5G Performance
Optimisation
ADVANCE YOUR CAREER WITH 5G
5G Performance Optimisation
5G performance Optimisation
●
Performance prerequisites are highly dependent on traffic scenarios.
●
The concentration is on giving out high data rates and high capacity
in an indoor hotspot conditions.
5G KPI
●
Accessibility
●
Retainability
●
Latency
●
Mobility
●
Throughput
Accessibility KPI
●
It is the probability that the user of a service after a request will be able
to access the network or not.
Accessibility KPI
NR Cell - total number of preambles
● Default value : 64
●
Recommended value : 16
●
Other recommended value : 32
●
Environment / scenario : “Dense urban” , “Small cell”.
Accessibility KPI
●
Description : For small cell deployment (short preambles format) it
may be useful to reduce maximum number of preambles per cell.
●
Too low number of preambles per cell may cause too much collisions
under heavy load.
Accessibility KPI
NR Cell : PRACH Configuration
● Default value : 38
●
Recommended value : 151
●
Other recommended values : 156,157,158,159,160
●
Environment/scenario : general
Accessibility KPI
●
Description : It is applicable for TDD FR1.
●
Given PRACH indicates give average capacity for PRACH with B4
preamble format that on SCS 30kHz (FR1) provides at maximum
around 1.9km cell range.
Accessibility KPI
NR Cell : initial Preamble Received Target Power
● Default value : -104
●
Recommended value : -104
●
Description : Initial Preamble Received Target Power default value is
-104 is recommended for FR1. Recommended value for FR2 is -116.
●
If NRCELL NRAFCN is lower or equal to 800 000 then elevated frequency
range is FR1 i.e below GHz.
Accessibility KPI
NRCELL.actBeamforming
● Default value : 0
●
Recommended value : 1
Accessibility KPI
NRCELL.beamset.basicBeamSet
● Default value : 1
●
Recommended value : 7
●
Description : beamset_6_2 is providing best averaged throughput in
drive tests, beamset_6 and beamset_5_3 are also providing good
performance.
Accessibility KPI
NRCELLGRP.number of Transmitted SS Blocks
● Default value : 1
●
Recommended value : 2
●
Description : to align with basic Beam Set equal to 2
Accessibility KPI
NRCELL.cbraPreamblesPerssb
● Default value : 64
●
Recommended value : 56
●
Description : value n56 permits to activate contention free RACH
during handover, which leads to better handover success rate.
Accessibility KPI
NRCELL.zeroCorrelationZeroConfig
● Default value : 13
●
Recommended value : 14
●
Description : if expected cell size is larger than 871 m in cmW and
larger than 218 m in mmW.
Accessibility KPI
NRCELL.zeroCorrelationZeroConfig
● Default value : 13
●
Recommended value : 14
●
Description : if expected cell size is larger than 871 m in cmW and
larger than 218 m in mmW.
Accessibility KPI
NRCELL.initialPreambleReceivedTargetPower
● Default value : -104
●
Recommended value : -96
5G Accessibility Parameters
Accessibility Parameters
●
Maximum number of RRC connected users in a NR Cell Group for SA :
250.
●
Additional number of non-GBR capacity for handivers : 0
●
Offset to the signaled q-RxLevMin
●
Maximum number of users in a NR cell for NSA operation : 250
●
Maximum number of non-GBR data radio bearers in a NR cell Group
for SA : 500
Accessibility Parameters
●
Number of transmitted Synchronization Signal Blocks : 1
●
Maximum number of Preamble transmission : 6
●
Maximum number of secondary cells for DL carrier Aggregation : 3
●
Zero correlation zone config : 13
●
Maximum number of UEs scheduled in DL TD scheduler : 2
Accessibility Parameters
●
CBRA preamble per SSB : 64
●
Maximum number of users in a NR cell group for NSA operation : 500
●
Basic Beam set : 1
●
CBRA preambles per SSB : 64
●
PRACH root sequence index : 0
Accessibility Parameters
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Number of SSB per RACH occasion : 3
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PDSCH power back-off for 256 QAM : 15
●
Power Ramping Step High Priority CFRA : 2
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Maximum number of users Per CPCL instance : 50000
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Maximum number of users in a NR cell for NSA operation : 250
Accessibility Parameters
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Maximum number of secondary cells for UL carrier aggregation : 1
●
Timer for contention resolution : 7
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Probability false alarm target for PRACH : 3
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PRACH frequency start : 0
5G KPI
●
5G UL CA activated to configured SCell ratio
●
5G Status transfer failure ratio during SgNB addition
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5G contention free RACH setup attempts
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5G Radio Admission success ratio for NSA user
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5G Non Standalone call accessibility, 5G side
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5G Average number of NSA users
5G KPI
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5G contention based RACH setup success ratio.
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5G Downlink CA reconfiguration success ratio
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5G DL CA reconfiguration attempts
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5G DL CA activated to configured SCell ratio
●
5G contention free RACH setup success rate
●
5G number of radio transmission requests for NSA user
5G KPI
●
5G UL CA aggregation reconfiguration success ratio
5G Mobility KPI
5G Mobility KPI
●
This KPI is used to measure the performance of network which can
handle the movement of users and can still retain the service for the
user such as handover etc.
5G Mobility KPI
NRCELL.a3MeasEnabled
● Default value : 0
●
Recommended value : 1
5G Mobility KPI
NRCELL.a3MeasSsbRsrp.a3HysteresisSsbRsrp
● Recommended value : 4
●
Description : 2dB is better to avoid ping pong handover
5G Mobility KPI
NRCELL.cbraPreamblesPerSsb
● Default value : 64
●
Recommended value : 56
●
Description : value n56 permits to activate contention free RACH
during handover, which leads to better handover success rate.
5G Mobility KPI
NRBTS.actDataDuplicationForMobility
● Default value : 0
●
Recommended value : 1
5G Mobility KPI
NRCELL.a3MeasSsbRsrp.a3TimetoTriggerSsbRsrp
● Recommended value : 1
●
Description : 320 ms is better to avoid ping pong handover
5G Mobility KPI
NRBTS.actIntraFreqInterGnbMobilityNSA3x
● Default value : 0
●
Recommended value : 1
●
Description : inter-gNB mobility can be activated to improve mobility
and retainability KPI’s
5G Mobility KPI
NRBTS.a3MeasSsbRsrp.a3OffsetSsbRsrp
●
Recommended value : 8
●
Description : 4dB A3 offset is better to avoid ping pong handover
5G Mobility KPI
NRBTS.a3MeasSsbRsrp.a3OffsetSsbRsrp
●
Recommended value : 8
●
Description : 4dB A3 offset is better to avoid ping pong handover
5G Mobility Parameters
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CBRA Preambles per SSB : 64
●
A5 Hysteresis Ssb Rsrq
●
A3 Measurement Configuration Enabled : 0
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A5 time to trigger Ssb Rsrq
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s-Measure Configuration Ssb Rsrp
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Cell individual SSB RSRQ offset of related neighbor cell : 24
5G Mobility Parameters
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A3 Offset Ssb Rsrq
●
A5 Threshold2 Ssb Rsrq
●
A3 Hysteresis Ssb Rsrp
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CBRS parameters per SSB : 64
●
A3 offset SSB Rsrq
●
A5 Measurement Configuration enabled : 0
5G Mobility Parameters
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A3 offset ssb rsrq
●
A5 measurement configuration enabled : 0
●
A3 offset ssb rsrp
●
Filter coefficient Ssb rsrq : 4
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A5 threshold1 Ssb Rsrq
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Cell individual SSB RSRP offset : 24
5G Mobility Parameters
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A3 time to trigger Ssb Rsrp
●
A5 threshold2 Ssb Rsrp
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Active data duplication for SA mobility
●
A3 hysteresis Ssb rsrp
●
Additional number of user capacity for handovers
●
A3 measurement configuration enabled
5G Mobility Parameters
●
A3 measurement Configuration enabled
●
Activate intra MeNB mobility : 0
●
Filter coefficient Ssb Rsrp : 4
●
A5 measurement configuration enabled : 0
●
Cell individual SSB RSRP offset of related neighbor cell : 24
●
A5 time to Trigger Ssb Rsrp
5G Mobility Parameters
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Activate intra-frequency intra-gNB mobility NSA : 0
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Activate data duplication for mobility
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Cell individual SSB RSRQ offset
●
Activate intra-frequency inter-gNB mobility NSA 3x
●
Additional number of non-GBR capacity for handovers
Mobility KPI’s
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5G Average duration of executed intra-gNB intra frequency PSCell
changes.
●
5G Intra gNB intra frequency PSCell change preparation attempts.
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5G Intra gNB intra frequency PSCell change total failure ratio.
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5G Intra gNB intra frequency PScell change preparation success ratio.
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5G Intra gNB intra frequency PScell change total success ratio.
5G Retainability KPI
5G Retainability KPI
●
This KPI is used to measure how the network keep user’s possession or
able to hold and provide the services for the users
5G Retainability Recommendations
NRBTS.tRLFindForDU
● Default value : 0
●
Recommended value : 8
●
Description : to avoid too sensitive RLF detection.
5G Retainability Recommendations
NRBTS.drbRlcAmDefProf.dlMaxRetxThreshold
● Default value : 16
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Recommended value : 32
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Description : to avoid too sensitive RLC max retransmission
5G Retainability Recommendations
NRBTS.rlcProf4.maxRetxThreshold
● Default value : 6
●
Recommended value : 7
5G Retainability Recommendations
NRBTS.rlcProf4.maxRetxThreshold
● Default value : 6
●
Recommended value : 32
5G Retainability Recommendations
NRBTS.drbRlcAmDefProf.ulMaxRetxThreshold
● Default value : 16
●
Recommended value : 32
●
Description : to avoid too sensitive RLC max retransmission
Retainability Parameters
●
Maximum retransmission threshold UL : 4
●
Maximum retransmission threshold : 6
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Maximum retransmission threshold DL : 4
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Non StandAlone inactivity timer : 10
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Activate UE initiated RLF : 1
●
RLF indication timer for DU : 0
Retainability Parameters
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F1AP UE Proc Guard Timer : 2500
●
Activate inactivity detection for NSA UE : 0
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Activate gNB initiated RLF : 1
5G Retainability KPI
●
5G SgNB triggered normal release ratio
●
5G total number of releases on SGNB side
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5G number of UE releases due to radio link failure
●
5G number of MeNB initiated SgNB releases
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5G SgNB release success ratio due to user inactivity
5G Retainability KPI
●
5G Number of UE radio link failures
●
5G number of SgNB initiated releases due to user inactivity.
5G Throughput KPI
5G Throughput KPI
●
This KPI is used to measure total throughput.
5G Throughput Recommendations
NRCELL.ullaDeltaSinr/Min
● Default value : -300
●
Recommended value : -15
5G Throughput Recommendations
NRBTS.rlcProf4.tStatusProhibit
● Default value : 3
●
Recommended value : 4
5G Throughput Recommendations
NRCELL.ullaDeltaSinrMax
● Default value : 150
●
Recommended value : 10
●
Description : To allow OLLA rooms to adjust MCS
5G Throughput Recommendations
NRCELL.beamSet.basicBeamSet
● Default value : 1
●
Recommended value : 7
●
Description : beamset_6_2 is providing best averaged throughput in
drive tests, beamset_6 and beamset_5_3 are also providing good
performance.
5G Throughput Recommendations
NRCELLGRP.csiReportPeriodicity
● Default value : 320
●
Recommended value : 40
5G Throughput Recommendations
NRCELL.actBeamforming
● Default value : 0
●
Recommended value : 1
5G Throughput Parameters
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Downlink MIMO mode : 30
●
Number of SDU’s to discard : 1
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Uplink DMRS additional position : 255
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Radio link outage path loss threshold : 130
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CSI-RS tracking period : 80
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Delta SINR minimum of UL OLLA : -30
5G Throughput Parameters
●
Activate non-GBR service differentiation : 0
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Activate DL MU-MIMO : 0
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Delta CQI minimum of DL OLLA : -30
●
PUCCH F2 Max Code Rate : 15
●
Queue delay SDU discard enabled : 1
5G Throughput Parameters
●
UL Data split threshold : 100
●
SDU discard interval timer : 100
●
DL flow control algorithm : 0
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Number of SDU’s to discard : 1
●
Initial MCS for UL transmission : 0
●
BLER target for UL transmission : 10
5G Throughput Parameters
●
Timer poll retransmit UL : 45
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PDCP buffer discarding enabled : 1
●
UL MCS for SCell deactivation : 3
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UL Data split threshold : 100
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Timer reordering : 100
●
DL flow control algorithm : 0
5G Throughput Parameters
●
Default DL traffic routing : 1
●
Initial MCS for UL transmission on supplemental UL carrier : 0
●
Radio link resume SINR threshold : -30
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Initial MCS for DL transmission : 3
●
Maximum UL transmit power on own cell : 20
●
DRx profile 1
5G Throughput KPI
●
5G Residual BLER in PUSCH using 64 QAM MCS table
●
5G Average UE related SINR for PUSCH in Rank 2
●
5G Active cell MAC PDU throughput on PUSCH on initial HARQ
transmissions.
●
5G Average cell MAC PDU throughput on PUSCH on initial HARQ
transmissions.
●
5G F1 data split ratio in UL.
5G Throughput KPI
●
5G Average number of active UE’s with data in the buffer for DRBs in
the UL.
●
5G MAC SDU data volume received in UL on DTCH.
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5G NSA PDCP SDU throughput (without repetitions ) in DL.
●
5G NSA PDCP SDU throughput (without repetitions ) in UL.
●
5G MAC PDU Cell throughput on active PDSCH data slots on initial
HARQ transmissions.
5G Throughput KPI
●
5G PRB utilization for PDSCH
●
5G Average number of active UE’s with data in the buffer for DRB’s in
DL.
●
5G F1 data split radio in downlink
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5G Average UE related SINR for PUSCH in Rank 2
●
5G Average UE related RSSI for PUSCH
5G Throughput KPI
●
5G Maximum number of active UEs with data in the buffer for DRBs in
UL.
●
5G F1 data split ratio in DL.
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5G average wideband CQI, 64QAM table
●
5G average wideband CQI, 256 QAM table
●
5G PDCP SDU data volume transmitted without repetitions in DL.
5G Throughput KPI
●
5G PDCP SDU data volume transmitted without repetitions in UL.
●
5G average MAC layer user throughput in DL
●
5G average MAC layer user throughput in UL
●
5G usage ratio of PDSCH data slots over all DL data slots.
●
5G PRB utilization for PUSCH
●
5G Latency Recommendations
5G Latency Recommendations
NRCELLGRP.csiReportPeriodicity
● Default value : 320
●
Recommended value : 80
5G Latency Recommendations
NRCELL.actCDrx
● Default value : 0
●
Recommended value : 1
5G Latency Recommendations
NRCELLGRP.csiReportPeriodicity
● Default value : 320
●
Recommended value : 40
5G Latency Recommendations
NRCELLGRP.actProactUIScheduling
● Default value : 0
●
Recommended value : 1
5G Latency Recommendations
NRCELLGRP.ulSchedTimeInterval
● Default value : 40
●
Recommended value : 200
5G Latency Recommendations
NRCELLGRP.csiReportPeriodicity
● Default value : 320
●
Recommended value : 160
5G Latency Parameters
●
DRX Scheduling weight for UL enabled : 0
●
DRX Scheduling weight for DL enabled : 0
●
DRX Retransmission timer for DL : 24
●
UL scheduling time interval : 40
●
DRX Inactivity timer : 4
●
DRX on duration timer : 7
5G Latency Parameters
●
Activate connected DRX : 0
●
CSI Reporting Periodicity : 320
●
DRX long cycle : 3
●
Activate UL proactive scheduling : 0
5G Latency KPI’s
●
5G Average estimated X2 round trip delay between CU and MAC eNB.
●
5G Average estimated F1 round trip delay between CU and MAC DU.
5G Accessibility
Accessibility
●
It is one of the important feature in network radio access.
●
Three major sub-areas which can be identified for the accessibility
domain are : coverage, Radio access (RACH) and Radio Admission
control.
Radio Admission control
●
High loads always lead to high usage.
●
The main purpose of the admission control is to manage the use of
radio resources by accepting or rejecting requests.
Radio Admission control
The basic threshold for accepting and rejecting
● Number of active UE’s operating in NSA mode 3x per 5G cell group.
●
Number of active UE’s operating in NSA mode 3x per 5G cell
●
Number of non-GBR DRBs of active UE’s operating in NSA mode.
Call setup rejection causes
●
Lack of CP-UE capacity
●
Lack of non-GBR capacity
●
Lack of NSA user capacity
●
Lack of PUCCH capacity
Random Access
●
The UE requests the connection to the network using the procedure
known as the Random Access Procedure Via common uplink
resources.
●
In NSA mode, based on the RRC connection Reconfiguration message,
UE detects PSS, SSS, PBCH of NR gNB.
●
Once it successfully detects PSS,SSS,PBCH of NR gNB, it performs RACH
procedure to PS Cell of the gNB.
Random Access
The main purpose of RACH procedure is to:
● Obtain the resources for msg3.
●
Initial L1 synchronization (Timing and power)
Random Access
Random Access Procedure is needed in the following cases (NSA and SA
cases) :
● Initial access/SgNB addition
●
Loss of UL synchronization
●
Handover/RRC connection re-establishment
●
Beam recovery request
●
Transition from RRC_INACTIVE
Random Access procedure monitoring
●
NR_5010a : it counts the 5G contention free RACH setup attempts.
●
RA setup attempt for dedicated preambles corresponding to SSB
beam ID (0-63).
●
NR_5011a : that measures the 5G contention free RACH setup success
ratio.
Random Access procedure monitoring
●
RA Setup completions for dedicated preambles. The contention free
random access procedure is used in case of NR Cell handover. For
initial access, the CFRA procedure is triggered.
●
NR_5012a : that counts 5G contention based RACH setup attempts.
Coverage
Typical coverage issues and related KPI
● Coverage optimisation is needed when the actual measurements are
different from expectations based on link budget calculations.
●
When the link budget is below expectations i.e when a target service is
not satisfied at cell edge conditions, there is coverage gap.
●
The cell coverage can be limited either in UL or in DL.
●
In 5G, UL is the limiting path as UE Tx power is shared between LTE and
NR.
Coverage
Typical coverage issues and related KPI
● When there is excessive coverage, inter-cell and /or inter-beam
interference can occur.
●
The coverage can be reduced via power reduction, mechanical or
electrical tilting, re-azimuthing, antenna opening reduction.
●
The cell distance through TA commands distribution can be checked
to verify min/avg/max distance of UE to the cell.
5G Mobility
Mobility
Mobility scenarios and related KPIs
● In NSA mode, there are several mobility scenarios involving both LTE
and NR cells, as UE may be moving from one NR cell to a neighbor cell
or from one LTE cell to neighbor LTE cell.
●
Mobility scenarios are described as : Inter-DU/Intra-gNB HO, Inter-CU
/gNB HO , Intra-MeNB LTE handover without en-gNB change,
Inter-MeNB LTE handover without en-gNB change.
Mobility
Mobility scenarios and related KPIs
● Both intra-frequency intra-gNB and inter-gNB mobility are supported.
●
Inter-frequency mobility is not supported in this.
Mobility
Handover success rate can be monitored through following KPI’s :
● 5G Intra-gNB Intra-frequency PSCell change total success ratio.
●
5G Inter-gNB Intra-frequency PSCell change total success ratio on
target gNB.
●
5G Intra-gNB Intra-frequency PSCell change
Mobility Measurements
●
Mobility measurements are based on RSRP/RSRQ like in LTE.
●
There is no Cell Reference signal like in LTE,but several reference
signals (SS, CSI, RS) with different measurements.
●
RSRP,RSRQ and SINR are based on Synchronization signals only.
●
SS-RSRP is defined as the linear average over the power contributions
of the resource elements that carry secondary synchronization signal.
Mobility Measurements
Reference points:
● For FR below 6GHz : antenna connector of the UE.
●
For FR above 6GHz : SS-RSRP is measured based on the combined
signal from antenna elements corresponding to a given receiver
branch.
Mobility Measurements
SS-RSRP mapping:
Reported
Value [dbm]
0
RSRP < -156
1
-156 <= RSRP <= -155
...
126
-31<= RSRP <= -30
127
-30 <= RSRP
Mobility Measurements
SS-RSRQ is specified as the ratio N*”SS-RSRP”/”NR carrier RSSI”
Where
● N - the number of resource blocks in the NR carrier RSSI measurement
bandwidth.
●
NR carrier received signal strength indicator (NR carrier RSSI)
comprises the linear average of the total received power observed in
OFDM symbols of measurement time resources.
Mobility Measurements
Reference points:
● For FR below 6GHz : antenna connector of the UE.
●
For FR above 6GHz : SS-RSRQ is measured based on the combined
signal from antenna elements corresponding to a given receiver
branch.
Mobility Measurements
SS-RSRQ mapping:
Reported
Value [db]
0
RSRQ < -34
1
-34 <= RSRQ <= -33.5
...
126
28.5<= RSRQ <= 29
127
29 <= RSRQ
Mobility Measurements
SS-SINR is defined as the linear average over the power contribution of the
resource elements carrying secondary synchronization signals divided by
linear average of the noise and interference power contributions over the
RE carrying SS signals within the same frequency bandwidth.
Mobility Measurements
Reference points:
● For FR below 6GHz : antenna connector of the UE.
●
For FR above 6GHz : SS-RSRQ is measured based on the combined
signal from antenna elements corresponding to a given receiver
branch.
Mobility Measurements
SS-RSRQ mapping:
Reported
Value [db]
0
RSRQ < -34
1
-34 <= RSRQ <= -33.5
...
126
28.5<= RSRQ <= 29
127
29 <= RSRQ
Handover Preparation Optimisation
Handover Preparation Optimisation
●
This phase is subject to Radio Admission control as any new call setup.
●
The rejection of handover at admission control can be monitored
through various KPI.
Handover Preparation Optimisation
Lack of non-GBR capacity
● This can be monitored through KPI “5G Non-GBR DRB radio admissions
success ratio for NSA user in handover”.
●
It represents the rejection ratio of radio admission requests for NSA
user due to lack of non-GBR capacity in the handover phase.
●
It can be improved by increasing the value of parameter
NRBTS.NRCELLGRP.addNumOfNonGBRBearersHo.
Handover Preparation Optimisation
Lack of NSA user capacity
● This can be monitored through KPI “ 5G Radio admission success ratio
for NSA user in handover[%] which represents the rejection ratio of
radio admission requests for NSA user due to lack of NSA user
capacity in the handover phase.
●
It can be improved by increasing the value of parameter
NRBTS.NRCELLGRP.addnumOfHo/users
Handover Execution Optimisation
●
Handovers between 5G cells are possible based on the event A3 or
event A5 radio conditions measured in RSRP/RSRQ domain.
●
Event A3 parameters need to be optimised according to radio
environment : low values are good for fast moving UEs but can create
too many ping pong handovers.
●
A3 parameters have been increased to reduce ping-pong between
cells.
Neighbour cell declaration
Neighbour relations between 5G cells are using NRREL object class
(MRBTS/NRBTS/NRCELL)
● The neighbor relations from a given 5G cell are possible only for cells
for which the NRREL objects are defined in the NRCELL object relevant to
the source cell.
●
Upto 256 NRREL objects can be created per 5G NRCELL object( 1 radio
cell - can be multiple NRCELLs per DU)
Other Mobility parameters
●
Parameters related to NRHOIF objects are listed in mobility domain.
●
They are related to inter-frequency mobility and SA configuration.
5G Retainability
Retainability
●
Call drop ratio is one of the most important factor to check network
performance.
●
The main reason of call drop is Radio link failure.
●
Call drop occurs whenever voice or data cutoff before parties cutoff.
RLF types
●
UE initiated RLF handling
●
SgNB initiated RLF handling
Reasons for UE initiated RLF on 5G side:
●
Random Access procedure failure
●
DL out of sync
●
RLC failure - maximum number of retransmissions is reached.
●
SCG reconfig & SRB3 integrity failure
Procedure :
●
Upon RLF detection, UE informs MeNB the message
ScgFailureInformation msg which passes information to SgNB.
●
After receiving SCGFailureInformation, MeNB makes a decision if SgNB
change or SgNB release will happen.
●
In case of PSCell change, MeNB forwards information to SgNB via SgNB
Modification request over X2 interface.
Procedure :
●
When receiving SgNB Modification request, PSCell change procedure is
started.
●
Radio link recover timer is set.
●
During the waiting RL recover timer, the UE data is switched to LTE leg.
●
The SgNB sends in SgNB Modification request Ack message.
Procedure :
●
If NRBTS.tWaitingRIRecover expires before PSCell is changed, SgNB will
release the UE context, by sending a “SgNB release Required” with the
cause : ‘Radio connection with UE lost’ to MeNB.
●
If PSCell change procedure is failed, SgNB release is triggered too: “
SgNB Release required” msg is sent by SgNB to MeNB.
RLF - SgNB initiated RLF :
SgNB detects RLF for 5G link based on:
● DTX detection for requested DL HARQ feedback on PUCCH.
●
DTX detection of CSI reports on PUCCH
●
RLC failure - maximum number of retransmission is reached.
RLF - SgNB initiated RLF :
●
SgNB initiated RLF was not recommended to be activated, as DTX
detection of CSI reports on PUCCH, would be triggered too often and
caused SgNB release, therefore reducing the coverage.
RLF - SgNB initiated RLF-DTx for DL HARQ
Feedback :
●
SgNB counts the number of consecutive DTX detection for requested
DL HARQ feedback.
●
If number of consecutive DTX exceeds 35, SgNB starts RLF guard timer
NRBTS.
●
If RLF guard timer will expire, gNB-DU will inform gNB-CU about RLF by
sending UE context Modification required over F1 link.
5G Throughput & Latency
Throughput
●
For throughput domain, the first step is to identify peak data rates at
the physical layer.
●
Parameters impacting throughput are: NARFCN, cell technology,
channel bandwidth, TDD frame structure, 256 QAM, DL MIMO mode, UL
MIMO Mode, PRACH configuration index, SS burst set period, CSI RS
tracking period, DMRS position, beamforming, and number of
Transmitted SS blocks.
Throughput
Low MAC throughput could be linked to different reasons :
● Low rank
●
Decreasing PBCH block power
●
Activate additional DMRS
Throughput
●
The UL throughput is mostly influenced by the required quality of the
received signal.
●
In order to reach the required quality, the UE adjusts its power of
PUSCH channel transmission.
●
Low MAC throughput could be High UL BLER.
Throughput
The Main functional areas which can improve the DL and UL throughputs
are:
● Additional DMRS
●
SSB power : ssPbchBlockpower
●
Basic beamset
●
inter-gNB mobility
●
SU-MIMO
Throughput
●
256 QAM modulation
●
Link adaptation
●
Split bearer
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PDCP/RLC/HARQ configuration
●
UL:DL ratio & Frame structure
●
SSB Bursts and CSI RS tracking periodicities
Impact of mobility
●
Lack of 5G mobility may have a negative impact on the throughput.
●
5G radio conditions may be degraded in serving 5G NR cell due to
interference from the neighboring cells.
5G Latency
●
Proactive scheduling improves the latency.
●
It does not degrade the capacity.
●
It doesn’t impact the multi-UE uplink throughput but degrades the
mono-UE uplink throughput.
●
It is also likely to create more uplink interferences.
5G Latency
●
CSI report periodicity drives the scheduling request opportunities .
●
It is directly related to the capacity as the CSI reports are sent over
PUCCH channel.
Handover Parameter Optimisation
Handover Parameter Optimisation
●
It is an important function of the Self-optimisation network.
●
It was introduced by 3GPP for solving the mobility issues in 4G and 5G
networks.
●
Functions offered by SON such as MRO (Mobility Robustness
optimisation) and LBO (Load balancing optimisation).
Handover Parameter Optimisation
●
MRO was initially proposed in LTE-A, as part of SON, where it sets
parameters such as handover margin (HOM) and time to trigger (TTT)
to maintain communication links throughput user movements with a
minimum number of overlapping operators.
●
MRO automatically adjusts the values of parameters (HCP) to preserve
the quality of the system.
Handover Parameter Optimisation
●
By adjusting these parameters, handover failure (HOF) rates are
reduced and thus improved QoS.
●
HPO functionality is important in deploying 5G networks.
●
It is very important to automatically adjust the HCP settings to
maintain the quality of the network.
●
The main methods for improving the performance of 5G network
mobility is optimising HCP settings.
Handover Parameter Optimisation
●
If HCP’s are set to static settings, continuous connection will be
adversely influenced, particularly when UE speed is high.
●
Therefore, HCP settings must be modified to resolve this deficiency.
●
HPO function as submitted by 3GPP as a primary feature in 5G network
deployment.
Handover Parameter Optimisation
●
HO optimisation between femto and macro BS is also important.
●
Currently, mobility with high requirements within 5G networks (such as
mm Waves and lower latency) has led to the requirement of the HPO
algorithms.
●
Many affecting factors must be considered to estimate appropriate
HCP settings which are distance, interference, channel state , resource
availability , noise and UE speed.
Steps of Network Optimisation
Network Optimisation steps
● Understand
It means to understand user demands from the 5G network. CSP’s must be
ready to adapt to the constantly changing demands.
Network Optimisation steps
● Measure
Network benchmarks are growing more expensive and dynamic in nature.
CSP’s must identify which key metrics to focus on and how we can
evaluate them effectively.
Network Optimisation steps
● Improve
Various AI powered identify gaps where key metrics fall short. It resolves
the issue across the full end-to-end network.
Network Optimisation steps
● Invest
Network optimization becomes integral to network investment planning. It
identify critical congestion areas that cannot be solved with optimization.
Network Optimisation benefits
●
Network optimization is effective in boosting network optimization.
●
It ensure superior network experience and easier network operations,
without the need for capacity expansion.
●
Network optimization is proven to produce many direct and indirect
benefits on both network and business performance.
Maximize ROI
●
31% reduction of cells with poor spectral efficiency.
●
15% increase in DL user throughput during busy hours.
●
10% reduction unplanned carrier expansions
Improve UE
●
15% user experience improvements.
●
20% increase in deployment capacity.
●
70% reduction in customer complaints.
●
90% external benchmark wins
Future proof operations
●
4x larger network managed with the same team.
●
50% faster site acceptance
●
3.4% decrease in site power consumption.
5G NR Network Optimization Features
Optimisation features
5G NR network optimization tools provide a view of 5G network quality and
coverage.
●
By optimizing network, operators can minimize the churn caused by
quality issues and ensure the high capacity of 5G networks.
●
New NR technologies, such as beamforming and m MIMO, can be
verified with the 5G NR wireless network optimization tools.
Optimisation features
●
Nemo solutions offer a holistic view of the network coverage and
quality, enabling effective troubleshooting and optimization with
automated reporting.
●
Nemo tools come with an easy to use GUI with over 2000 KPI’s and
support for the latest technologies such as 5G NR NSA/SA, LTE-A,
NB-IOT and LTE-M.
Optimisation features
Nemo optimization tools support features such as:
● Coverage analysis
●
Interference analysis
●
Handover performance
●
Neighbor cell analysis
Optimisation features
Nemo optimization tools support features such as:
● Overspilling
●
Cross feeder analysis
Optimisation features
Optimization tests reflect the latest 5G NR network performance of :
● Voice and video quality e.g call setup success rate, completed call
rate, dropped calls, blocked calls, call setup time, MOS, call failure
reason analysis.
●
Data connection e.g file download speed, file upload speed, network
latency, web browsing time, data connection failure reason analysis ,
OTT application performance.
5G NR Network Advanced Optimization
Features
Optimisation features
Beam coverage visualization
● 3D visualizer add-on helps in seeing the signal behavior in practice
related to the environment objects.
●
Visualizer allows you to verify beam configurations by comparing
measurement data to the planned beam structure.
●
In this, both horizontal and vertical beams can be analyzed by
combining street-level walk or drive tests to UAV measurements.
Optimisation features
●
5G-LTE coverage comparison
●
Low coverage detection
●
High interference detection
●
Pilot pollution analysis
●
Cell dominance analysis
●
Network slicing testing and analysis
Optimisation features
●
mMIMO result analysis
●
o-RAN network troubleshooting and analysis
●
Binary logging
●
Dynamic spectrum sharing (DSS) for 5G
5G NR Network Optimisation use cases
5G NR network optimization solution offers various optimization use cases :
● Remote management of 5G measurements and measurement
solutions with Nemo cloud.
●
5G NR drive testing
●
In-building 5G measurements
●
Unattended 5G measurements
●
Post-processing of data
5G NR Network Optimisation use cases
5G NR d