WCDMA Analysis Guideline

WCDMA Analysis WCDMA Analysis GuidelineGuideline

Shenzhen ZTE Project15-July-2009

IntroductionIntroductionThis guild line aims at helping new

engineers to identify the root of the problems. The engineer should have some basic on UMTS and familiar with ZTE CNA in order to follow this guide line.

Mobile Originate CS Call SetupMobile Originate CS Call Setup

Mobile Originate CS Call Setup :con’tMobile Originate CS Call Setup :con’t

Mobile Originating CS Call releaseMobile Originating CS Call release

Mobile originating PDP Context Mobile originating PDP Context ActivationActivation

Mobile originating PDP Context Mobile originating PDP Context DeactivationDeactivation

Identify CS CAF problem : exampleIdentify CS CAF problem : example

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No RB reconfiguration from nodeB

No Active Set update from nodeB

Ue switch to idle, no DL “connect” -> CAF

Identify abnormal CAD problem : Identify abnormal CAD problem : example example

Ue switch to idle, no UL ”disconnect” -> CAD

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MAJOR GROUP : RFMAJOR GROUP : RF

Drive Test Problem Cause code Matrix

RF : “Cross Feeder”RF : “Cross Feeder” Cross sector problem can be quickly identify from best server map using

Nemo Analyzer Run cell footprint map (RSCP) of each sector Check site location , map terrain and coverage prediction( if available) to

confirm. This to confirm that problem not due to blocking and reflecting signal

1. Check Best Server Map => Suspect !!

2. Run Cell foot print of 3 sectors3. Check with Coverage prediction (if available)4. Check site location, map& terrain

sector1 sector2

sector3

Best server plot

RF : Late Cell ReselectionRF : Late Cell Reselection

1. This case shows that Ue is moving from SC 221 to direction of SC298 in idle mode2. Call was setup at SC221 where the radio condition is degrading instead of set up call at

SC298, late reselection from SC221 to SC298 when in idle mode => CAF NOK3. Check measurement 5s before/after event = > confirm Ue camp on SC298 after event 4. Identify matrix cause => RF cause => “Late Cell Reselection”

Note : idle mode parameters detail can be found in basic feature description document, Qoffset2n.

1. CAF : not complete call setup message

2. Best SC active set RF threshold -> Fail

3. SC monitor set RF threshold -> Pass

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RF : Miss NeighborRF : Miss Neighbor

1. To identify missing adjacency , the missing adjacency RF Condition threshold is setup. 2. Check measurement about 5 seconds before event , if the threshold valid during this time3. Check measurement about 5 seconds after event. Check which sector Ue camp on.3. Check latest parameter compare with drive test date. Problem could be due to operational/error on test date , not real missing

Note: threshold guild line for quickly identify, not necessary to be rule . The analysis need also engineer field experience


3. Detected SC missing adj. Threshold -> Pass

4. Check map if missing adj. in 1st and 2nd ring from active SC -> Yes

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1. Identify abnormal CAD

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RF : OvershootingRF : Overshootingpb area& serving cell

overshooting cell

2.SC active set RF threshold -> Fail

3. detected set in window range

1. Abnormal CAD : received RRC connection release cause “unspecified”

4. Bad DL BLER

1. This case shows similar RF condition to missing adjacency criteria2. From map , it show problem area is near to serving cell, while detected set SC148, SC316 is shooting from behind of active set cell3. Run cell foot print from Nemo analyzer to confirm detected set overshooting coverage4. Check physical antenna configuration if tilting is possible5. Identify matrix cause => RF => “Overshooting” ( overshooting where the fix is down tilt to control the spill of the signal)

RF : Poor CoverageRF : Poor Coverage


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2. RF Threshold => NOK for all: active , monitor and detected set

3. Dedicated & UL Power Threshold => NOK

4. Planned site in area ?2

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1. This call shows limited of coverage in the area : - None of dl signal is higher than poor coverage threshold, dl dedicated BLER > 1% ( dl limited)

- Ue transmit max power ( uplink limited)2. Check if any planned site in this area ? 3. Identify matrix cause => RF cause => “Poor Coverage”

Note : in case of coverage limited both RSCP and EcIo always below threshold, identify cause as poor-RSCP instead of poor-Ec/Io is better way to represent coverage limited

RF : Slow HORF : Slow HO

1. This case shows that Ue is moving from SC 241 to direction of SC152 in dedicated mode2. Call was setup at SC221 where the radio condition is dramatically degrading where

handover from cell SC241 to SC152 which is not fast enough => CAD NOK3. Check measurement 5s before/after event = > confirm Ue camp on SC152 after event 4. Identify matrix cause => RF cause => “Slow HO”5. Suggest to adjust CIO between the two cell to decrease the HO time taken.Note : dedicated mode HO parameters detail can be found in basic feature description

document

1. CAD : AS signal sudden degraded dramatically


3. SC monitor set RF threshold -> Pass

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MAJOR GROUP : MAJOR GROUP : IUR / CORE / NODE-B / OTHERIUR / CORE / NODE-B / OTHER

Drive Test Cause Matrix

Core : PDP-DeactivationCore : PDP-Deactivation

1. Identify abnormal PAD

2. RF condition threshold->Pass

1. This case Ue receive downlink “deactivate PDP Context request”- check deactivation cause “Reactivation required”- check file transfer not yet complete ( transferring 2.6M of 5M)

2. This case is clearly seen the connection close request by core network but RF condition check is to confirm not related problem with RF cause

3. Identify matrix cause => non-RF => group core => “ PDP-Deactivation”-> need to check signal trace to sort out the reason for PDP deactivation.

NodeB : “UL-AlarmNodeB”NodeB : “UL-AlarmNodeB”

1. Check RF measurement 5 s before and after event. This case shows quality degrade then drop due to no active set update received

2. Check uplink RF threshold. Ue sent max transmit power when camp on SC171 => NOK 3. Check NodeB alarm &supervision = > RETU&ASC alarm => NOK4. Check pmAverageRssi report = > NOK ( < -106 dBm)5. Identify matrix cause => non-RF => nodeB alarm => nodeB cause => “UL-

AlarmNodeB”


2. Active set DL RF threshold => NOK

5. UL RF threshold => Problem

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3. Monitor RF threshold => OK4. Check if UE send MR e1a this SC => OK

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Other: Oth-PLMNOther: Oth-PLMN

1. Nemo identify this case as PS RUF “Protocol error unspecified” -> routing area update failure

2. Check RRC/L3 message - Ue request LAU /RAU to network , network reject LAU with cause “no suitable cell in LA”- Network reject RAU with “Protocol error unspecified” , consequence of LAU reject- Check RRC “Master_Information_Block” -> Ue report PLMN= “50219” -> other PLMN network

3. Check Layer1 report show Ue camp on UARFCN = 10762 - > confirm other PLMN network4. Identify matrix cause => non-RF => Other => Oth-PLMN

1. Ue read master_Info_blck -> PLMN “50219”

2. LAU/ RAU request

3. LAU/ RAU reject

4. Layer1 report AC UARFCN=10762

MAJOR GROUP : MAJOR GROUP : TOOL / UTRAN / TOOL / UTRAN / UNKNOWNUNKNOWN

Drive Test Problem Cause Matrix

Tool : DT-FailTool : DT-Fail

1. Nemo identify this case as CAF : Test System Failure 2. Check time from last RRC/L3 dedicated channel to idle channel -> 5 minutes different3. Check Layer1 report during that 5 minutes different -> Layer1 data freeze 4. Identify matrix cause => non-RF => Tool cause => “DT-Fail”

1. Identify CAF

2. Check layer1 report during gap timer

Tool : “DT-User”Tool : “DT-User”

1. Nemo identify this case as CAF : Timeout before connection due to missing of Radio Bearer setup2. Check establishment cause RRC connection request => originatingConversationalCall ? NOK 3. This case show that the Ue receive SMS during drive test : RRC connection request establishment cause “terminatingLowPrioritySignalling” 4. Identify matrix cause => non-RF => Tool cause => code “DT-User”

1. Check RRC/L3 messages, Identify CAF

Ue receiving SMS

UTRAN : BLCKUTRAN : BLCK

1. Check RRC/L3 message : Ue received DL NAS “Disconnect” during call set up -> CAF NOK!!- check disconnect cause -> “No circuit/channel available”

2. Check “pmNoReqDeniedAdm” & “pmNoFailRabEstAtt_xx” counter during drive test problem3. Indentify matrix cause => UTRAN => BLCK (call return as congestion or no channel available)

Note: pm procedure is reference in “U Mobile Network Statistic KPI(P5)” document

1. Check RRC/L3 messages, Identify CAF

2. No uplink

UTRAN : No-RrcUTRAN : No-Rrc

1. Check RRC/L3 message : CAF NOK!!2. Check radio condition threshold pilot and dedicated channel -> pass4. Indentify matrix cause => non-RF => UTRAN => No-Rrc

1. Identify abnormal CAF

Expected RB_reconfiguration : missing

Expected Active_set update : missing

2. DL RF Threshold -> pass

3. UL & DCH Threshold -> pass

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Unknown: DL1 Unknown: DL1

1. Check RRC/L3 message : Ue received Downlink “RRC Connection release” from network -> CAD NOK!!- check connection release cause “unspecified”

2. Check radio condition threshold pilot and dedicated channel -> pass3. Check radio condition 5s before/after event , check PM cell availability , check supervision -> pass4. Indentify matrix cause => non-RF => unknown => DL1


2. DL RF Threshold -> Pass

3. Dedicated &UL Threshold -> Pass

Unknown: Iur-1 Unknown: Iur-1

1. Check RRC/L3 message : UE received Downlink “RRC Connection release” from network -> CAD NOK!!- check connection release cause “normal event”

2. Check radio condition threshold pilot and dedicated channel -> pass3. Check radio condition 5s before/after event , check PM cell availability , check supervision -> pass4. Indentify matrix cause => non-RF => unknown => Iur transmission error.


3. UE transmit power reached Max -> Failed

2. Radio Condition -> Pass

4. Identify area, RNC border-> suspect Iur transmission error.

Unknown: Iur-2 Unknown: Iur-2

1. Check RRC/L3 message : UE received Downlink “RRC Connection release” from network -> CAD NOK!!- check connection release cause “normal event”

2. Check radio condition threshold pilot and dedicated channel -> pass3. Check radio condition 5s before/after event , check PM cell availability , check supervision -> pass4. Indentify matrix cause => non-RF => unknown => Iur transmission error.


3. UE transmit power reached Max -> Failed

2. Radio Condition -> Pass

4. Identify area, RNC border-> suspect Iur transmission error.

The EndThe End

WCDMA Analysis Guideline

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