p5 impact on kpis - o2

P5 impact on KPIs

Dublin19th June 2007

Luca Lunardi

Senior RF ConsultantEricsson GSDC, Italy

P5 impact on KPIsIntroductionP5 updates

HSDPAEULChannel SwitchingURA stateNew UeRcs

P5 impact on KPIsAccessibilityRetainabilityIntegrityMobilityTraffic & CapacityAvailability

Introduction - UTRAN observabilityObservability covers all functions in UTRAN to monitor and analyze

performance and characteristics of UTRAN system. This can be doneon various levels with different target groups and requirements.

KPIs represent end-user perceptionof a network on a macro level

PIs represent information on a system level indicating system performance

Procedure level represents deeper troubleshooting and measure system characteristics measurements

HSDPA - Code Multiplexing

Share the HS-DSCH resource among max 4 users in the code domainAvailable resources (codes and power) are sequentially assigned to the selected user(s) At the beginning of scheduling procedure all available codes and power resources are offered to the first selected userNext user can take only the remaining resources after transport format selection of previous user.This procedure will be repeated until there are no remaining resources left. 1 HS-SCCH per user, power controlled between a minimum and a maximum value

TTI=2msUser 1

User 2

Dynamic Code Allocation

Common Channels

Min - HS-PDSCH

DCH Load dependent Flexible increase

DCH

DCH

HS-DSCH

A minimum number of codes can be set If there are available codes, RBS can expand the number of HS-PDSCH

Shared Channel transmission

Channelization codes allocated

for HS-DSCH transmission9 codes (example)

SF=16

SF=8

SF=4

SF=2

SF=1

User #1 User #2 User #3 User #4

TTI

Fixed (min) amount of allocated channelization codes

time

Dynamically allocatedchannelization codes

HSDPA transitionsIn P4 the HSDPA RB is treated as a ”RAB”

Always set up on HS if capableAlways release RAB to idle when InactiveDrop when HS coverage is lost

In P5 the HSDPA RB is not treated as a RAB!Possible to switch back and forth between HS and DCH/ FACHNormal Release ”always” on R99

HS

Idle

EUL RAB/RB aspects in P5One PS Interactive EUL/HS RAB Max bitrate (RLC): RB=1.376 Mbps; SRB UL=13.6 kbpsOne RB combination (UeRc) with EUL

UL: E-DCH for RB and SRBDL: DCH for SRB (3.4 kbps same as for r’99 DCH in DL)DL: HS-DSCH for RB (same as DCH/HS)

Inactivity supervision when on EUL/HSdownswitch to Cell_FACH

Fallback to r’99 for RAB combinations (e.g.SP64, PS+PS)Reconfiguration to r’99 DCH/DCH or DCH/HS

loss of coverage or bad qualityNo multiRABNo EUL over IurNo compressed mode -> no IFHO, no IRAT HO

EUL channel structure

E-AGCH

Serving EUL cell

E-DPDCH

E-DPCCH

Non serving EUL cell

E-RGCH

E-DPDCH

E-DPCCH

E-HICHE-HICH

E-DCH

E-DCH

New Physical Channels:E-AGCH Enhanced Absolute Grant Channel

E-RGCH Enhanced Relative Grant Channel

E-HICH HARQ Indicator Channel

E-DPDCH Enhanced Dedicated Physical Data Channel

E-DPCCH Enhanced Dedicated Physical Control Channel

New Transport Channel:E-DCH Enhanced Dedicated Channel

Additional Physical Channel used for EUL:DPCCH (R99) Dedicated Physical Control Channel

DPCCHDPCCH

E-DPDCH

EUL overview - Architecture

RNC

RBS

UE

Scheduler

Uu load estimation

Iub flow control

HW allocation

Outer loop power control

Reordering

Capacity management

Iub congestion

HARQ retransmissionsRate

request

Mobility

HARQ

Scheduler responsibility

RBS

SchedulerIub

resources for all cells served by RBS

Cell AUu

interface resources (e.g. load)

Cell BUu


Cell CUu


HW (CE) resources for all cells served by RBS

Scheduler interactions

Scheduling: check on HW, Iub & UL Noise Raise

Total pool size DCH

EUL scheduling limit

Scheduler

E-DCH

UL Noise Rise

UL Iub capacity

UL CE

”X dB” ”Y Mbps” ”Z CE”

0

Scheduling: Uu load estimatorUu load estimator provides the Scheduler with updates of the available air interface

load. eulMaxOwnUuLoad is the limit for own-cell interference (default =3 dB)eulMaxRoTCoverage is the limit for the total tolerated interference (default = 10 dB)

Scheduling: Interference

UE TX power granted by RBSBit rate adjusted based on difference between granted power and Rel 5 power

t

Max allowed interferenceUL

interference

R5 DCH

E-DCH MAC-e Rate selection User 2

E-DCH MAC-e Rate selection User 1

EUL - reschedulingRescheduling may take place if:

An E-DCH user requests higher ratesA new E-DCH user enters the cell when resources are fully used

The user with a higher scheduled grant “gives” some of its resources to the user with the lower scheduled grant EUL scheduler tries to give the users targeted for rescheduling, a target rate at least = eulTargetRate

MAC-e HARQ ProtocolPDU is put into one of several HARQ processes in the MAC-e HARQ protocol.

The MAC-e HARQ ensures that retransmissions due to packet loss over the air interface are performed more efficiently and with a much lower round-trip-time.

Mac e/es demultiplexingSRB carrying RRC data is mapped to E-DCH in the uplink (non-scheduled data)PS Interactive data scheduledOne E-DCH transport channel with two MAC-d flows.

SRB multiplexed into one MAC-d flow PS Interactive is mapped to the second MAC-d flow. This allows for scheduled and non-scheduled transmission on the different flows (different Iub transport bearer)SRB PS

Interactive

Channel Switching

Switching between– FACH and EUL/HSDPA– FACH and DCH/HSDPA

And switching– DCH to EUL/HSDPA– DCH to DCH/HSDPA– DCH/HSDPA to EUL/HSDPA

Multi RAB follows same principlesBenefits:

Efficient use of bandwidthEnhanced soft congestion functionality

PS RAB establishment Poor Quality for EUL channelsCS RAB establishment HS is reconfigured to DCH (any HS trigger)UL and/or DL throughput threshold Low throughput (including user inactivity)UL and/or DL throughput threshold Normal: Iu connection release (CN initiated)PS RAB release Congestion triggered HS -> Cell_FACH(normal CN initiated RAB release) Exceptional: UTRAN generated Iu releaseCoverage of EUL ceases, HS remains (e.g. UE connection lost)

EUL/HSPS Interactive (1 RAB)

DCH/DCH PS Interactive (1 RAB)

DCH/HSPS Interactive (1 RAB)

Idle

Cell_FACHPS Interactive (1 RAB)SRB_DCH

(no RAB)

DCH/HSPS Int + speech

DCH/DCHPS Int + speech (SP64 or

SP0)1

2

3

4

6

7

8

9

10

11

12

2

2

3 3

45

67 8

9 11

5

r’99 RAB combination (service triggered fallback to r’99)

Reject RAB est.

RAB release

1

12

1012

21

State transitions

Description:– A URA is an area consisting of one or a number of cells.– URA_PCH state is a mode "in-between" common CELL_FACH and idle mode.– In URA_PCH state the RAB and CN signalling connection is kept but the UE has no radio resources.

Benefits:– reduced service re-activation time for interactive packetusers compared to from idle mode– reduced signaling towards the RNC and the CNin connected mode

URA state

New UeRcs

Many new UeRcs available in P5, particularly:

EULSpeech + HS MultiRABs

Iu Signaling connection...New counters available to monitor Iu-CS and Iu-PS Signaling connectionsNew accessibility formulas:

... and load sharing (1/2)New counters to monitor load sharing events for CS and PSUpdated formulas: RRC Setup Success Rate CS and PS

Updated formula: Overall Accessibility Speech

... and load sharing (2/2)Updated formulas: Overall Accessibility CS Data, PS Stream, PS Interactive

Load sharingNew IFLS formula, splitted for CS and PS

Emergency callNew counters to monitor Emergency call establishment and successUpdated formula: RAB Est Succ Rate Emergency call, RAB Establishment SR Overall

Admission Control - RRCNew counters to monitor RRC Connection denied by Admission ControlNew formulas: RRC Failure due to Admission (total, CS, PS), RRC Failure after Admission

Admission Control – HW failureNew counters to monitor failed RAB establishment attempts due to lack of hardware resourcesNew formulas: RAB Failure DL/UL Hw

Admission Control – HW failureNew/updated formulas to take UL/DL HW resource monitorBlocking due to lack of SF

Blocking due to DL Hardware limit

Paging & Terminating callsNew counters available to distinguish Paging type 1 for CS and PS (added in P 4.0.16)

New counters available to monitor Terminated calls (added in P 4.0.16)

Accessibility EUL

Number of E-DCH users having cell as serving cell

eulServingCellUsersAdm

Request for E-DCH having cell as serving cell Resources admitted

Number of E-DCH users in Soft/Softer HOhaving cell as non-serving cell

eulNonServingCellUsersAdm

Request for E-DCH having cell as non-serving cellResources admitted

Serving cell E-DCH users are limited by eulServingCellUsersAdm (default 32)Non-serving cell E-DCH users limited by eulNonServingCellUsersAdm (def. 100)

Admission rejects E-DCH users requesting the cell as serving cell because of too many serving cell EUL users:

Admission rejects E-DCH users requesting the cell as non-serving cell: too many non-serving cell EUL users:

Accessibility EULNew counters and formula introduced to monitor EUL (HSUPA) accessibility

Number of admission requests denied at RAB establishment on E-DCH

Retainability PS Interactive

In case of URA state introduction, PS drop has to be updated

New recommended formula is PS Interactive Minutes per Drop

Retainability PS InteractivePS Interactive MBytes/drop

DL traffic

UL traffic, including EUL

Retainability HSDPAHSDPA drop P5 vs P4

HS drop is not comparable in P5 with P4HS drop formula from P4 shouldn’t be used

HS minutes Per DropHS Min/Drop is more relevant to be used specially for comparison with P4

Retainability HSDPACounters pmNoOfTermHsCong and pmInactivityHsIdle have been removed. In case congestion control is triggered for HSDPA connection, or in case of user inactivity, an HSDPA->FACH reconfiguration is attempted.

Retainability EULSuggested formula for EUL retainability is in minutes per drop:

RAB holding timeNew formulas added in BO to monitor RAB holding time

Retainability SpeechNew formulas added in BO to distinguish speech drops categories

DCR Speech distribution

1

2

3

4

5

6

1

2

3

4

5

6

Iur related formulasNew formulas added in BO to count for drops over Iur:

RAB drop ratesMinutes per drop

PS R99 Ch. SwitchingNew counters and formulas to monitor channel switching transitions PS R99

LOW RATE

MEDIUM RATE

HIGH RATE

HSPA � DCH & HSPA � FACH New counters and formulas to monitor HSPA � DCH and HSPA � FACH reconfigurations

DL upswitch:DCH to HS & FACH to HS

UL upswitch:DCH to EUL & FACH to EUL

DL downswitch:HS to DCH

UL downswitch:EUL to DCH

HSPA � FACHNumber of FACH � HSPA reconfigurations due to user increased activity

Number of Radio Connections including HSDPA, channel downswitched

due to congestion action:

Number of E-DCH users downswitched due to DL congestion (either

EUL serving cell or EUL non-serving cell):

DL upswitch:FACH to HS

DL downswitch:EUL/HS to FACH

UL downswitch:EUL/HS to FACH

HSDPA throughputChanged unit in P5 for the following counters:

pmSumAckedBits (unit 1000 bits; was bits in P4)pmSumTransmittedBits (unit 1000 bits; was bits in P4)

EUL throughputEUL throughput

Granted Uu rate (PDF)

MAC-e efficiency

Total granted Uu rate for all E-DCH users per cell (including SOHO). Updated every 100 msPDF with 100 kbit/s resolution in range [0..6000].pmTotRateGrantedEul [0]: number of samples in range [0..100[pmTotRateGrantedEul [1]: number of samples in range [100..200[…pmTotRateGrantedEul [59]: number of samples in range [5900..6000[pmTotRateGrantedEul [60]: samples greater than or equal to 6000

EUL integrityNumber of events when HARQ failure is indicated for the PS Int and SRBs

MAC-es PDU delivery Failure Rate

EUL HARQ Retransmission rate PS

PS interactive throughputPS interactive DL User Throughput (all PS Int. RABs, no retransmission)

PS interactive UL User Throughput (all PS Int. RABs, no retransmission)

PS interactive DL User Throughput (all PS Int. RABs, with retransmission)

PS interactive UL User Throughput (all PS Int. RABs, with retransmission)

MobilityIRAT CC success

EUL Cell Change

Number of Radio Link setup or Radio Link addition requests denied byadmission control. The counter is triggered when an RL Setup Request or RL Addition Request is denied by Admission Control for either Soft and Softer Handover

pmNoRlDeniedAdm

Cell level traffic (1/3)The following counters are not stepped in P5:

pmSumBestCs12PsIntRabEstablishpmSumBestCs64PsIntRabEstablish

Counter pmSumCs12RabEstablish changed to include CS 12 traffic within Multi-RAB combinations with Speech 12.2 Updated formulas for traffic at cell level (e.g. speech, Cs Data)

New formula for EUL traffic at cell level

Cell level traffic (2/3)The following counters have been removed in P5:

pmDlTrafficVolumeCs12Ps0pmDlTrafficVolumeCs12Ps64pmDlTrafficVolumeCs64Ps8pmDlTrafficVolumePsStr128Ps8pmDlTrafficVolumePsStr64Ps8

New counters introduced to monitor traffic level:pmDlTrafficVolumePs8pmDlTrafficVolumePsStr128pmDlTrafficVolumePsStr16pmDlTrafficVolumePsStr64

Cell level traffic (3/3)Updated formulas for traffic at cell level:

RNC level traffic (1/5)New UeRc available in P5 and updated/new RNC level traffic (Erlang)

RNC level traffic (2/5)New UeRcs available in P5, modifying RNC level traffic (Erlang)

RNC level traffic (3/5)New UeRcs available in P5, modifying RNC level traffic volumes (GB)

RNC level traffic (4/5)New UeRcs available in P5, modifying RNC level traffic volumes (GB)

RNC level traffic (5/5)New UeRcs available in P5, modifying RNC level traffic volume

Traffic Soft Handover Overhead (1/2)The following counters have been removed:

- pmSumPs64RabEstablishpmSumPs128RabEstablishpmSumPs384RabEstablish

The following counters are not stepped in P5:pmSumCs64Ps8RabEstablishpmSumCs12Ps0RabEstablish pmSumCs12Ps64RabEstablish

New counter introduced for PS Interactive:pmSumPsInteractive

Traffic Soft Handover Overhead (2/2)Updated formulas to evaluate Traffic SHO overhead:

Dynamic code all. & Code multiplexingAverage number of codes added because of Dynamic Code Allocation

Limitation of dynamic code allocation due to hardware shortage. RBS HW addition should be beneficial

Number of users scheduled per TTI (PDF)

Reason for not scheduling another HSDPA user for immediate traffic

HSPA Iub capacityIub Capacity limiting ratio HSDPA

Iub Capacity limiting ratio EUL

Note: Iub Capacity limitation does not necessarily implies Iub is thebottleneck of HSPA performance. Other indicators can be used, e.g.:

E-DCH Iub bit rate sent by the RBS in uplink over Iub:

Target HS bit rate, percentage of maxHsRate :Iub frame lost detection:

EUL schedulingNum. of scheduling decisions to increase the Iub rate of an E-DCH user decreasing the Iub rate for another E-DCH user due to UL Iub resource limitations

Num. of scheduling decisions to increase the HW rate of an E-DCH user decreasing the HW rate for another E-DCH user due to UL HW resource limitations

Num. of scheduling decisions to increase the Uu rate of an E-DCH user decreasing the Uu rate for another E-DCH user due to UL Uu load limitations

CE limitation

TN limitation

Load limitation Uu

Number of times that no E-DCH traffic is allowed due to UL interference

UL interference

UL InterferenceNew resolution and average calculation for the counter pmAverageRssi

Measured every 100 ms; the average value is calculated every 100 ms (1 sec in P4). 0.5 dB resolution for the first 61 values and range [-110.0..-80.0], followed by a range [-80..-65] with a 5 db resolution.averageRssi[0] number of sampled values < -110.0averageRssi[1] number of sampled values in range [-110.0..-109.5[averageRssi[2] number of sampled values in range [-109.5..-109.0[averageRssi[3] number of sampled values in range [-109.0..-108.5[...averageRssi[59] number of sampled values in range [-81.0..-80.5[averageRssi[60] number of sampled values in range [-80.5..-80.0[averageRssi[61] number of sampled values in range [-80.0..-75.0[averageRssi[62] number of sampled values in range [-75.0..-70.0[averageRssi[63] number of sampled values in range [-70.0..-65.0[averageRssi[64] number of sampled values ≥ -65.0

Tx Carrier Power / non HSNew resolution and average calculation for the counters pmTransmittedCarrierPower and pmTransmittedCarrierPowerNonHs

pmTransmittedCarrierPower

Measured every 100 ms (4 sec in P4)0.5 dBm resolution and the range [25..50] except for the first and last value:pmTransmittedCarrierPower[0]: Number of sampled values < 25 dBmpmTransmittedCarrierPower[1]: Number of sampled values in range [25..25.5[ dBm… pmTransmittedCarrierPower[50]: Number of sampled values in range [49.5..50[ dBmpmTransmittedCarrierPower[51]: Number of sampled values ≥ 50 dBm

pmTransmittedCarrierPowerNonHs

Measured every 100 ms (4 sec in P4)Same resolution and ranges as for pmTransmittedCarrierPower

EUL utilizationNumber of CEs allocated on the UL HW by the E-UL scheduler

Power-controlled noise rise due to intra-cell interference affecting Uu load

Total Rise over Thermal (all UL traffic and Ext. interference) affecting coverage

Total DL power used for the E-AGCH, E-RGCH and E-HICH in the cell

Total number of simultaneous scheduled E-DCH users having a rate >0 kbit/s

AvailabilityNew counters and formulas for EUL availability

p5 impact on kpis - o2

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