead to lost
REJECT message from the
rate >= 1%
(Target ENB -> MME)
PRB_USED_PDSCH
connection to the serving cell.
eNB .
2.ERAB drop rate >=10%
12. Modify Bearer Request
DL_SCH_Kbits_per_PRB_use
Feature not activated
“Normal detection” which will
(MME -> PGW)
d
a3TimeToTrigger: low values Reception of another RRC
trigger after 30mins of no
13. Modify Bearer Response ( UL_SCH_Kbits_per_PRB_use ping-pong HO; High values activity on the cell due to below CONNECTION
PGW -> MME)
d
delay the HO a& possible lead
REESTABLISHMENT
procedure :
14. End Marker ( PGW ->
Grant
BottleNeck
to lost connection to the
REQUEST
1.RRC attempts
Target ENB)
Average
AGG
level
used
for
serving cell.
while
the
procedure
is
already
2.Throughput
15. Downlink data flow after
PDCCH
ongoing,
3.Successful RRC / bearer
handover (PGW->UE)
scheduling(LTE_1084a)(#)
tS1RelPrepL : Timer is
Unknown Reestab UE-Identity,
setup attempts
16. S1AP path switch Request Average Burst Initial Scheduler started when Source eNB
Loss of S1 or cell service,
4.PRBs used for DL or UL
Ack (MME -> Target ENB)
Delay
sends S1AP:Handover
CAC failure
transmission
17. . X2AP UE Context
PDCP_PDU_Delay_PerLstTTI required message to MME and
Release (Target ENB ->
_V1 (ms)
it is stopped when S1AP
Source ENB)
RSSI_PUSCH_AVG Handover Command or S1AP
Failure Counters for ERAB:
ERAB_INI_SETUP_FAIL_RNL
_RRNA
ERAB_INI_SETUP_FAIL_TNL
_TRU
ERAB_INI_SETUP_FAIL_RNL
_UEL
ERAB_INI_SETUP_FAIL_RNL
_RIP
Parameter to Improve ERAB:
rrcGuardTimer - 3sec to
12sec
dFpucchF1b - 0
dlSrbCqiOffset - -20 to -40
threshold3aInterFreqQci1-11
thresholdRsrpIFLBFilter--44
thresholdRsrpIFSBFilter--100
thresholdRsrqIFSBFilter--10
tS1RelPrepL - 2000 ms
SINR_PUSCH_AVG
RSSI_PUCCH_AVG SINR_PUCCH_AVG
Handover preparation failure.
INITIAL LTE KPI TROUBLESHOOTING METRICS - ERICSSON
ACCESSIBILITY
Measure of the ability of a
user to obtain an E-RAB
from the system.
The Initial E-RAB
Establishment process
can be divided into the
following phases:
RETAINABILIT
RETAINABILITY
Y
MOBILITY
INTEGRIT
INTEGRITY
Y
UE moves from one eNB to
User data speed in Mbps /
target eNB while keeping its
Throughtput in Bits per
connected state. LTE Services second.
will be uninterrupted.
C=B.LOG(1+S/N)
Preparation – The Source
Source
eNodeB sends a request to the GOOD THROUGHPUT
Target eNodeB, which
CONDITION
1.RSSI- (< -105 DBM)
The E-RAB Retainability QCI performs admission control
Execution – After successful 2.SINR- Value >= 20
drops per second and
1.RRC CONNECTION
3.PRB UTILIZATION- (<80%)
percentage KPIs represent the preparation, the Source
ESTABLISHMENT
eNodeB sends a handover
4.POWER RESTRICTED
number of abnormal active
2.S1 SIGNALING
command to the UE
TRANSPORT BLOCK-UL - (<
releases initiated by the
CONNECTION
50%)
EnodeB and the MME.
ESTABLISHMENT
Mobility Issues
5.CQI-(>10)
3.INITIAL E-RAB
Preparation Phase
6.MIMO RANK 2 TM2(PDF
Retainability Issues
ESTABLISHMENT OR E-RAB 1.OSS Alarm
MME pool should be same.
RANGE 1) & TM3(PDF
ADDITION
2.UL Interference
SpidHoWhiteList is active on RANGE 2)
7.HIGH USAGE OF 64 QAM
the target, which has
3.ERAB Abnormal release
AND 16 QAM SCHEME IN DL
primaryplmnReserved set to
Acc essi bil ity i ssu es
causes
8.Rank indicator (should be 2)
true.
4.UE Context Abnormal
Poor coverage
Target cell is overloaded (High
release causes
Alarms
Total Performance - Check all
capacity)
5.MME Abnormal release
High Load (High Traffic)
Target cell Unavailable : The important Accessibly, Mobility
H/W issue (Hard Reset on site 6.Mobility causes
and Retainability KPI
target cell is down / disabled
7.CTR and UETR analysis
/ RRU Replacement, if
TAC not defined on site, as per
8.Poor coverage*
required)
RRC Connected Users - Dl
9.High Load (high traffic)*
network design
High UL interference
License issue/Software issue. Throughput would reduce with
10.H/W issue (Re-set first) if
PCI conflict
Target cell has a fault (alarm, increase in number of
RACH Root Sequence Index required replace RRU*
disabled cell, etc.)
11.VSWR over threshold*
connected users.
plan need to be reviewed
Site Configuration issue.
UE camping in the wrong cell. Failure Counters:
Cell Reselection Parameters ENODEB INITIATED E-RAB
CQI ,64/16QAM,TM Modes
need to be tuned
Wrong System constant
setting(SC-556)
VSWR over threshold
Cell availability
Measure of the ability of a user
to retain the E-RAB once
connected, for the desired
duration.Call
duration.
Call drops are also
referred as Radio Link
Failures (RLF)
(RLF)..
RELEASE:pmErabRelNormalEnb
pmErabRelAbnormalEnbAct
MME INITIATED E-RAB
RELEASE:pmErabRelMme
pmErabRelMmeAct
Failures Counters for RRC:
pmRrcConnEstabFailLic
pmRrcConnEstabFailHighLoad 1.pmErabRelAbnormalEnbA
pmRrcConnEstabFailOverload ctCdt – The total number of
pmRrcConnEstabFailActiveUs abnormal ERAB releases by
erLicenseExceeded
the eNB per cell due cell down
pmRrcConnEstabFailFailureIn time (manual intervention)
RadioProcedure
Probable Solutions : - Check
pmRrcConnEstabFailBearerAd Outage report
missionRej
2.pmErabRelAbnormalEnbA
pmRrcConnReestFailLicMtRee ctHo – The total number of
st
abnormal ERAB releases per
pmRrcConnEstabFailLackOfR cell by the eNB due to
esources
handover execution failure
2-Execution Phase
ANR PCI Conflict (Collision &
Confusion)
Target exceeds cell range
Target is a sleeping cell
Target has high uplink
interference
Poor RF conditions
Parameters for im proving
Parameters
intra LTE HOSR:
cellindividualoffsetEutran
hysteresisA3
timeToTriggerA3
Parameter tuning for Inter
LTE HOSR:
a5Threshold1RSRP/-107
a5Threshold2RSRP/-115
hysteresisA5/10
pmRrcConnEstabFailUnspecifi Probable Solutions:- Check
timeToTriggerA5/480
ed
PCI Planning,Coverage
If MCPC enabled, then the
issue.Make EDT, Change
Counters for S1 fails:
following parame
parameters
ters are
Azimuth
pmS1SigConnEstabFail
High UL Interference issue on used:
a1a2SearchThresholdRsrp/Target cell
Counters for ERAB Setup
(PmRadiorecInterferencePwr). 103
fails:
hysteresisA1A2SearchRsrp/20
Check Connection b/w
pmErabEstabFailGbrDlEnb
Antenna Connector & RRU
pmErabEstabFailGbrUlEnb
Major reasons / causes behind
Connector.
pmErabEstabFailAddedLic
Also Repeater is responsible poor IRAT handover success
pmErabEstabFailInitLic
rate are as follows : sometimes for Hi-UL
Interference. Might be due to Coverage gap between LTE &
Troubleshooting for CFR:
3G/Other Technology.
Power Leakage.
High load – offload the traffic 3.pmErabRelAbnormalEnbA Improper parameter setting:
Implementation of Hi-Cap
ctUeLost – The total number a1a2SearchThresholdRsrp
Parameter (if Max RRC Conn of abnormal ERAB releases by from -110 dBm to -112 dBm
Users is more than
the eNB per cell due that the b2Threshold2RscpUtra from 115 dBm to -105 dBm
150/sector
150
/sector and
contact with the UE is lost
a2CriticalThresholdRsrp from pdcchutil>70% )
Probable Solutions:Solve the Poor Coverage issue 122 dBm to -124dBm
If still traffic load is m ore,
by changing tilt / azimuth
azimuth or
new site integration and
deployment
deployme
nt plan is
submitted
FORMULA
FORMULAS
S INFO
Initial E-RAB Establishment
Success Rate:
RRC Succ Rate =
(pmRrcConnEstabSucc/pmRrc
ConnEstabAttpmRrcConnEstabReAtt)*100
S1 Sign Succ Rate =
(pmS1SigConnEstabSucc/pm
S1SigConnEstabAtt)*100
Erab Estab Succ Rate =
(pmErabEstabSuccInit/
pmErabEstabAttInit)*100
E-RAB Drop =
((pmErabRelAbnormalEnbAct
+
pmErabRelAbnormalMmeAct)
/ (pmErabRelAbnormalEnb +
pmErabRelnormalEnb +
pmErabRelMme)) *100
HO Preparation Succ Rate =
((pmHoPrepSuccLteIntraF +
pmHoPrepSuccLteInterF) /
(pmHoPrepAttLteIntraF +
pmHoPrepAttLteInterF)) *100
HO Execution Suc c Rate =
Av CQI, % 64QAM sam ples
((pmHoExeSuccLteIntraF +
and RI indicates DL SINR
pmHoExeSuccLteInterF) /
status.. Average CQI should be (pmHoExeAttLteIntraF +
status
pmHoExeAttLteInterF)) *100
high (>10%), % of 64QAM
sample should be high (>10%),
DL Average UE
PRB(DL) And PDCCH
Throughput(Mbps) =
Utilization - High PRB and
(pmPdcpVolDlDrb –
pmPdcpVolDlDrbLastTTI +
PDCCH utilization would
pmPdcpVolDlDrbTransUm) /
impact the DL Throughput
pmUeThpTimeDl
DL Latency And RLC
Retransmission - High value UL Average UE
of DL latency(>9ms) and RLC Throughput(Mbps) =
pmPdcpVolUlDrb /
retransmission(> 1%) would
pmUeThpTimeUl
impact DL throughput.
Power Limited UE And No
Of A2 Events - High
occurrence of
Throughput Calcula
Calculation:
tion:
Lets’ assume we have 20 MHz
pmRadioTbsPwrRestricted and channel bandwidth.
we need to calculate the
pmBadCovEvalReport
resource elements in a
indicates poor DL coverage.
subframe for this band i.e.
12subcarriers x 7 OFDMA
Alarm & Parameter/ Feature
symbols x 100 resource blocks
Check
x 2 slots= 16800 REs per
RSSI - High uplink RSSI would subframe.
Assume we have 64 QAM
impact the throughput.
modulation and no coding, one
% of 16 QAM samples - Low modulation symbol will carry 6
usage of 16 QAM modulations bits.
16800 modulation symbols x 6
scheme in UL would impact
bits / modulation symbol =
the UL throughput
100800 bits.
So, the data rate is 100800 bits
PUCCH & PUSCH SINR / 1 ms = 100.8 Mbps.
Poor UL SINR conditions
would impact UL throughput. With 4×4 MIMO, the peak data
rate goes up to 100.8 Mbps x 4
= 403 Mbps.
Power limited UE - High
Estimate about 25% overhead
number of power limited UE
indicates poor uplink coverage. e.g. PDCCH, reference signal,
sync signals, PBCH, and some
We get 403 Mbps x 0.75 = 302
Mbps.
appropriate parameter value
BLER (bad coverage)
Failure Counters:
setting
Downlink Interference (Bad
THROUGHPUT
License Counters
E.g. : - partOfSectorPower,
CQI)
dlMaxRetxTh of SRB1
TROUBLESHOOTING:
ENB Power, P0NominalPucch pmHoPrepRejInLicConnUsers MIMO Parameters
ULMaxRetxTh of SRB1
Scheduling algorithm
pZeroNominalPucch:
pZe
roNominalPucch: From - / P0NominalPusch (for uplink pmHoPrepRejInLicMob
Check whether the block error
pmHoPrepRejInLicRlcUm
Coverage).
Low Demand
120 to -117
rate (BLER) is excessively high
pZeroNominalPusch:
pZeroNominalP
usch: From - High UL NI Issue(As per earlier pmHoPrepRejInLicMultiErab CQI reporting frequency
on the radio interface.
interface. If the
mentioned. Also make sure
Other (VSWR, Backhaul
106 to -102
BLER is higher than 10%, the
Nominal power Should not set Coverage Evaluation
capacity)
qRxLevMin : from -120 to channel condition is poor and
Counters
very high otherwise it will
114
will result in low throughput.
create
interference
in
pmBestCellEvalReport
Counters for troubleshoot
MCPC feature need to enable
Check whether uplink
neighbour
cell).
pmBadCovEvalReport
pmRrcConnMax
for poor covera
coverage
ge
interference exists, in a normal
4.pmErabRelAbnormalEnbLi
pmHoOscIntraF
pmPrbUtilDl
/
pmPrbUtilUl
connected users license
case, the UL RSSI on each
pmHoOscInterF
c – The total number of
pmBadCovEvalReport
Change from 100
1000
0 to 200
2000
0
pmMeasMissingNeighRel
pmRadioRecInterferencePwrP resource block (RB) is about (
abnormal E-RAB Releases
to 120} ) dBm when the
the
initiated by the RBS due to
UCCH/pmRadioRecInterferenc – {119 to
The following KPIs need to
cell is unloaded. If the RSSI is
IRAT MCPC FEATURE:
ePwr
be closely monitored, once license reject (per cell).
3 dBm to 5 dBm higher than
the required changes for HI 5.pmErabRelAbnormalEnbA featureStateStateMobCtrlAtP pmsinrpucchdistr &
the normal value (when unctTnFail
–
The
total
number
of
oorCov
provides
information
pmsinrpuschdistr
CAP Settings are
loaded), uplink interference
abnormal
ERAB
releases
per
about
the
licensed
feature
–
pmRlcArqUlack /
implemented:
exists. Locate the interference
cell
due
to
S1
interface
down,
Mobility
Control
At
Poor
pmRlcArqUlNack
RACH Success Rate.
source, and mitigate the
"X2
interface
down"
or
Coverage.
The
feature
needs
pmSchedActivityCellDl
Accessibility and Retainability.
interference (Could be some
"Transport
Resource
to
be
set
to
1.
/pmSchedActivityUeDl
Max and Average RRC
external interferer or values of
Unavailable
pmRadioTxRankDistr
Connected UEs.
Probable Solutions : - Issue
serviceStateStateMobCtrlAtP pmRadioTbsPwrRestricted/pm pZeroNominalPusch in
High/Over load.
neighbour cells are too high)
can
be
resolved
with
the
help
oorCov - Indicates the
RadioTbsPwrunRestricted
Handover performance.
of
NOC
/
IM
Team
by
raising
licensed
feature
Mobility
pmMacHarqDlAck16qam/64qa Check whether the eNodeB’s
UL/DL Throughput.
parameter settings are correct.
the
required
tickets.
Control
At
Poor
Coverage.
The
m/Qpsk
CCE utilization.
6.pmErabRelAbnormalEnbA feature needs to be set to 1.
pmMacHarqDlNack16qam/64q If the values are inconsistent,
confirm whether the settings
ctHpr – The total number of
am/Qpsk
HI-CAP Parameters:
are customized for the operator
mobCtrlAtPoorCovActive
abnormal
ERAB
releases
by
pmMacHarqUlFail16qam/Qpsk
ulMaxRetxThreshold - set to
the eNB per cell due to
Specifies if the feature Mobility pmMacHarqUlSucc16qam/Qps or have been changed to
8 (reduces the number of
incorrect values
Control at Poor Coverage is
k
uplink RLC retransmissions for handover preparation
Check whether the number of
Probable
Solutions:enabled or disabled in the cell.
signaling radio bearer and data
users in the cell is excessively
radio bearer)
The
parameter needs to be set Para
Parameters
meters for throughput
MME
missing
issue or MME
large. If an excessively
excessively large
might
be
disabled.
to
TRUE.
improvement:
tPollRetransmitDl - set to 160
number of users have
Transport
issue
suspected.
ms (It extends the downlink
accessed the cell and ENodeB
License issue suspected.
a1a2SearchThresholdRsrp - dlMaxRetxThreshold
time for new poll if no status
are exhausted when a UE
Site
Configuration
issue.
The
Reference
Signal
(DRB/SRB)
8/8
–
Reduce
the
report is received for both
Received Power (RSRP)
no. of RLC retransmission for accesses the cell, the user
signaling radio bearer and data
throughput will be low.
DL/UL MAXRETXTHDRB:
threshold value for events
SRB/DRB in DL.
radio bearer )
Check whether relative license
dl maxRetxthdrb from 8 to 32 A1Search and A2Search. For
tPollRetransmitUl - set to
information is incorrect and if
ul
maxRetxthdrb
from
8
to
32
single-carrier
sites,
ulMaxRetxThreshold
160ms (It extends the uplink
a1a2SearchThresholdRsrp
(DRB/SRB) - 8/8 - Reduce the the license has not expired
time for new poll if no status
tinactivity
timer
value
is
replaces
a2ThresholdRsrpPrim
no. of RLC retransmission for Check whether the traffic
report is received for both
volume to the eNodeB is
parameter.
It
needs
to
be
set
to
changed
from
61s
to
20s
SRB/DRB in UL.
Signaling Radio Bearer and
insufficient. A common reason
-116
for
intraLTE,
-112
for
Data Radio Bearer. The
for the insufficient input traffic
interRAT_10
and
-110
a3offset
:
Change
from
3
to
2
tPollRetransmitDl
changes will reduce SE/TTI
volume is a bottleneck
interRAT_5.
(DRB/SRB) –
usage for retransmissions, and dB
transmission bandwidth at an
a2TresholdRsrpPrim :
160msec/1600msec.
allow more SE/TTI to serve
intermediate node.
a2CriticalThresholdRsrp
Change from -120 to -110
traffic)
The
Reference
Signal
dBm.
noOfPucchsrUsers – 590 deltaPsdRs2Tx - (3dB) to
RBS Parameter Settings
Received Power (RSRP)
Max no. of PUCCH users is
(0dB) (RS power boost is
EUtranCellFDD
threshold
value
for
event
a3Offset
=
3
dB,
hysteresis
=
used
reduced for inter-site/cell
dlChannelBandwidth /
A2Critical.
The
interference under low Inter
dlChannelBandwidth
a2CriticalThresholdRsrp
performed
once
Neighbor
Cell
–
320
noOfPucchCqiUsers
Site Distance (ISD) RF radio
(nrOfSymbolsPdcch) (Control
parameter replaces
RSRP > 4dB of Serving Cell
Max no. of PUCCH users is
environment)
Region Size)
a2ThresholdRsrpSec. The
used
numInitialAccessAndIncomi RSRP
setting
for
A3
setting,
A3
event
handover
ngHo - is changed from a
controls whether OLSM MIMO
a2CriticalThresholdRsrp is deltaPsdRs2Tx – 0dB –
Global 10 to Local 10 or 20 (It will be performed when
is used (2) or not.
122
for
all
sites.
neighbor
cell
is
greater
than
Change RS Power boost to
reduces the maximum number
a3Offset
+
hysteresis
(RSRP)
reduce DL inference and
of initial accesses and
this is the % part of RU
timeToTriggerA2Critical shrink coverage.
incoming handovers that are of the current serving cell.
capability independent of
The
time-to-trigger
value
for
allowed during a time window
measurement in event
If retransmission limit
PdcchLaGinrMargin – 3dB – SectorEquipmentFunction::con
without triggering the load
A2Critical. This parameter is Reduce PDCCH link adaption fOutputPower settings
increases from 8 to 32, RL
control mechanism )
set
to 1280ms for all sites.
failure
due
to
retransmission
algorithm from 10db to 3 db.
pdcchLaGinrMargin - set to
UEs need this to be increased
limit
reached:
30 (3dB) (This reduces
timeToTriggerB2
The
time
SRB:
360ms
(8)
to
1440ms
144
0ms
QciProfilePredefined.schedu or ACK/NACKs are not
PDCCH link adaption
received successfully on
to
trigger
value
for
the
eventB2
(32)
lingAlgorithm – Favor user
algorithm from 10db to 3 db .
PUCCH.
measurement.
Set
to
1280ms
DRB:
400ms
(8)
to
1600ms
160
0ms
with better CQI in order to
3dB is a reasonable
for
all
sites.
(32)
increase
the
utilization
of
less
compromise between saving
UEs need this to be increased
robust MCS Values.
CCE resources and ensuring
from default or lots of errors
Retainability issue due to HO
reception of PDCCH by the
seen on PUSCH
failure:
UL THROUGHPUT
UE)
Need to tune
cellindividualoffset
pzeronominalpucch (-120dBm
to -117dBm)
pzeronominalpusch (-102dBm
to -98dBm)