Huawei-WCDMA Capacity Planning

WCDMA Capacity Dimensioning

WCDMA System Capacity WCDMA System Capacity CharacteristicsCharacteristics

WCDMA System Capacity WCDMA System Capacity CharacteristicsCharacteristics

WCDMA is a self-interfering systemWCDMA is a self-interfering system (Same (Same carrier for all the users).carrier for all the users).

WCDMA system capacity is closely related to WCDMA system capacity is closely related to coveragecoverage (Reverse Relation) (Reverse Relation)

WCDMA network capacity has the soft WCDMA network capacity has the soft capacity featurecapacity feature

The capacity planning of the WCDMA The capacity planning of the WCDMA network is performed under a certain traffic network is performed under a certain traffic modelmodel

Course ObjectiveCourse Objective Course ObjectiveCourse Objective

Grasp the parameters of 3G Grasp the parameters of 3G traffic modeltraffic model

Understand the factors that Understand the factors that restrict the WCDMA network restrict the WCDMA network capacitycapacity

Understand the methods and Understand the methods and procedures of estimating procedures of estimating multi-service capacitymulti-service capacity

Understand the key Understand the key technologies for enhancing technologies for enhancing network capacitynetwork capacity

After this session, you will:After this session, you will:

Contents of CourseContents of Course Contents of CourseContents of Course

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Chapter 1 Traffic Model

Chapter 2 Uplink capacity analysis

Chapter 3 Downlink capacity analysis

Chapter 4 Multi-service capacity estimation

Chapter 5 Network estimation procedure

Chapter 6 Capacity enhancement

technologies

Chapter 1 Traffic ModelChapter 1 Traffic Model Chapter 1 Traffic ModelChapter 1 Traffic Model

1 Overview of traffic model1 Overview of traffic model

2 CS traffic model2 CS traffic model

3 PS traffic model diagram3 PS traffic model diagram

4 PS traffic model 4 PS traffic model

parametersparameters

Service OverviewService Overview Service OverviewService Overview

The WCDMA system supports multiple The WCDMA system supports multiple servicesservices Variable-rate services Variable-rate services Combined servicesCombined servicesHigh-speed data packet servicesHigh-speed data packet servicesAsymmetrical services different Rates at the Asymmetrical services different Rates at the

UL&DL.UL&DL.Large-capacity and flexible service bearingLarge-capacity and flexible service bearing

Qos TypeQos Type Qos TypeQos Type

Re

al-tim

e ca

tego

ry

Re

al-tim

e ca

tego

ry

conversatioconversationalnal

It is necessary to maintain the time It is necessary to maintain the time relationship between the information relationship between the information entities in the stream. Small delay entities in the stream. Small delay tolerance, requiring data rate tolerance, requiring data rate symmetrysymmetry . .

Voice Voice service, service, videophonevideophone

StreamingStreaming

Typically unidirectional services, high Typically unidirectional services, high requirements on error tolerance, high requirements on error tolerance, high requirements on raterequirements on rate

Streaming Streaming multimediamultimedia

No

n rea

l-time

N

on

real-tim

e

cate

go

ryc

ateg

ory

InteractiveInteractive

Request-response mode, data Request-response mode, data completeness must be maintained. completeness must be maintained. High requirements on error tolerance, High requirements on error tolerance, lower requirements on delay tolerancelower requirements on delay tolerance

Web page Web page browse, browse, network network gamegame

BackgroundBackground

Data completeness should be Data completeness should be

maintained. Small delay restriction, maintained. Small delay restriction,

requiring errorless transmissionrequiring errorless transmission

Background Background download of download of EmailEmail..

Objectives of Setting Up Traffic Objectives of Setting Up Traffic ModelModel

Objectives of Setting Up Traffic Objectives of Setting Up Traffic ModelModel

In order to determine the system configuration, we need to In order to determine the system configuration, we need to

determine the call capacity of the air interface first. determine the call capacity of the air interface first.

In the data service, different transmission model will In the data service, different transmission model will

generate different system capacities. generate different system capacities.

We need to set up an expected data transmission model We need to set up an expected data transmission model

of the customer so that we can plan the network properly. of the customer so that we can plan the network properly.

In order to set up a correct model, the operator should In order to set up a correct model, the operator should

provide some statistic parameters as a reference.provide some statistic parameters as a reference.

Traffic model is a means of researching Traffic model is a means of researching

the capacity features of each service type the capacity features of each service type

and the QoS expected by the users who and the QoS expected by the users who

are using the service from perspective of are using the service from perspective of

data transmission.data transmission.

In the data application, the user In the data application, the user

behaviour research mainly forecasts the behaviour research mainly forecasts the

service types available from the 3G, the service types available from the 3G, the

number of users of each service type, number of users of each service type,

frequency of the users in using the frequency of the users in using the

service, and the distribution of the users service, and the distribution of the users

in different regions. in different regions.

Traffic Model

System Configuration

User behaviour

Service Pattern

Traffic Model

Results

The Contents of Traffic Model

Typical Service Features DescriptionTypical Service Features Description Typical Service Features DescriptionTypical Service Features Description

Typical service features include the Typical service features include the following feature parameters:following feature parameters: User type (indoor, inside vehicle, outdoor)User type (indoor, inside vehicle, outdoor) User’s average moving speedUser’s average moving speed Service TypeService Type Uplink and downlink service ratesUplink and downlink service rates Spread factorSpread factor Signal delay requirements of the serviceSignal delay requirements of the service

QoS requirements of the serviceQoS requirements of the service







CS Traffic ModelCS Traffic Model CS Traffic ModelCS Traffic Model

Voice service is representative of CS services. Voice service is representative of CS services.

Voice user arrival takes on the Poisson Voice user arrival takes on the Poisson

distribution. Its time interval takes on the distribution. Its time interval takes on the

exponent distribution. exponent distribution. Key parameters of the model: Key parameters of the model:

Penetrating ratePenetrating rate BHCABHCA Mean busy-hour call attemptsMean busy-hour call attempts Mean call duration (s)Mean call duration (s) Activation factorActivation factor Mean rate of service (kbps)Mean rate of service (kbps)

CS Traffic Model ParametersCS Traffic Model Parameters CS Traffic Model ParametersCS Traffic Model Parameters

Mean busy-hour traffic (Erlang) per user = Mean busy-hour traffic (Erlang) per user =

BHCA * mean call duration /3600BHCA * mean call duration /3600

Mean busy hour throughput per user (kbit) Mean busy hour throughput per user (kbit)

(G) = BHCA * mean call duration * activation (G) = BHCA * mean call duration * activation

factor * mean ratefactor * mean rate

Mean busy hour throughput per user (bps) Mean busy hour throughput per user (bps)

(H) = mean busy hour throughput per user * (H) = mean busy hour throughput per user *

1000/36001000/3600







PS Traffic Model

The most frequently used model is the packet service The most frequently used model is the packet service

session process model described in ETSI UMTS30.03.session process model described in ETSI UMTS30.03.







PS Traffic ModelPS Traffic ModelPS Traffic ModelPS Traffic Model

Data Burst Data Burst Data Burst

Packet Call

Session

Packet Call Packet Call

Downloading Downloading

Active Dormant Dormant Active

Traffic model

PS Traffic Model Parameters

Packet Call Num/SessionPacket Call Num/Session

Packet Num/Packet CallPacket Num/Packet Call

Packet Size(bytes)Packet Size(bytes)

Reading Time (sec)Reading Time (sec)

Typical Bear Rate(kbps)Typical Bear Rate(kbps)

BLERBLER

Parameter Determining

The basic parameters in the traffic model are determined in the The basic parameters in the traffic model are determined in the

following ways:following ways:

Obtain numerous basic parameter sample data from the Obtain numerous basic parameter sample data from the

actually operating network. actually operating network.

Obtain the probability distribution of the parameters Obtain the probability distribution of the parameters

through processing of the sample data.through processing of the sample data.

Take the distribution most proximate to the standard Take the distribution most proximate to the standard

probability as the corresponding parameter distribution probability as the corresponding parameter distribution

through comparison with the standard distribution function.through comparison with the standard distribution function.

Typical Bear Rate(kbps)Typical Bear Rate(kbps) ：：

Bear rate is variable in the actual transmission process.Bear rate is variable in the actual transmission process.

BLER:BLER:

In the PS service, when calculating the data transmission In the PS service, when calculating the data transmission

time, the retransmission caused by erroneous blocks should time, the retransmission caused by erroneous blocks should

be considered. Suppose the data quantity of service source be considered. Suppose the data quantity of service source

is N, the air interface block error rate is BLER, the total is N, the air interface block error rate is BLER, the total

required data quantity to be transmitted via the air interface required data quantity to be transmitted via the air interface

is:is:

PS Traffic Model Parameters

NBLER

BLERNBLERNBLERNBLERNN n *1

1**** 32

User behaviour

Penetrating RatePenetrating Rate

BHSABHSA

User Distribution (High, User Distribution (High, Medium, Low end)Medium, Low end)

PS User Behaviour Parameters

PS User Behaviour Parameters

Penetrating RatePenetrating Rate ：：

The percentage of the users that activates this The percentage of the users that activates this

service to all the users registered in the network.service to all the users registered in the network.

BHSABHSA ：： The times of single-user busy hour sessions The times of single-user busy hour sessions

of this serviceof this service

User DistributionUser Distribution (High, Medium, Low end)(High, Medium, Low end)

The users are divided into high-end, mid-end and The users are divided into high-end, mid-end and

low-end users. Different operators and different low-end users. Different operators and different

application situations will have different user application situations will have different user

distributions.distributions.

Session Session traffic volumetraffic volume （（ ByteByte ））：： Average traffic Average traffic

of single session of the serviceof single session of the service

Data transmission time Data transmission time (s)(s) ：： The time in a single The time in a single

session of service for purpose of transmitting session of service for purpose of transmitting

data.data.

Holding TimeHolding Time （（ ss ））：： Average duration of a Average duration of a

single session of servicesingle session of service

PS Traffic Model Derivative Parameters

eTypicalRat

fficVolumeSessionTra

BLERsissionTimeDataTransm

1000/8**

1

1)(

)(

Re*)1(

sissionTimeDataTransm

adingTimeionNumPerSessPacketCall

eHoldingTim

)/(*)/(*)( SessionNumPacketCallPacketCallPacketNumPacketSizefficVolumeSessionTra

Activation factor:Activation factor: The weight of the time of The weight of the time of

service full-rate transmission among the service full-rate transmission among the

duration of a single session. duration of a single session.

Busy hour throughput per user (Kbit):Busy hour throughput per user (Kbit):

eHoldingTim

issionTimeDataTransmorActiveFact

1000/8**/ fficVolumeSessionTraBHSAuserroughputBusyHourTh

PS Traffic Model Derivative Parameters

Traffic Model ExampleTraffic Model Example Traffic Model ExampleTraffic Model Example VOD VOD

mobile mobile video video

streamsstreams

PenetratiPenetrating rateng rate

BHSABHSABusy Hour Busy Hour

Throughput/Throughput/user (kbit)user (kbit)

Typical Typical bear bear rate rate

(kbps)(kbps)

BLERBLERActivatiActivati

on on factorfactor

UplinkUplink 22.0%22.0% 0.1000.100 2.3042.304 88 10%10% 0.17980.1798

DownlinkDownlink 22.0%22.0% 0.1000.100 102.528102.528 6464 10%10% 1.00001.0000

VOD VOD mobile mobile video video

streamsstreams

Packet Packet Call Call

Num/SesNum/Sessionsion

Packet Packet Num/PaNum/Packet Callcket Call

Packet Size Packet Size (bytes)(bytes)

ReadinReading Time g Time (sec)(sec)

SessioSession n traffic traffic volumevolume

ByteByte

Holding Holding TimeTime

UplinkUplink 22 33 480480 14.60014.60000

28802880 17.800017.8000

DownlinkDownlink 11 267267 480480 0.00000.0000 128161281600

17.800017.8000

)3600

(_

orActiveFactredRateTypicalBea

nEviromentApplicatioderTypicalroughputUnBusyHourThgRatePenetratinUserOfDiffrentPercentageErlangData

QuestionsQuestions QuestionsQuestions

What are the two parts that make What are the two parts that make up the traffic model? up the traffic model?

What are the main parameters of What are the main parameters of the CS traffic model? the CS traffic model?

What are the main parameters of What are the main parameters of the PS traffic model? the PS traffic model?

What is the formula for calculating What is the formula for calculating the equivalent Erlang of data the equivalent Erlang of data service?service?

Summary of This ChapterSummary of This Chapter Summary of This ChapterSummary of This Chapter

This chapter deals with the topic of traffic This chapter deals with the topic of traffic modelmodel

Main parameters of traffic model for CS service Main parameters of traffic model for CS service Structure and main parameters of PS traffic Structure and main parameters of PS traffic

model, and the corresponding derivative model, and the corresponding derivative parameters parameters

Method of calculating equivalent Erlang of data Method of calculating equivalent Erlang of data serviceservice


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Basic Principles

The radio system capacity is decided by uplink and downlink. When planning the capacity, we must analyze from both uplink and downlink perspectives.

In the WCDMA system, all the cells share the same spectrum, which is conducive to improving the WCDMA system capacity. However, for reason of co-frequency multiplexing, the system incurs interference between users. This multi-access interference restricts the capacity in turn.

Basic Principles—Interference Basic Principles—Interference AnalysisAnalysis

Basic Principles—Interference Basic Principles—Interference AnalysisAnalysis Interference restriction model

ITOT = Iown + Iother + PN + T

IIown own Interference from the users of this cellInterference from the users of this cell

IIother other Interference from the users of adjacent cellInterference from the users of adjacent cell

PPN N Noise floor of receiverNoise floor of receiver

T T Outside interferenceOutside interference (can be neglected)

Power restriction model

PTOT = Ppil + Psync + Ppag + Ptraf + Pother

Ppil Ppil Pilot channel powerPilot channel power

Psync Psync Synchronization channel powerSynchronization channel power

Ppag Ppag Paging channel powerPaging channel power

Ptraf Ptraf Traffic channel powerTraffic channel power

Pother Pother Other channel powerOther channel power

NotherownTOT PIII

Uplink Interference Analysis—Uplink Uplink Interference Analysis—Uplink Interference CompositionInterference Composition


IIownown ：： Interference from the users of this cellInterference from the users of this cell

IIotherother ：： Interference from users of adjacent cellInterference from users of adjacent cell

PPNN ：： Noise floor of the receiverNoise floor of the receiver

Receiver noise floor Receiver noise floor PPNN

P PNN = 10lg(KTW) = 10lg(KTW) ＋＋ NFNF– KK ：： Boltzmann constant, = 1.38Boltzmann constant, = 1.38××10-23 J/K10-23 J/K

– TT ：： Kelvin temperature, normal Kelvin temperature, normal temperature: 290 Ktemperature: 290 K

– WW ：： Signal bandwidth, WCDMA signal Signal bandwidth, WCDMA signal bandwidth 3.84MHzbandwidth 3.84MHz

– 10lg(KTW) = -108dBm/3.84MHz10lg(KTW) = -108dBm/3.84MHz

NF = 3dB (typical value of macro cell BTS)NF = 3dB (typical value of macro cell BTS) PPNN = 10lg(KTW) + NF = -105dBm/3.84MHz = 10lg(KTW) + NF = -105dBm/3.84MHz



IIownown : :Interference from users of this cellInterference from users of this cell Interference that every user must overcome:Interference that every user must overcome: IITOTTOT - P - Pjj

– Pj is the receiving power of the user jPj is the receiving power of the user j

Under the ideal power control :Under the ideal power control :

Hence, Pj:Hence, Pj:

The interference from users of this cell is the sum of power of The interference from users of this cell is the sum of power of all the users arriving at the receiverall the users arriving at the receiver::

jjTOT

j

jvR

W

I

PNoEb

1/

N

jown PI1



total

jjj

j IW

RVP

IIotherother : :Interference from users of adjacent cellInterference from users of adjacent cell The interference from users of adjacent cell is difficult to The interference from users of adjacent cell is difficult to

analyze theoretically, because it is related to user analyze theoretically, because it is related to user distribution, cell layout, and antenna direction diagram.distribution, cell layout, and antenna direction diagram.

Adjacent cell interference factorAdjacent cell interference factor

When the users are distributed evenlyWhen the users are distributed evenly – For omnidirectional cells, the typical value of adjacent cell For omnidirectional cells, the typical value of adjacent cell

interference factor is 0.55interference factor is 0.55

– For the 3-sector directional cell, the typical value of adjacent For the 3-sector directional cell, the typical value of adjacent cell interference factor is 0.65cell interference factor is 0.65

own

other

I

Ii



Define

Then N

N

jTOTTOT PLiII 1

1

Uplink Interference AnalysisUplink Interference Analysis Uplink Interference AnalysisUplink Interference Analysis

N

NTOTjjjb

NotherownTOT

PW

IRvNEi

PIII

1

0/1

W

RvNEL jjjb

j

0/

Obtain

N

j

NTOT

LiPI

1

11

1

Supposed that:Supposed that: All the users are 12.2 All the users are 12.2

kbps voice users, the kbps voice users, the demodulation threshold demodulation threshold Eb/No = 5dBEb/No = 5dB

Voice activation factor Voice activation factor vj vj = 0.67= 0.67

Adjacent cell Adjacent cell

interference factorinterference factor

i = 0.55i = 0.55

Uplink Interference AnalysisUplink Interference Analysis Uplink Interference AnalysisUplink Interference Analysis

Uplink Interference Analysis—Uplink Uplink Interference Analysis—Uplink Load FactorLoad Factor

Uplink Interference Analysis—Uplink Uplink Interference Analysis—Uplink Load FactorLoad Factor

Define the uplink load factorDefine the uplink load factor

When the load factor is 1When the load factor is 1, , IITOTTOT is infinite, and the is infinite, and the

corresponding capacity is called “threshold corresponding capacity is called “threshold capacity”.capacity”.

Under the above assumption, the threshold Under the above assumption, the threshold capacity is approx. capacity is approx. 96 users.96 users.

N

jjjbN

jUL W

RvNEiLi

1

0

1

/11

Uplink Interference Analysis—Load Uplink Interference Analysis—Load Factor and InterferenceFactor and Interference

Uplink Interference Analysis—Load Uplink Interference Analysis—Load Factor and InterferenceFactor and Interference

According to the abovementioned relationship, the According to the abovementioned relationship, the noise will rise:noise will rise:

1

1 1

11 1

TOTN

N ULj

INoiseRise

P i L

50% Load — 3dB60% Load — 4dB75% Load — 6dB

The abovementioned theoretic analysis uses the The abovementioned theoretic analysis uses the

following simplifying explicitly or implicitly:following simplifying explicitly or implicitly:

No consideration of the influence of soft handoverNo consideration of the influence of soft handover

– The users in the soft switch state generates the interference which is The users in the soft switch state generates the interference which is

slightly less than that generated by ordinary users.slightly less than that generated by ordinary users.

No consideration of the influence of AMRC and hybrid serviceNo consideration of the influence of AMRC and hybrid service

– AMRC reduces the voice service rate of some users, and makes them AMRC reduces the voice service rate of some users, and makes them

generate less interference, and increases the number of users generate less interference, and increases the number of users

supportable by the system. (The cost is the call quality of such users supportable by the system. (The cost is the call quality of such users

will be deteriorated)will be deteriorated)

– Difference services have different data rates and demodulation Difference services have different data rates and demodulation

thresholds. In principle, we can use the foregoing method for analysis, thresholds. In principle, we can use the foregoing method for analysis,

but it will complicate the calculation process. but it will complicate the calculation process.

– Since the time-variable feature of the mobile transmission Since the time-variable feature of the mobile transmission

environment, the demodulation threshold even for the same service is environment, the demodulation threshold even for the same service is

time-variable.time-variable.

Uplink Interference Analysis—Uplink Interference Analysis—Limitation of the Current MethodLimitation of the Current Method


Ideal power control assumptionIdeal power control assumption – The power control commands of the actual The power control commands of the actual

system have certain error codes so that the system have certain error codes so that the power control process is not ideal, and reduces power control process is not ideal, and reduces the system capacitythe system capacity

Assume that the users are distributed evenly, Assume that the users are distributed evenly, and the adjacent cell interference is constantand the adjacent cell interference is constant

Considering the above factors, the system Considering the above factors, the system emulation is a more precise method:emulation is a more precise method:

– Static simulation: Monte_Carlo methodStatic simulation: Monte_Carlo method

– Dynamic simulationDynamic simulation




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Basic Principles—Interference Basic Principles—Interference AnalysisAnalysis

Basic Principles—Interference Basic Principles—Interference AnalysisAnalysis Interference restriction model

ITOT = Iown + Iother + PN + T

IIown own Interference from the users of this cellInterference from the users of this cell

IIother other Interference from the users of adjacent cellInterference from the users of adjacent cell

PPN N Noise floor of receiverNoise floor of receiver

T T Outside interferenceOutside interference

Power restriction model

PTOT = Ppil + Psync + Ppag + Ptraf + Pother

Ppil Ppil Pilot channel powerPilot channel power

Psync Psync Synchronization channel powerSynchronization channel power

Ppag Ppag Paging channel powerPaging channel power

Ptraf Ptraf Traffic channel powerTraffic channel power

Pother Pother Other channel powerOther channel power

NotherownTOT PIII

IIownown ：： Interference from the users of this cellInterference from the users of this cell

IIotherother ：： Interference from the users of Interference from the users of

adjacent adjacent

cellcell PPNN ：： Noise floor of the receiverNoise floor of the receiver

Downlink Interference Analysis—Downlink Interference Analysis—Downlink Interference CompositionDownlink Interference Composition


Receiver noise floor PNReceiver noise floor PN PPNN = 10lg(KTW) = 10lg(KTW) ＋＋ NFNF

– KK Boltzmann constant, = 1.38Boltzmann constant, = 1.38××10-23 J/K10-23 J/K

– TT Kelvin temperature, normal temperature Kelvin temperature, normal temperature 290 K290 K

– WW Signal bandwidth, WCDMA signal Signal bandwidth, WCDMA signal bandwidth 3.84MHzbandwidth 3.84MHz

– NF: NF: Receiver noise figureReceiver noise figure

10lg(KTW) = -108dBm/3.84MHz10lg(KTW) = -108dBm/3.84MHz NF = 7dB NF = 7dB （（ UE typical valueUE typical value ）） PPNN = 10lg(KTW) + NF = -101dBm/3.84MHz = 10lg(KTW) + NF = -101dBm/3.84MHz



IIownown : :Interference from users of this cellInterference from users of this cell The downlink users are identified with the mutually The downlink users are identified with the mutually

orthogonal OVSF codes. In the static propagation orthogonal OVSF codes. In the static propagation conditions without multi-path, no mutual interference conditions without multi-path, no mutual interference exists.exists.

In case of multi-path propagation, certain energy will In case of multi-path propagation, certain energy will be detected by the RAKE receiver, and become be detected by the RAKE receiver, and become interference signals. Define the interference signals. Define the orthogonal factor αorthogonal factor α to to describe this phenomenon. describe this phenomenon.

– In the formula, PT is a total transmitting power of In the formula, PT is a total transmitting power of BTS, which includes the dedicated channel BTS, which includes the dedicated channel transmitting power and the common channel transmitting power and the common channel transmitting powertransmitting power

1 Town jj

j

PI

PL

N

jCCHT PPP1



IIotherother:: Interference from users of adjacent cellInterference from users of adjacent cell The transmitting signal of the adjacent cell BTS The transmitting signal of the adjacent cell BTS

will cause interference to the users in the current will cause interference to the users in the current cell. Since the scrambles in use are different, such cell. Since the scrambles in use are different, such interference is non orthogonal.interference is non orthogonal.

Assume the service is distributed evenly, the Assume the service is distributed evenly, the transmitting power of all BTSs will be equal. transmitting power of all BTSs will be equal. k,j k,j In In the system, there are K adjacent cell BTSs, where the system, there are K adjacent cell BTSs, where path loss from the number k BTS to the user j is path loss from the number k BTS to the user j is PLPLk,j.k,j. Hence we obtain:Hence we obtain:

K

jkTjother PLPI

1 ,

1

下行干扰分析下行干扰分析 -- -- 下行干扰构成下行干扰构成下行干扰分析下行干扰分析 -- -- 下行干扰构成下行干扰构成

下行干扰分析下行干扰分析下行干扰分析下行干扰分析

N

K

jkT

j

Tj

NotherownTOT

PPL

PPL

P

PIII

1 ,

11

Suppose the power control is desired, we obtain

jjjTOT

j

j

j vR

W

I

PLP

EbvsNo1

Then

jjTOTjj

jj PLIvW

REbvsNoP

Because N

jCCHT PPP1

Then

jN

K

jk

jTTj

N

jj

jCCH

N

K

jkT

j

Tj

N

jjj

jCCH

N

jjTOTjj

jCCHT

PLPPL

PLPPv

W

REbvsNoP

PPL

PPL

PPLv

W

REbvsNoP

PLIvW

REbvsNoPP

1 ,1

1 ,1

1

1

11


Resolve PT to obtain

N

jj

jjj

N

jjj

jNCCH

T

vW

REbvsNoi

PLvW

REbvsNoPP

P

1

1

11

where ij is the adjacent cell interference factor of the user, defined as:

K

jk

jj PL

PLi

1 ,


According to the above analysis, we can According to the above analysis, we can define the downlink load factor:define the downlink load factor:

When the downlink load factor is 100%, the When the downlink load factor is 100%, the transmitting power of the BTS is infinite, and transmitting power of the BTS is infinite, and the corresponding capacity is called the corresponding capacity is called “threshold capacity”. “threshold capacity”.

As different from the theoretic calculation of As different from the theoretic calculation of uplink capacity, αj and ij in the downlink uplink capacity, αj and ij in the downlink capacity formula are variable related to user capacity formula are variable related to user position. Namely, the downlink capacity is position. Namely, the downlink capacity is related to the spatial distribution of the related to the spatial distribution of the users, and can only be determined through users, and can only be determined through system emulation. system emulation.

N

jj

jjjDL vW

REbvsNoi

1

1

Downlink Interference AnalysisDownlink Interference Analysis Downlink Interference AnalysisDownlink Interference Analysis

Parameter DL valueMCL macro (including antennaagain)

70 dB

Antenna gain (including losses) 11 dBiLog Normal fade margin 10 dBPC MODELLING#PC steps per snapshot > 150step size PC perfect PCPC error 0%HANDOVER MODELINGHandover threshold for candidatesetactive setChoice of cells in the active step

CombiningMaximum ratio

combiningNOISE PARAMETERSnoise figure 9 dBnoise power -99 dBm proposedTX POWERMaximum BTS power 43 dBmCommon channel power 30 dBmMaximum TX power speech 30 dBm

Parameter DL valuePower control range 25 dB

HANDLING of DOWNLINKmaximum TX power

USER DISTRIBUTIONRandom and uniformacross the network

non orthogonality factor macrocell 0.4COMMON CHANNELORTHOGONALITY

Orthogonal

DEPLOYMENT SCENARIO

MacrocellHexagonal with BTSin the middle of the

cellBTS type omnidirectionalCell radius macro 577 macro

# of macro cells> 19 with wrap

around technique)bit-rate speech 8 kbpsActivity factor speech 100%Multipath environment macro Outdoor microEb/N0 target 6.1 dB

Downlink Interference Analysis—Downlink Interference Analysis—Emulation Parameter SettingEmulation Parameter Setting

Downlink Interference Analysis—Downlink Interference Analysis—Emulation Parameter SettingEmulation Parameter Setting

Downlink Interference Analysis—Downlink Interference Analysis—Emulation ResultEmulation Result

Downlink Interference Analysis—Downlink Interference Analysis—Emulation ResultEmulation Result

When the transmitting power of the BTS is When the transmitting power of the BTS is 43dBm (20W), the supported maximum number 43dBm (20W), the supported maximum number of users is approx. 114.of users is approx. 114.

In order to ensure system stability, we do not In order to ensure system stability, we do not

allow the mean transmitting power of the BTS allow the mean transmitting power of the BTS to be more than 80% of the maximum to be more than 80% of the maximum transmitting power, namely, 42dBm. This way, transmitting power, namely, 42dBm. This way, the supported number of users is 112. the supported number of users is 112.

Downlink Interference Analysis—Downlink Interference Analysis—Emulation Result AnalysisEmulation Result Analysis

Downlink Interference Analysis—Downlink Interference Analysis—Emulation Result AnalysisEmulation Result Analysis

How to Control How to Control InterferenceInterference

How to Control How to Control InterferenceInterference

Influence from interference in the network Handover SucceededHandover Succeeded

Access efficiencyAccess efficiency

Call Drop RatioCall Drop Ratio

Call qualityCall quality

Interference control method Improve the power control precisionImprove the power control precision Improve the receiving efficiency of RakeImprove the receiving efficiency of Rake Reasonable network planningReasonable network planning


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Chapter 4 Multi-service capacity Chapter 4 Multi-service capacity estimationestimation


1 Network capacity 1 Network capacity

restriction factorsrestriction factors

2 Typical capacity design 2 Typical capacity design

methodsmethods

Capacity Restriction FactorsCapacity Restriction Factors Capacity Restriction FactorsCapacity Restriction Factors

The WCDMA network capacity restriction factors in The WCDMA network capacity restriction factors in

the radio network part contain the following:the radio network part contain the following: Uplink interferenceUplink interference Downlink powerDownlink power Downlink channel code resourcesDownlink channel code resources Channel processing unitChannel processing unit Iub interface capacityIub interface capacity

Downlink Transmitting PowerDownlink Transmitting Power Downlink Transmitting PowerDownlink Transmitting Power

N

jCCHT PPP1

The downlink transmitting power comes in two parts: one The downlink transmitting power comes in two parts: one part is used for common channel, and the other part for part is used for common channel, and the other part for dedicated (traffic) channel. dedicated (traffic) channel.

The transmitting power allocated The transmitting power allocated

by the cell to each user varies by the cell to each user varies

with service demodulation with service demodulation

threshold, propagation path loss threshold, propagation path loss

and the interference received by and the interference received by

the userthe user The downlink transmitting power of the cell is shared by all The downlink transmitting power of the cell is shared by all

the users in the cellthe users in the cell We generally use the emulation method to analyze the We generally use the emulation method to analyze the

downlink interference.downlink interference.

Downlink Channel Code ResourcesDownlink Channel Code Resources Downlink Channel Code ResourcesDownlink Channel Code Resources The WCDMA network use the code The WCDMA network use the code

words whose SF is 4~512. The words whose SF is 4~512. The smaller the SF is, the higher the smaller the SF is, the higher the supported data rate will be.supported data rate will be.

In the code tree, the allocable In the code tree, the allocable codes should meet the following codes should meet the following conditions:conditions: No codes on the path from this No codes on the path from this

code to the root node of code tree code to the root node of code tree are allocatedare allocated

No codes in the sub-tree whose No codes in the sub-tree whose root node is this code are allocatedroot node is this code are allocated

Try to reserve the code words Try to reserve the code words whose SF is small, so as to whose SF is small, so as to improve the utilization.improve the utilization.

1

1 -1

1 1

1 1 1 1

1 1 -1 -1

1 -1 1 -1

1 -1 -1 1

C1,0

C2,0

C2,1

C4,0

C4,1

C4,2

C4,3

SF = 1 SF = 2 SF = 4

1

1 -1

1 1

1 1 1 1

1 1 -1 -1

1 -1 1 -1

1 -1 -1 1

C1,0

C2,0

C2,1

C4,0

C4,1

C4,2

C4,3

SF = 1 SF = 2 SF = 4

Downlink Channel Code ResourcesDownlink Channel Code Resources Downlink Channel Code ResourcesDownlink Channel Code Resources Following is an example of code resources allocationFollowing is an example of code resources allocation

SF 4 8 16 32 64 128 256 512 ┏ ━ ●C(256, 0): PCPI CH 2 ┏ 0 ┫ ┃ ┗ ━ ●C(256, 1): PCCPCH 3 ┏ 0 ┫ ┃ ┃ ┏ ━ ●C(256, 2): AI CH 6 ┃ ┗ 1 ┫ ┃ ┗ ━ ●C(256, 3): PI CH 10 ┏ 0 ┫ ┃ ┗ ━ ●C(64, 1): SCCPCH 8 ┏ 0 ┫ ┃ ┃ ┏ ━ ●C(64, 2): SCCPCH 9 ┃ ┗ 1 ┫ ┃ ┗ ━ ○3 ┏ 0 ┫ ┃ ┗ ━ ○1 ┏ 0 ┫ ┃ ┗ ━ ○1 ┃ ┗ ━ ○1

┏ ━ ○2 ┃ ┗ ━ ○3

Channel Processing Unit (CE)Channel Processing Unit (CE) Channel Processing Unit (CE)Channel Processing Unit (CE) The channel processing unit is the quantitative data that The channel processing unit is the quantitative data that

measures the resources logically occupied for service measures the resources logically occupied for service processing. processing.

The resource occupied by the service processing is mainly The resource occupied by the service processing is mainly related to the spreading factor of this service. related to the spreading factor of this service. The smaller the The smaller the SF is, the greater the data traffic will be, and more resources will SF is, the greater the data traffic will be, and more resources will be occupied. be occupied.

The SF of typical services are:The SF of typical services are: AMR12.2kbpsAMR12.2kbps SF=128 SF=128 CS64kbpsCS64kbps SF=32SF=32 PS64kbpsPS64kbps SF=32SF=32 PS144kbpsPS144kbps SF=16 SF=16 PS384kbpsPS384kbps SF=8 SF=8

Channel Processing Unit (CE)Channel Processing Unit (CE) Channel Processing Unit (CE)Channel Processing Unit (CE) If we define the resources required for processing AMR If we define the resources required for processing AMR

12.2kbps services as a channel processing unit, the number 12.2kbps services as a channel processing unit, the number of channel processing units occupied by other services is:of channel processing units occupied by other services is: AMR12.2kbpsAMR12.2kbps 11 CS64kbpsCS64kbps 44 CS144kbpsCS144kbps 88 CS384kbpsCS384kbps 1616 PS64kbpsPS64kbps 44 PS144kbpsPS144kbps 88 PS384kbpsPS384kbps 1616

Iub Interface CapacityIub Interface Capacity Iub Interface CapacityIub Interface Capacity The contents transmitted on the The contents transmitted on the

Iub interface include:Iub interface include: The user data encapsulated in The user data encapsulated in

the AAL2 format (common the AAL2 format (common channel and dedicated channel and dedicated channel)channel)

Signaling data encapsulated Signaling data encapsulated in the AAL5 formatin the AAL5 format

BTS operation & maintenance BTS operation & maintenance datadata

Factors to be considered when estimating the interface capacity:Factors to be considered when estimating the interface capacity: Frame coding efficiency. Through segmentation and encapsulation of Frame coding efficiency. Through segmentation and encapsulation of

the application data at each layer, the data quantity at the bottom the application data at each layer, the data quantity at the bottom layer will be increased to different extents compared with the layer will be increased to different extents compared with the application data at the upper layers. application data at the upper layers.

Traffic. More users will generate more data traffic. Traffic. More users will generate more data traffic. Maintenance efficiency. Certain bandwidth is required in the Maintenance efficiency. Certain bandwidth is required in the

background maintenance for BTS data transmission.background maintenance for BTS data transmission.



1 Network capacity 1 Network capacity

restriction factorsrestriction factors

2 Typical capacity design 2 Typical capacity design

methodsmethods

The comparison of the different The comparison of the different capacity methodcapacity method

Post Erlang-BPost Erlang-B Service 1 (1 unit resource/connection, 12Erl) and service Service 1 (1 unit resource/connection, 12Erl) and service

2 (3 unit resources / connection, 6Erl), requiring 55 unit 2 (3 unit resources / connection, 6Erl), requiring 55 unit resources in totalresources in total

Equivalent ErlangsEquivalent Erlangs Calculated according to benchmark of service 1 (1 unit Calculated according to benchmark of service 1 (1 unit

resource/connection, 12Erl), a total of 39 unit resources resource/connection, 12Erl), a total of 39 unit resources are requiredare required

Calculated according to benchmark of service 2 (3 unit Calculated according to benchmark of service 2 (3 unit resources/connection, 6Erl), a total of 51 unit resources resources/connection, 6Erl), a total of 51 unit resources are requiredare required

Campbell’s TheoremCampbell’s Theorem In the same conditions, 47~49 unit resources are In the same conditions, 47~49 unit resources are

required in total.required in total.

Summary of This ChapterSummary of This Chapter Summary of This ChapterSummary of This Chapter

This chapter deals with the three methods of This chapter deals with the three methods of estimating the multi-service capacity.estimating the multi-service capacity.

The detailedThe detailed process of using the Campbell process of using the Campbell theorem to calculate the capacity is described.theorem to calculate the capacity is described.


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Chapter 5 Network estimation Chapter 5 Network estimation procedureprocedure

Chapter 5 Network estimation Chapter 5 Network estimation procedureprocedure

Mind trace of capacity Mind trace of capacity

planningplanning

Determine the traffic Determine the traffic

modelmodel

Determine the QoSDetermine the QoS

Divide the zones for the region under planning according Divide the zones for the region under planning according to the traffic distribution and clutter features, e.g., dense to the traffic distribution and clutter features, e.g., dense zone, ordinary urban zone, suburbs, rural areaszone, ordinary urban zone, suburbs, rural areas ；；

Perform traffic model analysis on the target zonesPerform traffic model analysis on the target zones Determine the single-carrier planning capacity of each Determine the single-carrier planning capacity of each

target zone according to the traffic model of each specific target zone according to the traffic model of each specific target zone.target zone.

Determine the number of BTSs and carriers for the target Determine the number of BTSs and carriers for the target zones for meeting the capacity requirements.zones for meeting the capacity requirements.

Determine the number of BTSs and carriers according to Determine the number of BTSs and carriers according to the capacity and coverage requirements, and select more the capacity and coverage requirements, and select more BTSs and carriers to ensure meeting both capacity and BTSs and carriers to ensure meeting both capacity and coverage requirements.coverage requirements.

Mind trace of capacity planning

Determine the Traffic ModelDetermine the Traffic Model

Determine the Traffic Model

User distribution data sheetUser distribution data sheet : : （（ user quantityuser quantity /km/km22 ））

Application Application environmentenvironment

2005 2005 2006 2006 2007 2007

Dense urban areaDense urban area 11128 11128 12060 12060 18683 18683 urban areaurban area 462 462 499 499 676 676

SuburbsSuburbs 246 246 266 266 341 341 Rural areasRural areas 15 15 16 16 18 18

Roads/trunk roadsRoads/trunk roads 23 23 35 35 48 48

Determine the Traffic ModelDetermine the Traffic Model

Distribution percentage of users of different grades

Distribution percentage of users of different grades: (subject Distribution percentage of users of different grades: (subject to consideration of each specific period)to consideration of each specific period)

Application Application

environmentenvironment

High-end High-end useruser

Mid-end userMid-end user Low-end userLow-end user

Dense urban Dense urban areaarea

40%40% 40%40% 20%20%

Ordinary Ordinary urban areaurban area

15%15% 25%25% 60%60%

SuburbsSuburbs 5%5% 25%25% 70%70%Rural areasRural areas 1%1% 10%10% 89%89%Road/trunk Road/trunk

roadsroads 1%1% 10%10% 89%89%

Determine the Traffic Model—CS Domain Determine the Traffic Model—CS Domain Traffic ModelTraffic Model

SS TypeSS Type PenetratinPenetratin

g g raterate

BHCBHCAA

AHT AHT (s)(s)

ActiveActivefactorfactor

Mean rateMean rate(kbps)(kbps)

AMRAMRvoicevoice 100 %100 % 11 9090 0.50.5 88

VideophoneVideophone 100 %100 % 0.10.1 5454 11 6464

Determine the Traffic Model—Low-end User PS Determine the Traffic Model—Low-end User PS Traffic ModelTraffic Model

SS TypeSS Type Penetrating Penetrating

raterate BHSABHSA

Packet Packet Call Call Num/Num/SessionSession

PacketPacketNum/Num/PacketPacket

CallCall

PackePacket t

Size Size (bytes(bytes

))

Inter-ArrivalInter-Arrival Time Time

Between Between Packet Packet

Calls Calls (sec)(sec)

EmailEmail 10 %10 % 0.10 0.10 22 3232 480480 320320

WWWWWW 30 %30 % 0.18 0.18 55 2525 480480 412412

Online Online game, game,

ICQICQ 25 %25 % 0.10 0.10 22 33 480480 88

Picture andPicture anddownloadingdownloading

,,

FTPFTP

25 %25 % 0.10 0.10 22 6262 480480 55

Real-time Real-time

videovideo 0 %0 % 0.00 0.00 11 267267 15001500 00

SMSSMS 50 %50 % 0.50 0.50 11 11 160160 00

EMS / MMSEMS / MMS 50 %50 % 0.50 0.50 22 3232 480480 320320

Determine the Traffic Model—Mid-end User Determine the Traffic Model—Mid-end User PS TrafficPS Traffic ModelModel


raterate BHSABHSA


Num/SeNum/Sessionssion


Packet Packet Size Size

(bytes)(bytes)

Inter-Inter-Arrival Arrival Time Time

Between Between Packet Packet Calls Calls (sec)(sec)

EmailEmail 20 %20 % 0.20 0.20 22 3232 480480 320320

WWWWWW 30 %30 % 0.24 0.24 55 2525 480480 412412

Online Online game, game, ICQICQ

15 %15 % 0.20 0.20 22 33 480480 88

Picture andPicture anddownloadingdownloading

,,

FTPFTP

15 %15 % 0.20 0.20 22 6262 480480 55

Real-time Real-time

videovideo 10 %10 % 0.10 0.10 11 267267 15001500 00

SMSSMS 100 %100 % 0.80 0.80 11 11 160160 00

EMS / MMSEMS / MMS 100 %100 % 0.80 0.80 22 3232 480480 320320

Determine the Traffic Model—High-end User Determine the Traffic Model—High-end User PS TrafficPS Traffic ModelModel


raterate BHSABHSA


Num/SeNum/Sessionssion


Packet Packet Size Size

(bytes)(bytes)

Inter-Inter-Arrival Arrival Time Time

Between Between Packet Packet Calls Calls (sec)(sec)

EmailEmail 30 %30 % 0.30 0.30 22 3232 480480 320320

WWWWWW 20 %20 % 0.30 0.30 55 2525 480480 412412

Online game, Online game, ICQICQ

5 %5 % 0.30 0.30 22 33 480480 88

Picture andPicture anddownloading,downloading,

FTPFTP 10 %10 % 0.30 0.30 22 6262 480480 55

Real-time Real-time

videovideo 20 %20 % 0.20 0.20 11 267267 15001500 00

SMSSMS 100 %100 % 0.60 0.60 11 11 160160 00

EMS / MMSEMS / MMS 100 %100 % 0.60 0.60 22 3232 480480 320320

After we obtain the data traffic model of various After we obtain the data traffic model of various users, we can further obtain the general statistics users, we can further obtain the general statistics parameters for facilitating the calculation. parameters for facilitating the calculation.

Mean single-user busy hour throughput (kbit) = low-Mean single-user busy hour throughput (kbit) = low-end user penetrating rate * low-end user Busy Hour end user penetrating rate * low-end user Busy Hour Throughput/user * low-end user percentage + mid-Throughput/user * low-end user percentage + mid-end user penetrating rate * mid-end user Busy Hour end user penetrating rate * mid-end user Busy Hour Throughput / user * mid-end user percentage + high-Throughput / user * mid-end user percentage + high-end user penetrating rate * high-end user Busy Hour end user penetrating rate * high-end user Busy Hour Throughput / user * high-end user percentage Throughput / user * high-end user percentage

Theoretic length of session (bytes) = Packet Call Theoretic length of session (bytes) = Packet Call Num/Session*Packet Num/Packet Call*Packet Size Num/Session*Packet Num/Packet Call*Packet Size (bytes)(bytes)

Mean time of reading (s)=(Packet Call Num/Session-Mean time of reading (s)=(Packet Call Num/Session-1)*Inter-Arrival Time Between Packet Calls (sec)1)*Inter-Arrival Time Between Packet Calls (sec)

Determine the Traffic Model—PS Domain Determine the Traffic Model—PS Domain TrafficTraffic Measurement ParametersMeasurement Parameters

Determining the QoSDetermining the QoS

The capacity under planning is the capacity that meets

certain QoS. Generally, the CS service uses the call

loss/blocking probability as the index GoS. For the PS service,

we use the acceptable delay and acceptable minimum

throughput as the GoS index. Sometimes in the bidding

documents of the operator, the PS service uses the call loss

mode to describe its GoS.


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Transmitting DiversityTransmitting Diversity Transmitting DiversityTransmitting Diversity Transmitting diversity can enhance the Transmitting diversity can enhance the

downlink capacity and coveragedownlink capacity and coverage

Conclusion of capacity enhancement of Conclusion of capacity enhancement of transmitting diversitytransmitting diversity STTD mode: Capacity increase of 17 ~ 24%STTD mode: Capacity increase of 17 ~ 24% TxAA(1) mode: Capacity increase of 16 ~ TxAA(1) mode: Capacity increase of 16 ~

23%23% TxAA(2) mode: Capacity increase of 31 ~ TxAA(2) mode: Capacity increase of 31 ~

37%37%

SectorizingSectorizing SectorizingSectorizing

In the dense urban areas and the normal In the dense urban areas and the normal urban areas with high traffic, increase of urban areas with high traffic, increase of the number of sectors of the BTS is a the number of sectors of the BTS is a method of increasing the capacity. method of increasing the capacity.

6 sectors, generally using the antenna 6 sectors, generally using the antenna whose horizontal lobe is 33ºwhose horizontal lobe is 33º

The capacity of a 6-sector BTS is 1.67 times The capacity of a 6-sector BTS is 1.67 times that of a 3-sector BTSthat of a 3-sector BTS

HSDPAHSDPAHSDPAHSDPA

HSDPA (High Speed Downlink Packet Access) is a downlink HSDPA (High Speed Downlink Packet Access) is a downlink high-speed data service solution of the WCDMA system. The high-speed data service solution of the WCDMA system. The highest rate is up to 12Mbps or more. highest rate is up to 12Mbps or more.

In the subsequent Rel6, the relevant technologies such as In the subsequent Rel6, the relevant technologies such as MIMO and OFDM of the HSDPA will be introduced to further MIMO and OFDM of the HSDPA will be introduced to further increase the downlink capacity. increase the downlink capacity.

Multi-User Detection (MUD)Multi-User Detection (MUD) Multi-User Detection (MUD)Multi-User Detection (MUD)

Single cell:Single cell: Improve the capacity by 70 ~ 100%Improve the capacity by 70 ~ 100%

Multi-cell:Multi-cell: Improve the capacity by 40 ~ 60%Improve the capacity by 40 ~ 60%

Reduce the UE transmitting power:Reduce the UE transmitting power: Reduce the transmitting power by 2 ~ 3 Reduce the transmitting power by 2 ~ 3

dBdB Increase the standby timeIncrease the standby time

SA (Smart Antenna)SA (Smart Antenna) SA (Smart Antenna)SA (Smart Antenna)

The SA can improve the uplink and downlink The SA can improve the uplink and downlink capacity and coverage, and decrease the capacity and coverage, and decrease the transmitting power requirements.transmitting power requirements.

SA gain test resultsSA gain test results

AreaArea UplinkUplink DownlinkDownlink

1x41x4 2x22x2 2x42x4 1x41x4

Capacity gainCapacity gain 1.851.85 1.701.70 3.373.37 3.543.54

Coverage gainCoverage gain 1.421.42 1.351.35 2.022.02 2.072.07

UMTS Multi-Band Layered NetworkUMTS Multi-Band Layered Network UMTS Multi-Band Layered NetworkUMTS Multi-Band Layered Network

With the development of the 3G users and With the development of the 3G users and services, the capacity requirements are higher and services, the capacity requirements are higher and higher, and a single technology can hardly meet higher, and a single technology can hardly meet the growing capacity requirement. the growing capacity requirement.

A mature 3G network can resolve the issue of A mature 3G network can resolve the issue of capacity fundamentally through UMTS multi-band capacity fundamentally through UMTS multi-band layered network.layered network. Supplemental construction: UMTS900, UMTS1800, TD-Supplemental construction: UMTS900, UMTS1800, TD-

SCDMASCDMA

Thank you ！

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Huawei-WCDMA Capacity Planning