01 Rankpi o2 Uk Rrm Features

1Company Confidential 2008 Nokia O2 UK RANKPI RRM overview Features1

Company Confidential 2008 Nokia

Radio Resource ManagementNSN Nokia

O2 UK RANKPI RRM overview Features

2Company Confidential 2008 Nokia O2 UK RANKPI RRM overview Features

Radio Resource ManagementRel99 content

Parameter Split (InitialAndMinAllowedBitrateUL/DL)

Dynamic Link Optimisation Overload Control (RAS05) Throughput based optimisation of Packet Scheduler algorithm

Flexible Upgrade for NRT services Load and Service based handovers

Power balancing Radio Access Bearer Combinations


Nokia WCDMA Rel99 Packet Scheduler

Nokia Packet Scheduler2 entities defined: UE specific and Cell specific Packet Scheduler

HCUE

specificPS

PS cell #1

PS cell #2

PS cell #n

L3 SignallingServices

RRCNBAP

UL Capacity request

Active set infoCells in theactive set

TFCS and DLSCnegotiation

L2

MACDL Capacity request

(UL TFCS, DL TFCS)

(UL TFCS, DL TFCS, DLSC)

UE specific part: Traffic Volume measurement management, Retry incase of congestion,UE radio access capabilities, throughput measurements

Cell specific part: Cell load information, CR queuing, Channel type selection, Bit rateallocation, Priority based scheduling, PS interuption timer

Common: DyLO and RT-over NRT pre-emption

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Company Confidential 2008 Nokia O2 UK RANKPI RRM overview Features

Nokia Packet SchedulerNokia Packet Scheduler consists of many features:

Dynamic Link Optimisation

Tunable Inactivity Timers

Radio interface overload triggerd downgrade

Enhanced Priority based Scheduling

Packet Scheduler retry with lower bitrate in congestion

Packet Scheduler Interuption Timers

RT-over NRT pre-emption (AC)

Throughput based optimisation of Packet Scheduler algorithms

RAN1.5

RAN1.5

RAN1.5

RAS05

RAN04

RAS05

RAS05.1

Flexible Upgrade for non real time (NRT) services RAS05.1

RAN1.5

Enhanced Overload Control (RAS05)

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Existing Parameter split

InitialAndMinAllowedBitRateDLInitialAndMinAllowedBitRateUL

Existing Parameter splitWCEL: InitialAndMinAllowedBitRateDL(UL)

WCEL: InitialBitRateDL(UL) WCEL: MinAllowedBitRateDL(UL)

old

new

Range : 8, 16, 32, 64, 128, 256, 384 kbpsDefault: 64 kbps

Range : 8, 16, 32, 64, 128, 256, 384 kbpsDefault: 8 kbps

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Scheduled Bitrate DL [kbps]

128

64

32

0

InitialBitRate (64)

MinAllowedBitRate (32)

No scheduling allowed

Example:

t


Uplink Link Adaptation

Uplink link adaptation supported since RAN1.5 UL TFC selection is standard UE operation as in 3GPP TS 25.133. No support from

RAN required. TFC selection enables fast link adaptation with 20 ms period. If the mobile reaches its maximum power, it selects the appropriate transport

format to adjust the data rate automatically. As soon as the link conditions improve, the data rate increases back up to the

maximum.

DPCCH DPCCH DPCCH DPCCH

384 kbps

DPCCH DPCCH DPCCH DPCCH

384 kbps

128 128 64 64

384 kbps

384 kbps

UE hits max power data rate

reduced Conditions improve data rate increased back to 384 kbps

20 ms 20 ms 20 ms 20 ms

DPCCH = dedicated physical control channel

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Dynamic Link Optimisation

Dynamic Link Optimisation for NRT servicesNon real-time service will be downgraded in case the downlinkradio link power reported from WBTS exceeds maximum allowed power

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RNC: DLOptimisationUsage

128 kbps coverage

384 kbps coverage

Range : 0 Feature is not activated1 Feature activated SF step 12 Feature activated SF step 2

Default: 1

RRC: RadioBearerReconfiguration appliedDLO = Dynamic Link Optimisation

Dynamic Link Optimisation for NRT services

time

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PtxRL

Ptxave

Triggering of DyLOPtxmax

NBAP: RadioLink MeasurementReportNBAP: DedicatedMeasurementReport

Sliding Window

WBTS: DLORLAveragingWindowRange : 1 .. 10 Step 1 Default: 0

Sliding Window

Sliding Window

Averaging RL Measurement data from WBTS

Dynamic Link Optimisation for NRT servicesGuard Timer after DLO was triggered

PtxRL

Ptxave


Offset

RNC: DLOptimisationPwrOffsetRange : 0 .. 6 dB, Step 0.1 dBDefault: 2 dB

RNC: DLOptimisationProhibitTimeRange : 0 .. 120 sec, Step 1 sec Default: 2 sec

no Triggering of DyLO

Triggering of DyLO

Guard Timer

time

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NBAP: RadioLink MeasurementReportNBAP: DedicatedMeasurementReport

Dynamic Link Optimisation for NRT services

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time

PtxRL

Ptxave


Offset

NBAP: RadioLink MeasurementReport

no Triggering of DyLO Triggering of DyLO

NBAP: DedicatedMeasurementReport

Guard Timer

Guard Timer after flexible upgrade was triggered

Flexible Upgrade

Example DyLO scheme 1: PtxDLabsMax 50 dBm, PtxTotalMax 43dBm

WCEL: PtxDLabsMax = 50 dBm

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PtxTotalMax 43dBm

PtxPrimaryCPICH 33dBm

PtxPrimaryCPICH CPICHtoRefRABoffset = 31 dBm

Calculated max RL pwrCalculated max RL pwr

This is where DyLO triggers. (If PtxDLabsMax is set high)

max,txP

Ptx, threshold

RNC: DLOptimisationPwrOffset

reftxP ,

Example DyLO scheme 2: PtxDLabsMax 38 dBm, PtxTotalMax 43dBm

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PtxTotalMax 43dBm

PtxPrimaryCPICH 33dBm

WCEL: PtxDLabsMax = 38 dBm

Calculated max RL pwr

PtxDLabsMax = 36 dBm

PtxPrimaryCPICH CPICHtoRefRABoffset = 31 dBm

max,txP

reftxP ,

Ptx, thresholdRNC: DLOptimisationPwrOffset

PtxDLabsMax is reduced from 50dBm to 38dBmThis is where DyLO now triggers.

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Overload Control

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IuB

Air Interface

WBTS HW Resources

IuB/AAL2

UL interferenceDL transmisson power

WSP capacity (N*) E1 capacity / AAL2

Radio Resources

WBTS HW resources

IuB resources

Capacity Areas in UTRANMaximum capacity is available at a time, if all capacity areasare re-configured according real bandwidth requirements

RLC/MAC

Overload Control in Nokia RRMDifferent procedures to cope with WCDMA cell overload:

Uplink: Transport Format Combination Control (TFCC) by RRC Procedures

When the packet scheduler has detected an overload situation in the uplink, it schedules a subset of the original transport format combination set (TFCS) requests the RRC signalling entity of RNC to initiate the transport format combination control (TFCC) procedure. the RRC signalling entity sends an RRC: TRANSPORT FORMAT COMBINATION CONTROL message to the UE .

Downlink: Transport Format Combination (TFCC) Subset Method Enhanced Overload Control by Radio Link Reconfigurations

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When the packet scheduler has detected an overload situation in downlink it: selects Enhanced overload control if it is activatedor selects TFC Subset method and schedules a subset of the original transport format combination set reconfigures the L2 by sending the transport format combination subset to the UE-specific MAC-d entity of the RNC

UTRAN Overload Control

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If load in WCDMA cell is too high, Overload Control can start downgrading allocated DCH bitrates of UEs

Lower end of downgrade path is InitialAndMinAllowedBitrateUL and InitialAndMinAllowedBitrateDL bitrate, since PS can not schedule bitrates below

Once MinAllowedBitrate is allocated but still not enough air interface capacity available, DCH will be switched to CCH

If UE is performing Compressed Mode, CM will be stopped

Selection of Radio Bearers to be downgraded depends on RNC levelparameter

CrHandlingPolicyUL and CrHandlingPolicyDL : - see next 2 slides -

UTRAN Overload ControlSelection procedure for Radio Bearers to be downgraded

CrHandlingPolicyUL/DL = 1 ARRIVAL TIME ONLY:1.) Target Radio Bearers are selected in order of longest allocation time if more than one bearers with same allocation time identified, select the one with highest

allocated DCH bitrate

2.) Interactive or Background class bearers are switched from DCH to CCH

CrHandlingPolicyUL/DL = 2 ARRIVAL TIME AND BEARER CLASS:1.) Background Bearers are decreased in order of longest allocation time if more than one bearers with same allocation time identified, select the one with highest


2.) Interactive Bearers are decreased in order of longest allocation time if more than one bearers with same allocation time identified, select the one with highest


3.) Background Bearers are switched from DCH to CCH in order of longest allocation time

4.) Interactive Bearers are switched from DCH to CCH in order of longest allocation time

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UTRAN Overload ControlSelection procedure for Radio Bearers to be downgraded

CrHandlingPolicyUL/DL = 3 ARRIVAL TIME, BEARER CLASS AND THP:1.) Background Bearers are decreased in order of longest allocation time if more than one bearers with same allocation time identified, select the one with

highest allocated DCH bitrate

2.) Interactive Bearers are decreased in order of highest THP value set and longest allocation time

if more than one bearers with same allocation time identified, select the one with highest allocated DCH bitrate

3.) Background Bearers are switched from DCH to CCH in order of longest allocation time

4.) Interactive Bearers are switched from DCH to CCH in order of highest THP value and longest allocation time

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UTRAN Overload Control- procedure -

Move to nextlower bit rate

NO

PrxTotalNew >PrxTarget

&&PrxTotalChange > Scheduling Period or RRI default value)

Enhanced Overload Control (3/3)OCdlNrtDCHgrantedMinAllocT

Range and Step: [0..60 sec], default : 60 sec ** recommended value : 10 sec ****note: if value is 60 sec, enhanced overload control is NOT ACTIVE

This parameter defines the threshold for an NRT DCH allocation time in an enhanced overload control for DL NRT traffic. If the NRT DCH allocation time is longer than the parameter defines, the DCH bit rate can be decreased and the SF can be increased, or the DCH can be released to get the CELL load to an acceptable level from the overload situation.

When overload is detected and dedicated channel is modified using TFC subset or Enhanced overload control method, it takes some time before the decrease in load (PrxTotal and PtxTotal) as can be seen in RNC from the NBAP: RADIO RESOURCE INDICATION messages.

This delay may be longer than scheduling period and therefore it is necessary to wait that load control actions have effected, in order to prevent new unnecessary load control actions in the next scheduling period

The parameter LoadControlPeriodPS determines the period how often PS can perform load control actions

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t

AAL2 CAC

Cell overload detected

NBAP: Radio Link Reconfiguration Prepare

NBAP: Radio Link Reconfiguration Ready

NBAP: Radio Link Reconfiguration Commit

AAL2 resource change req

AAL2 resource change resp

RRC: Radio Bearer Reconfiguration

RRC: Radio Bearer Reconfiguration CompleteStart

Ongoing PS call Ongoing PS call

DCH downgrade

UTRAN procedures and signaling for overload controlRadio Link - & Radio Bearer re-configuration procedures in DL

Ongoing PS call

Radio Bearer selectionprocedure in Packet Scheduler

OCdlNrtDCHgrantedMinAllocT

DCHs untouched

.. waiting for updated loadmeasurements

CAC = Connection Admission Control

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IuB

Air Interface

WBTS HW Resources

IuB/AAL2

UL interferenceDL transmisson power

WSP capacity (N*) E1 capacity / AAL2

Radio Resources

WBTS HW resources

IuB resources

Capacity Areas in UTRANWhat capacity areas are reconfigured withRadio Link Reconfigurations ?

RLC/MAC

9

9 99

Enhanced Priority Based Scheduling Swapping Interference Capacity

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Enhanced Priority Based Scheduling

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RT traffic

NRT RB 1NRT RB 2

time

bit rate Reconfiguration of RB1Reconfiguration of RB1

Capacity request RB2Capacity request RB2 Timers to prevent reconfigurations for short

allocations-> no unnecessary signaling

Timers to prevent reconfigurations for short

allocations-> no unnecessary signaling

New user requests capacity in congestion

Triggered in case of congestion UL interference / DL power / downlink spreading code

BTS HW (WSP)

Iub AAL2 transmission congestion

Enhanced Priority Based SchedulingUplink

Decrease loadingIncrease loading

Bit rate allocation algorithm

PrxTotal < PrxTarget NOYES

PrxTotal

average throughput changing over time low utilization of resources

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threshold 1

threshold 2

Throughput based optimisation of PS algorithmActivation of the feature using bitstring:

Feature can be on or off seperately forInteractive and Background service classes taking into accountTraffic Handling Priority (THP) from QoS parameters:

RNC: PSOpThroUsage default: 0 0 0 0 (by default feature is off for non-GBR services)

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Background class

Interactive classe THP = 2Interactive classe THP = 3

Interactive class THP = 1

RANAP: RABassignmentRequest

(traffic class, THP included)

Throughput based optimisation of PS algorithmConcept

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L2 MACthroughput[kbps]

MAC-dentityTTI Transmission Time Interval

Upper downgradethreshold

Lower downgradethreshold

Release threshold

t

e.g. 384 kbps DCH is downgraded to 256 kbps

e.g. 128 kbps DCH is downgraded to 64 kbps

DCH is released FACH allocated

avg. L2 throughput

Sliding measurement window

Parameters introduced to control the downgrade/release of DCH

Throughput based optimisation of PS algorithmTTI

Different measurement window sizes can be defined for Upper, Lower or Release threshold:

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TTI Transmission Time Interval

TTI (64kbps) = 40 msTTI (384kbps) = 10 ms

Range and Step: 500 ms .. 10000 ms, 500 msDefault: 2000 msNote: Value 0 means that throughput measurements are not activated.

RNC: DCHUtilUpperAveWinBitRateRNC: DCHUtilLowerAveWinBitRate

Range and Step: 500 ms .. 10000 ms, 500 msDefault: 1000 ms -common for all bitrates-

RNC: DCHUtilRelAveWin

Downlink measurements: all transmitted bits are measuredUplink measurements: all correctly received bits are measured

Throughput based optimisation of PS algorithmExample for upper downgrade trigger MAC-d

entityL2 MAC throughput [kbps] / DCH Bitrate [kbps]Upgrade requests are rejected

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384

Upper downgradethreshold

t

RNC: DCHUtilUpperDowngradeThrBitRate

256

RNC: DCHUtilBelowDowngradeThrRange and Step: 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 %Default: 6 %

240.64 kbps = 256 kbps * ( 1 0.06 )= UpperDowngradeBitrate * ( 1 DCHUtilUpperDowngradeThr)Upper Threshold

RNC: DCHUtilLowerDowngradeThrBitRateRNC: DCHUtilReleaseDowngradeThrBitRate

TimetoTrigger

L2->L3: DCHUtil is low

Lower downgradethreshold

or + TrafficVolumePendingTimeUL/DL started

Measurement Window

(one parameter setting per supported Bitrate)

Throughput based optimisation of PS algorithmTime to Trigger

RNC: DCHUtilUpperTimeToTriggerBitrate (one parameter setting per supported Bitrate)

Range and Step: 0..20000 ms, 200 msDefault: 32 kbps: 4000ms, 64 kbps: 4000ms, 128 kbps: 4000 ms, 256 kbps: 4000 ms, 384 kbps: 4 000 ms

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RNC: DCHUtilLowerTimeToTriggerBitrate (one parameter setting per supported Bitrate)

Range and Step: 0..10000 ms, 200 msDefault: 32 kbps: 1400ms, 64 kbps: 1400ms, 128 kbps: 1400 ms, 256 kbps: 1400 ms, 384 kbps: 1400 ms

Time to Trigger is used to delay the sending of MAC-d utilization information from L2 -> L3

Throughput based optimisation of PS algorithmGuard Timer

After DCH downgrade a guard timer is started during that time it is not allowed to further downgrade the DCH bitrate due to L2 throughput measurements

RNC: DCHUtilMeasGuardTime

Range and Step: 0..30 sec ; 1 secDefault: 6 sec

DCH Bitrate [kbps]

384

256

[..]

Guard Timer applied

t

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Throughput based optimisation of PS algorithmRelease Threshold

L2 MAC throughput [kbps] / DCH Bitrate [kbps]

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t

[..]

Range and Step: 0..8000 bps; 32 Bit Default: 256 bps

RNC: DCHUtilRelThrDLRNC: DCHUtilRelThrUL

RNC: DCHUtilRelTimeToTrigger

e.g. 32

TimetoTrigger

Range and Step: 0..10000 ms, 200 msDefault: 200 ms

DCH FACH

MAC-dentity

L2->L3: Release request+ TrafficVolumePendingTimeUL/DL started

Measurement Window

Releasethreshold

Upgrade requests are rejected

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Throughput based optimisation of Packet Scheduler algorithmsTest results from Nokia Test Network (NTN) in Espoo

Testcase: Throughput Based Optimisation off

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1. Initial bitrate 64

2. Max bitrate 384

1 2

3. To Cell FACH

3

384

384

Inactivity time for 384 is 2s => CELL_FACH

64

UDP data

These red lines shows RRC

signalling like RB reconfiguations/c

omplete and measurement

reports/control

DL

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1 2 3 4 5


2. Max bitrate 384

3. Downgrade UL to 8

4. Downgrade 256

5. Downgrade to 128

6. To Cell FACH

6

256 also SF 8

Upper Averaging window=2sUpper time to trigger=4sLower Averaging window=2Lower time to trigger=1.4DCHutilGuardtime=6s

UL downgrade from 64 to 8 is ~ 7sec after initial. Downgrade is happening due the lower measurement but DCHutilguardtime(6s) is delaying downgrade

UL Downgrade ~7s

DL Downgrade ~7s DL Downgrade ~7s

DL

Testcase: Throughput Based Optimisation onDefault parameter settings

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2. Max bitrate 384

4. Downgrade to 256

5. Downgrade to 1286. To Cell FACH

1 2 3 4 5 6

Upper Averaging window=1sUpper time to trigger=2sLower Averaging window=1sLower time to trigger=0.8DCHutilGuardtime=2s


UL Downgrade ~5s

DL Downgrade ~4s DL Downgrade ~4s

DL

Testcase: Throughput Based Optimisation onFast parameter settings

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2. Max bitrate 384

4. Downgrade to 256

5. Downgrade to 128

6. To Cell FACH

1 2 3 4 5 6

Upper/lover Averaging window=4s/4sUpper/lower time to trigger=8s/2.8sDCHutilGuardtime=6s

UL is downgraded to 8

UL Downgrade ~8s

DL Downgrade ~13 s DL Downgrade ~13s

UL downgrade from 64 to 8 is ~ 8s after initial. Downgrade is happening due the lower measurements


DL

Testcase: Throughput Based Optimisation onSlow parameter settings

RB distribution with different test cases

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02.77

30.25

02.78

07.08

07.08

14.57

03.19

04.44

04.45

19.50

02.85

13.07

13.09

03.27

0%

20%

40%

60%

80%

100%

Thput "Off" Thput_Set 1default

Thput_Set 2"fast"

Thput_Set 3"slow"

12825638464

Picture below shows distribution of RBs during download with 4 different parameter set

Set2 fast show most optimal use of resources with UDP.

* Times are calculated between RB Reconfiguration completeMessages

When Throughput based optimisation is off, there is RB upgrade from initial (64) to maximum (384) but no downgrades

Throughput based optimisation of PS algorithmExample

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How downgrading Bitrates can be analysed with countersM1005 Dedicated NBAP procedure

Changing user bitrates with RL Reconfiguration

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NBAP: Radio Link Reconfiguration Prepare

NBAP: Radio Link Reconfiguration Ready

NBAP: Radio Link Reconfiguration Commit

AAL2 resource change req

AAL2 resource change resp

RRC: Radio Bearer Reconfiguration

RRC: Radio Bearer Reconfiguration Complete

DCH downgrade

AAL2 CAC

M1005C133 RL RECONF SYNCH FOR DCH MOD DUE TO DYN LINK OPT ON SRNCM1005C142 RL RECONF SYNCH FOR DCH MOD ON SRNC DUE TO CMM1005C153 RL RECONF PREP SYNCH FOR DCH DEL DUE TO PRIORITY BASED SCHEDULINGM1005C154 RL RECONF PREP SYNCH FOR DCH DELETION DUE TO PRE-EMPTIONM1005C156 RL RECONF PREP SYNCH FOR DCH DEL DUE ENHANCED OVERLOAD CONTROLM1005C158 RL RECONF PREP SYNCH FOR DCH MOD DUE PBS DOWNGRADINGM1005C159 RL RECONF PREP SYNCH FOR DCH MOD DUE PRE-EMPTION DOWNGRADINGM1005C239 RL RECONF PREP SYNCH FOR DCH MOD DUE THROUGHPUT BASED OPTIMISATIONM1005C240 RL RECONF PREP SYNCH FOR DCH DEL DUE THROUGHPUT BASED OPTIMISATION

Feature trigger

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Flexible upgrade of the NRT DCH data rate

Flexible Upgrade for NRT DCH Bitrates Flexible upgrade of NRT DCH bit rate enables bit rate upgrades from all

bit rate levels Upgrade is triggered based on UE or RNC internal capacity request and high

throughput measurements in UL and DL Maximized end-user throughput and optimal utilization of radio, WBTS HW

and IuB transmission resources

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NRT PS

bit rate

time

Example on UE level

Bit rate is upgraded when resources

becomes available

NRT PSNRT PS

AMRNRT PS user 1

bit rate

time

NRT PS user 2

bit rate

timebit rate

time

NRT PS user 3

DCH scheduling

Example on cell level

Bit rate is upgraded when resources

becomes availableRNC: FlexUpgrUsage [0,1] default: 0 feature = off

Flexible Upgrade for NRT DCH BitratesTransport Channel

Traffic Volume

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t

TrafVolThresholdDLHighBitRate / TrafVolThresholdULHighBitRate

Default: (one parameter value per Bitrate)Reporting Event Reporting Event

RNC: TrafVolThresholdDLHighBitRateRNC: TrafVolThresholdULHighBitRate

Range:8, 16, 32, 64, 128, 256, 512, 1024, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576 Bytes

Flexible Upgrade for NRT DCH Bitrates

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TVM = Traffic Volume Measurements

Flexible Upgrade for NRT DCH BitratesDynamic Link Optimisation(DyLO) triggedUE was put into a metal box DCH Bitrate

[kbps]FTP testing in german network(inhouse)

Nrnberg (Nov. 2006)

Filesize 1MB from Nokia serverlocated somewhere in internet

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Lightweight flexible Upgrade featuretriggers DCH Bitrate back to max Bitrate

384

128

32

Flexible Upgrade for NRT DCH BitratesDCH Bitrate [kbps] / L2 MAC throughput [kbps] Traffic Volume [Bytes]

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256

TimetoTriggerMeasurement Window

384

128

64

[..]

32 128

1024

2048

4096

RNC: DCHUtilHighBelowNRTDataRateThr

Range and Step: 0..30 % , 2 %Default: 6%

(128 kbps 128kbps * 6%) ~ 120 kbps

512

RNC: DCHUtilHighAveWin

Range and Step: 500..10000 ms , 500 msDefault: 1000 msNote: If value = 0, no throughput measurements active

RNC: DCHUtilHighTimeTo Trigger

Range and Step: 0..10000 ms , 200 msDefault: 200 ms

Capacity Request in RNC MAC layer

MAC-dentity

Maximum Bit Rate

High Bitrate detected

Flexible Upgrade of NRT DCH data rate

Flexible upgrade of NRT DCH data rate enables averaging of radio link measurements.

Separate operator controlled parameters for measurements used for:

Power change estimation in bit rate upgrade.

Dynamic link optimisation.

By averaging, the sensitivity of the algorithms can be controlled:

Adaptation to the changes in application throughput and radio conditions.

Avoiding unnecessary up- and downgrades.

Optimised throughput and resource utilisation

10

15

20

25

30

35

40

45

0 100 200 300 400 500 600 700 800

Time (seconds)

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No averaging, DLO is triggered

Averaged, DLO is not triggered

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Load and Service based Handover

Load and Service Based Handover Procedure

Load based handover

Load based handover

Service based

handover

Service based

handover

Constant monitoring of loadingHO

triggersPeriodical checking

Selection of connections to

be handed over

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MeasurementsExecute

handoversHandover decision

Service Based Handover Procedure

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Service based handover frequency (WCEL): ServHOPeriodInterFreq [0..120sec], step 1s, default: 30 sec; 0= off ServHOPeriodInterRAT [0..120sec], step 1s, default: 30 sec; 0= off

Service based handover frequency (WCEL): ServHOPeriodInterFreq [0..120sec], step 1s, default: 30 sec; 0= off ServHOPeriodInterRAT [0..120sec], step 1s, default: 30 sec; 0= off

Max number of RRC connections per service based handover phase (WCEL): ServHONumbUEinterFreq [1..255], step 1, default: 16 ServHONumbUEinterRAT [1..255], step 1, default: 16

Max number of RRC connections per service based handover phase (WCEL): ServHONumbUEinterFreq [1..255], step 1, default: 16 ServHONumbUEinterRAT [1..255], step 1, default: 16

WCDMA cell

HO candidates

Maximum number of UE in Load based HO procedure The number of connections to be handed over due to load

reasons is set by RNC configuration parameters (WCEL)

LHOnumbUEinterFreq

This parameter defines the number of UEs that are simultaneously in a load-based inter-frequency handover procedure.

Range and Step: 0..32, step 1Default : 0Note: 0 means Load based HO for inter-frequency (f2, f3) is disabled.

LHOnumbUEinterRAT

This parameter defines the number of UEs that aresimultaneously in a load-based inter-RAT handoverprocedure.

Range and Step: 0..32, step 1Default : 0Note: 0 means Load based HO for inter-system (GSM) is disabled.

RNC configuration parameter (WCEL) defines how many UEs can be simultaneously in the compressed mode in certain cell due to service or load based handover procedures

MaxNumberUEcmSLHO

Range and Step: 0..32, step 1Default: 6

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Load and Service based HandoversService Types subject for Load and Service HO

Each service type can be enabled for load/service/load and service/none.This is operator specific setting according layer and handover strategy.

RNC level parameters:

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Range: None (0), Load HO (1), Service HO (2), Service and Load (3)

Default: None (0)

SLHOUseConvCSSpeechSLHOUseConvCSTDataSLHOUseConvPSRTDataSLHOUseConvPSSpeech

SLHOUseBackgroundPSNRTData

SLHOUseInteractivePSNRTDataSLHOUseStreamCSNTDataSLHOUseStreamPSRTData

System priority table in RNC defines prefered system or hierachicalWCDMA layer

If Iu interface service priority information is not available, RNC based service priority handover profile table is used instead

In addition it defines preferred target hierarchal cell layer inside WCDMA system and that information can also be used to improve information received in the Service Handover IE

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Service typeService typeConversational, CS speechConversational, CS speechConversational, CS-T dataConversational, CS-T dataConversational, PS speechConversational, PS speechConversational, PS RT dataConversational, PS RT dataStreaming, CS-NT dataStreaming, CS-NT dataStreaming, PS RT dataStreaming, PS RT dataInteractive, PS NRT dataInteractive, PS NRT dataBackground, PS NRT dataBackground, PS NRT data

Preferred system/layerPreferred system/layerGSMGSMWCDMAWCDMAWCDMAWCDMAWCDMAWCDMAWCDMA macroWCDMA macroWCDMA macroWCDMA macroWCDMA microWCDMA microNot definedNot defined

RNC level parameters:

SLHOprofileConvCSspeech

SLHOprofileConvCSTdata

SLHOprofileConvPSspeech

SLHOprofileConvPSRTdata

SLHOprofileStreamCSNTdata

SLHOprofileStreamPSRTdata

SLHOprofileInteractivePSNRTdata

SLHOprofileBackgroundPSNRTdata

Load and Service based HandoversLoad of the source cell

(GSM or WCDMA) Powerful handover enhancement forload and service sharingPowerful handover enhancement forPowerful handover enhancement for

lloadoad andand sserviceervice ssharingharing

100%

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Load and Service basedhandovers according toservice priorities

Effective integration of GSMand WCDMA

WCDMA layer management

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Example of service priority table in RNC

Service Preferredsystem/layer

Conv. CS speech

Conv. CS transparent data

Conv. PS speech

Conv. PS RT data

GSM

GSM

WCDMA, macro

WCDMA, micro

Streaming CS non-transp. GSM

Streaming PS RT data WCDMA, micro

Interactive PS NRT data WCDMA, micro

Background PS NRT data WCDMA, micro

only Service basedhandovers

0%

Total interference

NRT rejection rate

Spreading code usage

HW / logical resource

usage

Downlink

Total power

NRT rejection rate

Triggers set by operator

Hard blocking ratio of

- BTS/WSP- AAL2- RLC/MAC/DSP

Hard blocking ratio of

- BTS/WSP- AAL2- RLC/MAC/DSP

Triggering of Load based Handovers

Uplink

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NRT PS capacity request

rejection rate

After one of the reasons are fullfilledcell is in theload based handover state

DL spreading

code usage

HW / logical resource

usageTotal UL/DL

power

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Triggering of Load based Handovers Trigger Reasons

Air Interface Interference and Power

LHOPwrOffsetUL = - 1.5 dB relative to PrxTarget

PrxTotal > PrxTarget + LHOPwrOffsetUL

PtxTotal > PtxTarget + LHOPwrOffsetDL

LHOPwrOffsetDL = - 0.7 dB relative to PtxTarget

Headroom for CM triggering must be considered also

RNC checks based on RRI interval:

Range and Step: [-10..0 dB] ,0. 1dBDefault value: - 0.7 dB

Range and Step: [-30..0 dB] ,0. 1dBDefault value: - 1.5 dB

Non-GBR Capacity Request Rejection Rate


Measurement Report (e4a) Capacity Request

RNC internal Capacity Request (MAC layer)

CapaReqRejRateUL = RejectedRequestsCellUL

(AllCapacityRequestsCellUL + LHONRTTrafficBaseLoad )

CapaReqRejRateDL = RejectedRequestsCellDL

(AllCapacityRequestsCellDL + LHONRTTrafficBaseLoad )

RNC checks based on 1 sec intervals:

CapaReqRejRateUL > LHOCapaRejRateUL and CapaReqRejRateDL > LHOCapaRejRateDLRange and Step: [0..100 %] , 1%Default value: 70 %

Range and Step: [0..100 %] , 1%Default value: 70 %

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Company Confidential 2008 Nokia O2 UK RANKPI RRM overview Features LHONRTTrafficBaseLoad = 10

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C0 (0)=(1)

C 1 (0)=(1,1)

C1 (1)=(1,-1)

C2(0)=(1,1,1,1)

C 2 (1)=(1,1,-1,-1)

C2 (2)=(1,-1,1,-1)

C2 (3)=(1,-1,-1,1)

C3 (0)=()C3 (1)=()C3 (2)=()C3 (3)=()C3 (4)=()C3 (5)=()C3 (6)=()C3 (7)=()

Code Order 0 (SF 1)

Code Order 1 (SF 2)

Code Order 2 (SF 4)

Code Order 3 (SF 8)

Downlink Spreading Codes are lacking in a WCDMA cell

ReservationRateSC(SF128) = ReservedSC

NumbAvailableSC100 *

ReservationRate(SF128) > LHOCResRateSCRange and Step: [0..100%] , 1%Default value: 80%

RNC checks based on RRI interval:


Shortage of HW resources: WBTS WSP capacity, IuB AAL2, RLC/MAC, DSP

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IuB AAL2 capacityWSP capacity RLC/MAC, DSP

> LHOHardBlockingRatioNumberOfSamplesHardBlocking

(AllSamplesHWhuntDuringMeasPeriod + LHOHardBlockingBaseLoad)100 *

Range and Step: [0..100%] , 1%Default value: 50%

Note: HW or logical resource reservation rate can be detected only when congestion is faced. A load-based handover state is triggered due to HW or logical resource congestion in the cell when a quotient of the number of samples indicating cell specific hard blocking and all samples added with the base load during the measurement period exceeds the threshold.

Processing of measurement results indicating load Load based Handover state for any cell is triggered if load exceeds load thresholds Each load trigger reason can be switched on or off separately; one reason triggered is enough

to put the cell in Load based Handover state; state is over if all trigger reasons are below threshold

t

1. Sliding window to average measurement samples when starting

load based HO state

Load based HO state triggers ON

Load based HO state "ON" indication shall be broadcasted in this point

2. Hysteresis time

Load based HOs are started if load (measured in the window 1.) rises above the threshold and stays there for the hysteresis time

3. Sliding window to average measurement samples when stopping load based HO state

Load HOs

Activation of new load basedHOs stopped

4. Timer which delays broadcasting of load based HO

state "OFF" indication

Load based HO state "OFF" indication shall be broadcasted in this point

Load based HO state triggers OFF

1.2.

3.

1.3.

4.

3.

In Load based Handover state, RNC runs RRC (UE) selection process for off-loading WCDMA cell Averaging period for starting Load based Handover state is longer than for stopping

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Load based handoverLoad based handover Service based handoverService based handover

1. connections which SRNC is this RNC 1. connections which SRNC is this RNC 1. connections which SRNC is this RNC 1. connections which SRNC is this RNC

2. connections which are not yet performing handover measurements




3. connections without previous service based handover attempts in this cell within a certain period

3. connections without previous service based handover attempts in this cell within a certain period

3. connections without previous load based handover attempts in this cellwithin a certain period

3. connections without previous load based handover attempts in this cellwithin a certain period

4. Multiservice connections without contradictions in the service priority definitions (target system can not be GSM/GPRS for CS+PS)


4. NRT connections which allocation has lasted longer than the specified period- LHOminNrtDchAllocTime (RNC)

4. NRT connections which allocation has lasted longer than the specified period- LHOminNrtDchAllocTime (RNC)



6. connections which are not in preferred RAT or WCDMA hierarcial cell layer


7. connections which cause highest load in the cell

7. connections which cause highest load in the cell

8. connections which does not require compressed mode


9. Free selection9. Free selection



7. Free selection7. Free selection



Selection of RRC connections for load and service based HO

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Special case: pure NRT traffic bearer To avoid unnecessary load based HO attempts for NRT services, packet

service must be in Cell_DCH state for a given time otherwise NRT LHO is not possible.

Only connections in Cell_DCH can be subject for LHO.

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URA_PCH

CELL_DCH CELL_FACH

CELL_PCH

UTRA RRC Connected Mode

Idle Mode

URA_PCH

CELL_DCH CELL_FACH

CELL_PCHRNC: LHOMinNrtAllocTime

Range: 1 .. 60 sec, Step 1secDefault: 20 sec

Execution of Service and Load based HOPlease note: NCHO stands for Non-Critical Handover like Service based or Load based Handovers

Specific CPICH EcNo and CPICH RSCP can be set for Service and/or Load based HO:The parameter determines the minimum level required of CPICH Ec/No (RSCP) that the

average measurement result of the best inter-frequency neighbour cell must exceed before the non-critical reason inter-frequency handover

is possible. Non-critical handovers are, for example, service and UE capability type handovers. Service and load based handover make use of this parameter.

AdjiMinEcNoNCHO / AdjiMinRscpNCHORange and Step: -24..o dB, step 0.5 / Range and Step: -115..-25 dBm,

step 0.5Default: -14 dB Default: -95 dBm

WCDMA f1

WCDMA f2

loaded layer

free layer

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In case a attempt e.g. to GSM is not successful (no resources in BSS), RNC removestarget cell from neighbor list for a while and (after new trigger) let measure the UEnew, modified GSM neighbor list:

WCDMA f1

GSM GSM

2nd best cell is tried next

AdjgPenaltyTimeNCHO (inter RAT case)AdjiPenaltyTimeNCHO (inter-frequency case)

Range and Step: 0..60 sec, step 1secDefault: 10 sec

best cell

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Thank You !

Nokia WCDMA Rel99 Packet SchedulerNokia Packet SchedulerNokia Packet SchedulerExisting Parameter splitExisting Parameter splitUplink Link AdaptationUplink link adaptation supported since RAN1.5Dynamic Link OptimisationDynamic Link Optimisation for NRT servicesDynamic Link Optimisation for NRT servicesDynamic Link Optimisation for NRT servicesDynamic Link Optimisation for NRT servicesExample DyLO scheme 1: PtxDLabsMax 50 dBm, PtxTotalMax 43dBmExample DyLO scheme 2: PtxDLabsMax 38 dBm, PtxTotalMax 43dBmOverload ControlCapacity Areas in UTRANOverload Control Methods TFCC method in UplinkOverload Control Methods TFCC method in DLCapacity Areas in UTRANEnhanced Overload ControlEnhanced Overload Control (1/3)Enhanced Overload Control (2/3)Enhanced Overload Control (3/3)Capacity Areas in UTRANEnhanced Priority Based SchedulingEnhanced Priority Based SchedulingEnhanced Priority Based SchedulingEnhanced Priority Based Scheduling- example -EPBS ParametersRT over NRT pre-emptionThroughput based optimisation of Packet Scheduler algorithmsThroughput based optimisation of PS algorithmThroughput based optimisation of PS algorithmThroughput based optimisation of PS algorithmThroughput based optimisation of PS algorithmThroughput based optimisation of PS algorithmThroughput based optimisation of PS algorithmThroughput based optimisation of PS algorithmThroughput based optimisation of PS algorithmThroughput based optimisation of Packet Scheduler algorithmsTestcase: Throughput Based Optimisation offTestcase: Throughput Based Optimisation onTestcase: Throughput Based Optimisation onTestcase: Throughput Based Optimisation onRB distribution with different test casesThroughput based optimisation of PS algorithmHow downgrading Bitrates can be analysed with countersM1005 Dedicated NBAP procedureChanging user bitrates with RL ReconfigurationFlexible upgrade of the NRT DCH data rateFlexible Upgrade for NRT DCH BitratesFlexible Upgrade for NRT DCH BitratesFlexible Upgrade for NRT DCH BitratesFlexible Upgrade for NRT DCH BitratesFlexible Upgrade for NRT DCH BitratesFlexible Upgrade of NRT DCH data rateLoad and Service based HandoverSpecial case: pure NRT traffic bearerThank You !

01 Rankpi o2 Uk Rrm Features

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