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Soc Classification level

1 Nokia Siemens Networks Presentation / Author / Date

WCDMA Network Planning and Dimensioning

WorkshopXx Aug 2008

Leo Chan

Senior Network Performance Specialist


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Agenda

WCDMA Fundamentals WCDMA air interface characteristics WCDMA vs. GSM

Physical Layer Bit Rates

HSPA overview

WCDMA network planning overview Coverage Dimensioning Link budget calculation

Planning margins

Cell range area prediction

Capacity Dimensioning Traffic estimate and model

Air interface dimensioning


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Agenda

WCDMA Fundamentals WCDMA air interface characteristics WCDMA vs. GSM


HSPA overview

WCDMA network planning overview Coverage Dimensioning Link budget calculation

Planning margins





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WCDMA Air Interface Characteristics

5 MHz

3.84 MHz

f

5+5 MHz in FDD mode5 MHz in TDD mode

Frequency

TimeDirect Sequence (DS) CDMA

WCDMA

Carrier

WCDMA

5 MHz, 1 carrier

TDMA (GSM)

5 MHz, 25 carriers

Users share same time and frequency


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Differences between WCDMA & GSM

WCDMA GSMCarrier spacing 5 MHz 200 kHz

Frequency reuse factor 1 118

Power controlfrequency

1500 Hz 2 Hz or lower

Quality control Radio resource

management algorithms

Network planning

(frequency planning)Frequency diversity 5 MHz bandwidth gives

multipath diversity withRake receiver

Frequency hopping

Packet data Load-based packetscheduling

Timeslot basedscheduling with GPRS

Downlink transmitdiversity Supported forimproving downlinkcapacity

Not supported by thestandard, but can beapplied

High bitrates

Services

withDifferentquality

requirements

Efficient

packet data


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Multiple WCDMA carriersLayered network

F1

F2

F2

F3

F3

F3

Micro BTS

Macro BTS

Pico BTSs

1 - 10 km

50 - 100 m200 - 500 m


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Spreadingfactor

Channelsymbol

rate(ksps)

Channel bitrate

(kbps)

DPDCHchannel bitrate range

(kbps)

Maximum userdata rate with -

rate coding(approx.)

512 7.5 15 36 13 kbps

256 15 30 1224 612 kbps

128 30 60 4251 2024 kbps

64 60 120 90 45 kbps

32 120 240 210 105 kbps

16 240 480 432 215 kbps

8 480 960 912 456 kbps

4 960 1920 1872 936 kbps

4, with 3

parallelcodes

2880 5760 5616 2.3 Mbps

Half rate speech

Full rate speech

128 kbps

384 kbps

2 Mbps

Symbolphyb RR 2_SF

WRSymbol

(QPSK modulation)

Physical Layer Bit Rates (DL)


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Physical Layer Bit Rates (DL) - HSDPA

3GPP Release 5 standards introduced enhanced DL bit rates with High Speed

Downlink Packet Access (HSDPA) technology Shared high bit rate channel between usersHigh peak bit rates

Simultaneous usage of up to 15 DL channelisation codes (In HSDPA SF=16)

Higher order modulation scheme (16-QAM) Higher bit rate in same band

16-QAM provides 4 bits per symbol 960 kbit/s / code physical channel peak

rate

Coding rate

QPSK

Coding rate

1/4

2/4

3/4

5 codes 10 codes 15 codes

600 kbps 1.2 Mbps 1.8 Mbps

1.2 Mbps 2.4 Mbps 3.6 Mbps


16QAM

2/4

3/4

4/4




HSDPA


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Physical Layer Bit Rates (UL) - HSUPA

3GPP Release 6 standards introduced enhanced UL bit rates

with High Speed Downlink Packet Access (HSUPA) technology

Fast allocation of available UL capacity for usersHigh peakbit rates

Simultaneous usage of up to 2+2 UL channelisation codes (In

HSUPA SF=24) Initial expected capability 1.46 Mbps

Coding rate

1/2

3/4

4/4

1 x SF4 2 x SF4 2 x SF22 x SF2 +2 x SF4

480 kbps 960 kbps 1.92 Mbps 2.88 Mbps

720 kbps 1.46 Mbps 2.88 Mbps 4.32 Mbps

960 kbps 1.92 Mbps 3.84 Mbps 5.76 Mbps


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HSPA Pushes Functionalities to Base Station

HSDPA = High Speed Downlink Packet Access

HSUPA = High Speed Uplink Packet Access HSPA = HSDPA + HSUPA

HSDPA

HSUPA

Mobile Base station Radio network

controller RNC

HSPA scheduling andretransmission control in

base station

WCDMA schedulingand retransmission

control in RNC

WCDMA R99 uplink/downlink


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HSDPAGeneral Principle

Terminal 1 (UE)

Terminal 2

L1 Feedback = CQI

Data

Data

Link adaptation based onCQI

Packet scheduling based on

CQI

UE's capability

QoS requirements

Power and code resourceavailability

Node B buffer status

HSDPA users may be timeand code multiplexed

L1 Feedback = CQI


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HSDPA Overview

15 Code

Shared

transmission

16QAM

Modulation

TTI = 2 ms Hybrid ARQ

with incr. redundancy

Fast Link

Adaptation

Advanced

Scheduling

Benefit

Higher Downlink Peak rates: 14 MbpsHigher Capacity: +100-200%

Reduced Latency: ~75 ms


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HSUPA Overview

TTI = 10 ms1-4 Code

Multi-Code

transmission

Fast

Power ControlHybrid ARQ

with incr. redundancy

NodeB

Controlled

Scheduling

Benefit

Higher Uplink Peak rates: 2.0 MbpsHigher Capacity: +50-100%

Reduced Latency: ~50-75 ms


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HSxPA Motivation and General Principle

Improved performance and spectral efficiency in DL and UL by introducing a shared channelprinciple:

Significant enchancement with peak rates up to 14.4 Mbps (28 Mbps in Rel7) in DL, and 2Mbps (11.5 Mbps with 16QAM) in UL

Huge capacity increase per site; no site pre-planning necessary

Improved end user experience: reduced delay/latency, high response time

HSDPA (3GPP Rel5)

Fast pipe is shared among UEs

HSUPA (3GPP Rel6)

Dedicated pipe for every UE in UL

Pipe (codes and grants) changing

with time

E-DCH scheduling

Rel. 99

Dedicated pipe for every UE
http://www.computercloset.mtu.edu/wadslocation.htmlhttp://www.computercloset.mtu.edu/wadslocation.html


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UL DCH vs HSDPA vs HSUPA Concepts

HSDPA HSUPA

Modulation QPSK and 16-QAMBPSK and Dual-

BPSK

Soft handover No Yes

HSUPA is like reversed HSDPA, except

Fast powercontrol

No Yes

SchedulingPoint to

multipointMultipointto point

Non-scheduledtransmission

NoYes, for minimum/guaranteed bit rate

Required for near-faravoidance

Efficient UE poweramplifier

Scheduling cannot be asfast as in HSDPA

Similar to R99 DCH but

with HARQHSUPA could be better described as Enhanced DCH inthe uplink than reversed HSDPA

Feature

Variable spreading factor

Fast power control

Adaptive modulation

BTS based scheduling

DCH

Yes

Yes

No

No

HSUPA

Yes

Yes

No

Yes

Fast L1 HARQ No Yes

HSDPA

No

No

Yes

Yes

Yes

Multicode transmission Yes(No in practice)

Yes Yes

HSUPA (E-DCH) is an uplink DCH with BTS-based HARQ and scheduling and true multicode support

Soft handover Yes Yes No(associated DCH only)


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Agenda

WCDMA Fundamentals

WCDMA air interface characteristics WCDMA vs. GSM


HSPA overview

WCDMA network planning overview

Coverage Dimensioning Link budget calculation

Planning margins





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Approaches to 3G Radio Network Planning

There are two fundamental approaches to 3G radio network

planning

Path loss based approach Can be done by 2G planning tools

Results easy to interpret

3G simulation based approach Requires 3G planning tool

Requires detailed input information

Results large range of network performance information


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Path loss based 3G planningResults

The result of path loss based 3G planning is

Coverage maps per service and per area type

Cell dominance areas

Interference levels

Dense Urban

Urban

SuburbanRural

Coverage

Specific service

Dense Urban

Urban

SuburbanRural

Coverage

Specific service


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Simulation based 3G planning

The planned 3G network configuration can be alalysed by

simulation Static (Monte-Carlo) simulationsSupported by most 3G

planning tools (e.g. Netact Planner)

In static simulations users are placed randomly on the planningarea based on traffic distribution information (traffic layer) for

each planned service

The radio link conditions are analysed for each user

Required TX power (UL/DL) based in path loss predictions

and interference level Coverage limitation? Radio interface load (UL/DL) is estimated for each cell

Capacity limitation?


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Simulation based 3G planningResults

Main benefit of 3G simulations is the relatively large quantity of

information which is generated Information is beneficial only if it is interpreted correctly

The main results from a 3G simulation are typically

Service coverage Service probability

Failure probability by failure causes

System capacity

Intercell interference Uplink and downlink transmit powers

Uplink and downlink interference floors


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Simulation based 3G planningVideo callcoverage probability


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Simulation based 3G planningUL load


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Cell load calculation

Cell load calculation is needed in order to estimate the level of air interface

load in the cell

Air interface load depends on service type, radio propagation conditions,network topology and number of active connections

Service type Bitrate, Eb/N0 Propagation conditionsEb/N0, Orthogonality

Network topologyLittle i

Air interface load Power budget

Cell range

Load/cell


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DL Li t t lei

In the real environment we will never have separated cell. Therefore in the load factor

calculation the other cell interferences should be taken into account.This can be introduced by means of the l i t t le i value, which describes how much twocells overlap (bigger overlappingmore inter-cell interferences)

Iother

OWN

OTHER

IIilittle


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0 500 1000 1500140

145

150

155

160

165

170

throughput in kbps

Maximu

mp

ropagationlo

ss(dB)

128 kbps

i = 0.2

i = 0.4

i = 0.6

i = 0.8

Effect of little i

Doubling of the "little i" will cause 70 % throughput decrease of

the original value

DL

UL


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Effect of Speed12.2 kbps speech @ 3, 20, 120 km/h

0 10 20 30 40 50 60 70 80 90 100140

145

150

155

160

165

170

Number of users

M

aximump

ropagationloss(dB)

Macro cell, P(DL) = 43 dBm, P(UL) = 21 dBm3 km/h 12.2 kbps

20 km/h 12.2 kbps

120 km/h 12.2 kbps

UL

DL

For slow moving mobiles alow received Eb/N0value isneeded due to good channelestimate and power control. Onthe other hand high peakpower is needed tocompensate the deepest fades.

For fast moving mobileschannel estimates are worsebut interleaving works moreefficiently. Power control is notable to follow small scalefading (=> power controlheadroomsmaller for highspeed mobiles)

In UL a PC headroomisneeded in calculating thecoverage

In DL the fast power controleffects are included in theaverage required Eb/N0(no

power control headroom in DL)


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Effect of Node B Tx Power10, 20, 30, 40 W, 64 kbps, 3-sector

0 100 200 300 400 500 600 700140

145

150

155

160

165

170

175

Macro cell, P(DL) = 40 to 46 dBm, P(UL) = 21 dBm

DL throughput in kbps

Maximump

ropagationloss(dB)

uplink


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Agenda

WCDMA Fundamentals



HSPA overview



Planning margins





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-Outputtow

ard

Accessplan

ning

Per area and per Phase

Number of Node Bs

Node B Type

Node B Configuration

Node B Upgrade

Configuration

NodeB

Dimensioning

CHC, DRIC, FSM)

Radio Dimensioning data flow

Customer

Requirements

LINK BUDGET

Rel99, CPICH,

HSDPA, HSUPA

RF Planning

Parameters

interf marg

HO gain

environment

etc.

System

Parameters

Eb/No

TX power

etc.

Infrastr.

Parameters

# of sectors

antennas

req cov area

etc.

Capacity

Air Interface

Dimensioning

(Capacity: Rel99

+ HSPA )

Traffic

Demand

per bearer

# of subs

GoS

etc.

System

Parameters

spectral

efficiency

etc.

Outputs

Customer Requirements and Input Parameters


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Introduction

Target of coverage dimensioning is to give estimate of site

coverage area (site count for given area)

Coverage dimensioning requires multiple inputs Service type

Target service probability Initial site configuration

Equipment performance

Propagation environment

Link budget calculations are used for calculation of the sitecoverage area with the given inputs


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Link budget

The target of the link budget calculation is to

estimate the maximum allowed path loss on radiopath from transmit antenna to receive antenna

The minimum Eb/N0(and BER/BLER) requirement isachieved with the maximum allowed path loss andtransmit power both in UL & DL

The maximum path loss can be used to calculatecell range R

Lpmax_DLLpmax_UL

R

Li k b d


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Link budget types

R99 DCH link budget

Uplink Can be based on many different PS and CS services

Downlink Can be based on many different PS and CS services

HSDPA link budget

Uplink HSDPA associated UL DPCH link budget is used which can be 16, 64 ,128 or 384 kbps

Peak HS-DPCCH overhead is included to the R99 DCH Eb/No (this overhead often appears in the transmitter section ofthe link budget)

Downlink Can be based on defined cell edge throughput conditions

HSUPA link budget

Uplink Can be based on defined cell edge throughput conditions

Peak HS-DPCCH overhead is included to the HSUPA Eb/No

Downlink Can be based on defined cell edge throughput conditions

CPICH link budget

Downlink Similar to downlink DCH link budget.

Can be based on CPICH Ec/No at cell edge.

M d l C t t


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Module Contents

Coverage Dimensioning

Link budget calculation R99 link budget

Uplink

Downlink

HSDPA link budget HSUPA link budget

CPICH link budget

Planning margins


R99 UL Li k B d t


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R99 UL Link Budget

The calculation is done for each

service (bit rate) separately Bit rate depends on service, which

can vary in speech service bitrates (e.g. 4.75, 5.9, 7.95, 12.2kbps) to packet service bit rates(e.g. 8, 16, 32, 64, 128 and 384

kbps) as well as video service(e.g. 64 kbps)

Coverage limiting service can bedefined based on customer inputs orlowest path loss based oncalculations

R99 UL Li k B d t


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Soc Classification level38 Nokia Siemens Networks Presentation / Author / Date

R99 UL Link Budget

Transmitter - Handset

Transmission power classes Power Class 4 most common at the

moment (note 2 dB tolerance)

Power Class 3 most common in newmobiles and data cards (+1/-3dBtolerance)

Antenna TX/RX gain Typically assumed to be 02 dBi For data card 2 dBi can be assumed

Body Loss

For CS voice service body loss of 3 dB isassumed as the mobile is near head.

EIRP represents the effective isotropicradiated power from the transmitantenna.

LossBody-GainAntennaTransmitPowerTransmitUEEIRPUplink


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I t f M i


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Interference Margin

Interference margin is calculated from the UL loading () value

From set maximum planned load "sensitivity" is decreased due to the network load (subscribers in the

network) & in UL indicates the loss in link budget due to load.

dBLog 110 10IMargin=

1.25

3

20

10

6

25% 50% 75% 99%

IMargin[dB]

Load factor

R99 UL Li k B d t


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R99 UL Link Budget

ReceiverNode B

Service Eb/No Related to the selected service

Channel model

BLER targets etc,

Service Processing gain

Related to the service bit rate

High processing gains correspond toservices with low bit rates. Theseservices tend to have more relaxed linkbudgets and generate smallerincrements in cell loading.

Receiver thermal sensitivityThisrepresents the receiver sensitivitywhen the system is loaded i.e. aninterference margin has been included

GainProcessingEb/NoRequirede_floornterferencySensitivitReceiver I

RateBit

RateChipLOG10GainProcessingService

R i d E /N


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Required Eb/N0

When Eb/N0is selected, it has to be known in which conditions it is defined (selectclosest Eb/N0value to the prevailing conditions if available) Service and bearer

Bit rate, BER requirement, channel coding

Radio channel Doppler spread (Mobile speed, frequency)

Multipath, delay spread

Three main groups of channels models that are widely usedto model different propagation environments. 3GPP models, Case 1-5

COST 259 models, Typical urban (TU), Rural area (RA), Hilly terrain (HT)

ITU models, Indoor A/B, Pedestrian A/B, Vehicular A/B

Receiver/connection configuration Handover situation

Fast power control status

Diversity configuration (antenna diversity, 2-port, 4-port)

Some corrections have to be done in the link budget in case the conditions do not

correspond the used Eb/N0 Soft handover gain

Power control gain

Fast fading margin

R99 UL Link Budget


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R99 UL Link Budget

ReceiverNode B

RX antenna gain Is different for different frequencies

Gain and size varies

Cable loss

In Flexi the remote RF head

(feederless solution) minimizesthe influence of cable losses

MHA can be used to compensatethe cable loss as well as lower thesystem noise figure (not in Flexi)

R99 UL Link Budget


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R99 UL Link Budget

ReceiverNode B

UL fast fade margin

SHO gain (old MDC gain)

Gain against shadowing

Fast fading margin


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Fast fading margin

0 0.5 1 1.5 2 2.5 3 3.5 410

15

20

25

dB

0 0.5 1 1.5 2 2.5 3 3.5 4-10

0

10

20

dBm

0 0.5 1 1.5 2 2.5 3 3.5 4-0.5

0

0.5

1

1.5

0 0.5 1 1.5 2 2.5 3 3.5 45

10

15

dB

Seconds

Mobile transmissionpower starts hittingits maximum value

Eb/N0target

increases fast

Received qualitydegrades, more

frame errors

MS moving towards the cell edge

Some headroom is needed in the mobile station TX power for

maintaining adequate fast power control This is needed at cell edge for UEs to be able to compensate fast fading

Typical values are from 2 to 5 dB for slow-moving mobiles (according toWCDMA for UMTS)

Soft Handover (MDC) Gain UL


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Soft Handover (MDC) GainUL

SHO gain (Macro Diversity Combining) gives the Eb/N0 improvement in

soft handover situation compared to single link connection At cell edge the SHO gain can be around 1.5 dB,

Simulation results in following figure shows that the gain depends on UE speedas well as from two branches path loss differences

An average over the cell in UL is commonly 0 dB, this is due to the fact

that Significant amount of diversity already exist 2-port UL antenna diversity, multipath diversity (Rake)

The graph includes both Softer and Soft Handover (however it is not possible tosee those gains separately)

Soft Handover combining is done at RNC level by using just selection combining

(based on frame selection) Softer Handover combining is done at the BTS by using maximal ratio combining

In case of more than 2 connections - no more gain (compared to case of twobranches)

Soft Handover (MDC) Gain UL


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Soft Handover (MDC) GainUL

Tx power, uplink

-0.5

0

0.5

1

1.5

2

0 5 10

Difference between the SHO links (dB)

SHOM

D

C

gain(dB)

MS speed 3km/h

MS speed 20km/h

MS speed 50km/h

MS speed 120km/h

Soft HOCombining(including softer combininggain for the other branch)Softer HO

Combining

Dynamic SimulatorResult for 2 branches

Gain Against Shadowing (slow fading)


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At cell edge there is the gain against shadowing. This is

roughly the gain of a handover algorithm, in which the bestBTS can always be chosen (based on minimal transmissionpower of MS) against a hard handover algorithm based ongeometrical distance.

In reality the SHO gain is a function of required coverage probability

and the standard deviation of the signal for the environment.

The gain is also dependent on whether the user is outdoors, where thelikelihood of multiple servers is high, or indoors where the radio channeltends to be dominated by a much smaller number of serving cells.

For indoors users the recommendation is to use smaller SHO gain value

Soft handover gain can be understood also as reduction of Slow FadingMargin (See Cell range estimation)



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Typical average value of the Gain against shadowing is between 2and 3 dB


R99 UL Link Budget


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R99 UL Link Budget

Building penetration loss This parameter is clutter specific,

normally for dense urban areas thisvalue is higher than in rural area.Recommended values for urban is 16 dBand suburban 12 dB.

Indoor location probability This parameter defines the probability of

connection in indoors, value depending

on clutter and area, varies from 8595%

Indoor standard deviation Correspondingly clutter and area

dependent, varies from 5 to 12 dB.

Shadowing margin

This is calculated from indoor locationprobability and standard deviation.Typical values for slow fading marginsfor 90-95% coverage probability are:

outdoor: 68 dB (lower for suburban/rural)

indoor: 1015 dB (lower forsuburban/rural)

These planning margins are defined in detail later on!

R99 UL Link Budget


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R99 UL Link Budget

marginfadeslowBPLgainULSHO-marginfadefastULgainMHA-losscableainRxAntennaGysensitivitReceiverrequiredpowerotropicI

s

Isotropic power required

Required signal power is calculatedto take into account the buildingpenetration loss and indoorstandard deviation as well asreceiver sensitivity and additional

margins.

Allowed propagation loss

requiredpowerIsotropic-EIRP. losspAllowedpro

Module Contents


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Module Contents



Uplink

Downlink

HSDPA link budget

HSUPA link budget

CPICH link budget

Planning margins


R99 DL Link Budget


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R99 DL Link Budget

The calculation is done for each

service (bit rate) separately Bit rate depends on service, which

can vary in speech service bit rates(e.g. 4.75, 5.9, 7.95, 12.2 kbps) topacket service bit rates (e.g. 8, 16,32, 64, 128 and 384 kbps) as wellas video service (e.g. 64 kbps)

Coverage limiting service can bedefined based on customer inputs orlowest path loss based oncalculations

R99 DL Link Budget


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R99 DL Link Budget

GainAntennaTransmitonlossMHAinserti-lossCabler)TxPowerUseower,MIN(MaxTxPEIRPDownlink

TransmitterNode B

Max Tx Power (total) Max Tx power is based on selected WPA, e.g. 20 W =

43 dBm and 40 W = 46 dBm. This depends on Node Btype and configuration.

This parameter is used in definition of Max Tx powerper radio link.

Max Tx power per radio link Max Tx power per radio link is upper limit for DL power

calculation.

TX power per user Tx power per user is depended on DL load used in link

budget calculation (it is used to define how muchpower is used per user)

This parameter notifies the average user location suchas 6 dB which correspond to average user location.

MHA insertion loss In DL the insertion loss needs to be noticed.

Commonly 0.5 assumed.

Other margins Cable loss, Tx antenna gain noticed as earlier.

EIRP EIRP is calculated as follows

DL Power calculation


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DL Power calculation

The DL power calculation is depended on two different methods Max DL RL power

This is as upper limit which is limitation based on system parameters

DL Tx power per user average distribution and power calculation related to the DL load.

In case of low load then Max DL power is limiting

In case of high DL load then the DL tx power per user is limiting

The selection of peak to average power ratio depends on many factors

The lower DL power is selected from Max Tx power per connection and TX powerper user EIRP is calculated as follows:

As an example:

Service Type Speech CS Data PS Data

Downlink bit rate 12.2 64 64 128 384 kbps

Max tx power per connection 34.2 37.2 37.2 40.0 40.0 dBm

Tx power per user (IPL 6 dB) 60% load 34.6 38.6 37.6 40.3 42.0 dBm

EIRP (0.5 cable loss, 18.5 tx antenna gain) 52.2 55.2 55.2 58.0 58.0 dBm

GainAntennaTransmitonlossMHAinserti-lossCabler)TxPowerUseower,MIN(MaxTxPEIRPDownlink

R99 DL Link Budget


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R99 DL Link Budget

marginceinterferenfigurenoiseHandsetnoisehermal_I Tfloorenterferenc

Receiver - Handset

Handset Noise Figure Handset NF varies between

frequency and can vary betweendifferent models

Interference margin

Interference margin is definedbased on downlink load andinterference

Thermal noise

As defined in Uplink

Interference floor

Handset Noise Figure


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Handset Noise Figure

Handset noise figure varies between frequencies as well as

between models 3GPP Specification defines certain limits for UE performance

for different frequencies

For higher frequencies (e.g. 2 GHz) specification defines 9 dBrequirement for UE

For lower frequencies (e.g. 900 MHz) 11 dB requirement is specified

R99 DL Link Budget


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R99 DL Link Budget

Service Eb/No

Related to the selected service inDL

Channel model

BLER targets etc,

Refer to Uplink part

Service Processing gain Related to the service bit rate

Receiver Sensitivity

As defined in UL

GainProcessingEb/NoRequirede_floornterferencySensitivitReceiver I

R99 DL Link Budget


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R99 DL Link Budget

RX antenna gain Commonly in data cards some antenna gain is

defined, commonly this is just 2 dBi.Assumption needs to be as defined in UL

Body loss Similarly as in uplink the DL needs to consider

the body loss if defined e.g. for voice service inUL

DL Fast fading margin No fast fading margin noticed in DL as was

noted in UL. In DL fast fading margin is notusually applied due to lower power controldynamic range.

SHO gain In SHO gain 1 dB advantage can be noticed

compared to the UL.

Gain against shadowing This is harmonized between UL/DL as the

selection of better cell can happen in eitherdirection independently.

Soft Handover (MDC) Gain DL


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Soft Handover (MDC) Gain DL

In edge of the cell a 34 dB SHO gain can be seen on required DL Eb/N0

in SHO situations compared to single link reception Combination of 23 signals

Commonly in dimensioning the DL SHO gain is assumed to be 2.5 dB

In DL there is also some combining gain (about 1.2 dB) as an averageover the cell this is due to UE maximal ratio combining

soft and softer handovers included from MS point there is no difference between soft and softer handover

average is calculated over all the connections taking into account the averagedifference of the received signal branches (and UE speed)

40% of the connections in soft handover or in softer handover and 60% no softhandover

taking into account the effect multiple transmitters combination of dynamic simulator results and static planning tool

in case more than 2 connections - no more gain (compared to case of twobranches)


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Module Contents


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Module Contents



HSDPA link budget

Uplink

Downlink

HSUPA link budget

CPICH link budget

Planning margins


Uplink DPCH link budget for HSDPA


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Up C budget o S

Overall same approach as normal R99uplink link budget except the

requirement to include a peak overheadfor the HS-DPCCH

HS-DPCCH Overhead is dependentupon the selected associated DCH(16/64/128/384).

Use the values with soft handover as atthe cell edge connection is commonly in

SHO Without SHO can be used in some special

case like I-HSPA without Iur interfaces

Rest of the link budget is the same asfor a conventional Uplink link budget

The soft handover gain effect on the cellradius and site coverage

Module Contents


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HSDPA link budget

Uplink

Downlink

HSUPA link budget

CPICH link budget

Planning margins


HS-PDSCH link budget


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g

In HSDPA link budget, one of two approaches can be adopted

Target uplink bit rate can be specified and link budget completed from top to bottom todetermine the maximum allowed path loss

HS-PDSCH SINR should correspond to the targeted cell edge throughput

Existing maximum allowed path loss can be specified and link budget completed frombottom to top to determine the achievable uplink bit rate at cell edge

The total transmit power assigned to the HS-PDSCH and HS-SCCH depends onRNC parameters and CCCH power and in shared carrier also on DCH traffic load

HS-PDSCH does not enter soft handover, which leads to SHO gain of 0 dB

An overhead for HS-DPCCH channel has to be taken into account in UL whenHSDPA is active

HS-PDSCH link budget


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g

Max Tx poweris the allocated power for HS-PDSCH which depends on the CCCH and inshared carrier also on the required DCH power

41 dBm in 20 W dedicated HSDPA carrier

SINR Requirementdepends on the requiredcell edge throughput

Spreading gainis calculated from the usedspreading factor 16

Soft handover gainis 0 dB because no SHOon HS-PDSCH

Cel l edge throu ghputaffects the requiredSINR


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HSDPA signal quality SINR


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GeometryFactor

TotalTransmitPower

SpreadingFactor

Orthogonalityfactor

Transmitted

HS-PDSCHpower

G

P

PSFSINR

tot

PDSCHHS

11

16

g q y

HSDPA signal quality (SINR) depends on

Available power for HSDPA Channel conditions

Cell range (pathloss)

Interference level over cell area

HSDPA features and configuration

SINR and HSDPA Throughput


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g p

The single-userHSDPAthroughput versus its averageHS-DSCH SINR is plotted.

Notice that these resultsinclude the effect of fast fadingand dynamic HS-DSCH linkadaptation (and HARQ).

An average HS-DSCH SINRof 23 dB is required to achievethe maximum data rate of 3.6Mbps with 5 HS-PDSCHcodes

Benefit from using highercodes (10/15) is onlyexperienced for higher SINRvalues >10 dB

Ave

ragesingle-userthroughput[Mbps]

Average SINR (1 HS-PDSCH) [dB]

0.5

1.0

1.5

2.0

2.5

-10 -5 50 10 15 20 25 300

3.0

3.5

4.0

HS-DSCH POWER 7W (OF 15W), 5 CODES,

1RX-1TX, 6MS/1DB LA DELAY/ERROR

Rake, Ped-A, 3km/h

Rake, Veh-A, 3km/h

Rake, Ped-B, 3km/h

MMSE, Ped-A, 3km/h

MMSE, Ped-B, 3km/h

Rake, Veh-A, 30km/h

Average HS-DSCH SINR [dB]

Common cell

edge condition

Insid

e

macr

o

cell

Micro cell,

LOS, low

interferenc

e

Release 5 HSDPA Downlink HS-PDSCH link


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Cell radius calculation

The cell radius can be calculated with different cell edge throughputs

Also the PtxMaxHSDPA can vary based on Node B power (e.g. 20W or 40W)

Next Figure shows site coverage area (sqkm) with different throughputs andwith different HSDPA powers (5, 10 and 15 W)

budget

HS-SCCH link budget


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g

HS-SCCH makes use of power control basedupon HS-DPCCH CQI and ACK/NACK

Usual to assume 500 mW of transmit poweralthough a greater power can be assigned forUE at cell edge

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

040

80

120

160

200

240

280

320

360

400

440

480

520

560

600

640

680

720

760

800

HS-SCCH Transmit Power (mW)

Occurances

HSDPA Tx Power = 30 dBm



HS-SCCH does not enter soft handover

HSDPA throughputOrthogonality


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Close to the BTS the own

cell interference dominatesand SINR depends only onHSDPA power share of totalcell power and orthogonality

Even in these optimalconditions high throughputrequires high orthogonality

Orthogonality of higher than 0.9can be achieved in isolatedenvironment

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 1000 2000 3000 4000 5000 6000 7000 8000 9000

Throughput, kbps

Ortho

gonality

10% BTS pow er for HSDPA 50% BTS pow er for HSDPA

80% BTS power for HSDPA

116 totPDSCHHS

P

PSFSINR

Example: HSDPA vs. UL return channel link


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budget

UE is able to decrease the UL bit rate in case of UL power limitation

Return link link budget with 16 kbit/s bit rate Cell edge throughput is highly dependent on the HSDPA power

4W75 kbit/s, 8 W 200 kbit/s, 12 W 330 kbit/s, 16 W 430 kbit/s

130.00

135.00

140.00

145.00

150.00

155.00

160.00

165.00

50 100 150 200 250 300 350 400 450 500

HSDPA throughput

Ma

ximumpathloss

PS 16 UL, HSDPA

PS 64 UL, HSDPA

PS 128 UL, HSDPA

PS 384 UL, HSDPA

HSDPA, 4 W

HSDPA, 8 W

HSDPA, 12 W

HSDPA, 16 W

Module Contents


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HSDPA link budget

HSUPA link budget

CPICH link budget Planning margins


HSUPA Uplink Link Budget (I)


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Similar to an HSDPA link budget, one of two

approaches can be adopted target uplink bit rate can be specified and link

budget completed from top to bottom todetermine the maximum allowed path loss

existing maximum allowed path loss can bespecified and link budget completed from bottom

to top to determine the achievable uplink bit rateat cell edge

Majority of uplink link budget is similar to thatof a R99 DCH

HSUPA uplink link budget makes use of Eb/No

figures rather than SINR figures

Eb/N l k t bl

HSUPA Uplink Link Budget (II)


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Eb/No look-up tables

Cell Edge ThroughputTarget BLER

Propagation Channel

used to index the Eb/Nolook-up table anddetermine an appropriate

Eb/No figure as well ascalculate processing gain

Eb/No values are included for

Bit rates 32 kbps to 1920 kbps

Target BLER 1, 5 and 10 %

Propagation channels Vehicular A 30 km/hr and Pedestrian A 3km/hr

Eb/No values include E-DPDCH, E-DPCCH and DPCCH

HSUPA Uplink Link Budget (III)


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Transmit section of link budget is identical to that of aHSDPA associated R99 DPCH link budget.

Transmit antenna gain and body loss can be configured foreither a data card or mobile terminal. Thus the gain can be 2

dBi

HS-DPCCH overhead is slightly different as in DPCH. Nexttable shows the overhead values for SHO and non-SHOcase:

Interference floor = Thermal noise + Noise Figure +Interference Margin - Own Connection Interference

Interference Margin = -10*LOG(1- Uplink Load/100)

The own connection interference factor reduces the uplinkinterference floor by the UEs own contribution to the uplink

interference, i.e. by the desired uplink signal power

This factor is usually ignored in R99 DCH link budgetsbecause the contribution from each UE is relatively small

This factor is included in the HSUPA link budget becauseuplink bit rates can be greater and the uplink interferencecontribution from each UE can be more significant

HSUPA Uplink Link Budget (IV)


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The receiver sensitivity calculation is the same as that fora R99 DCH link budget

Receiver Sensitivity = Interferencefloor + Eb/No - ProcessingGain

Receiver RF parameters, gains and margins are thesame as for a R99 DCH link budget

same fast fade margin due to same inner looppower control

No differences in calculations

Module Contents


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HSDPA link budget

HSUPA link budget



CPICH link budget


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CPICH reception is required forcell access and synchronisation

The CPICH link budget is similarto the downlink service linkbudget

The CPICH transmit power isdefined by RNC parameter

The CPICH link budget is

calculated based on C/Irequirement(Ec/Io) of -15 dB

CPICH reception does not benefitfrom soft handover

Channel CPICH

Service Pilot

Transmitter - Node B

Pilot Tx Power 33.00 dBm

Cable Loss 0.5 dBi

MHA Insertion Loss 0.0 dBTx Antenna Gain 18 dB

EIRP 50.5 dBm

Receiver - Handset

Handset Noise Figure 7 dB

Thermal Noise -108 dBm

Downlink Load 80 dB

Interference Margin 6.99 dB

Interference Floor -94.0 dBm

Required Ec/Io -15.0 dB

Receiver Sensitivity -109.0 dBm

Rx Antenna Gain 0 dB

Body Loss 3 dB

DL Fast Fade Margin 0 dB

SHO gain 0 dB

Gain against shadowing 2.5 dB

Building Penetration Loss 12 dB

Indoor Location Prob. 90 %

Indoor Standard Dev. 10 dB

Shadowing Margin 7.8 dB

Isotropic Power Required -88.7 dB

Allowed Prop. Loss 139.2 dB

Example: CPICH vs. HSDPA coverage


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The pilot coverage can be extended with higher power

Less power for HSDPA and higher cell range decrease thecell edge throughput

2W pilot142 dB and 550 kbit/s

3W pilot145 dB and 440 kbit/s

4W pilot

147 dB and 350 kbit/s

130

135

140

145

150

155

160

165

50 100 150 200 250 300 350 400 450 500

HSDPA throughput

Maximum

pathloss 2W CPICH

3W CPICH

4W CPICH

HSDPA, 2W CPICH

HSDPA, 3W CPICH

HSDPA, 4W CPICH

Module Contents


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HSDPA link budget

HSUPA link budget



Planning margins


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Output of the link budget calculation is a maximum path loss

estimate from transmit antenna to the received antenna In coverage planning additional planning margins are

introduced to take into account

Signal shadowing due to obstructions (buildings, trees etc.) on the radiopathSlow fading

Signal attenuation by building structures for indoor users

Attenuation to the signal caused by phone userBody loss

If not taken into account in link budget

Slow fading margin


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Slow fading is caused by signalshadowing due to obstructions onthe radio path

A cell with a range predicted frommaximum pathloss will have aCoverage Probability of about 75%

Lot of coverage holes due toshadowing

Slow fading margin (SFM) isrequired in order to achieve highercoverage quality, CoverageProbability

Smaller cell, less coverage holesover cell area

Cell range from prediction model

Max pathloss

from link budget

Pathlossprediction model

Cell Range

Coverage

probability = 75

% outdoors

Max pathloss

from link budget

Pathlossprediction model

Cell Range

Coverage

probability > 75

% outdoor

- Slow fading

margin

........max RSFMLRf

Slow fading margin


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Slow Fading Margin

SFM [dB] (xo-Po)

Point Location

Probability,

Pxo

a bArea Location

Probability, Fu

-5.00 26.60% -0.4419 1.2964 56.00%

-4.50 28.69% -0.3977 1.2964 58.00%

-4.00 30.85% -0.3536 1.2964 59.99%-3.50 33.09% -0.3094 1.2964 61.97%

-3.00 35.38% -0.2652 1.2964 63.93%

-2.50 37.73% -0.2210 1.2964 65.86%

-2.00 40.13% -0.1768 1.2964 67.76%

-1.50 42.56% -0.1326 1.2964 69.63%

-1.00 45.03% -0.0884 1.2964 71.45%

-0.50 47.51% -0.0442 1.2964 73.23%

0.00 50.00% 0.0000 1.2964 74.96%

0.50 52.49% 0.0442 1.2964 76.63%

1.00 54.97% 0.0884 1.2964 78.25%1.50 57.44% 0.1326 1.2964 79.81%

2.00 59.87% 0.1768 1.2964 81.30%

2.50 62.27% 0.2210 1.2964 82.73%

3.00 64.62% 0.2652 1.2964 84.09%

3.50 66.91% 0.3094 1.2964 85.38%

4.00 69.15% 0.3536 1.2964 86.61%

4.50 71.31% 0.3977 1.2964 87.76%

5.00 73.40% 0.4419 1.2964 88.85%

5.50 75.41% 0.4861 1.2964 89.87%

6.00 77.34% 0.5303 1.2964 90.82%

6.50 79.17% 0.5745 1.2964 91.71%

7.00 80.92% 0.6187 1.2964 92.53%

7.50 82.57% 0.6629 1.2964 93.29%

8.00 84.13% 0.7071 1.2964 93.99%

8.50 85.60% 0.7513 1.2964 94.64%

8.80 86.43% 0.7777 1.2964 95.00%

9.50 88.25% 0.8397 1.2964 95.77%

10.00 89.44% 0.8839 1.2964 96.25%

Slow fading margin values

presented for the differentPoint Location andArea

Location Probability values

Standard Deviation, s= 8dB

SFM = 0

Point Location Probability = 50 %

Area Location Probability = 75 %

Building penetration loss


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Pref= 0 dB

Pindoor= -3 ...-15 dB

Pindoor= -7 ...-18 dB

-15 ...-25 dB no coverage

rear side :

-18 ...-30 dB

signal level increases with

floor number :~1,5 dB/floor(for 1st ..10th floor)

Signal levels from outdoor base stations into buildings are estimated byapplying a Building Penetration Loss (BPL) margin

Slow fading standard deviation is higher inside buildings due to shadowingby building structures

There are big differences between rooms with window and deep indoor (10..15 dB)

Area Location ProbabilityIndoors


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........ RBPLSFMLRf

222

21

...

...

1 Nindoorindooroutdoor

NmmmBPL

Add mean values,

superimpose standard deviations

BPL: Building Penetration Loss [dB]

For indoor location area probability calculation, mean penetration losses

have to be added, and increased standard deviation needs to be takeninto account as well:

Module Contents


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HSDPA link budget

HSUPA link budget



Propagation Models used in common planningtools


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toolsOkumura-Hata

The most commonly used statistical model

Walfish-Ikegami

Statistical model especially for urban environments

Juul-Nyholm

Same kind of a prediction tool as Hata, but with

different equation for predictions beyond radio horizon (~20km)

Ray-tracing

Deterministic prediction tool for

microcellular environments

Statis

ticaltobe

tun

ed!

Deterministic


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Propagation ModelsOkumura-Hata & COST Hatamodel


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model

ectionMorphoCorrFactorCorrection+log(R))](hlog6.55-[44.9)a(h-)(hlog13.82-(f)logB+A=L BS10MSBS1010

.............R

8.0)(log1.56-h0,7]-(f)log[1,1=)a(h

MHz2000


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Cell range calculationsExample


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Differences on planning margin are reflected to cell size

Indoor

Speech 1.1 km Uplink limited

Video call 1.1 km Uplink limited

PS Data 384/384 0.7 km Uplink limited

PS Data 384/HSDPA 384 0.8 km Downlink limited

HSUPA 384/HSDPA 384 0.8 km Downlink limited

HSUPA/HSDPA 1 Mbps 0.6 km Downlink limited

Indoor

Speech 2.0 km Uplink limited

Video call 2.0 km Uplink limitedPS Data 384/384 1.2 km Uplink limited

PS Data 384/HSDPA 384 1.4 km Downlink limited

HSUPA 384/HSDPA 384 1.5 km Downlink limited

HSUPA/HSDPA 1 Mbps 1.3 km Downlink limited

2100 MHz

G_ant = 18.5 dBi

900 MHz

G_ant = 16 dBi

Effect of planning margin on coverage area


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Planning margin parameter settings have a major effect on

the cell area calculations

NRT 64/384 planning margin effect on Coverage Area

(stepped +/- 1dB)

-80%

-60%

-40%

-20%

0%

20%

40%

60%

80%

100%

120%

-6 -4 -2 0 2 4 6

Change of parameter

EffectinCoverageArea

Building penetration loss change (ref = 16dB)

Indoor standard deviation change (ref = 12dB)

Agenda


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WCDMA Fundamentals



HSPA overview



Planning margins


Capacity Dimensioning Traffic estimate and model Air interface dimensioning

Module Contents


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Traffic estimate and model

Air interface dimensioning DCH load calculation

HSDPA capacity

HSUPA capacity

Basic Traffic Model

Air InterfaceDimensioning

Channel CardDimensioning

RNCDimensioning

IubDimensioning

IuDimensioning

IurDimensioning

+

Topology Subscribers

Radionetw

ork

Accessnetwork

Module Contents


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Traffic estimate and

model


HSDPA capacity HSUPA capacity

Basic Traffic Model



RNCDimensioning

IubDimensioning

IuDimensioning

IurDimensioning

+


Radionetw

ork

Accessnetwork

Traffic estimation


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The traffic estimation requires information related to the

network topology, subscribers and traffic Cell area from Capacity dimensioning

Subscriber density from marketing

Subscriber traffic profile from marketing

Basic Traffic Model



+


Subs densityCell area Traffic / subscriber

Traffic / cell

Traffic / site

Subscriber density


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Operator subscriber density depends on

Population density Mobile phone penetration

Operator market share

The subscriber density can be considered quite stable inmature markets Mobile phone penetration close to 100% for basic services

Major changes possible only when new operators come to the marketor with aggressive marketing campaigns

In developing markets fast changes in mobile phonepenetration and operator market share

Traffic information


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The subscriber density and user traffic profile are the main requirementsfor capacity dimensioning

Traffic forecast should be done by analysing the offered Busy Hour trafficper subscriber for different services in each rollout phase

Traffic data:

Voice : Erlang per subscriber during busy hour of the network

Codec bit rate, Voice activity

Video call : Erlang per subscriber during busy hour of the network

Service bit rates

NRT data : Average throughput (kbps) subscriber during busy hour of the network

Target bit rates

User traffic profile - Marketing Forecast


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(Average) traffic demand per subscriber in busy hour: 2008/2009 Speech telephony: 2023 mErl

Video telephony: 2,53.0 mErl

SMS 0.3

Data services ~ 500900 bps Source: Mobile Networks:Subscription Tool - Market Compendium Summer 2006 [Subscriber

Number & Speech traffic]

Marketing data predict Minutes of use per subscriber per month (MoU)

Mapping of MoU values to traffic demand per subscriber in busy hour High customer segment: 0.68% of monthly traffic in busy hour

- Considering 22 days and 15% daily traffic in BH

Medium customer segment: 0.5 % of monthly traffic in busy hour - Considering 30 days and 15% daily traffic in BH

Low customer segment: 0.33% of monthly traffic in busy hour

- Considering 30 days and 10% daily traffic in BH

User traffic profile - Speech traffic evolution


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3600

100060__/____][_

Days

ratioionconcentratBHMonthSubscriberperuseofMinutesmErlDemandTraffic

Speech traffic evolution

0,00

5,00

10,00

15,00

20,0025,00

30,00

35,00

40,00

2006 2007 2008 2009 2010 2011

year

mErl High traffic customer

Medium traffic customer

Low traffic customer

User traffic profile - Video Call traffic evolution


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2

2,5

3

3,5

4

2006 2007 2008 2009 2010 2011

[mErl]

User traffic profile - Data traffic evolution


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0

250

500

750

1000

1250

1500

1750

2000

2250

2500

2750

3000

2006 2007 2008 2009 2010 2011

[bps/subscriberin

BH]

High Medium Low

PS data traffic demand

[bps] per subscriber in

busy hour: 20062011

Highmediumlow(includes various PS data

applications)

Example: Traffic estimation


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Cell area: 10 km2

Planning area: 100 km2 and 10 000 subscribers 100 subs/km21000 subs/cell

User profile Speech traffic: 25 mErl/subs/BH

NRT data traffic: DL 750 bps/subs/BH, UL 75 bps/subs/BH

Cell traffic: Speech - 25 Erl/cell/BH, NRT data DL - 750

kbps/cell/BH, NRT data UL - 75 kbps/cell/BH

Traffic model


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Traffic model is used to derive the required capacity from

average traffic and service quality requirement

Real time traffic (speech, video call, video streaming) iscommonly modelled with Erlang-B model

Average traffic (Erlangs) Blocking probability (%)

Required number of traffic channels

Non-real time traffic (web, email services) can be modelled asaverage traffic with defined overhead

Packet data modelling


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Packet data traffic is a sum of multiple services with different

traffic profiles and service quality requirements Accurate modelling of packet data traffic requires multiple assumptionsand complex simulations

Practical packet data traffic model utilises average bit ratewith fixed overhead for protocol and QoS

The overhead can assumed to be 27%

This figure includes the L2 re-transmission overhead of 10% and 15%of buffer headroom to avoid overflow (peak to average load ratioheadroom) => (1+0.10) x (1+0.15) = 1.265 => 26.5% overhead

Required bit rate = (1 + Overhead) * Average bit rate

Example: Traffic models


109/132



Cell traffic: 25 Erl/cell/BH, 750 kbps/cell/BH

Speech: 25 Erl & 2% blocking 34 traffic channels

NRT data DL: 750 kbps * (1 + 26%) = 945 kbps

NRT data UL: 75 kbps * (1 + 26%) = 94.5 kbps

Module Contents


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Basic Traffic Model



RNCDimensioning

IubDimensioning

Iu

Dimensioning

IurDimensioning

+

Topology Subscribers Traffic estimate and model


HSDPA capacity

HSUPA capacity

Radionetw

ork

Acc

essnetwork

Load CalculationIntroduction


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Cell load calculation is needed in order to estimate the levelof air interface load in the cell

Air interface load depends on service mix, radio propagationconditions, network topology and number of activeconnections as well as traffic inputs or load estimation

Service typeBitrate, Eb/N0 Propagation conditionsEb/N0, Orthogonality

Network topologyLittle i

Air interface load Link budget

Cell range

Load/cellLoad estimation

Traffic inputs


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Uplink load equation for DCH


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iaRW

NoE

j

jbNj

j

jUL *1/

/

1

Simplified uplink load equation can be used to evaluate the uplink DCH capacity

Uplink load

Activity factor

Chip rate Bit rate

EbNo requirement

Rise in intercellinterference ratio

Intercellinterference ratio

Activity factor for speech must account for

DPCCH. 67% for uplink based upon 50 %speech activity

Rise in intercell interference ratio (power rise)dependant upon average UE speed

Intercell interference ratio (little i) dependsupon the network layout and environment

0

2

4

6

8

10

12

14

16

18

10

20

30

40

50

60

70

80

90

95

98

loading/%

loss/dB

UL Little i


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In the real environment we will never have separated cell.

Therefore in the load factor calculation the other cellinterferences should be taken into account.

This can be introduced by means of the Little ivalue, whichdescribes how much two cells overlap (bigger overlapping more inter-cell interferences)

Iother

OWN

OTHER

I

Ii

Downlink load equation for DCH


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Downlink Load Equation

Downlink load equation can be used to evaluate the downlink DCH capacitywhen combined with a link budget

Downlink loadActivity factor

Chip rate Bit rate

EbNo requirement

Orthogonality

Intercellinterferenceratio

Activity factor for speech must account for DPCCH. 63% for downlink based

upon 50 % speech activity Orthogonality dependant upon the propagation channel conditions

Intercell interference ratio (little i) depends upon the network layout andpropagation environment

iRW

NoEOHSHO

j

jbNj

j

jDL

1

/

/)_1(

1

Soft handoveroverhead

Other cell to own cell interference and SHOoverhead


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The level of interference received from neighbouring cell

depends strongly on Network layout (site locations, antenna directions & sectorisation)

Propagation environment (propagation slope)

Soft handover overhead is related to the cell coverageoverlap and other cell interference level

Below simulated DL values

Load Calculation Examples


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Load factor for different services has to be calculated separately, total loadis then the sum of different services in the cell area

UL/DL single connection load examples are shown in the table below

For example 50 % UL load means on average 50 speech users or about 964 kbits/s users/cell in a 3-sector (1+1+1) configuration

Services UL Fractional Load DL Fractional Load

12.2 kbit/s 0,97% 1,00%

64 kbits/s 4,80% 6,21%

128 kbits/s 8,56% 11,07%384 kbits/s 22,89% 29,59%

Total Load 37,22% 47,87%

Total base station DL powerR99 traffic


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Total DL base station transmit power can be a limiting factor

in highly loaded cell

DL

CCCHN

j jSERVjj

jb

NDL

TOT

DL

PL

RW

NEPP

111

1 ,

0

where,

Lserv

is the pathloss of user j. The pathloss is defined as totalloss from BTS transmitter to the receiver

PCCCHis the total common control channel power

Example - Total DL power and load


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Total DL power increases exponentially when the 100% load is approached

Higher common control channel allocation consumes larger part of DL power

4 W CCCH & 50% load Total power 10.5 W

8 W CCCH & 50% load Total power 18.5 W

PtxTotal with different common channel power

4.0 4.3 4.75.0 5.4

5.9 6.47.0 7.7

8.5 9.4

10.511.8

13.415.4

17.9

21.3

26.0

33.1

8.0 8.5 9.1 9.7

10.311.111.9

12.914.0

15.316.7

18.520.6

23.1

26.3

30.4

35.9

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

0%

5%

9%

14%

18%

23%

27%

32%

36%

41%

45%

50%

54%

59%

64%

68%

73%

77%

82%

86%

91%

Downlink DCH load

PtxTotal

4 W

8 W


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ExampleCapacity analysis


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Speech traffic of 25 Erlangs corresponds average of 25 calls

in the cell Average speech load: UL24%, DL25%

Maximum cell power 20 W with 2 W pilot allows maximum DLload of 74% in the example cell

In average 49% load margin available for NRT data in DL 49% / 11.07% * 128 kbps = 566 kbps

In average 566 kbps available for NRT data

Module Contents


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Basic Traffic Model



RNCDimensioning

IubDimensioning

Iu

Dimensioning

IurDimensioning

+



HSDPA capacity

HSUPA capacity

Radionetw

ork

Acc

essnetwork

HSDPA CapacityIntroduction


123/132



GeometryFactor

TotalTransmitPower

SpreadingFactor

Orthogonalityfactor

TransmittedHS-PDSCH

power

GP

PSFSINR

tot

PDSCHHS

11

16

HSDPA dimensioning can be done based on

Requirement to achieve minimum HSDPA throughput at cell edge

Determined from link budget analysis, SINR at cell edge

Requirement to achieve average HSDPA throughput across the cell

Determined by SINR distribution analysis

HSDPA capacity depends on

Available power for HSDPA

Channel conditions

Cell range (pathloss)

Interference level over cell area

HSDPA featuresand configuration

HSDPA CapacityHSDPA power calculation


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BTS allocates all unused DL power to HSDPA

All the power available after DCH traffic, HSUPA control channels andcommon channels can be used for HSDPA

HSDPA power is shared dynamically between HS-SCCH andHS-PDSCH

DCHtxCCHWBTS PPPPtxHSDPA _max_

HSDPA CapacityG-Factor


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The G Factor reflects the distance between the MS and BSantenna thus setting a value for G factor means making

assumptions on user location. A typical range is from -5dB (Cell Edge) to 20dB

Typical G factor distributions (CDF) coming from Nokiasimulation tools as well as operator field experience are

represented in the following chart:

-20 -10 0

G-factor [dB]

Cumulativedistr

ibutionfunction[%]

10 20 30 400

10

20

30

40

50

60

70

80

90

100

Macrocell(Wallu)

Veh-A/Ped-A

Macrocell

(Vodafone)Veh-A/Ped-A

Microcell

(Vodafone)Ped-A

)1

1(16 G

PSF

SINRP totHSDPA

othernoise

own

IP

IG

HSDPA capacity and RAN features


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HSDPA capacity is influenced by capabilities of the networkand the UE

Number of codes (5, 10, 15) Higher peak bit rate in good conditionsHigher cell throughput

Code multiplexing (multiple 5 code UEs can utilise up to 15 codes) Higher spectrum efficiency

5 Codes 10 Codes 15 Codes

1.2 Mbps

1.7 Mbps

1.8 Mbps

2.0 Mbps

2.2 MbpsNo code - mux (10/15 code UEs)

Code - mux (5 - code UEs)

Cell capability

0

500

1000

1500

2000

2500

0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% 55% 60%

DCH powe r, % of PA

HSDPAcellthroughput

5 codes

15 codes

10 codes

Cell size and HSDPA cell throughput


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Cell size has an effect on HSDPA cell throughput when celledge pathloss is high (large cell or indoor users)

Increase of BTS power has only limited effect on cellthroughput

0

200

400

600

800

1000

1200

1400

100 105 110 115 120 125 130 135 140 145 150 155 160

Cell edge pathloss, dB

HSDPAcellthroughput

DCH load 10%&20W

DCH load 30%&20W

DCH load 50%&20W

DCH load 10%&40W

DCH load 30%&40W

DCH load 50%&40W 5 codes


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Module Contents


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Basic Traffic Model



RNCDimensioning

IubDimensioning

Iu

Dimensioning

IurDimensioning

+



HSDPA capacity

HSUPA capacity

Radionetwork

Acc

essnetwork

HSUPA CapacityHSUPA Cell Throughput

M th d l


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C/I = Eb/NoProcessing Gain

C/I is translated to HSUPA bit rate using the Eb/No

look-up table derived from link level simulations

ia

IC

Nj

j

jj

UL

1

)/(

11

1

1

0

2

4

6

8

10

12

0 20 40 60 80 100

Uplink Load (%)

Increase

inInterference

(dB)

Example Target

Uplink Load

Uplink Load generated

by R99 DCH

Uplink Load available

for HSUPA UE

Methodology

The uplink load is shared between HSUPA and R99 DCH uplink load

Uplink load is translated to uplink C/I using the uplink load equation UEs distribution inside the cell impacts on possible C/I thus it also impacts on cell

throughput

By default, each Ue is allocated an equal share of UL Load.

The saving in uplink load is re-distributed to the UE closer to the cell

Layer 1

Bit Rate

TTI

(ms)

Physical

Channel

Eb/No with

RxDiv

1920.0 10 2*SF2 0.5

1440.0 10 2*SF2 0.1

384.0 10 1*SF4 0.9

256.0 10 1*SF4 1.1

128.0 10 1*SF8 1.9

HSUPA CapacityExample


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If maximum 80% load is possible through celland assuming 5 simultaneous users.

E.g. DCH load 30 %(80%-30%)/5 = 10% per user(equal share assumption)

Example Eb/Nos are ITU Vehicular-A 30 km/h

65.0_ LPowerRiseUULi

Layer 1

Bit Rate

TTI

(ms)

Physical

Channel

Eb/No with

RxDiv

1920.0 10 2*SF2 0.5

1440.0 10 2*SF2 0.1

1024.0 10 2*SF2 0.2

512.0 10 2*SF4 0.6

384.0 10 1*SF4 0.9

256.0 10 1*SF4 1.1

128.0 10 1*SF8 1.9


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Thank you !

idea wcdma

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