08 2e europe rf experience sharing 2%2e0

7/29/2019 08 2E Europe RF Experience Sharing 2%2E0

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NORTEL NETWORKS CONFIDENTIAL

European UMTS FieldExperience

Wireless Network Engineering

October , 2003


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Agenda

RF Design WCDMA Principles

Design Process and main considerations

RF Optimization

Optimization Stages

First Tuning Principles

First Tuning Process

Tools

Some Real examples

Lessons Learnt


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Agenda

RF DesignWCDMA Principles


RF Optimization Optimization Stages



Tools Some Real examples

Lessons Learnt


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Presentation Name - 3NORTEL NETWORKS CONFIDENTIAL

Coverage quality sensitive to traffic load.

Capacity usually limited by downlink Interference.

All neighbor cells are Co Channel interferers

Faster Handover Processing & Power Control essential

There will be a complex traffic mix, being really asymmetric.

The mobility pattern will also have direct impact in the final system

behavior.

Interference Control Critical for all CDMA-based Technologies.

Cloverleaf Pattern with 65 Deg Beam preferred for Macro cells with

optimized azimuth. Microcells can be Co Channel to Macro Layer.

WCDMA RF Characteristics

Goal to Balance QOS, Coverage, Capacity, cost


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Users with variety QoS demands under various RF environments(Note: GSM has one)

A more detailed interference planning and capacity analysis is

required

Interference estimation is even more crucial in the coverageprediction phase (Cell breathing phenomenon)

The whole planning process has to be done iteratively through

air interface simulation as each user is influencing the others

Comparison GSM vs UMTS (1/2)

GSM 2G network designed primarily for Voice services, some

data traffic has been included with GPRS

UMTS - 3G network de

signed primarily for multi-services (PacketData Services, Circuit Data Services, Voice)

UMTS radio network design requirements

are more complex compared to Traditional GSM


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GSM

Capacity is closely related to theinstalled equipment

Quality of channels primarily

impacted by co- & adj- channel

interference.

Sequential planning process

Coverage, Capacity largely

sequential

Capacity can be obtained by

HW increase with no impact on

coverage

UMTS

Capacity is not only related tothe installed hardware

Quality and capacity impactedby both intra-cell and inter-celleffects

Interrelated process

Coverage and Capacity: find

balance

Comparison GSM vs UMTS (2/2)


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Initial Inputs To be considered

Geographic

Environment Antenna height

Penetration factors / Propagation Model

Services (QoS, guarantee along areas & traffic) Speech

CS data PS data

Product Performances BS

MS

Quality of coverage Coverage areas and associated Area reliability

Type of coverage

UE

BTS

BTS


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Impact of the services in the network

Design Higher rate services have a shorter possible distance

SF =256

Speech

Spreading Factor

Relative distance

Low speedData

SF = 32

SF = 8

High speedData

Node B(BTS)


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As seen, the higher the throughput of the RAB is, the lower is theCell Range (Higher power is allocated to each user)

The final traffic will be a mix of all the available RABs, with acertain weight distribution, and also with a certain activity factors(strongly driven by the application that will be finally used)

In the initial stages, the load in the network will be light, thus aninitial good basic radio design should be able to warranty a goodradio quality

As the number of users will start increasing, the forecasted loadwill increase also; an important role will be played by the per RABuser profile:

If the activity factor is high, the radio conditions will be under a severe load. If the activity factor is low, the radio conditions will remain, as there will be blocking

due to parameter configuration

Impact of the services in the network

Design


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A simple solution is the best...

The traffic profile is something unpredictable.

The user behavior is also unpredictable. The final site locations are also unknown.

The environment impacts performance, and the way it changes is

also unpredictable

All those variables have got a direct impact on the performanceof the network, and they are not controlled by the operator;

therefore a simplified design approach is the only sensible one...

A simple approach would be the most effective solution


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Agenda



RF Optimization Optimization Stages First Tuning Principles


Tools Some Real examples

Lessons Learnt


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Define a link budget based on the most restrictive RAB that willbe used in the system; the main goal of the link budget will be to

find out the allowed Path loss. Define the inter-site distance that will be used in each of the

environments for the design based on a calibrated propagationmodel.

Generate a nominal design, based on the estimated inter-sitedistance, tuned with the knowledge of the traffic distribution in

the area; this nominal design should be generated with a WCDMAplanning tool (like iPlanner). A calibrated model should be used.

An initial traffic estimation would be needed to have an initial idea of the load thatcan be expected to be supported by Radio Network.

The predictions will never have the same level of accuracy than the real datacoming from statistics from the field; the real user behavior and mobility is

unpredictable...

Simple approach (1/2)

This initial steps will drive the evolution of the network

rollout


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Look forreal concrete candidates for each of the nominal cellsites: The candidate should have an average height regarding its surrounding clutter; if it

is too tall it will interfere too much and Radio will be uncontrollable; if it is too low, itmay not achieve the coverage objective.

The candidates should be achievable; this will depend on the acquisitionparticularities of each region.

There must be enough space in the roof to place properly the antennas, there is asignificant impact of the right antenna with the right layout on the site

performance. Coordination with other operators may be needed.

Validation of the site construction project would be needed.

Once the site has been installed, it should be commissioned andintegrated with the initial parameter settings.

Pre-launch optimization phase should be started once a

significant amount of sites in a cluster has been integrated

Simple approach(2/2)

The most important steps are the ones impacting the

detailed implementation of the network like candidate

selection and antenna layout


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Actual Radio Design

Used values in

our project:

ISD ~ 400m / 200m

Antenna Height ~ 25m

Horizontal BW 65

Vertical BW 7

VET up to 7


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Control of Coverage & Interference is critical !

Cell Planning ConsiderationsKey RF Design Cons iderat ions

Minimize out-of-cell interference

Maximum use of sectorization in Urban areas

Minimize Soft Handoff levels & Pilot pollution where possible

Clear Dominant Server required

Use of regular Site Spacing & Antenna heights

Limitations in Planning tools to simulate real network

Rely more on real field experience/data where possible

Key RF Design metrics

CPICH EC/Io

UE TX power

Handover State


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RR

B B

H H

D = 2R > 2B

WCDMA RF Engineering

A Clean Textbook RF Design for Coverage

Define Reverse Link Budget from QOS Margins

Space Cells for Target Edge Signal Strength.

Adjust heights to contain Interference

Use Buildings as Interference Shields

Unlimited Bldg Penetration & QOS ???

It Doesnt lookToo Difficult ??


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Mobile TX Pwr vs Log D

-40

-30

-20

-10

0

10

20

-1 -0.5 0 0.5 1

log(d)

dBm

Slope ?

WCDMA RF Engineering

Real World CDMA Cells Fragment - Close Spacing presents many

conflicting challenges.

Path loss Slopes Flatter, More Patches of Overshoot Site Grid breaks up

Handoff Problems Increase

Longer Neighbor Lists

Longer Code Search times

Spectral Efficiency Loss

A prediction tool is only used as support...


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Excessive x-way (x > 3)

Soft-Handoff Area due

to lack of dominant server

Improved area by

applying down-tilt

and re-orienting site

Cell Planning ConsiderationsImpo rtance of Pilot Contro l o n Soft Handoff

Excessive

Soft-Handoff

reduced

Excessive Soft-

Handoff area

to be reduced

To control Pilot into desired areas at required levels

Soft Handoff levels reduction

Improve Downlink capacity

Minimize CE usage

A im

Results

Example

Reduce neighbor lists & longcode search times

Improve FER performance


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Flexibility in RF Coverage control is the most importantoptimization factor

High Cell edge reliability and building penetration loss,result in pilot pollution

Use downtilt and/or reduce height to confine coverage Antenna Selection

Greater performance with directional antennas in interference-limited areas like Urban

Choose site location to create dominant server area

CDMA analysis result dependant on traffic distribution

(good understanding, even, weighted) Use GSM Traffic distribution

Cell Planning ConsiderationsReview o f main Points

Pilot Ec/Io is the important threshold, not signal level

Coverage & Interference control !!


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Advantages of owning a 2G network

Knowledge of existing Traffic distribution @busyhours

More accurate data on traffic distribution maps

Knowledge of Performance for individual sitesI.e: eliminate tall & uncontrollable sites

Knowledge of areas with excessive GSM multipleservers

I.e: minimize potential Soft Handoffs problems in 3G


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Agenda

RF Design

WCDMA Principles


RF Optimization

Optimization Stages



Tools

Some Real examples

Lessons Learnt


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Optimizing UMTS networks

Objective of the Optimization activityAdjust the system resources available in each location so that:The system performance is optimized

The service perception of the end user is the best possible

Particularities

All the signal on the air is co-channel

The user behavior is hard to model

The traffic mix is becoming more complex

The services will become more and more asymmetric

What can be the an effective approach? Prepare the network for an initial activity

Validate a methodology and a set of tools to analyze the system

Closely monitor the evolution of the real users

Pre-Launch

Post-Launch


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Optimization Stages Pre-launch Optimization (First Tuning)

The main objective is to prepare network launch by validating sites

functionality and by performing basic network optimization through drive tests

1 2 34 5 67 8 9* 0 #

FTP

HTTP

PING

-

-

-

RNC

1 2 3

4 5 6

7 8 9

* 0 #

1 2 3

4 5 6

7 8 9

* 0 #

1 2 3

4 5 6

7 8 9

* 0 #

1 2 3

4 5 6

7 8 9

* 0 #

1 2 3

4 5 6

7 8 9

* 0 #

1 2 3

4 5 6

7 8 9

* 0 #

OMC1 2 34 5 67 8 9

* 0 #

Post-launch Optimization (Fine Tuning)

The main objective is to optimize performance of a network influenced by

traffic load, using real system performance data and/or drive tests data


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Agenda






Tools

Some Real examples

Lessons Learnt


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Main Considerations for first tuning (1/2)

RF control is the key in a CDMA network As everything is co-channel, parameter configuration may help up to a

certain level; there is a minimum base RF quality needed to achieve

Aim is to contain each sector to its intended coverage area

A poor coverage control may cause

no dominant server (poor Ec/Io, but high composite signal level) dropped calls due to slow Handoff

access to the wrong pilot and wrong neighbor list

excessive soft handoff (higher than average 4,5,6 way handoff)

higher than average downlink power

Coverage control should be exercised at the earlydesign stage

Pilot Ec/Io is the Key metric, not signal Level

Coverage & Interference Control !!


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Neighbour list definition is also very important to be defined so

that the present signal is used in the most effective way

Neighbour lists controls which Pilots the UE is assessing as

handoff candidates

Aim is to minimize per-sector neighbor list length without

compromising capacity, access fail and dropped call numbers

Main Considerations for first tuning (2/2)

Search time increases with longer neighbor lists Leads to possible Dropped calls


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GSM vs CDMA Optimization2G/GSM Prio rit ies

Frequency Planning (SFH, AFP) Reduce the co-channel & adjacent channels

interference

Minimize the signal overshoot into 2nd & 3rd server areas

Optimal Neighboring lists to avoid Call dragging

HO settings (Hysteresis, thresholds, etc)to avoid ping-pong

Traffic load management between layers

Capacity driven by network equipment installed

GSM CDMA O i i i


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Code Planning (Easier than GSM BCCH reuse planning)

Greater Emphasis on Coverage / Pilot Control

Soft Handoff Control

Thresholds based on absolute Ec/Io criteria

CDMA less likely to require per site parameter optimization. More adjustments made on

RF Control & not using Parameter settings

Neighbor Planning

Optimal neighbor lists: minimal but accurate!

Capacity distinction between UL (Noise Floor) & DL (PA usage)

Power Allocation Distribution

Adjust Max Power Per User to balance capacity and performance

More power per user = less capacity (All users share same PA)

Higher power per user necessary at Network borders to compensate for lack of SHO

GSM vs CDMA Optimization2G/CDMA Prio rit i es


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Agenda






Tools

Some Real examples

Lessons Learnt


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Main metrics to be used along the

process

RF Quality indicators CPICH Ec/Io (dB) Received energy per chip divided by the power density in the band i.e. it is

identical to the RSCP measured on the CPICH divided by the RSSI.

Active Set SizeNumber of Radio Links established simultaneously by the UE

Application layer Metrics

Mean Holding time In some stages, can be useful to start performing continuous calls drivetests

Dropped Call Rate Number of Calls abnormally terminated; traditionally implemented oncontrolled duration calls.

Call Setup Success Percentage of calls established related to the number of attempted calls Successful Calls Percentage of calls that could be normally established, maintained and

terminated normally


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First Tuning Process (1/2)

Site Shakedown

Cluster Analysis (iterative)

Pilot Optimization Drive

Radio Verification Drive

Network Analysis

(iterative)


Radio Verification Drive


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Analysis to be performed at Cluster & Network Level

First Tuning Process (2/2)

DIVA

Ec/Io

Best SC

Active set Size

Neighbor list tuning

DataLogging +

Processingsw

Corrective actions tobe performed

T t D i S ifi ti


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Test Drive Specifications Cell Shakedown

The drive routes for shakedown are defined as circles around the cell at

approximately 30 percent of the expected cell coverage area.

Purpose: to test call setup in each cell, handoffs (softer) between cells and to verify antenna

orientation, Primary Pilot EC/N0 (PCPICH EC/N0), scrambling code allocation for each sector

according to the RF design and neighbor list coherence with engineering requirements. UE

transmitted power will be analyzed to double-check possible reception cabling problems.

Equipment: Trace Mobile RF Scanner

Call type: voice call; ping.

Data collected: PCPICHEC/N0, UE transmitted power, DL carrier RSSI, Events (mapping

with rrc messages - rrc Established, Call setup, Call Established, Radio Link Addition &

Deletion)

Cell Shakedown Drive


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Purpose:to determine the actual pilot coverage for each cluster and solve the main RF

propagation issues (pilot shoot-up, pilot pollution, scrambling code overlap...) and neighbor list

estimation.

Equipment:Trace Mobile - Pilot scanner

Applications:none

Data collected:Scrambling code analysis (Ec/N0, Ec, RSSI), top-N analysis with a window at 12.

Analyses:Per-PCPICH coverage; Best PCPICH coverage; 2nd, 3rd, 4th, 5th, 6th PCPICH coverage;

Number of PCPICH over a given Ec/N0 (12dB - RF design warranty area)

Test Drive Specifications (1/2) Cluster/Network Optimization



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Purpose: Mainly insure the RF coverage control and neighbor list tuning (antenna

azimuths, tilts, neighbor list tuning)

Process: each call is setup, hold during the time and released; mobile originating and

mobile terminating for voice; mobile originating only for data.

Applications: voice call; FTP over several RABs.

Data collected: Ec/N0, UE transmitted power, DL transmitted code power, average

number of radio links.

Test Drive Specifications (2/2) Cluster/Network Optimization

Radio Verification DRIVE


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Agenda






Tools

Some Real examples

Lessons Learnt


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RF Scanner to collect the data- Initially it is necessary to perform pure

RF measurements so that we can take a real picture of the coverage

quality.

Agilent Viper, Anritsu, ...

Diva (Nortel Propietary), ...

Test Mobile- After a basic RF coverage quality has been implemented,

call processing measurements should be included to get closer to the

end customer perception

Nemo, Tems, CAIT, X-CAL, ...

RFO (Nortel Propietary), Actix, X-CAP

RNC Traces are very useful support for Call processing Optimization

Tools to be used

Both types of tools are complementary, cannotwork only with one type


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Viper Agilent E7476A The W-CDMA Receiver is the Agilent E6455C Digital Receiver

with the E7476A Network Optimization Platform.

Four different modes are available on the receiver:

Scrambling Code Analyzer [Top N, User List, P-SCH]

CPICH Ec/Io

Top N Ec/Io (SC reported regardless of any neighbor list),

Primary and Secondary SCH trace (Ec/Io, Ec),

RSSI (Io),

CPICH RSCP (Ec),

CW (Carrier Wave) Power Measurements,

Channel Power Measurements,

Spectrum Measurements


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Diva Agilent Post-processing

Nortel is using the proprietary DIVA Agilent post-processing tool to analyze and post-process the data collected from

the Agilent RF Receiver.

Source Data

Text file export from the Agilent E7476Adata collection software (Top-N files in Scrambling Code Analyzer mode) containing RSSI,

Ec/Io, SC, geographical coordinates, time stamp.

DRF files used for Site Database, to ease the display of site information and for neighbor list tuning (Site, FDDCell, AntennaSystem,

FDDNeighbouringCell DRF files)

Maps

Any geographical information readable by MapInfo (e.g, tabs and tiffs)

All maps displayed against background of highways, geographic features, etc.

User definable resolution for Geographic and Temporal binning of data.

The key analysis screens that are being used are

System Map: Best Ec/No, number of cells in active set, EC/No 2nd 3rd ... Server, potentially RSSI.

SC plotter: Ec/No in a sector level analysis

Delta tool module

Neighbor List Tuner


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RF Scanner vs Call processing

RF Optimization

Activity

Using Call

Processing +Processing Sw

Using RF Scanner

+ DIVA

Confirm coverage UE TX power Estimate with DL RSSI

Assess signal

quality

Best server Ec/No Best server Ec/No

Assess areas of

excessive handoff

UE active set Number of SCs meeting

given threshold criteria

Tune neighbor lists Conclude from call dropanalysis

Analysis of Measurement

Report messages

Add SCs that meet

threshold criteria but arent

in current neighbor list

Call Drop/Failed

Access analysis

Detailed message and

parametric info analysis

N/A

A huge progress on RF Coverage Control and Neighbor List Tuning, can be

done with scanner measurements (no need call processing).


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WCDMA RF Optimizer - Features

Other

Features

Failure Mode

Analysis

CoverageAnalysisDelta Plot Geographic plots of Parametric Data (forward & reverse links)

Call Statistics (Drop Calls, Access Failures) Synchronized Call Trace Screens Graphs of Parametric Data (forward & reverse links)

SC Plotter

Neighbor List Tuner Search Window Analysis (Active & Neighbor Set) Quality Analysis (Markov, Voice, per rate type)

DRF Editor (Network Configuration File) Soft Handoff Statistics (by handoff type, Avg. CEs / user, Avg RF Links / user)

Example of a Current Network Test


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Example of a Current Network Test

100 Sites Intensively RFOptimized.

>150 sectors used overdrive route, interferencefrom total cluster of 300

sectors.

253 Voice or PS data callsmade. 25000 Call Secondsof DCH occupancy.

Call Traces collected from

Network and UE Call drop rate referenced

to 90 second hold time


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Measurement Control Failure Example Dcch MEASCTRL remove[ 1 2 3 4 7 11 12 13 ] res( 0=73 5=35 6=36 8=47 9=57 10=74 14=23+ 15=24+16=34+ 17=55+ 18=56+ 19=68+ 20=72+)02:17:08.126 adr_ < Dcch :rrcMeasControlFailure

RrcActSetUpd del[ 73]

02:17:08.573 dlr_ > Dcch ActiveSetUpdate DEL[ 73]

02:17:08.615 dlr_ ASETUD f= 2152.2 [r35,]

02:17:52.808 dlr_ UE Status: Rssi=-59.2 UeTx=-12.4 Bler1=3.96% FingSC > 57/ -12.6,


02:18:02.810 dlr_ UE Status: Rssi=-48.8 UeTx=-23.0 Bler1=0% FingSC > 57/ -6.3,





!! CALL DROP_1 RRC=0 Symptom = Covg OK, Bad EC/NO !!Nbr Srch Fail Drop + MeasCtrlFail

02:18:19.778 dlr_ UE Status: FingSC >

02:18:20.353 idle > Bcch sfn=1033 systemInformationBlockType3 Cellid=27156 =SC 56

02:18:20.479 idle ASETUD f= 2152.2 [r56,]

02:18:20.479 idle NBR PKT []

02:18:20.671 idle > Bcch sfn=1049 systemInformationBlockType3 Cellid=27156 =SC 56

Neighborlist Update Fails

Causing UE not to find Neighbor

SC56 and drop due to bad ec/io

50 seconds later


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Agenda






Tools

Some Real examples

Lessons Learnt


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Some Real Examples of UMTS

optimization

Pilot Pollution optimization

Coverage optimization

Example of cluster tuning


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Example of Pilot pollution

Active set size for a cluster

Pilot pollution (> 3 way handover ) SW sector 152


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Example of Pilot pollution

Active set size after reazimuth of sector 152

Reduced pillot polution in the area


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Example of coverage control Ec/Io sector 136

Excess coverage for this sector


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Example of coverage control Down tilt of sector 136

Overspray substantially reduced

Initial Network Tuning Project


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g j

Overview (1/2)

TEAM I TEAM II

Sites to apply Cell Shakdown = 39

TUNING (CORE) = 30

ANEL_AUX = 18

Cluster I

# of sites = 25

# of sites (Core) = 11

# of sites (Cell Shakedown) = 18

Cluster II

# of sites = 23

# of sites (Core) = 19# of sites (Cell Shakedown) = 21

Cluster Tuning RF Coverage Control


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Change Antenna Orientation 18 SectorsChange Electrical tilt 15 SectorsChange Mechanical tilt 11 Sectors

Change Antenna Orientation 1 SectorsChange Electrical tilt 9 SectorsChange Mechanical tilt 6 SectorsChange Antenna Height 1 sectorSector splitt 1 sector

Change Antenna Orientation 4 SectorsChange Electrical tilt 5 SectorsChange Mechanical tilt 5 Sectors

# of Sites 48

# of Sectors 141

Universe

# of Sites 27 56%

# of Sectors 44 31%

HW work Orders

# of Sectors with Azimuths Changes 25 18%

# of Sectors with Electrical Tilt 26 18%# of Sectors with Mechanical Tilt 21 15%

HW work Orders

# of Sectors with Electrical Tilt 29 work orders

# of Sectors with Mechanical Tilt 22 work orders

# of Sectors with 1 work type 23# of Sectors with 2 work type 12

# of Sectors with 3 work type 7

# of Sectors with 4 work type 2



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Ec/No Ranges (dB) before Mai-22 Mai-22 after after

-6 to 0 58% 56% 62% 57% 61%

-8 to 6 25% 26% 22% 25% 21%

-10 to 8 11% 11% 10% 11% 9%

-12 to -10 3% 3% 3% 4% 3%

-15 to 12 1% 1% 2% 1% 1%

-30 to -15 0% 0% 1% 0% 1%

UEScanner

CPICH Ec/Io

After



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Number of cells in Active Set before Mai-22 Mai-22 After After

1 47% 47% 41% 47% 42%

2 34% 34% 34% 34% 33%

3 14% 15% 16% 14% 16%

4 4% 4% 6% 4% 7%

5 1% 1% 3% 1% 2%

6 0% 0% 1% 0% 1%

7 0% 0% 0% 0% 0%

9 0% 0% 0% 0% 0%

UEScanner

Active Set Size

After

Zoom on bad EC/Io Problem


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Problem: Interference; Low signal Level.

Objective: Find a best server

Solution: 1stReorientation of 123A; downtilt of 231C, 23C 45 B.

2nd Remove downtilt of 123A

3rdTurn off the sector 123 A and reorientation of 45 B

Obs.: MINIMIZED. The only solution is a new site for +/- 200m (micro site?)

SPOT2SPOT2



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Problem: Interference; Low signal Level.

Objective: Find a best serverSolution: 1stDowntilt of 67 C and 58 B.

2ndAdition of a 3rd sector in split on 120

Obs.: SOLVED

SPOT3SPOT3


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Problem: High active set size.Objective: Reduce the active set size.

Solution: 1st Downtilt of 134 C and 37 C.

Obs.: SOLVED.

SPOT9SPOT9



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Examples on Application metrics

Evolution

Cluster 4* Start Inter Final

Mean Holding Time

(continuous Calls)

11,4 min 22,7 min 38,4 min

Dropped Call Rate Voice 13,2% 6,2% 2,8%

Dropped Call Rate PS 384 18,3% 9,3% 5,1%

Call Setup Success Voice 83,2% 91,2% 95,1%

Call Setup Success PS 384 80,1% 93,2% 94,3%

Successful Calls Voice 70% 85% 92,3%

Successful Calls PS 384 61,8% 83,9% 89,2%

* Values based on low number of samples (high SD)


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Tuning Mobility 3G-2G

UMTS is being initially deployed as coverage islands relying on

roaming to 2G networks to complete coverage layer

An interlayer mobility strategy is needed to ensure minimum

impact to the customerwhen moving out from 3G Coverage

It is important to take a good picture of the rf quality of the 2G

network so that we can tune the 2G neighbor list

Identify properly the sites in the 3G coverage boundaries

Generate a best server plot of the 2G area

Define the neighbor list accordingly

Compressed mode parameters need to be carefully optimized

A d


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Agenda



RF Optimization

Optimization Stages



Tools

Some Real examples

Lessons Learnt

Link Budget Results applied in Real Project


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Link Budget Results applied in Real Project

CPICH RSCP = CPICH Ec (dBm) Received Signal Code Power on one

channelisation code measured on the Primary CPICH.

CPICH power 35 dBm

feeders loss 3,5 dB

antenna gain 17,5 dB EiRP = 49

EiRP = CPICH power -feeder loss + anten

dBm

Minimum Receive Level (Dense Urban) = EiRP - Max Pathloss

Speech 12,2 CS 64 PS 64 PS 144 PS 384

Maximum Path Loss 126,3 124,5 125,9 123 119 Available Reverse Link Budget

Minimum Receive Level -77,3 -75,5 -76,9 -74 -70

Maximum Path Loss 127,4 125,6 127 124,1 120,1 Available Reverse Link Budget

Minimum Receive Level -78,4 -76,6 -78 -75,1 -71,1

Maximum Path Loss 136,9 134,6 136,6 133,7 129,5 Available Reverse Link Budget

Minimum Receive Level -87,9 -85,6 -87,6 -84,7 -80,5

Urban Environment - Indoor

Suburban Environment - Indoor

Dense Urban Environment - Indoor

Validation of the Link Budget


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Validation of the Link Budget

EC values (dBm) before after

-50 to 20 4% 4%

-60 to 50 15% 15%

-75 to 60 40% 36%

-85 to 75 25% 26%

-95 to 85 12% 13%

-120 to 95 1% 3%

CPICH RSCP > -78 (PS 64 was design objective) in more than 80% with 9 missing sites...

R les Generated after se eral Isolation


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Rules Generated after several Isolation

Measurements

Area 1 is forbidden

Area 2 azimuths 0 to 180



Area 5 : mix decoupling area (vertical + horizontal)

N.B. : The large circle represent the margin for H90 antennas; and the bold line the limit between area 2&5 forthese antennas

GSM 1800 60 dB of horizontal isolation

chart

Dual Band 60 dB of horizontal isolation

chart

S l f t l t l ti


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Some examples of antenna layout evolutionObject ive is to keep number of antennas

Rx/ Tx Rx/Tx ou RxEricsson RBS200 c/duplex

Ericsson RBS2202Lucent RBS2000/6 HybridLucent RBS2000/12 Hybrid

Rx/Tx Rx/Tx

UMTS

Rx/ Tx Rx/Tx ou Rx

Ericsson RBS200 c/duplexEricsson RBS2202Lucent RBS2000/6 HybridLucent RBS2000/12 Hybrid

Tma

Tma

Tma

Tma

Tma

Tma

GSM 900 GSM 900Rx/Tx Rx/Tx

UMTS

Rx/ Tx Rx/Tx ou RxEricsson RBS200 c/ duplexEricsson RBS2202Lucent RBS2000/6 Hybr idLucent RBS2000/ 12 Hybrid

Rx/ Tx Rx/Tx ou RxEricsson RBS200 c/ duplexEricsson RBS2202Lucent RBS2000/6 Hybr idLucent RBS2000/ 12 Hybrid

Tma

Tma

Tma

Tma

Tma

Tma

GSM 900 GSM 900

Rx/Tx Rx/TxUMTS

Rx/Tx Rx/Tx1800

Tm

a

Tm

a

Rx/ Tx Rx/Txou Rx

Ericsson RBS200 c/ duplex

Ericsson RBS2202Lucent RBS2000/6 Hybr id

Lucent RBS2000/12 Hybr id

Rx/ Tx Rx/Txou Rx

Ericsson RBS200 c/ duplexEricsson RBS2202Lucent RBS2000/6 Hybr id

Lucent RBS2000/12 Hybr id

Rx/Tx Rx/Tx1800

Tm

a

Tm

a

Tm

a

Tm

aTm

a

Tm

a

Tm

a

Tm

a

GSM 900GSM 900GSM 1800 GSM 1800

Rx/Tx Rx/TxouRxEricsson RBS200 c/dupl exEricsson RBS2202Lucent RBS2000/6 Hybr idLucent RBS2000/12 H ybrid

Rx/Tx Rx/Tx1800

Tm

a

Tm

a

Tm

a

Tm

a

Rx/Tx Rx/TxUMTS

Rx/Tx Rx/Tx1800

Rx/Tx Rx/Txou RxEricsson RBS200 c/dupl exEricsson RBS2202Lucent RBS2000/6 H ybridLucent RBS2000/12 Hybrid

Tm

a

Tm

a

Tm

a

Tm

a

Tm

a

Tm

a

GSM 900 GSM 900

GSM 1800 GSM 1800

Some Optimization Conclusions


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According to Nortels original recommendations, based on CDMA

experience, the following items were confirmed:

Antenna Types Electrical Tilt & Horizontal Beamwidth

Antenna Configuration (Avoid 3 sectors within 180)

Importance of HW config high correlation with the QoC; From 40 up to 50% of HW changes during

optimization

Importance of Site Selection a supplementary effort when Acquisition to match the objectives /

requirements even the main driver is to go for a simple design

Troubleshoot an Area A new site is not always a solution (macro & microcellular approach)

Nominal cell Design Measured coverage compliant to original RF design; All

missing sites (Greenfield & 2G InPlan) were concluded to be relevant.

2G Sites needs to be specially analyzed If the level of interference is high,

is better not to build it than to remove it; some sites there is no way to control its

coverage...

p

Conclusions


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Conclusions

The variables that influence the behavior of the system are excessive,

the number of assumptions that would need to be performed makes any

study be just a guess.... The only way of finding results is reality.

Nortel has successfully designed and optimized UMTS networks and is

gathering real field experience to be able to drive the market

requirements.

WCDMA system is significantly more sensitive to interferences than

GSM, it is very important to perform a good RF design and Optimization

to achieve the best performance

Most of the advices coming from the CDMA experience are really helping

us to solve the problems we are finding on the field.

Nortel Networks is committed to UMTS and is willing to help you in

successful implementations of UMTS ...


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A ti S t Si ft th h


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Active Set Size after the changes

08 2e europe rf experience sharing 2%2e0

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