ul interference

3G Optimisation Task Force 1 © NOKIA Presentation_Name.PPT / DD-MM-YYYY / Initials

3G Optimisation Task Force meeting

Milan 15-10-2004


Agenda

• Admission Control ~1, 1/2 h

• NBAP Counters ~ 1h

• Activation Time Offset~ 30 min.

• Next Activities


Vodafone Proposal• VF has decide to focus on admission control, since several failures are

detected through counters even in low traffic cells.

• Blocked call (CS domain and SRB).

• Both UL and DL Admission Control algorithms should be investigated.

• How to use NBAP counters for troubleshooting


Nokia Proposal for Admission Control• The troubleshooting activities are based in Italy and France

• Achieved results will be used in other OpCos

• The task is splitted in 4 phases:

• 1 Performance Assessment : in order to understand impact of AC blocking on overall network performance and identify worst performing cell (possible benchmarking between OpCos)

• 2 Troubleshooting in order to find out reasons for AC blocking (high cell traffic load, high other cell interference, high background noise, UL or DL blocking) and correlate counters with network events.

• 3 Parameter Assessment: identifying most important parameters and their impact on Admission Control (parameter benchmarking between OpCos)

• 4 Optimisation Plan depending on the failure scenarios:• Parameter change• Specific field test


Agenda• 1 Performance Assessment : in order to understand impact of AC

blocking on overall network performance and identify worst performing cell (possible benchmarking between OpCos)





• Example: RAB Establishment Failure Cause (all VF It network)• Still a high share of admission control and other causes (typically on the equipment side)

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RAB VOICE SETUP FAILURE AC RAB VOICE SETUP FAILURE BTS RAB VOICE SETUP FAILURE TRANS

RAB VOICE SETUP FAILURE RNC RAB VOICE ACCESS FAILURE MS RAB VOICE ACCESS FAILURE RNC

Main failure cause is in the access phase, typically for radio reasons

Still a high % of failure in the set up phase due to admission control and other issues (equipment)

VF Italy-PLMN


Distribution of RRC failures for Milan• 99% of the failures volume come from less than 1% of the cells.

• Due to RRC Connection Request repetitions one cell can show thousands of failures Nb of cells causing AC failures

80%

82%

84%

86%

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Nb of cells within cluster

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SFR - Paris

WS OPTIM IDF

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RADIO_CONGESTION_FAILURES

RADIO_COVERAGE_SETUP_FAILURES

RADIO_COVERAGE_ACTIVE_FAILURES

IUB_TRANS_FAILURES

BTS_HW_FAILURES

RNC_HW_FAILURES

CORE_OR_IUR_FAILURES

CALL FAILURES by Causes - WS OPTIM IDF

147251 213 210 145 88

182 252 267 337241 194 135 152

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RADIO_COVERAGE_ACTIVE_FAILURES RADIO_COVERAGE_SETUP_FAILURESRADIO_CONGESTION_FAILURES IUB_TRANS_FAILURESBTS_HW_FAILURES RNC_HW_FAILURESCORE_OR_IUR_FAILURES RRC Connection Setup Attempt


Distribution of RRC Failures in Paris• 3 cells (0.3% of all cluster) cause 84% of AC failures

• 10 cells (1.1% of all cluster) cause 95% of AC failures

Nb of cells causing AC failures

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Agenda


Introduction• Purpose of the troubleshooting activity was to find out the reasons

leading to an high number of setup failures due to Admission Control.

• Troubleshooting has been focused on Vodafone Italy network in Milan during week 30 and week 31.

• Additional measurements have been collected during weeks 38-40 in Milan

• Vodafone Italy Admission Control parameters:

• UL AC:• PrxTarget = 4 dB• PrxOffset = 1 dB

• DL AC:• PtxTarget = 37 (8 W), 41 dBm (20 W), 43 dBm (40 W)• PtxOffset = 1 dB (20 W and 8 W), 2 dB (40 W)

• Load Control:• PrxNoiseAutotuning = true• PrxNoise = -92 dBm • PrxNoiseMaxTuneAbsolute = 0.5 dB


Setup Performance Milano RNC1• RRC Setup failures for Admission Control are generally low but July 20

• RAB Voice Setup failures for Admission Control are generally low but July 21

• RAB CS Conversational and PS Setup failures for Admission Control are negligible

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NE-RNC-2 MILANO1 20040719 868592013 19537 5 0.0% 1879 13 0.7% 295 0 0.0% 7345 0 0.0%NE-RNC-2 MILANO1 20040720 868592013 27667 2551 9.2% 2296 9 0.4% 301 0 0.0% 10158 0 0.0%NE-RNC-2 MILANO1 20040721 868592013 26470 23 0.1% 2747 50 1.8% 286 0 0.0% 9738 0 0.0%NE-RNC-2 MILANO1 20040722 868592013 26526 8 0.0% 2540 0 0.0% 300 0 0.0% 10669 0 0.0%NE-RNC-2 MILANO1 20040723 868592013 25245 1 0.0% 2292 3 0.1% 280 0 0.0% 10012 0 0.0%NE-RNC-2 MILANO1 20040724 868592013 14926 0 0.0% 1215 0 0.0% 67 0 0.0% 5555 0 0.0%NE-RNC-2 MILANO1 20040725 868592013 15030 0 0.0% 1058 0 0.0% 69 0 0.0% 5729 0 0.0%NE-RNC-2 MILANO1 20040726 868592013 24600 0 0.0% 2330 3 0.1% 102 0 0.0% 9940 0 0.0%


Setup Performance Milano RNC2• RRC Setup failures for Admission Control are generally low but July 26

• RAB Voice Setup failures for Admission Control are generally low but July 26

• RAB CS Conversational and PS Setup failures for Admission Control are negligible

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NE-RNC-3 MILANO2 20040719 865756013 28546 32 0.1% 3448 2 0.1% 212 0 0.0% 7679 2 0.0%NE-RNC-3 MILANO2 20040720 865756013 30044 151 0.5% 3730 6 0.2% 79 0 0.0% 8211 6 0.1%NE-RNC-3 MILANO2 20040721 865756013 29214 152 0.5% 3566 4 0.1% 98 1 1.0% 8277 5 0.1%NE-RNC-3 MILANO2 20040722 865756013 32212 54 0.2% 3929 2 0.1% 150 0 0.0% 9305 0 0.0%NE-RNC-3 MILANO2 20040723 865756013 30390 54 0.2% 3323 3 0.1% 82 0 0.0% 8815 1 0.0%NE-RNC-3 MILANO2 20040724 865756013 19327 0 0.0% 1240 3 0.2% 48 0 0.0% 5831 0 0.0%NE-RNC-3 MILANO2 20040725 865756013 16468 0 0.0% 924 0 0.0% 31 0 0.0% 4604 0 0.0%NE-RNC-3 MILANO2 20040726 865756013 46028 19143 41.6% 2866 30 1.0% 89 0 0.0% 7724 6 0.1%


Root cause for RRC AC failures• When cross-checking the Cell Resource indicators for the cells with

failures three causes are identified:• UL Interference (High PrxTot Class 0, PrxNoise): Biggest cause• Cell availability: Second cause• High LPA signal Alarm causing DL failures: Negligible

RRC "Admission Control" Failure root cause

88%

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InterferenceLPA AlarmCell availability

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NE-RNC-3 61691 MILANO2 33689 18514 55.0% InterferenceNE-RNC-2 63331 MILANO1 2828 2542 89.9% Cell AvailabilityNE-RNC-3 62092 MILANO2 8950 555 6.2% InterferenceNE-RNC-3 63511 MILANO2 4936 174 3.5% InterferenceNE-RNC-3 63763 MILANO2 2990 148 4.9% InterferenceNE-RNC-3 63762 MILANO2 555 84 15.1% InterferenceNE-RNC-2 63343 MILANO1 249 27 10.8%LPA AlarmNE-RNC-3 60962 MILANO2 175 54 30.9% Cell AvailabilityNE-RNC-3 60963 MILANO2 178 35 19.7% Cell AvailabilityNE-RNC-3 63513 MILANO2 2405 19 0.8% InterferenceNE-RNC-2 62691 MILANO1 310 18 5.8% Interference


Root cause for Voice and VT RAB AC Failures

• The same classification is applied to RT RAB Setup

• Most failures come from 63343 with LPA Alarm and neighbouring cells

• Cell availability is not visible at RAB level

Voice RAB "Admission Control" Failure root cause

44%

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Interference

LPA Alarm

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NE-RNC-2 63343 MILANO1 52 52 100.0% 0 0 LPA AlarmNE-RNC-3 61691 MILANO2 3967 18 0.5% 47 0 0.0% InterferenceNE-RNC-3 62092 MILANO2 1404 9 0.6% 46 0 0.0% InterferenceNE-RNC-3 63511 MILANO2 1045 8 0.8% 65 0 0.0% InterferenceNE-RNC-2 63901 MILANO1 53 8 15.1% 1 0 0.0% LPA AlarmNE-RNC-2 63342 MILANO1 56 7 12.5% 0 0 LPA AlarmNE-RNC-2 63902 MILANO1 70 7 10.0% 7 0 0.0% LPA AlarmNE-RNC-3 63322 MILANO2 586 4 0.7% 6 0 0.0% Interference


Case 1: Cell Availability• High number of RRC failures for Admission Control does not necessary

mean high traffic or interference problem but it might reflect cell availability problem.

• Cell Availability problem is generally not reflected by RAB Setup failures because the call is blocked at the RRC phase.

• Diagnostic through counters and KPI: • High AC_RRC Setup Failure Rate : huge number of RRC attempts is an

indicator that the problems is continuous.• Traffic counters may or may not reflect the same behaviour: in some cases

the traffic counters are not incremented because the DCH request is not even received by the Admission Control.

• Average PrxTotal = PrxNoise (Average PrxTotal_excl_0 = Average PrxTotal_class_0) means very low traffic in the cell

• Cell Availability << 100%• Alarm may or may not be present DIFFICULT TO DETECT BY O&M

• Cause:• Solution:

• implement script to detect cell availability problems in advance, before performance degradation.

• cell restart might solve the problem


Case 1: Cell Availability Example• Cell 63331 shows high number of RRC Setup

Failures for Admission Control on July 20

• From Service Level counters huge number of RRC attemptsRRC repetitions due to T300 and N300:

• From Cell Resource counters:

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2574 2542 98.8%

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ILNE-RNC-2 63331 MILANO1 2004072000 -104.4 100%NE-RNC-2 63331 MILANO1 2004072001 -104.4 100%NE-RNC-2 63331 MILANO1 2004072002 -104.4 100%NE-RNC-2 63331 MILANO1 2004072003 -104.4 100%NE-RNC-2 63331 MILANO1 2004072004 -104.4 99%NE-RNC-2 63331 MILANO1 2004072005 -104.4 100%NE-RNC-2 63331 MILANO1 2004072006 -104.4 100%NE-RNC-2 63331 MILANO1 2004072007 -104.4 100%NE-RNC-2 63331 MILANO1 2004072008 -104.4 100%NE-RNC-2 63331 MILANO1 2004072009 -104.4 100%NE-RNC-2 63331 MILANO1 2004072011 -104.4 7%NE-RNC-2 63331 MILANO1 2004072012 -104.5 0%NE-RNC-2 63331 MILANO1 2004072013 -104.5 0%NE-RNC-2 63331 MILANO1 2004072014 -104.4 0%NE-RNC-2 63331 MILANO1 2004072015 -104.4 0%NE-RNC-2 63331 MILANO1 2004072016 -104.4 0%NE-RNC-2 63331 MILANO1 2004072017 -104.4 0%NE-RNC-2 63331 MILANO1 2004072018 -104.4 0%NE-RNC-2 63331 MILANO1 2004072019 -104.3 0%NE-RNC-2 63331 MILANO1 2004072020 -104.4 52%NE-RNC-2 63331 MILANO1 2004072021 -104.4 100%NE-RNC-2 63331 MILANO1 2004072022 -104.3705098 100%NE-RNC-2 63331 MILANO1 2004072023 -104.3925006 100%

Average PrxTotal shows neither traffic or interference

Cell Availability problem from 11am to 8 pm Alarm in the

cellstart

stop


Case 2: Interference• High number of RRC failures for Admission Control may be due to some external

or internal interference source, leading to an increase of the background noise.• Interference problem can be detected both by RRC setup counters and RAB

setup counters depending on the level of the interference• Diagnostic through counters and KPI:

• High AC_RRC Setup Failure Rate : huge number of RRC attempts is an indicator that the problems is continuous and the level of the interference is above PrxTarget + Offset

• High AC_RAB Setup Failure Rate : high number of AC failures is an indicator that the problems is continuous and the level of the interference is above PrxTarget.

• UL DCH Reject Rate Sign >> DL DCH Reject Rate Sign :Traffic counters generally show failure due to UL Admission Control.

• Average PrxTotal >> PrxNoise : Average PrxTotal_class_0 ~ PrxTarget+ Offset means that all the UL received power is due to interference

• Alarm is not present at all DIFFICULT TO DETECT BY O&M

• Cause: external interference or internal interference due to some mobiles transmitting power much higher than required

• Solution: • implement script to detect interference problems in advance, before

performance degradation• Let autotuning algorithm change the PrxNoise according to the maximum

variation (PrxNoiseMaxTuneAbsolute from 0.5dB to 20 dB): no effect if the cell is loaded

• If the duration of the interference is big change temporary the PrxTarget parameter according to the interference amplitude


Case 2 : Interference Example• The reason of failures was an interference

source starting between 9 and 10 am visible through the Average PrxTotal class 0 KPI.

• The interference was well above the Target + Offset (-87 dBm) threshold blocking all the RRC Connection Request for several days (temporary solution was to increase PrxTarget to 30 dB)

• The problem was solved switching off the Connect Card generating the interference

Average PrxTotal class 0

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Average PrxTotal class 0

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61691 20040726 18567 18504 99.7%61691 20040728 1044 877 84.0%61691 20040727 10345 9147 88.4%


Case 3 : LPA Alarm• RAB Setup Failure for Admission Control due to LPA failure: cell

transmitting at very high power ~ 43 dBm (PtxTarget = 43 dBm) constantly100% of failures in RAB RT Setup.

• Blocking can be seen at RRC level as well

• Diagnostic through counters and KPI:• AC_RAB Voice Setup Failure Rate ~ 100% (depending on the

parameter PtxTarget).• DL DCH Reject Rate Voice >> UL DCH Reject Rate Voice • Average PtxTotal constantly bigger than the total power of

Common Channels.• In the neighbour cells there are failures in RAB Setup for RT but no

failures in the DCH allocation from Traffic table counters.• Alarm on the cell: LPA input signal level is too high

• Cause: WTR or WPA problems

• Solution: The problem has been solved by swapping the bus cable in the back-plane.


Case 3 : LPA Alarm Example

Average PtxTotal ~ 43 dBm

PtxTarget in the cell is 43 dBm

Very easily the cell is in marginal load area blocking for RT RAB services

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NE-RNC-2 63343 MILANO1 20040719 28 5 17.9% 4 4 100.0% 0 0NE-RNC-2 63343 MILANO1 20040720 39 9 23.1% 7 7 100.0% 1 0 0.0%NE-RNC-2 63343 MILANO1 20040721 86 5 5.8% 35 35 100.0% 0 0NE-RNC-2 63343 MILANO1 20040722 46 8 17.4% 0 0 4 0 0.0%NE-RNC-2 63343 MILANO1 20040723 12 0 0.0% 3 3 100.0% 0 0NE-RNC-2 63343 MILANO1 20040724 3 0 0.0% 0 0 0 0NE-RNC-2 63343 MILANO1 20040725 5 0 0.0% 0 0 0 0NE-RNC-2 63343 MILANO1 20040726 30 0 0.0% 3 3 100.0% 0 0

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63343 MILANO1 2004070123 42.9863343 MILANO1 2004070200 42.9863343 MILANO1 2004070201 42.9863343 MILANO1 2004070202 42.9863343 MILANO1 2004070203 42.9863343 MILANO1 2004070204 42.9863343 MILANO1 2004070205 42.9863343 MILANO1 2004070206 42.9863343 MILANO1 2004070207 42.9863343 MILANO1 2004070208 42.9863343 MILANO1 2004070209 42.9963343 MILANO1 2004070210 42.9863343 MILANO1 2004070211 42.9963343 MILANO1 2004070212 42.9963343 MILANO1 2004070213 42.9863343 MILANO1 2004070214 42.99


ProcessThe process used during the troubleshooting was the following:

1. Identify cells with high daily base AC_RRC Setup Failure Rate

2. Compare hourly AC_RRC Setup Failure Rate with UL/DL DCH Reject Rate Sign to identify critical hours

3. If DCH requests are not incremented check Cell Availability in the specified hours:1. If Cell Availablity < 100% case 1

4. If UL DCH Reject Rate Sign ~ DL DCH Reject Rate Sign check Cell Availability in the specified hours:1. If Cell Availablity < 100% case 1

5. If UL DCH Reject Rate Sign >> DL DCH Reject Rate Sign check Average PrxTotal class 0 :1. If Average PrxTotal class 0 >> background noise (~ -102 dBm) case 2

6. If UL DCH Reject Rate Sign << DL DCH Reject Rate Sign check Average PtxTotal class 0 :1. If Average PtxTotal > power of common channels case 3


Case 4: DyLo rejects 384 in DL• There is an additional case of Admission Control blocking during RAB

Reconfiguration from 64384• DL 384 DCH allocation requests are blocked by Dynamic Link

Optimisation although the DL Power will not exceed the threshold.• User perception is low throughput • Blocking are not visible at RRC and RAB level but only using traffic

table counters.• Diagnostic through counters and KPI:

• DL DCH Reject Rate PS > 70%• DL DCH Duration PS 384 < 40% (depending on the users profile)• Ptx Percentage of time in class 3/4 ~ 0% (showing that the cell is never in

DL overload)• Additional counter can be used to detect the problem:

• High number of DL capacity requests: • KPIs and counters can give only an advice, the problem should be

confirmed only through field testing.• Cause: DyLo rejects the 384 dch allocation• Solution: site restarting is not enough, delete and recreate the COCO


CE

LL_I

D

RN

C-C

ITT

A

DA

Y

RR

C_C

ON

N_S

TP

_AT

T

RR

C_C

ON

N_S

TP

_FA

IL_A

C

AC

_RR

C_S

ET

UP

_FA

IL_R

AT

E

RA

B_S

TP

_AT

T_C

S_V

OIC

E

RA

B_S

TP

_FA

IL_C

S_V

OIC

E_A

C

AC

_RA

B_A

MR

_SE

TU

P_F

AIL

_RA

TE

RA

B_S

TP

_AT

T_C

S_C

ON

V

RA

B_S

TP

_FA

IL_C

S_C

ON

V_A

C

AC

_RA

B_C

SC

ON

V_S

ET

UP

_FA

IL_R

AT

E

RA

B_S

TP

_AT

T_P

S

RA

B_S

TP

_FA

IL_P

S_A

C

AC

_RA

B_P

S_S

ET

UP

_FA

IL_R

AT

E

51162 TORINO 20040910 313 0 0.0% 29 0 0.0% 0 0 18 0 0.0%51162 TORINO 20040902 294 0 0.0% 35 0 0.0% 0 0 8 0 0.0%51162 TORINO 20040903 235 0 0.0% 37 0 0.0% 1 0 0.0% 34 0 0.0%51162 TORINO 20040904 244 0 0.0% 7 0 0.0% 0 0 103 0 0.0%51162 TORINO 20040905 171 0 0.0% 11 0 0.0% 0 0 31 0 0.0%51162 TORINO 20040906 217 0 0.0% 30 0 0.0% 0 0 20 0 0.0%51162 TORINO 20040907 359 0 0.0% 50 0 0.0% 3 0 0.0% 49 0 0.0%51162 TORINO 20040901 455 0 0.0% 53 0 0.0% 0 0 95 0 0.0%51162 TORINO 20040909 411 0 0.0% 41 0 0.0% 1 0 0.0% 63 0 0.0%51162 TORINO 20040917 282 0 0.0% 24 0 0.0% 0 0 48 0 0.0%51162 TORINO 20040911 446 0 0.0% 34 0 0.0% 0 0 108 0 0.0%51162 TORINO 20040912 312 0 0.0% 23 0 0.0% 0 0 88 0 0.0%51162 TORINO 20040913 291 0 0.0% 24 0 0.0% 0 0 13 0 0.0%51162 TORINO 20040914 423 0 0.0% 46 0 0.0% 1 0 0.0% 116 0 0.0%51162 TORINO 20040915 354 0 0.0% 48 0 0.0% 0 0 67 0 0.0%51162 TORINO 20040916 837 0 0.0% 48 0 0.0% 1 0 0.0% 163 0 0.0%51162 TORINO 20040908 391 0 0.0% 45 0 0.0% 0 0 63 0 0.0%

Case 4: DyLo rejects PS 384 in DL• The cell is suffering blocking in DL DCH allocation for PS

• No blocking in RRC and RAB Setupblocking during RAB reconfiguration

• DyLO rejects the RAB reconfiguration if the DL power of the new radio link exceeds the maximum power - Dylo offset

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

2004

0825

2004

0826

2004

0827

2004

0828

2004

0829

2004

0830

2004

0831

2004

0901

2004

0902

2004

0903

2004

0904

2004

0905

2004

0906

2004

0907

2004

0908

2004

0909

2004

0910

2004

0911

2004

0912

2004

0913

2004

0914

2004

0915

2004

0916

2004

0917

2004

0919

2004

0920

DL

Rej

ect

0

1000

2000

3000

4000

5000

6000

DL

Cap

acity

Req

uest

DL_DCH_Reject_Rate_PS DL_CAPACITY_REQ

0

2000

4000

6000

8000

10000

12000

14000

16000

9/25/2004 9/26/2004 9/27/2004 9/28/2004 9/29/2004

384 KBPS DCH ALLOCATION DURATION DL SRNC(sec) 128 KBPS DCH ALLOCATION DURATION DL SRNC(sec)

64 KBPS DCH ALLOCATION DURATION DL SRNC(sec)

COCO recreated


Interference Analysis


Evaluation of interference duration• VF-I uses PrxNoise=-92dBm and PrxNoiseMaxTuneAbsolute=0.5dB,

therefore PrxNoise autotunes between –92.5dBm and –91.5dBm

• Based on measured PrxTotClass0, we can assume that the interference signals are received well above –91.5dBm (in the range –90 to –75dBm)

• Therefore the average PrxNoise values is an average between • -92.5dBm for most of the time and• -91.5dBm when the interferer transmits

• If we call • Y the unloaded duration (DENOM_PRXTOT_CLASS_0) and • X the duration of the interference for the period where the cell is

unloaded (giving a minimum duration for the interference)

• Then• AVE_PRXNOISE=X/Y * (-91.5dBm) + (Y-X)/Y *(-92.5dBm) • And then the minimum duration of the interference is

60/110

1101.0

10/)5.92Pr(

)(min period

xNoiseAve

utes RRIYX


Principle

Y (unloaded measurements)

PrxNoise autotunes to –92.5dBm

-92dBm

Measured PrxTotal in

class 0

PrxNoise autotunes to –

91.5dBm

X (interfered measurements)


Example (1/2)• The interference duration is exactly the same on 2 sectors, although

the amplitude (Average PrxTot Class 0) is not the same

% Period > -92dBm

0

10

20

30

40

50

60

20

04

07

19

00

20

04

07

19

04

20

04

07

19

08

20

04

07

19

12

20

04

07

19

16

20

04

07

19

20

20

04

07

20

00

20

04

07

20

04

20

04

07

20

08

20

04

07

20

12

20

04

07

20

16

20

04

07

20

20

20

04

07

21

00

20

04

07

21

04

20

04

07

21

08

20

04

07

21

12

20

04

07

21

16

20

04

07

21

20

20

04

07

22

00

20

04

07

22

04

20

04

07

22

08

20

04

07

22

12

20

04

07

22

16

20

04

07

22

20

Hour

Min

imu

m D

ura

tio

n (

min

ute

s)

63762

63763

Ave PrxTot Class 0

-110.00

-105.00

-100.00

-95.00

-90.00

-85.00

-80.00

-75.00

2004

0719

00

2004

0719

05

2004

0719

10

2004

0719

15

2004

0719

20

2004

0720

01

2004

0720

06

2004

0720

11

2004

0720

16

2004

0720

21

2004

0721

02

2004

0721

07

2004

0721

12

2004

0721

17

2004

0721

22

2004

0722

03

2004

0722

08

2004

0722

13

2004

0722

18

2004

0722

23

Hour

dB

m 63762

63763


Amplitude and duration• From the duration and Ave PrxTot Class 0 the maximum amplitude can

be estimated, assuming that the level below –92dBm is negligible

Interference duration/Amplitude

-90

-88

-86

-84

-82

-80

-78

-76

-74

-72

0 10 20 30 40 50 60

Duration (min)

Am

plit

ud

e (

dB

m)


RAB Setup Failure Step 1:Identification of the worst performing cell

• Some of the bad performing cells for RAB Setup are the same for the RRC Setup.

• Most failures come from 63343 with LPA Alarm (visible at RRC level as well) and neighbouring cells (not visible at RRC level): 63342, 63901, 63903

RN

C_I

D

CE

LL_I

D

RN

C- C

ITT

A

RA

B_S

TP

_AT

T_C

S_V

OIC

E

RA

B_S

TP

_FA

IL_C

S_V

OIC

E_A

C

AC

_RA

B_A

MR

_SE

TU

P_F

AIL

_RA

TE

RA

B_S

TP

_AT

T_C

S_C

ON

V

RA

B_S

TP

_FA

IL_C

S_C

ON

V_A

C

AC

_RA

B_C

SC

ON

V_S

ET

UP

_FA

IL_R

AT

E

NE -RNC -2 63343 MILANO1 52 52 100.0% 0 0

NE-RNC -3 61691 MILANO2 3967 18 0.5% 47 0 0.0%

NE-RNC -3 62092 MILANO2 1404 9 0.6% 46 0 0.0%

NE-RNC -3 63511 MILANO2 1045 8 0.8% 65 0 0.0%

NE-RNC -2 63901 MILANO1 53 8 15.1% 1 0 0.0%

NE-RNC -2 63342 MILANO1 56 7 12.5% 0 0

NE-RNC -2 63902 MILANO1 70 7 10.0% 7 0 0.0%

NE-RNC -3 63322 MILANO2 586 4 0.7% 6 0 0.0%

RN

C_I

D

CE

LL_I

D

RN

C- C

ITT

A

RA

B_S

TP

_AT

T_C

S_V

OIC

E

RA

B_S

TP

_FA

IL_C

S_V

OIC

E_A

C

AC

_RA

B_A

MR

_SE

TU

P_F

AIL

_RA

TE

RA

B_S

TP

_AT

T_C

S_C

ON

V

RA

B_S

TP

_FA

IL_C

S_C

ON

V_A

C

AC

_RA

B_C

SC

ON

V_S

ET

UP

_FA

IL_R

AT

E

NE -RNC -2 63343 MILANO1 52 52 100.0% 0 0

NE-RNC -3 61691 MILANO2 3967 18 0.5% 47 0 0.0%

NE-RNC -3 62092 MILANO2 1404 9 0.6% 46 0 0.0%

NE-RNC -3 63511 MILANO2 1045 8 0.8% 65 0 0.0%

NE-RNC -2 63901 MILANO1 53 8 15.1% 1 0 0.0%

NE-RNC -2 63342 MILANO1 56 7 12.5% 0 0

NE-RNC -2 63902 MILANO1 70 7 10.0% 7 0 0.0%

NE-RNC -3 63322 MILANO2 586 4 0.7% 6 0 0.0%


RAB Setup Failure Step 2:Cell Analysis: 63342,63901,63902

• Looking at the site positions all the cells are neighbour to the 63343!

63343: LPA alarm63341

63901

63902


RAB Setup Failure Step 2:Cell Analysis:63901

• RRC Setup are ok

• RAB Voice Setup shows AC blocking but from Traffic Table no DCH are rejected

• The cell is able to admit RAB dch but than the RAB Assignement Request is rejectedblocking may be due to some other cells in sho during the RAB establishment with the 63901 as reference cell (Service Level counters are incremented for the reference cell)

RN

C_

ID

CE

LL

_ID

RN

C-C

ITTA

DA

Y

RR

C_

CO

NN

_S

TP

_A

TT

RR

C_

CO

NN

_S

TP

_F

AIL

_A

C

AC

_R

RC

_S

ET

UP

_F

AIL

_R

AT

E

RA

B_

ST

P_

AT

T_

CS

_V

OIC

E

RA

B_

ST

P_

FA

IL_

CS

_V

OIC

E_

AC

AC

_R

AB

_A

MR

_S

ET

UP

_F

AIL

_R

AT

E

RA

B_

ST

P_

AT

T_

CS

_C

ON

V

RA

B_

ST

P_

FA

IL_

CS

_C

ON

V_

AC

AC

_R

AB

_C

SC

ON

V_

SE

TU

P_

FA

IL_

RA

TE

RA

B_

ST

P_

AT

T_

PS

RA

B_

ST

P_

FA

IL_

PS

_A

C

AC

_R

AB

_P

S_

SE

TU

P_

FA

IL_

RA

TE

NE-RNC-2 63901 MILANO1 20040719 68 0 0.0% 7 1 14.3% 0 0 35 0 0.0%NE-RNC-2 63901 MILANO1 20040720 157 0 0.0% 0 0 0 0 123 0 0.0%NE-RNC-2 63901 MILANO1 20040721 195 0 0.0% 23 7 30.4% 0 0 63 0 0.0%NE-RNC-2 63901 MILANO1 20040722 272 0 0.0% 7 0 0.0% 0 0 173 0 0.0%NE-RNC-2 63901 MILANO1 20040723 422 0 0.0% 10 0 0.0% 1 0 0.0% 331 0 0.0%NE-RNC-2 63901 MILANO1 20040724 12 0 0.0% 0 0 0 0 0 0NE-RNC-2 63901 MILANO1 20040725 9 0 0.0% 1 0 0.0% 0 0 1 0 0.0%NE-RNC-2 63901 MILANO1 20040726 33 0 0.0% 5 0 0.0% 0 0 13 0 0.0%

RN

C_I

D

CE

LL_I

D

RN

C-C

ITTA

DA

Y

RE

Q_C

S_V

OIC

E_I

N_S

RN

C

RE

Q_C

S_V

OIC

E_R

EJ_

UL_

SR

NC

RE

Q_C

S_V

OIC

E_R

EJ_

DL_

SR

NC

UL_

DC

H_R

ejec

t_R

ate_

Voi

ce

DL_

DC

H_R

ejec

t_R

ate_

Voi

ce

DC

H_D

urat

ion_

Voi

ce

NE-RNC-2 63901 MILANO1 20040719 35 0 0 0.0% 0.0% 331.35NE-RNC-2 63901 MILANO1 20040720 20 0 0 0.0% 0.0% 151.98NE-RNC-2 63901 MILANO1 20040721 119 0 0 0.0% 0.0% 1896.44NE-RNC-2 63901 MILANO1 20040722 23 0 0 0.0% 0.0% 319.53NE-RNC-2 63901 MILANO1 20040723 20 0 0 0.0% 0.0% 420.35NE-RNC-2 63901 MILANO1 20040724 0 0 0 0NE-RNC-2 63901 MILANO1 20040725 1 0 0 0.0% 0.0% 2.6NE-RNC-2 63901 MILANO1 20040726 11 0 0 0.0% 0.0% 130.79


RAB Setup Failure Step 2:Cell Analysis:63901

• From Cell Resource KPI no problems are visible: • Cell Availability is 100%• PrxTotal is OK• PtxTotal is Ok, showing some

DL traffic

• Cell 63901 is neighbour to 63343!

• Possible scenario: 1. RRC setup in 63901 is successful2. During RRC, Cell Addition for

63343 is possible because PtxTotal (43 dBm) is below PtxTarge+ PtxOffset (= 45 dB)

3. RAB Assignement request is received by the two cells in SHO

4. Voice DCH request is accepted by 63901 but rejected by 63433

5. RAB Assignement Request is rejected and the RAB Voice Setup Failure for AC is incremented in the 63901 which is the reference cell.

RN

C_

ID

CE

LL

_ID

RN

C-C

ITTA

HO

UR

DE

NO

M_

CO

DE

_C

AP

AC

ITY

Ce

ll_A

vaila

bili

ty

Ave

rag

e_

Prx

Tota

l_cl

ass

_0

Prx

_T

ime

_in

_cl

ass

_3

Prx

_T

ime

_in

_cl

ass

_4

Ave

rag

e_

Ptx

Tota

l_e

xcl_

0

Ptx

_T

ime

_in

_cl

ass

_3

Ptx

_T

ime

_in

_cl

ass

_4

NE-RNC-2 63901 MILANO1 2004072100 179 99.4% -107.50NE-RNC-2 63901 MILANO1 2004072101 180 100.0% -107.60 35.79 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072102 180 100.0% -107.60NE-RNC-2 63901 MILANO1 2004072103 180 100.0% -107.60NE-RNC-2 63901 MILANO1 2004072104 180 100.0% -107.60NE-RNC-2 63901 MILANO1 2004072105 180 100.0% -107.60NE-RNC-2 63901 MILANO1 2004072106 180 100.0% -107.60 35.54 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072107 180 100.0% -107.60 0.0% 0.0% 35.59 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072108 180 100.0% -107.60 0.0% 0.0% 35.63 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072109 180 100.0% -107.50 0.0% 0.0% 35.61 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072110 179 99.4% -107.60 0.0% 0.0% 35.79 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072111 180 100.0% -107.70 0.0% 0.0% 35.79 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072112 180 100.0% -107.70 0.0% 0.0% 35.83 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072113 180 100.0% -107.70 0.0% 0.0% 35.59 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072114 180 100.0% -107.70 0.0% 0.0% 35.56 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072115 180 100.0% -107.70 0.0% 0.0% 35.59 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072116 180 100.0% -107.60 0.0% 0.0% 35.60 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072117 180 100.0% -107.70 0.0% 0.0% 35.56 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072118 180 100.0% -107.70 35.55 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072119 180 100.0% -107.70 35.57 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072120 180 100.0% -107.70 35.70 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072121 180 100.0% -107.60 35.79 0.0% 0.0%NE-RNC-2 63901 MILANO1 2004072122 179 99.4% -107.60NE-RNC-2 63901 MILANO1 2004072123 180 100.0% -107.60






Agenda


PrxNoise Autotuning in Milan


UL Interference PrxNoise Autotuning

• 2nd of August the PrxNoise autotuning algorithm has been activated in Milano RNCs by setting the parameter:

• RNC PRxNoiseMaxTune Absolute 0.5 dB 20 dB

• PrxTarget is kept to 4 dBless margin

• 3rd of August some cells have experienced AC blocking for high UL interference

CE

LL_I

D

RN

C-C

ITTA

DA

Y

RR

C_C

ON

N_S

TP

_AT

T

RR

C_C

ON

N_S

TP

_FA

IL_A

C

AC

_RR

C_S

ET

UP

_FA

IL_R

AT

E

RA

B_S

TP

_AT

T_C

S_V

OIC

E

RA

B_S

TP

_FA

IL_C

S_V

OIC

E_A

C

AC

_RA

B_A

MR

_SE

TU

P_F

AIL

_RA

TE

RA

B_S

TP

_AT

T_C

S_C

ON

V

RA

B_S

TP

_FA

IL_C

S_C

ON

V_A

C

AC

_RA

B_C

SC

ON

V_S

ET

UP

_FA

IL_R

AT

E

RA

B_S

TP

_AT

T_P

S

RA

B_S

TP

_FA

IL_P

S_A

C

AC

_RA

B_P

S_S

ET

UP

_FA

IL_R

AT

E

62092 MILANO2 20040803 1331 129 9.7% 261 3 1.1% 123 1 0.8% 269 1 0.4%63511 MILANO2 20040803 547 83 15.2% 66 0 0.0% 41 2 4.9% 111 3 2.7%58773 MILANO2 20040803 54 16 29.6% 4 4 100.0% 0 0 15 0 0.0%

New PrxTarget


UL Interference Cell Analysis 62092: PrxNoise autotuning

• From PM ticket failures are between 4 and 4:23 pm (~23 min.)

• On average PrxNoise seems to follow the interference

• Time in overload (denom in class4) is ~ 7% (4 min.)interference is not constantly over the target

-105-104-103-102-101-100-99-98-97-96-95-94-93-92-91-90-89-88-87-86-85

20

04

08

03

00

20

04

08

03

02

20

04

08

03

05

20

04

08

03

07

20

04

08

03

09

20

04

08

03

11

20

04

08

03

13

20

04

08

03

15

20

04

08

03

17

20

04

08

03

19

20

04

08

03

21

20

04

08

03

23

hour

dB

m

AVG_PRX_PWR AVE_PRX_NOISE PrxTragte

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

2004

0803

00

2004

0803

01

2004

0803

02

2004

0803

03

2004

0803

05

2004

0803

06

2004

0803

07

2004

0803

08

2004

0803

09

2004

0803

10

2004

0803

11

2004

0803

12

2004

0803

13

2004

0803

14

2004

0803

15

2004

0803

16

2004

0803

17

2004

0803

18

2004

0803

19

2004

0803

20

2004

0803

21

2004

0803

22

2004

0803

23

den

om

0,1

050

010

0015

0020

00

den

om

2,3,

4

prxtot_denom_0 prxtot_denom_1 prxtot_denom_2

prxtot_denom_3 prxtot_denom_4


UL Interference Cell Analysis 63101: autotuning on and off

• PrxNoise autotuning allows the PrxTarget following the interference peaks

-110

-105

-100

-95

-90

-85

-80

-75

-70

1

44

87

13

0

17

3

21

6

25

9

30

2

34

5

38

8

43

1

47

4

51

7

56

0

60

3

64

6

68

9

73

2

77

5

81

8

86

1

PrxTot

Avrg Noise

PrxTarget

Autotuning is blocked by +/-0.5 dB

Autotuning is not blocked and prevents some failures


Autotuning Conclusions• Autotuning could prevent some Admission Control failure by changing

the reference of the scale

• Autotuning is updated only if the cell in “unloaded”

• Failures can happen if:• The interference occurs when the cell is loaded• There are hanging resources in the cell• The interference peaks are very quick (the autotuning algorithm

allows increase of 0.3dB every RRI, 200ms, i.e. 1.5dB/s)

• Additional tests is required to confirm the benefits of the algorithm.

%1

AND %2

:CELL OWN

NRT

RT

L

L

%1

AND %2

:CELL OWN

NRT

RT

L

L

PrxNoise autotuned

Uplink LoadPrxNoise


PrxTarget tuning in Paris


Admission Control Parameters in SFR• SFR Admission Control parameters:

• UL AC:• PrxTarget = 3 dB• PrxOffset = 1 dB

• Load Control:• PrxNoiseAutotuning = true• PrxNoise = -104 dBm • PrxNoiseMaxTuneAbsolute = 20 dB


PrxNoise Counters• PRX_NOISE_DENOM_1 is number of RRI when PrxNoise is updated

(same as PRXTOT_DENOM_0)

• AVE_PRX_NOISE, MAX_PRX_NOISE_VALUE and MIN_PRX_NOISE_VALUE are average, maximum and minimum values of the autotuned PrxNoise


Interference characteristics• Frequency (Continuous/Frequent/Rare)

• Can be seen from number of OSS periods where we see interference

• Continuous interference are the most detrimental to performance• Duration (Spurious/Short/Long)

• When the interference is lasting long within an OSS period the Average PrxNoise value will be affected

• Long interference is most detrimental to performance• Absolute Amplitude

• In non interfered case the Average PrxNoise is around –104dBm• Higher values will impact directly the link budget and coverage,

also SHO performance will be affected as UL/DL balance is different of neighbouring cells

• Relative Amplitude Variation• The interference is generally not continuous and PrxNoise will vary

a lot: The difference between Maximum and Minimum PrxNoise will indicate the Variation in Amplitude

• High values mean that PrxNoise Autotuning will have difficulties to track the interference and that Admission Control can fail, also Power Control will have more challenges to maintain the radio link quality


• For an optimal detection, PrxNoise Autotuning should be on:• It will support combat interference in the Admission phase• It provides a wealth of counters

• With default parameters (WCEL:PrxNoise=-104dBm, RNC:PrxNoiseMaxTuneAbsolute=20dB) the maximum autotuned value is –84dBm

• Average PrxNoise• Indicates interference when above ~-100dBm• Can also be the sign of incorrect MHA commissionning

• Average amplitude of PrxNoise variation (or Average PrxNoise)• Indicates interference when above ~5dB• Can be the sign of continuous/low variation or of short/high

variation

What indicators for interference detection ?

DENOM_1PRX_NOISE_

10DENOM_1PRX_NOISE_log10

ISE/10AVE_PRX_NO

DENOM_1PRX_NOISE_

10DENOM_1PRX_NOISE_log10

ISE)/10MIN_PRX_NO-OISE(MAX_PRX_N


• Ratio of unloaded measurements where PrxNoise is higher than X dB• Indicates frequent interference when higher than ~10%• Depending on the value of X it will filter the highest variations

What indicators for interference detection ?

DENOM_1PRX_NOISE_

DENOM_1PRX_NOISE_XISE_VALUEMAX_PRX_NO-ISE_VALUEMAX_PRX_NO


AC Parameter changes• As a temporary solution, DL AC settings can be changed to

accomodate• When the interference source is eliminated, the normal settings

should be replaced

• In Nokia-optimised Paris cluster PrxTarget has been changed to:• 10dB if Ratio{Max-Min>10dB}>10%

• 8 cells were impacted (2% of cluster)• 5dB if Ratio{Max-Min>5dB}>10%

• 21 cells were impacted (6% of cluster)

RN

C_N

AM

E

WB

TS

_N

AM

E

WC

EL_

GID

WC

EL_

NA

ME

WC

EL_

ID

Avg

OfD

elta

Ma

xOfD

elta

Sum

OfM

ore

3

Sum

OfM

ore

5

Sum

OfM

ore

10

Sum

OfM

ore

15

Sum

OfM

ore

20

Sum

OfM

ore

25

Ptx

Tar

get

RNCNmit21 P_D_PEREUR_U 76129001 P_D_PEREUR_U0_F2 15349 8 27.67 101 84 34 5 2 2 10RNCNmit21 PARIS_NATION_U 71370001 PARIS_NATION_U1_F0 50190 11 25.07 109 97 54 19 8 1 10RNCNmit21 P_D_PEREUR_U 76127001 P_D_PEREUR_U0_F0 15344 6 28.07 76 61 20 6 1 1 10RNCNmit21 P_D_PEREUR_U 76128001 P_D_PEREUR_U0_F1 15345 3 27.07 32 18 5 3 1 1 5RNCNmit21 P_VILLETTE_U 6209001 P_VILLETTE_U0_F0 53919 3 21.05 25 13 7 6 3 0 5RNCNmit21 P_ST_ANTOINE_U 76237001 P_ST_ANTOINE_U2_F0 23662 4 21.03 51 36 11 4 3 0 5RNCNmit21 P_GALLIENI_U 1493001 P_GALLIENI_U1_F0 44198 4 21.24 44 32 15 7 2 0 10RNCNmit21 P_ST_ANTOINE_U 76235001 P_ST_ANTOINE_U0_F0 23649 3 22.39 34 17 4 2 2 0 5RNCNmit21 MONT_HERMITA_U 3153001 MONT_HERMITA_U2_F0 42233 2 21.66 16 12 7 2 2 0 5RNCNmit21 P_BAGNOLET_U 63134001 P_BAGNOLET_U1_F0 58179 3 20.44 20 13 5 4 1 0 5RNCNmit21 PRE_ST_GERVAI_ 62928001 PRE_ST_GERVAI_U0_F0 54621 2 21.57 13 12 6 3 1 0 5RNCNbez21 P_CHP_ELYSEE_U 77270001 P_CHP_ELYSEE_U1_F0 50456 5 22.56 75 41 8 2 1 0 5RNCNmit21 P_BD_REUILLY 9249001 P_BD_REUILLY_U2_F0 44457 3 20.25 27 13 2 1 1 0 5RNC_val31 PARIS_REPUB_U 72453001 PARIS_REPUB_U1_F0 58960 3 20.29 26 21 3 1 1 0 5RNC_val31 CHARENTO_POST_U 7682001 CHARENTO_POST_U1_F0 51614 2 23.36 18 13 4 1 1 0 5RNC_val31 P_PL_L_BERNS_U 74699001 P_PL_L_BERNS_U1_F0 64640 5 19.55 46 38 26 11 0 0 10RNCNmit21 P_OP_BASTILLE_U 5612001 P_OP_BASTILLE_U0_F0 64648 8 19.75 111 103 22 4 0 0 10RNCNmit21 AUBERVIL_VILL_U 5653001 AUBERVIL_VILL_U2_F0 46726 2 19.99 21 14 6 4 0 0 5RNCNmit21 MONT_HERMITA_U 3151001 MONT_HERMITA_U0_F0 22769 2 19.97 17 13 5 4 0 0 5RNCNbez21 P_CHP_ELYSEE_U 76967001 P_CHP_ELYSEES_U0_F0 38703 10 19.48 111 109 54 3 0 0 10RNCNmit21 PANTI_DEBARCA_U 4458001 PANT_DEBARCA_U0_F0 42288 2 18.04 17 14 6 3 0 0 5RNC_val31 P_DUQUESNE_U 201001 P_DUQUESNE_U0_F0 64618 9 15.42 84 84 59 2 0 0 10RNCNmit21 P_ST_ANTOINE_U 76236001 P_ST_ANTOINE_U1_F0 23654 2 19.18 26 13 3 2 0 0 5RNCNmit21 P_DEBRE_HOPIT_U 7269001 P_DEBRE_HOPIT_U0_F0 26565 2 16.79 18 15 3 1 0 0 5RNC_val31 P_NEMOURS_U 65748001 P_NEMOURS_U0_F0 57354 2 8.64 29 16 0 0 0 0 5RNCNmit21 P_PELLEPORT_U 5310001 P_PELLEPORT_U2_F0 44184 2 14.24 23 16 5 0 0 0 5RNC_val31 P_PARADIS_U 63337001 P_PARADIS_U0_F0 64524 2 14.32 21 17 2 0 0 0 5RNCNmit21 MONT_HERMITA_U 3152001 MONT_HERMITA_U1_F0 41737 2 13.96 17 13 9 0 0 0 5RNCNmit21 P_LA_CHAPELL_U 4929001 P_LA_CHAPELL_U1_F0 50638 1 9.29 16 13 0 0 0 0 5


Impact on RRC Setup failure• After the change, RRC Setup failure due to AC is reduced greatly on

those 29 cells and at cluster level

0

5000

10000

15000

20000

25000

30000

30/08/2004 31/08/2004 01/09/2004 02/09/2004 03/09/2004 06/09/2004 07/09/2004 08/09/2004 09/09/2004 10/09/2004

0%

1%

2%

3%

4%

5%

6%

7%

8%

9%

29 cells attemps

All cluster attempts

29 cells ratio

All cluster ratio

PrxTarget change on 29 cells


Remaining issues• Still some cells have AC blocking

• Reason #1• The interference on those cells is more spurious, i.e. it occurs in

less than 10% of the measurements• Therefore it was not included in the PrxTarget increase

• Reason #2• When there is some traffic in the cell, PrxNoise autotuning stops• If interference increases then, the cell will go in overload state• In this case AVE_PRXTOT_CLASS_4-AVE_PRXTOT_CLASS_3 will

be high (more than 3dB)

• More observation time is required to draw final conclusions


Ratio of time Max-Min>5dB

Most affected cells (continuous interference and

AC blocking)


External interference follow-up process (proposed)PrxNoise

Autotuning=ON

PrxNoise PI Monitoring

Threshold exceeded

?

Interference report:•PrxNoise (Max/Min/Avg) evolution over 1-2 weeks (hourly)

•Snapshot of Online Monitoring

Champs Elysées U0 (38703)

-110

-108

-106

-104

-102

-100

-98

-96

-94

-92

-90

16/0

8/20

04 0

8

16/0

8/20

04 1

2

16/0

8/20

04 1

6

16/0

8/20

04 2

0

17/0

8/20

04 1

0

17/0

8/20

04 1

4

17/0

8/20

04 1

8

18/0

8/20

04 0

8

18/0

8/20

04 1

2

18/0

8/20

04 1

6

18/0

8/20

04 2

0

19/0

8/20

04 1

0

19/0

8/20

04 1

4

19/0

8/20

04 1

8

20/0

8/20

04 0

8

20/0

8/20

04 1

2

20/0

8/20

04 1

6

20/0

8/20

04 2

0

23/0

8/20

04 1

0

23/0

8/20

04 1

4

23/0

8/20

04 1

8

24/0

8/20

04 0

9

24/0

8/20

04 1

3

24/0

8/20

04 1

7

24/0

8/20

04 2

1

25/0

8/20

04 1

1

25/0

8/20

04 1

5

25/0

8/20

04 1

9

AVE_PRX_NOISE_VALUE

MAX_PRX_NOISE_VALUE

MIN_PRX_NOISE_VALUE

Spurious ?

MaintenanceMeasurements

Regulator

Interference Cleared ?

Search mobile

Rogue mobile ?

Y

N

Y

N

Increase PrxTarget

Decrease PrxTargetY






Agenda


Discussion• According to Nokia information PrxTarget=

• 3dB in France• 4dB in Italy• 5dB in Belgium• 6dB in Japan• 30dB in Sweden

• What margin is available in VF standard design link budget ?

• Is there scope for harmonisation ?


Possible next steps• Pre-requisite is an high traffic

cell.

• Change parameters for filtering the interference spikes

• PrxMeasAveWindow (WBTS)• PrxAlpha (WBTS)• WinACRabSetupUL (WBTS)

• ISHO for Ue Tx Power and UL quality:

• GsmUETxPwrThrNrtPS (FMCG)• GsmUETxPwrThrAMR (FMCG)• GSMcauseUplinkQuality (FMCG)• EnableULQualDetRep (RNC)• ULQualDetRepThreshold(RNC)

0

10

20

30

40

50

60

70

20

04

09

06

20

04

09

07

20

04

09

08

20

04

09

09

20

04

09

10

20

04

09

11

20

04

09

12

20

04

09

13

IS_COM_MOD_STA_NOT_POS_RT

UE_PWR_RT

Interference starts Sept. 9th

Is it possible to smooth the interference?

ul interference

Documents