W CDMA Lectures

8/11/2019 W CDMA Lectures

http://slidepdf.com/reader/full/w-cdma-lectures 1/387

S-72.238 Wideband CDMAsystems (2 cr.)

Responsible teacherKalle Ruttik

Room 205 Otakaari 8.

Phone: 451 2356.

Email: [email protected]



Goals of the course

• To present the driving factors and ideas behind thedevelopment of third generation cellular system standards.

• To describe the characteristics of CDMA, its possibilities

and problems in a multipath radio channel.

• To facilitate to understand of the WCDMA concept as

applied to the UMTS UTRA.

• To give an overview of the UMTS core and radio access

network.



Literature

The Course book: “WCDMA for UMTS. Radio Access For

Third Generation Mobile Communications.” Edited by:

H.Holma, A. Toskala. 2000, John Wiley&Sons. 322 pp.

Also good reading:

“UMTS Networks. Architecture, Mobility and Services.” H.

Kaarinen et.al.. 2001,John Wiley&Sons. 302 pp.

“Radio Network Planning and Optimisation for UMTS.”

J.Laiho. et. al.. 2002. John Wiley&Sons. 484 pp.

“The UMTS Network and Radio Access Technology.” J.P.Castro. 2001,John Wiley&Sons. 354 pp.

Specifications http://www.3gpp.org/



Outline of the course

1. Introduction to 3G cellular systems. Cellular propagation environment for 3G

radio links. Standardisation process.

2. Evolution from GSM to UMTS. UMTS network Architecture.

3. Packet traffic modelling.

4. Introduction to WCDMA: modulation demodulation methods made available at

the network level: handover, power control.

5. Radio Access Network architecture (chapter 5).

6. Physical layer (chapter 6).

7. Radio interface protocols (chapter 7).

8. WCDMA radio network planning (chapter 8).

9. Radio Resource management (chapter 9).

10. Packet access (Chapter 10).

11. Physical Layer performance (Chapter 11).



Outline of the lecture

• History of mobile communication.• Radio Communication peculiarities.

• Vision for UMTS.• Standardisation process.



History of mobile communications

• 1873 Maxwells equations.

• 1886 Hertz demonstrates the existence of radio waves.

• 1895 Marconi patents the wireless telegraph.

• 1900 Fessenden succeeds to transmit voice over radio:

– Ship to shore radio communication,

– Aircraft to ground radio communication.

• 1921 Police car radios, Detroit.

– First private radio telephone systems.

• 1946 First public radio telephone systems, St. Louis.

• Introduction of HF radio telephones.

• Introduction of VHF radio telephones.

• 1970 Introduction of Finnish ARP-network



History of mobile communications 2

1979 Introduction of AMPS cellular networks.

1980 POCSAG paging standard.1982 INMARSAT services.

1982 NMT450 cellular networks.

1984 TACS cellular networks,

CT1 cordless telephones.1985 CT2 cordless telephones.

1991 GSM cellular networks.

1992 DECT cordless telephones.

1995 First CDMA network.1995 ERMES paging network

1996 TETRA networks.

1991 Development of FPLMTS/IMT2000 and UMTS standards.



Fundamentals of Radio communications• Radio waves as a transmission medium

• Time dependent electromagnetic fields produce waves that radiate from the

source to the environment.• The radio wave based radio communication system is vulnerable to the

environmental factors: mountains, hills reflectors, … .

• The radio signal depends on the distance from the base station, the wavelength

and the communication environment.• Main problems of radio communication are:

– Multipath propagation phenomena

– Fading phenomena

– Radio resource scarcity



Multipath propagation

• Advantage: connection in case of Non-line-

of-Sight.

• Fluctuation in the received signal’s

characteristics.

The factors affecting radio propagation:

• Reflection: collision of the electromagnetic

waves with an obstruction whose

dimensions are very large in comparisonwith the wavelength of the radio wave.

Reflected radio waves.

• Diffraction, shadowing: collision of the

electromagnetic waves with an obstruction

which is impossible to penetrate.

• Scattering: collision of the radio wave with

obstructions whose dimensions are almost

equal to or less than the wavelength of radio

wave.





Channel Bandwidth

Impact of wide bandwidth• The number of taps increases.

• New tap amplitude statistics areneeded.



Wideband Channel Modelling

• The channel can be represented as a

sum of flat fading Rayleigh- or Rician

components.

– Each component has its own dopplerspectrum

– Equivalent model is tapped delay line

• Geographical area from where

multipath components arrive to the

receiver can be divided into elliptical

zones.

• The with of the zone gives enough

small delay variation of the zone.

• The transmission function for a zone

is mostly constant.

tx rx

A1

A

A

noisesource

noise

source

Σ

90

fast fading generator

fastfadinggenerator

fastfadinggenerator

2

N

a1s

a2s

aNs

( )1 2

0

( , ) k M

j t k k

k

h t h e πν

λ δ λ τ −

== −∑



Signal amplitude in the channel

Yhteysvälin vaimennus (Path Loss)

-130

-120

-110

-100

-90

-80

-70

-60

0 20 40 60 80 100 120 140 160 180 200

matka (m)

a m p l i t u d i ( d B )

impulssivaste

-140

-130

-120

-110

-100

-90

-80

-70

4 0 0

4 4 0

4 8 0

5 2 0

5 6 0

6 0 0

6 4 0

6 8 0

7 2 0

7 6 0

8 0 0

8 4 0

8 8 0

9 2 0

9 6 0

1 0 0 0

1 0 4 0

1 0 8 0

1 1 2 0

1 1 6 0

1 2 0 0

1 2 4 0

1 2 8 0

1 3 2 0

1 3 6 0

1 4 0 0

1 4 4 0

1 4 8 0

1 5 2 0

1 5 6 0

1 6 0 0

viive (ns)

d B



Examples of channel models used in

GSM developmentBad urban

i 1 2 3 4 5 6

τi / µs 0 0.3 1.0 1.6 5.0 6.6

Pim /dB −2.5 0 −3.0 −5.0 −2.0 −4.0

class class class class class class

Typical urban

i 1 2 3 4 5 6

τi / µs 0 0.2 0.5 1.6 2.3 5.0Pim /dB −3.0 0 −2.0 −6.0 −8.0 −10.0

class class class class class class

Rural area

i 1 2 3 4 5 6

τi / µs 0 0.1 0.2 0.3 0.4 0.5

Pim /dB 0 −4.0 −8.0 −12.0 −16.0 −20.0

Rice class class class class class

t

f

0 1 2 3 4 5 6 µs

tap coefficient

distributions



UMTS user environments

suburban,rural macrocells

Satellite cells

urban,microcells

indoor,

picocells



Cellular radio communication principles

• Public radio communications should

offer duplex communication.

• The signal strength deteriorates togetherwith distance.

• Every transmitter can offer only limited

amount of simultaneous radio links to the

end-users.

• Cellular concept:

– large area is divided into a number of

sub-areas - cells.

– Each cell has its BS which is able to

provide a radio link for number of

simultaneous users.

A clusters of cells in a cellular network



Architecture of mobile systems

• Problems

– Interference due to the cellular structure, inter- and intra-cell interference

– Mobility handling

– Cell based radio resource scarcity

Basic structure of a cellular network

SwitchingNetwork

FixedNetwork

Base Stations

Mobile Stations



Interference

• Assume the asynchronous users sharing the

same bandwidth and using the same radio

base station in each coverage area or cell.• Intra-cell/co-channel interference due to the

signal from the other users in the home cell.

• Inter-cell/adjacentchannel interference due to

the signal from the users in the other cell.

• Interference due to the thermal noise.

Inter-cell and intra-cell interference in a cellular system

l

Intra-cell Interference

Inter-cell Interference

Methods for reducing interference:

• Frequency reuse: in each cell of cluster pattern different frequency is used– By optimising reuse pattern the problems of interference can be reduced significantly,

resulting in increased capacity.

• Reducing cell size: in smaller cells the frequency is used more efficiently.

• Multilayer network design: macro-, micro-, pico-cells



Signal and interference

Signal received at the BS

Spectral density of

interference from other

users in the cell

Spectral density of

interference from users in

other cells

Thermal noise spectral density

Energy per bit of data

data rate

I W=(n-1)P

I W

j

n

P

I j

I n

P

N 0

Rb

E b

bbP E P =

( ) W

R

I

E

N I I

PCIR bb

n j 00

=++

=



Cell breathing

• Outcome

– system capacity sensitive to instantaneous conditions in the cell

– for “bad” users configuration the demanded capacity will be more

than available capacity

– all users increase their transmission power

– some users reach their available power and CIR requirement for

them will be violated

• Reasons

– same spectrum for all users– power control

– interference depends on location

of users

0 200 400 600 800 1000−10

−5

0

5

10

15

20

25

30

Distance from BS [m]

P s , i

[ d B m ]

N = 40

N = 50

N = 60

N = 70

N = 80



Mobility

• Mobility provides the possibility of being reachable anywhere and any time for

the end-user

The mobility is provided through:

• Handover: gurantees that whenever the mobile is moving from one BSarea/cell to another, the signal is handed over to the target BS.

When there is no continuous active radio link between mobile and BS the mobility

is supported by:

• Location update: user registers in the network that it can be found in givenarea. Mobile always initiates the location update procedure.

• Paging: indication to the user about the the need for transaction. Paging

procedure is always initiated by the network.



Cellular generations

1G- Basic Mobility- Basic Services- Incompatible

2G- Advanced Mobility (Roaming)- More Services (Data Presence)- More Global solution

3G- Seamless Roaming- Service Concepts & Models- Global Radio Access

- Global Solution

1980 1990 2000

1G Systems: NMT, AMPS, TACS.

2G Systems: GSM, DAMPS,

IS-136, IS-95,PDC.

3G Systems:

WCDMA

(UMTS,UTRA

FDD+TDD)

cdma2000EDGE



Vision for UMTS

• Well specified system with major interfaces open and standardised. The

specifications generated should be valid world-wide.

• Added value to the GSM. However, in the beginning the system must be

backward compatible at least with GSM and ISDN.• Multimedia and all of its components must be supported throughout the system

• The radio access of the 3G must provide wideband capacity be generic enough

in order to become available world-wide. The term “wideband” was adopted to

reflect the capacity requirements between 2G narrowband capacity and thebroadband capacity of the fixed communications media.

• The services for end-users must be independent from radio access technology

details an the network infrastructure must not limit the services to be

generated. That is, the technology platform is one issue and the services using

the platform are totally another issue.



User aspects of UMTS

• reaching mass market

• common standards enabling

– low cost mass production

– open interfaces

• global standards

• public and private networks

• ubiquitous services

Mobile aspects of UMTS

• terminal mobility

• personal mobility

• service mobility

Telecommunication aspects of UMTS

• System providers:

– connection everywhere

– interconnection between networks

– billing and accounting functions for all various

interest

– security– Network management is cost efficient and

spectrum efficient manner

• Service choice and flexibility thorough a large

variety of service providers and network

operators.• Simple and user friendly access.

• Personalised of user service profiles and user

interfaces.

• Transparent services.• Universal accessibility.

• Convergence of telecommunications, computer

technology, and content provision

• Multimedia services



Examples of new services or applications

Information services:

• Interactive shopping,

• On-line equivalents of printed media,

• Location based broadcasting,

• services.

Educational services:

• Virtual schools,

• On-line library,

• Training.

Entertainment services:

• audio on demand,

• games on demand.

Community services

• emergency services,

• governmental procedures.

Business information:

• mobile office,

• virtual workshop.

Special services:

• tele-medicine,

• security monitoring,

• instant help line,

• personal administration.

Communication services:

• video telephony,

• video conference,

• personal location.

Business and financial services

• virtual banking,

• on-line billing.



3G technical requirements• Bit Rate:

– Rural outdoor 144 kbps (500 km/h).

– Suburban outdoor 384 kbps (120 km/h) .

– Indoor 2 Mbps (10 km/h).

• Variable bit rate capability: granularity, circuit and packet bearers.

• Service Multiplexing.

• Varying delay and quality of service requirements. ( priorities of traffic).

• Handover: seamless between the cells and different operators. Co-existence

with and handover to 2G systems (with WCDMA to GSM).• Support of asymmetric traffic.

• High spectrum efficiency.

• Coexistence of FDD and TDD modes.



Basic telecommunication services• Bearer services: which are telecommunication services providing the capability

of transmission of signals between access points.

• Teleservices: which are telecommunication services providing the complete

capability, including terminal equipment functions, for communication between

users according to protocols established by agreement between network operators.– Some teleservices are standardised because that interworking with other systems have been

recognised as a requirement.

• Supplementary services:A supplementary service modifies or supplements a

basic telecommunication service. Consequently, it cannot be offered to a user as a

stand alone service.

TE MT PLMN

possible

transitnetwork

Terminating

network

Bearer services

Teleservices

UE

UE: User Equipment

MT: Mobile Termination

TE: Terminal Equipment

TAF: Teminal Adaption Function

TETAF



Definitions (1)

• Basic telecommunication service : this term is used as a common reference to both bearer services

and teleservices.

• Bearer service : is a type of telecommunication service that provides the capability of transmission of

signals between access points.

• Call : a logical association between several users (this could be connection oriented or connection

less).

• Connection : is a communication channel between two or more end-points (e.g. terminal, server etc.).

• Multimedia service : Multimedia services are services that handle several types of media. For some

services, synchronisation between the media is necessary (e.g. synchronised audio and video). A

multimedia service may involve multiple parties, multiple connections, and the addition or deletion of resources and users within a single call.

• Quality of Service : the collective effect of service performances which determine the degree of

satisfaction of a user of a service. It is characterised by the combined aspects of performance factors

applicable to all services, such as;– service operability performance:

– service accessibility performance;– service retention performance;

– service integrity performance;

– other factors specific to each service.



• Service Capabilities: Bearers defined by parameters, and/or mechanisms needed to realise services.

These are within networks and under network control.

• Service Capability Feature: Functionality offered by service capabilities that are accessible via the

standardised application interface

• Services: Services are made up of different service capability features.

• Supplementary service : is a service which modifies or supplements a basic telecommunication

service. Consequently, it cannot be offered to a user as a standalone service. It shall be offered

together with or in association with a basic telecommunication service. The same supplementaryservice may be common to a number of basic telecommunication services.

• Teleservice; is a type of telecommunication service that provides the complete capability, including

terminal equipment functions, for communication between users according to standardised protocols

and transmission capabilities established by agreement between operators.

Definitions (2)



Bearer Services

• Bearer services provide the capability for information transfer between access

points and involve only low layer functions.

• The user may choose any set of high layer protocols for his communication.

• A communication link between access points provides a general service forinformation transport.

• The communication link may span over different networks.

• Bearer services are characterised by a set of end-to-end characteristics with

requirements on QoS. QoS is the end-to-end quality of a requested service as

perceived by the customer.

• Requirements on the Bearer Services

– Information transfer:

• Traffic type: quaranteed/constant bit rate, non-quaranteed/dynamic variable bit rate, real

time dynamic variable bit rate with a minimum guaranteed bit rate.– Traffic characteristics: the user can require on of the following configurations

• Pont-to-point: uni-directional, bi-directional: symmetric, assymmetric.

• Uni-directional point-to-multipoint: multicast,broadcast.



Information quality

• Maximum transfer delay: Transfer delay is the time between the request to

transfer the information at one access point to its delivery at the other accesspoint.

• Delay variation: The delay variation of the information received information

over the bearer has to be controlled to support real-time services.

• Bit error ratio: The ratio between incorrect and total transferred informationbits.

• Data rate: The data rate is the amount of data transferred between the two

access points in a given period of time.



UMTS QoS Classes

• Conversational: end-to-end delay is low and the traffic is symmetric of nearlysymmetric.

– Speech, Video telephony, … .

• Streaming: data is transferred such that it can be processed as a steady continuous

stream.

– Video, audio, … .

• Interactive: interaction between human or machine and remote equipment.

– Web browsing, tele-mechanics, ... .

• Background: non real time data traffic.

– email … .

Errortolerant

Errorintolerant

Conversational(delay <<1 sec)

Interactive(delay approx.1 sec)

Streaming(delay <10 sec)

Background(delay >10 sec)

Conversationalvoice and video

Voice messagingStreaming audio

and videoFax

E-mail arrivalnotificationFTP, still image,paging

E-commerce,WWW browsing,Telnet,

interactive games



QoS requirements

Real Time (Constant Delay) Non Real Time (Variable Delay)

Operating

environment

BER/Max Transfer Delay BER/Max Transfer Delay

Satellite

(Terminalrelative speed toground up to1000 km/h forplane)

Max Transfer Delay less than 400 ms

BER 10-3 - 10-7(Note 1)

Max Transfer Delay 1200 ms or more(Note 2)

BER = 10-5 to 10-8

Rural outdoor(Terminalrelative speed toground up to 500km/h) (Note 3)

Max Transfer Delay 20 - 300 ms

BER 10-3 - 10-7(Note 1)


BER = 10-5 to 10-8

Urban/ Suburban

outdoor(Terminalrelative speed toground up to 120km/h)


BER 10-3 - 10-7(Note 1)


BER = 10-5 to 10-8

Indoor/ Lowrange outdoor(Terminalrelative speed toground up to 10

km/h)


BER 10-3 - 10-7

(Note 1)


BER = 10-5 to 10-8

NOTE 1; There is likely to be a compromise between BER and delay.NOTE 2; The Max Transfer Delay should be here regarded as the target value for 95% of the data.NOTE 3; The value of 500 km/h as the maximum speed to be supported in the rural outdoor environment

was selected in order to provide service on high speed vehicles (e.g. trains). This is not meantto be the typical value for this environment (250 km/h is more typical).



End-user performance expectation

conversational/real time traffic

Medium Application Degree of

symmetry

Data rate Key performance parameters and target values

End-to-end One-

wayDelay

Delay

Variationwithin a

call

Information

loss

Audio Conversational

voice Two-way 4-25 kb/s <150 msec

preferred

<400 msec limit

Note 1

< 1 msec < 3% FER

Video Videophone Two-way 32-384

kb/s

< 150 msec

preferred

<400 msec limit

Lip-synch : < 100

msec

< 1% FER

Data Telemetry

- two-way

control

Two-way <28.8

kb/s

< 250 msec N.A

Zero

Data Interactive games Two-way < 1 KB < 250 msec N.A Zero

Data Telnet Two-way

(asymmetri

c)

< 1 KB < 250 msec N.A Zero



E d P f E i



End-user Performance Expectations

- Streaming ServicesMedium Application Degree of

symmetry

Data rate Key performance parameters and target values

One-way

Delay

Delay

Variation

Information loss

Audio

High quality

streaming audio

Primarily

one-way

32-128

kb/s

< 10 sec < 1 msec < 1% FER

Video One-way One-way 32-384

kb/s

< 10 sec < 1% FER

Data Bulk data

transfer/retrieval

Primarily

one-way

< 10 sec N.A

Zero

Data Still image One-way < 10 sec N.A Zero

Data Telemetry

- monitoring

One-way <28.8

kb/s

< 10 sec N.A Zero



Teleservices

• A teleservice can be viewed as set of upper layer capabilities utilising the

lower layer capabilities.

• Teleservices can be single media or multimedia services.

• Multimedia services are classified:

– multimedia conference services,

– multimedia conversational services,

– multimedia distribution services,

– multimedia retrieval services,

– multimedia messaging services,

– multimedia collection services.

• The terminal and network should support the service.

• The principle of the network design has been that upper layer and lower layerare made as independent as possible. (Layers are understood accordingly OSI

model).



Service Capability features

• Services Capability Features are open, technology independent building blocks

accessible via a standardised application interface.

• Application/Clients access the service capability features via the standardised

application interface.

• Framework service capability features: these shall provide commonly used

utilities, necessary for the non-framework service capability features to be

accessible, secure, resilient and manageable.

– Authentication, User-Network Authentication, Application-Network Authentication,

User-Application Authentication, Authorisation, Application-Network Authorisation,User-Application Authorisation, Registration, Discovery, Notification. TS22.121.

• Non-Framework service capability features: these shall enable the applications

to make use of the functionality of the underlying network capabilities (e.g. User

Location service capability features).

– Session Control, Security/Privacy, Address Translation, Location, User Status, Terminal

Capabilities, Messaging, Data Download, User Profile Management, Charging.

• When applications use the generic service capability features, these applications

become independent of (portable over) underlying service capabilities.

i i



Execution environment

• The execution environment is a set of standardised capabilities that shall allow the

support of home environment/serving network (HE/SN) specific services (i.e. both

applications, teleservices and supplementary services). The execution environment

shall be distributed between the IC card, terminal and network nodes

• Building blocks of execution environment:– A standardised content description language for support of HE/SN specific user interfaces

(both for information output and user input).

MobilityMan.

Call

Control

BearerControl

Service

Execution Environment

Terminal/IC card

/Session

Logic 1ServiceLogic 2

ServiceLogic N

– A standardised procedural language for

support of HE/SN specific scripts. This

language shall be common to all types of platforms.

• The scripts could be used for e.g. improving

the user interface, adding new features to the

terminal like the latest version of a codec,

controlling the execution of a service.

– Standardised application programming

interfaces for opening platform resources and

capabilities to the scripts written with the

standardised procedural language.



3GPP standardised user service capabilities

• Tele services:

– Speech.– Emergency call.

– Short Message Service.

– Cell Broadcast service CBS.

• Bearer Services:

– Circuit-switched data.

– Packet-switched data.

– Defined by their attributes:

• Information transfer

attributes.

– Information transfer rate,

Information transfer

characteristics … .

• Information quality

attributes.

– Bit error ratio, Maximum

transfer delay Delayvariation … .

• Supplementary services:

– Defined in GSM R'99. Examples:• Call Forwarding

• Advice of Charge.

• Explicit Call transfer.

• Service capabilities:

– Mobile Service ExecutionEnvironment.

– Location Services.

– SIM application toolkit.

• GSM systems features:

– Network identity and time

zone.

– Unstructures supplementary

service data.

UMTS R99 will standardise the technical means by which a UE may implement the

following UE Service Capabilities.



Regulation

Legal-administrative aspects:

• Spectrum allocation.

• Technical standardisation.

Economic-political aspects:

The spectrum made available such

that:

• System providers and users aresatisfied.

• Spectrum efficiently used.

Regulation

Technical-engineeringfactors

Factors in the regulation process

Legal-administrative

factors

Economic-political

factors



Specification process for 3G

• In Europe 3G has become UMTS (Universal Mobile Telecommunication

System), following the ETSI perspective.

• In Japan and US IMT-2000 (International Mobile Telephony 2000). The namecomes from the International Telecommunication Union (ITU) development

projects.

• Evolution of IS-95 system is covered under the name CDMA2000.

• ITU FPLMTS project - promotion of common architectural principles amongthe family of IMT-2000 systems.

• Different short-term targets.

– Europe: need for commercial mobile data service.

– Far East: need for additional spectrum for speech services.



3G Spectrum

In Europe:

WCDMA-FDD 2110-2170 MHz downlink. 1920-1980 MHz uplink,WCDMA-TDD 1900-1920 and 2020-2025.

PCS MSS

PHS IMT2000 MSS

GSM1800 IMT200 MSS

IMT200 MSS IMT2000

IMT200

IMT200 MSS

MSS

MSS

MSS

1900 2000 2100 2200

USA

JAPAN

EUROPE

ITU

MHz



EU projects

• Several pre-standardisation research projects:

– 1992-1995 RACE MoNet project (financed by EU)

• System Techniques.

• System integration

• Modelling methods for describing function allocation between the radio access and core

parts of network.

– 1995-1998 ACTS FRAMES project.

• Multiple access method.

• Participants: Nokia, Siemens, Ericsson, Universities …

• Single air interference proposal for ETSI: input 13 proposals, output 2 modes.

RACE Ibasic studies

RACE IIATDMACODIT

ACTS/FRAMESFMA1:WTDMAFMA2:WCDMA

ETSIConceptgroups

ETSI decisionWCDMA for

FDD operation

1988 1992 1995 1997 1998

ETSI T h l l i (1)



ETSI Technology selection (1)

• WCDMA

– The basic system features

considered

• Wideband CDMAoperation with 5 MHz,

• Physical layer flexibility for

integration of all data rates

on a single carrier,

• Frequency reuse 1.

– The enhancements covered

• Transmit diversity,

• Adaptive antennae

operations,

• Support for advanced

receiver structures.

• WB-TDMA/CDMA

– The basic system features considered

• Equalisation with training sequences in

TDMA bursts,• Interference averaging with frequence

hopping,

• Link adaptation,

• Two basic burst types,

• Low reuse size.

– The enhancements covered

• Inter-cell interference supression,

• Support of adaptive antennas,

• TDD operation,

• Less complex equalisers for large delay

spread environment.

ETSI T h l l i (2)



ETSI Technology selection (2)

• WB-TDMA/CDMA


• TDMA burst structure with midamble

for channel estimation,

• CDMA concept applied on top of the

TDMA structure for additionalflexibility,

• Reduction of intracell interference with

multiuser detection,

• Low reuse size (< 3)

– The enhancement covered included

• Frequency hopping,• Inter-cell interference cancellation,

• Support of adaptive antennas

• Operation in TDD mode,

• Dynamic Channel Allocation.

• OFDMA


• Operation with slow frequency hopping

with TDMA and OFDM multiplexing,

• A 100kHz wide bandslot from theOFDM signal as the basic resource unit,

• Higher rates build by allocating several

bandslots, creating a wideband signal,

• Diversy by dividing information over

several bandslots.

– The enhancement covered included

• Transmit diversity,

• MUD,

• Adaptive antennas solution.

• ODMA (opportunity driven MA)

– terminal outside of cell coverage use

other terminals as retransmitters.



UMTS standardisation procedure

3GPP is a “umbrella” aiming to form compromised standards by taking into account,

political, industrial, and commercial pressures from local specification bodies:

ETSI European Telecommunication Standard Institute /Europe

ARIB Association of Radio Industries and Business /Japan

CWTS China Wireless Telecommunication Standard group /China

T1 Standardisation Committee T1 Telecommunications /US

TTA Telecommunication Technology Association /Korea

TTC Telecommunication Technology Committee /Japan

3GPP

ETSI

ARIB TTAT1P1 TTC

CWTS

3GPP l t



3GPP evolvement

• Release 4:

– Separation of user data flows and control mechanisms,

– Narrowband TDD with 1.28 Mchips/s,

– Position location functionality.

• Release 5:– End-to-end packet switched cellular network using IP,

– Downlink data rate more than 10 Mbits/s.

– GERAN.

Va ria nt Ra dio a c c e ss S witc hing 2G Ba sis

3G (US ) WCDMA, EDGE, IS 41 IS - 95, GS M1900,

CDMA2000 TDMA

3G (Europe) WCDMA, GSM, E Advanc ed GSM NGSM900/1800

an d pac ket core

3G (Ja pa n) WCDMA Adva nc e d GS M NP DC

an d pac ket core

Different switching systems can becombined with different radio access

parts.

• Release 99:

– strong GSM presence:• Backward compatibility with GSM,

• Interoperation between UMTS and

GSM.

– UTRAN



WCDMA in ITU IMT 2000• 3GPP covers CDMA direct spread and TDD

• ITU provides references to 3GPP specifications and does not make

specifications of its own.

• Based on the standardisation ITU has the following grouping:

IMT200

TDMA CDMA

Single Carrier Multi-Carrier Direct SpreadMulti-Carrier TDD

3.84 Mcps 3.6864 Mcps 3.84 Mcps

1.28 Mcps



2G (GSM) vs 3G (WCDMA)WCDMA GSM

Carrier spacing 5 MHz 200 kHz

Frequency reuse factor 1 1-18Power control frequency 1500 Hz 2 Hz or lower

Quality control Radio resource management

algorithms

Network planning

(Frequency planning)

Frequency diversity 5 MHz bandwidth gives multipath

diversity with RAKE receiver

Frequency hopping

Packet data Load based packet scheduling Time slot based scheduling

with GPRS

Dowlink transmit

diversity.

Supported for improving downlink

capacity.

Not supported by the

standard but can be applied.



Evolution from GSM to UMTS




Evolutions form GSM to UMTS.• 3G network architecture.

• Service provision in UMTS.

Evolution types



Evolution types

• Evolution contains not only technical evolution but also expansion to network

architecture and services.

• Technical evolution: how network elements are developed and with witch

technology.

• Network evolution: in result of network element evolutions the generalfunctionality of the network is changing.

– Technical evolution different for different vendors.

• Service evolution: demand generated by the end-users that can be supported by

the technical features of the network.

2G 3G

Technical Evolution

Network Evolution

Service Evolution



Evolution of the wireless networks

SMS

9.6

UMTS

ED

GE

GPRS

HSCSD14.4

1998 1999 2000 2001 2002

10k

100k

1000k

64k

1k

C i r c u i t

P a c k e

t



Basic GSM network (1)

• Driving idea in GSM: to define several open interfaces.

– Operator may obtain different network components form different suppliers.

– Strictly defined interface determines how the functions are proceeding in the network

and which functions are implemented internally by the network element.

• GSM provides a means to distribute intelligence in the network. Network

divided into four subsystems:

• Network Subsystem (NSS): call control.

• Base station Subsystem (BSS): radio path control.

• Network Management Subsystem (NMS): operation and maintenance.

• Mobile Station (MS).

• Difference between 1G and 2G:

– Symmetric data transfer possibility.– Service palette adopted from Narrowband ISDN.



Basic GSM network (2)

BSS NSSBTS BSC

Um A

MSMSC/VLR GMSC

HLR/AuC/EIR

TRAU ISDNPSPDNPSTN

CSPDN

Network Management (NMS)

GSM Network elements



GSM Network elements

• MS: mobile equipment + subscriber data (Service Identity Module)• Base Station Controller (BSC):

– Maintains radio connections towards Mobile Station.

– Maintains terrestrial connection towards the NSS.

• Base Transceiver Station (BTS):

– Air interface signalling, ciphering and speech processing.

• Mobile Service Switching Centre (MSC):

– Call control.

– BSS control functions.

– Internetworking functions.

– Charging,

– Statistics,

– Interface signalling towards BSS and external networks.

• Serving MSC: BSS connections, mobility management, inter-working.• Gateway MSC: Connections to the other networks.

• Visitor Location Register (VLR): local store for all the variables and functions

needed to handle calls in the area related to VLR.

Value Added Service platform



p

• Value Added Service (VAS) platform: simple platform for supporting certain

type of services in GSM. (Short Message Service Centre (SMSC), Voice Mail

System (VMS))

– Use standard interface towards GSM. May or may not have external interfaces

towards other networks.

BSS NSSBTS BSC

Um A

MSMSC/VLR GMSC

HLR/AuC/EIR

TRAU ISDNPSPDNPSTN

CSPDN


VAS

Intelligent Network (IN)



Intelligent Network (IN)

• Intelligent network: a platform for creating and providing additional services.

– Enables service evolution.

– Changes in the GSM switching elements to integrate the IN functionality.

– Example pre paid subscription.

• IN adopted from fixed network.

– Not possible to transfer service information between networks.

BSS NSSBTS BSC

Um A

MSMSC/VLR GMSC

HLR/AuC/EIR

TRAU ISDNPSPDNPSTN

CSPDN


VAS

IN

IN CS-1 (capability set 1)



( p y )

Originating Basic Call State Model

(BCSM) for CS-1

1. O_Null & AuthorizeOrigination_Attempt

2. Collect_Info

1

3. Analyse_Info

4. Routing & Alerting

5. O_active

2

3

7

6. O_Exeption

10

4

5

6

8

9

Route_Select_Failure

O_Call_Party_Busy

O_No_Answer

O_Abandon

O_Disconnect

Orig. Attempt_Authorized

Collected_Info

Analyzed_Info

O_Answer

O_Mid_Call

7. T_Null & AuthorizeTermination_Attempt

8. Select Facility &Present_Call

12

9. T_Alerting

10. T_Active

11. T_Exeption

15

13

16

14

T_Abandon

Term._Attempt_Authorized

T_Answer

18

17

T_Called_Party_Busy

T_No_Answer

T_Mid_Call

T_Disconnect

Terminating BCSM for CS1

Incoming CallProcessing

Outgoing CallProcessing



BCSM

• BCSM is a high-level finite state machine description of call control function

(CCF) activities required to establish and maintain communication paths forusers.

• BCSM identifies points in basic call and connection processing when IN

service logic instances are permitted to interact with basic call and connection

control capabilities.

• Point In Call (PIC) identify CCF activities required to complete one or more

basic call/connection states or interest to IN service logic instances.

• Detection Point (DP) indicate points in basic call and connection processing at

which transfer of control can occur.

• Transition indicate the normal flow of basic call/connection processing fromone PIC to another.

• Events cause transitions into and out of PICs.

HSCSD



HSCSD

• The data throughput of the system is increased:

– Channel coding is improved (9.6 kb/s -> 14 kb/s).

• High Speed Circuit Switched Data (HSCSD).

– Several traffic channels can be used.

– Max data rate 40 -50 kb/s.

BSS NSSBTS BSC

Um A

MSMSC/VLR GMSC

HLR/AuC/EIR

TRAU ISDNPSPDNPSTN

CSPDN


VAS

IN

HW&SW Changes for HSCSD

GPRS



• General Packet Radio Service

(GPRS)

– For supporting packet switching trafficin GSM network. No voice channel

reservation.

– Support for asymmetric traffic.

• Requires new service nodes:

– Serving GPRS Support Node (SGSN).

– Gateway GPRS Support Node (GGSN).

• Can not guarantee the QOS.

BSS NSSBTS BSC

Um A

MSMSC/VLR GMSC

HLR/AuC/EIR

TRAU ISDN

PSPDNPSTN

CSPDN


VA

S

I

NHW&SW Changes for GPRS

GPRS Packet Core

SGSN GGSN

Gb

Internet

Other Data NW

EDGE (1)



EDGE (1)

• Exchanged Data Rates for Global/GSM Evolution (EDGE):

– New modulation scheme. (8 PSK)

– Different coding classes. Maximal data rate 48 kbps per channel.

• EDGE phase 1:– channel coding and modulation methods to provide up to 384 kbps data rate.

– One GPRS terminal gets 8 time slots. The channel should be good.

• EDGE phase 2:

– Guidelines for achieving high data speed for circuit switching services.

• Data rates achieved almost equal to the ones provided by UMTS.

• Data rates not available everywhere in the cell.

EDGE (2)



E-RAN NSSBTS BSC

Um A

MSMSC/VLR GMSC

HLR/AuC/EIR

TRAU ISDNPSPDNPSTN

CSPDN


VAS

INHW&SW Changes for EDGE

E-GPRS Packet Core

SGSN GGSN

Gb

Internet

Other Data NW

EDGE (2)

3G network R99 (1)



E-RAN CN CS Domain

BTS BSC

Um A

MSMSC/VLR GMSC

HLR/AuC/EIR

ISDNPSPDNPSTN

CSPDN


VAS

CAMEL

UTRAN CN PS Domain

BS RNC

Uu

UE

SGSN GGSN

Gb

MEXE

WAP

USAT

Iu

Iu

Internet

Other Data NW

( )

3G network R99 (2)



• New Radio interface.

• More suitable for packet data

support.

• Interoperability with GSM:

– GSM radio interface modified to

broadcast CDMA system

information. WCDMA networks

transfer also GSM data.

– Possibility to set 2G MSC/VLR to

handle the wideband radio access,

UTRAN.

• Customised applications for Mobile

network Enhanced Logic (CAMEL):

– Possibility to transfer serviceinformation between networks.

– In the future almost CAMEL will be

involved in all transactions between

networks.

• CS domain elements are able to handle

2G and 3G subscribers.

– Changes (upgrades) in MSC/VLR and

HLR/AC/EIR.

– For example SGSN• 2G responsible for mobility management

(MM) for packet connections

• 3G MM divided between RNC and

SGSN.

• Services– Initially 3G offers same services as 2G.

– Services transformed into PS domain.

• Trends

– Separation of connections in control and

services.

– Conversion of the network towards all

IP.

– Multimedia services provided by the

network.

3GPP R4 (2)



• The 3GPP R4 introduces separation of connection, its control, and services forCN CS domain.

• Media Gateway (MGW): an element for maintaining the connection and

performing switching function when required.

• MSC server: an element controlling MGW.

• Packet switched voice (Voice Over IP).

– The CS call is changed to the packet switched call in MGW.

– For higher uniformity the CS and PS domain is mediated by IP Multimedia

Subsystem.

• CAMEL will have a connection to the PS domain elements.

3GPP R4 (1)



GERAN CN CS Domain

BTS BSC

Um

MSMGW MGW

MSC Server

ISDN

PSTN CSPDN


UTRAN CN PS Domain

BS RNC

Uu

UESGSN GGSN

Iu

IP, Multimedia

HSS V

AS

C

AMEL

MEXE

WA

P

USAT

IMS

3GPP R5 (All IP)

N k M (NMS)



• Network looks to the users always same

– Development inside the network

– New transport technology: R99 ATM based; R4, R5 IP based.

• All traffic from UTRAN is supposed to be IP based.

GERAN

BTS BSC

Um

MSISDN

PSTN CSPDN


UTRAN CN PS Domain

BS RNC

Uu

UE

SGSN GGSN

Iu

IP, Multimedia

HSS VAS

CAM

EL

ME

XE

WAP

US

AT

IMS

IP/

ATM

IP/ ATM

IP/ ATM

Future trends



• Techniques:

– Further separation of the user plane from the control plane.

– Towards packet switching network.

– Transparency of access technologies. Greater emphasis to services and quality.– 4G ?

• Data rate ~20 Mbps (200 Mbps)

• Self planning dynamic topologies.

• Integration of IP.

– OFDM• Services

– Location based services. Many services existing at the same time at different

resolution.

– Separation of users:

• Commercial.

• Private users.

• Private users with specific needs.



3G Network architecture

• 3G is to prepare a universal infrastructure able to carry existing and future

services.• Separation of access technology, transport technology, service technology.

• The network architecture can be divided into subsystems based on the nature

of traffic, protocol structures, physical elements.

• Conceptual network model

• Structural network model

• Resource management architecture

• UMTS service and bearer architecture

Conceptual network model



• Protocol structure and responsibilities divided as:

– access stratum: protocol handling activities between UE and access network,

– non-access stratum: protocol handling activities between UE and Core Network,

• Stratum is the way of grouping protocols related to one aspect of the services

provided by one or several domains. (3GPP spec. TR 21-905)

USIM MobileEquipment

AccessNetwork

ServingNetwork

TransitNetwork

Cu YuIuUu

Access Stratum

Home

Network

PS Domain

CS Domain

Non-Access Stratum

User Equipment Domain

Access NetworkDomain

Core Network Domain

Infrastructure Domain

• Based on nature of traffic:

– packet switched (PS)

– circuit switched (CS)

• Domain is a highest level

of group of physical

entities and the defined

interfaces between such

domains. (3GPP spec. TR

21-905)

UMTS architecture domains



User Equipment domain: dual mode and multi-mode handsets, removable smart

cards … .

• Mobile Equipment (ME) domain:

– Mobile Termination (MT) entity performing the radio transmission and related

functions

– Terminal Equipment (TE) entity containing the end-to-end application.

• User Service Identity Module (USIM) domain:

– contains data and procedures to unambiguously and securely identify itself.Infrastructure domains:

• Access network domain: physical entities managing the access network

resources and provides the users with mechanisms to access the core network.

• Core network domain: physical entities providing support for the network

features and telecommunication services: management of user location

information, control of network features and services, switching and

transmission.



Core network domains

• Serving Network (SN) domain representing the core network functions

local to the user’s access point and location changes when user moves.• Home Network (HN) domain representing the core functions

conducted at a permanent location regardless of the user’s access point.

– The USIM is related by subscription to the HN.

• Transit Network (TN) domain: the CN part between the SN and theremote party.

UMTS stratums



USIM

MT - AN

MT/MEAccessNetworkDomain

ServingNetworkDomain

HomeNetworkDomain

AN - SN

“Access Stratum”

MT - SN

“Serving Stratum”

USIM - HN

SN - HN

“Home Stratum”

MT - SNUSIM - MT

“Transport Stratum”

USIM - MT

TEMT - AN

MT

AccessNetworkDomain

ServingNetworkDomain

TransitNetworkDomain

AN - SN

“Access Stratum”

TE - MT MT - SN

“Serving Stratum”

Application Stratum

Application

“Transport Stratum”

RemoteParty

MobileEquipment

Domain

Transport stratum



Transport stratum

Supports the transport of user data and network control signalling from other strata

through UMTS• consideration of physical transport formats used for transmission.

• Mechanisms for error correction and recovery.

• Mechanisms to encrypt data over the radio interface and in the infrastructure

part if required.

• Mechanisms for adaptation of data to use the supported physical format.

• Mechanism to transcode data to make efficient use of the radio interface.

• May include resource allocation and routing local to the different interfaces.

• The access stratum, which is specified to UMTS as the part of the trasnport

stratum.



Access stratum

• Consists of User Equipment (UE) and infrastructure parts, as well as access-

technique specific protocols between these parts.• Provides services related to the transmission of data over the radio interface

and the management of the radio interface to the other parts of UMTS.

The access stratum includes the following protocols:

• Mobile termination - Access network (MT-AN) protocol supporting transfer of

detailed radio-related information to coordinate the use of radio resources

between MR and AN.

• Access network - Serving Network (AN - SN) protocol supporting the access

from the SN to the resources provided by the AN. It is independent of the

specific radio structure of the AN.



Serving stratum

Consists of protocols and functions to route and transmit user of network

generated data/information form source to destination. The source anddestination may be within the same of different networks. It contains functions

related to telecommunication services, and includes:

• USIM - Mobile termination (USIM - MT) protocol supporting access to

subscriber-specific information to allow functions in the user equipment

domain.• Mobile Termination - Serving Network (MT -SN) protocol supporting access

from MT to the services provided by the serving network domain.

• Terminal Equipment - Mobile Termination (TE -MT) protocol supporting

exchange of control information between the TE and the MT.

Home stratum



• Consists of protocols and functions related to the handling and storage of subscription data and possibly home network specific services.

• Functions to allow domains other than the home network domain to act on

behalf of the home network.

• Functions related to subscription data management and customer care, as wellas billing and charging, mobility management and authentication.

The home stratum include the following protocols:

• USIM - Home Network (USIM - HN) protocol supporting co-ordination of

subscriber-specific information between USIM and HN.

• USIM - Mobile Termination (USIM - MT) protocol providing the MT with

access to user specific data and resources necessary to perform actions on

behalf of the home network.

• Mobile Termination - Serving Network (MT - SN) protocol supporting user

specific data exchange between the MT and the SN.• Serving Network - Home Network (SN - HN) protocol providing the SN with

access to HN data and resources necessary to perform its actions on behalf of

the HN.

Application stratum



• It represents the application process itself, provided to the end user.

• It includes end-to-end protocols and functions making use of services providedby the home, serving, and transport strata and necessary infrastructure

supporting services and/or value added services.

• The functions and protocols within the application stratum may adhere to

GSM/UMTS standards or may be outside the scope of the UMTS standards.

• End-to-end functions are applications consumed by users at the edge

of/outside the overall network.

• Authentication and authorised users may access the applications by using any

variety of available user equipment.

Structural Network Architecture



• UE user equipment

• ME mobile equipment

• USIM UMTS Service IdentityModule

• RAN Radio Access Network

– UTRAM UMTS RAN

– GERAN GSM/EDGE RAN

• Node B Base Station (BS)

• RNC Radio Network Controller

• RNS Radio Network Subsystem

• CS Core network

• Iur Interface between two RNS

UTRAN CN

RNS

CN CS Domain

CN PS Domain

Registers

RNS

BS

RNC

RNC

BS

BS

BS

UE

Uu Iu

Iur

UE

UE

3G MSC/VLR 3G GMSC

HLR/Au/EIR

SGSN GGSN



Resource Management Architecture• Communication Management: functions and procedures related to the user

connections.

• Mobility Management: functions and procedures related to mobility andsecurity.

• Radio Resource Management: algorithms related to the radio resource.

CM

RRM

MM MM MM

RRM

CM

Terminal (UE) UTRAN

NMS

CN

Communication Control

Mobility Control

Radio Resource Control

Mobility Control

Open Interface Uu Open Interface Iu

• The functions are related to the

control mechanisms:

– Communication Control.

– Mobility Control.

– Radio Resource Control.

UMTS Services



• 3G is designed as platform for

providing services

– The lower location the layer

has, the bigger is theinvestment in the network

elements.

Content Provider layer

Service Creation Layer

Network Element Layer

Physical Transmission Layer N e t w o r k

M a n a g e m e n t

S e c u r i t y F u n c t i o n s

– The higher location the layer has the bigger is the investment in people and ideas.

• Challenges: network management and securities.

• Methods for supporting service creation:– Virtual Home Environment: concept for personal service environment portability

across network boundaries and between terminals.

– Mobile Station Execution Environment: provides a standardised execution

environment in an MS, and an ability to negotiate its supported capabilities with a

MExE service provider, allowing applications to be developed independently of anyMS platform.

– CAMEL network feature: subscriber can use of Operator Specific Services (OSS)

even when roaming outside the HPLMN.

Service Provision, user point of view



• The concept of the VHE is such that users are

consistently presented with the same personalised

features:– Personalised services.

– Personalised User Interface (within the capabilities

of terminals).

– Consistent set of services from the user's perspective

irrespective of access e.g. (fixed, mobile, wireless

etc.) Global service availability when roaming.

USER

Personal

Service

Environment

Home

Environment

Provided and

Controlled by

User

Profile

Contains

1:N

Value Added

Service Provider

HE Value Added

Service Provider

N:N

• The User's personal service environment is a combination of services and

personalisation information (described in the user profile).

• The Home Environment provides services to the user in a managed way, possibly by

collaborating with HE-VASPs, but this is transparent to the user.• User may access services directly from Value Added Service Providers.

Implementation of Services

Applications / Clients



• Standardised Services: Vendor specific implementation using standardised

interfaces for service communication.

• Operator Specific services: Operator specific implementation of services by

using vendor specific toolkits with standardised interfaces.

• Other Applications: implementions using standardised interfaces to the ServiceCapabilities (Bearers, Mechanisms). The functionality offered by the different

Service Capabilities are defined by Service Capability Features.

• Within the terminals Service Capabilities are accessible via APIs, for example,

MExE.

Network

terminal viewclient nclient2 ...

API (e.g. MExE, SAT)

GSM/GPRS/UMTS protocol(*)

(*) ... standardisedinterfaces(+) ... to be standardised

GSM/GPRS/UMTS protocols, CAP/MAP(*)

SC 2 SC 3 SC n

MS functionality, Standardized Services

Servicecapabilities SC 1

ervice

apability

eatures (+)

Application

Interface

SC 4

Service

Capabilities

Application Interface

Proprietary

ServiceCapabilityFeature

Proprietary

ServiceCapability Pre-set by Standards, e.g.

CAMEL, SAT, MExE, access to

bearers etc.

Service

Capability FeaturesAccessible to Applications/Clientsvia Standardised Application

Interface

Built using ServiceCapability Features

Applications/ClientsProprietaryService

Personal Service EnvironmentPersonal Service Environment(Customised/Portable)

Standardised

U R i f VHE



User Requirements for VHE

• The Personal Service Environment describes how the user wishes to manage

and interact with their communications services.

• User Interface Profile:– Menu settings: menu items shown, menu structure, the placement of icons.

– Terminal settings: ringing tone and volume, font type and size, screen and text

colour, language, content types and sizes accepted.

– Network related preferences: language used for announcements … .

• User Service Profile:– A list of services subscribed to and references to Service Preferences for each of

those services if applicable.

– Service status (active/deactive).

• Use could have more than one service profile.

Home environment requirements for

VHE provision



• Control access to services:– depending on the location of the user, and serving network.

– on a per user basis e.g subject to subscription.

– depending on available service capabilities in the serving network, and terminals.

• Define the scope for management of services by the user, for services provided by the

HE.

• Manage:– service delivery based on for example end to end capabilities and/or user preferences.

– the prepaid accounts (e.g. increase, decrease the credit, or pass the information to an.

application which manages the credit).

– provision of services to users or groups of users.

• Request:– version of specific services supported in serving network and terminal.

– details (e.g. protocol versions and API versions) of available service capabilities supported in

the serving network, and terminals.

• Handle charging for services.• Inform the serving network:

– of the type of charging (i.e. prepaid or/and postpaid) for any required service.

– of the threshold set for a given service required by the user and charged on a prepaid account.

– how to manage a service for which the threshold has been reached.

• Deploy services to users or groups of users.

Serving Network requirements for VHE

i i



provisionThe serving network should not need to be aware of the services offered via the

home environment.

It shall be possible for the serving network to perform the following:

• The serving network shall support user access to services in the home

environment.• The serving network shall provide the necessary service capabilities to support

the services from the home environment as far as possible.

• Dynamically provide information on the available service capabilities in the

serving network.

• Provide transparent communication between clients and servers in terminalsand networks.

• Request the charging information (type of charging, threshold for prepaid

services and behaviour if the threshold is reached) for any service possibly

required by the user.

• Handle the call according to the instructions received by the home

environment regarding charging activities.

• Inform the home environment of the chargeable events.

Bearer Service



End-toend Service

UMTS Bearer ServiceExternal Bearer

ServiceLocal Bearer

Service

UTRAService

RadioBearer Service

IuBearer Service

PhysicalBearer Service

Backbone Phys.Bearer Service

BackboneBearer Service

CNBearer Service

Radio Access Bearer Service

TE MT UTRAN CN Iu EDGE CN gateway



Lecture 3Introduction to WCDMA

Outline



What is spread spectrum.

• Spreading.

• Correlation and RAKE receiver.

• Uplink and Downlink Diversity.

• WCDMA Power control.

– Closed loop.

– Open loop.

• WCDMA handovers.– Soft handover.

– Softer handover.

Properties of the Spread Spectrum



• Transmission bandwidth is much larger than information bandwidth.

• Bandwidth does not depend on the informational signal.• Processing gain = Transmitted bandwidth/ Information bandwidth.

• Classification:

– Direct sequence: Data is scrambled by user specific pseudo noise code at the

transmitter side.

– Frequency Hopping: The signal is spread by changing the frequency over the

transmitted time of the signal:

• Fast frequency hopping.

• Slow frequency hopping.

– Time Hopping: The data is divided into frames, that itself are divided into timeintervals. The data is burst is hopped over the frames by utilising code sequences.

Background of SS



• First publications late 40s.

– Patent proposal in 1941.

• 1949 C. Shannon and R. Pierce develop basic ideas of CDMA.• First applications 50s.

– Military with very low C/I, Anti-jam.

• RAKE receiver patent 1956.

• Cellular applications proposed late 70s.

• Investigations for cellular use 80s.

• IS-95 standard 1993.

– Commercial introduction in 1995.

• 1997/1998 3G technology choice in ETSI/ARIBA/TTA … .

TDMA based system



• Frequency reuse >1.• Frequency divided by time slots.

f1

f3

f1

f1

f2

f3

f1

f2

f3

f1

f3

f2

f2 f2

f1

f3

f2

f1

f2

f1

t

2 0 0 k

H z

WCDMA based system

f1

f1

f1



• All users share the same frequency

time domain.

• Users separated by the codes.

• Codes are orthogonal:

• FDD frequency division duplex.

– Uplink, downlink in separatefrequency bands

• TDD time division duplex.

– Uplink, downlink in the same

frequency band and separated in

time.

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1 f1

f1

f1

f1

f1f1

t

5 0 0 0 k H

z ( )1 2( ) 0

b

a

c t c t dt =∫

Processing Gain and Spreading

• A narrowband signal is spread to aid b d i l

Unspread narrowband signal

W / H

z



g pwideband signal.

• Information rate at the input of the

encoder is

• Available bandwidth is

• In order to utilize the entire available

bandwidth the phase of the modulator

is shifted pseudo randomly, according

R

W

Spread wideband signal

P o w e r d e n s i t y W

Frequency

to the pattern from the PN generator at

a rate• Chip is the rectangular pulse which occupies

the whole bandwidth

• The duration of is called chip interval• High bit rate means less processing gain and

higher transmit power or smaller coverage.

bits

s R

W Hz

times

sW

1cT

W =

cT

PNgenerator

Mod-2adder

modulator

PNgenerator

Mod-2adder

modulator

PNgenerator

Localoscillator

Adder

I

Q

Symbol

Chip

Spreading

Data



p

Despreading

SpreadingCode

Data x Code

Data

SpreadingCode

Detection own signal

Own Data

Own Spreading

Code+1

+1

-1



Despreading

Own Data x Code

Data aftermultiplication

SpreadingCode

Data afterintegration

+4

-4

+1

-1

+1

-1

-1

Despreading

Detection other signal

Other Data

Other SpreadingCode

Other Data x Code


Own Spreading

Code


+4

-4

+1

-1

+1

-1

+1

+1

-1

-1

Codes (1)• Requirements for the spreading codes:

– Good auto-correlation properties. For separating different paths.



p p p g p

– Good cross-correlation properties. For separating different channels.

Channelisation codes used for channel separation from the same source.

• Same codes from all the cells.

• Short codes: used for channel separation in Uplink and Downlink.

– Othogonality property, reduce interference.

– Different spreading factors, different symbol rates.

– Limited resource, must be managed.

– Do not have good correlation properties, need for additional long code.

Scrambling codes.

• Long Codes:

– Good correlation properties.

– Uplink: different users.– Downlink: different BS.

Long and Short Codes

Short Code+1



Short Code

Long Code

Combined Code+1

+1-1

-1

-1

The tree of orthogonal codes

• Orthogonal short codes will only be C41=(1 1 1 1)



• Orthogonal short codes will only be

useful if channel can be synchronised

in the symbol level.

– Mainly used in DL.

• Orthogonal Variable Spreading Factor

technique.

• Orthogonality preserved across the

different symbol rates.

• Codes must be allocated in RNC.• Code tree may become fragmented

code reshuffling may be needed.

• Provision of multiple code trees

within one sector by concatenation

with multiple sector specific long

codes.

C11=(1)

C21=(1,1)

C22=(1,-1)

C41=(1,1,1,1)

C43=(1,-1,1,-1)

C44=(1,-1,-1,1)

C42=(1,1,-1,-1)

SF1 SF2 SF3

Generation of a scrambling codes

• Spreading code is output of the binary shift register generator.



• Pseudo random codes are used: cyclic.

• Maximal length codes m-sequences: sequences that have maximal possible

sequence given the length of the shift registers.

• UL long scrambling code: complex scrambling codes, sum of two m-sequences (Gold sequence) generators:

– X 25+X 3+1.

– X 25+X 3+X 2+X+1.

• UL short scrambling codes.

– Used to supporting Multiuser detection.

– Sequence length around 255 chip.

• DL scrambling sequences:

– Constructed by combining two real sequences with generator polynomials:

– 1+X 7 +X 18

– 1+X 5+X 7 + X 10+X 18

clong,1,n

clong,2,n

MSB LSB

Configuration of uplink long

scrambling sequence generator

Direct sequence (DS) Spread Spectrum( )s t ( )r t ( )z t ˆ( )x t( )y t



user n information signal.

user n spreading code.

user n transmit signal.

noise.user n receive signal.

user n correlation signal.

user n output information signal.

symbol duration.

( )n x t

( )nc t

( )ns t

( )nr t ( )n t

( )nn z t

ˆ( ) x t

( ) ( ) ( )nn n n

T

z t y t c u t du= +∫ T

PSKmodulator

radiochannel

PSKdemodulator

decisioncircuit

correlatorX +

( )n

x t

( )n

c t

( )n

s t

( )n t

( )n

r t ( )nn

z t ( ) x t ( )n

y t

With ideal spreading codes and

correct timing the cross correlationbetween different users is zero

Channel Repeating

• A multipath channel:• Received signal is convolution of the received signal and the channel

( )

12

0( , )

k

M j t

k k

k h t h e

πν

λ δ λ τ

−

== −∑



• Received signal is convolution of the received signal and the channel.

• Multipath will destroy the codes orthogonality:

0 2 4 6 8 10-1

0

1

a m p l i t u d e

chips

first tap

0 2 4 6 8 10-1

0

1

a m p l i t u d e

chips

second tap

0 2 4 6 8 10-1

0

1

a m p l i t u d e

chips

third tap

0 2 4 6 8 10-1

0

1

a m p l i t u d

e

chips

received signal

– The codes are orthogonal if they aresynchronised, start at the same

moment

– If the codes are not synchronised the

cross correlation is not zero.– In multipath channel signal

components arrive at different time

moments.

– If the receiver is syncronised to a

tap. The integration covers part of the previous symbol and next

symbol from an another tap.

( )1

2

0

( ) k

L j t

n k n k

l

y t h e s t πν τ

−

=

= −∑

Maximal ratio “RAKE”

combining of symbols

Transmitted Received CombinedModified



• Channel can rotate the signal to any phase and to any amplitude.

• QPSK symbols carry information in phase.

• Energy splitted to many finger -> combining.• Maximal ratio combining corrects channel phase rotation and weights

components with channel amplitude estimate.

• Same method used also for antennae combining (BTS, MS), and softer

handover (BTS), and soft/softer handover (MS)

Transmittedsymbol

Received

symbol

Combinedsymbol

with channelestiamate

Finger #1

Finger #3

Finger #2

RAKE diversity receiver

I t i l



Correlator Phase

rotatorDelay

Equalizer

ChannelEstimator

I

Q

Input signal

(from RF)

Timing (Finger Allocation)

CodeGenerators

Matchedfilter

Combiner

Finger #1

Finger #2Finger #3

Detection own signal

Own Data

Ortogonality in multipath channel



Despreading

Own SpreadingCode

Own Data x Code

Path 1


path 1

SpreadingCode


Path 1

+4

-4

+1

-1

+1

-1

+1

+1

-1

-1

Own Data x CodePath 2

+1

-1


path 2

-4


path 2-1

+1

+4

Correlation in the receiver

1correlation of the signal

1correlation of the received signal



-8 -6 -4 -2 0 2 4 6 8-0.4

-0.2

0

0.2

0.4

0.6

0.8

Correlation functions are not delta

functions. Correlation functions of

neighbouring paths could overlap.

If the channel taps are near enough thecorrelation functions overlap and

create interference.

-2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.50

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

0 1.5 2.5

Matched filterPredefined Parallel data



• RAKE receiver needs data timing.

• When samples of incoming serial data bits are equal to bits of predefined data,

there is a maximum at filter output.

tap 127 tap 126

tap 1. . .tap 126tap 127

tap 0. . .

X

X

X

IncomingSerial data

Register 1

Register 2

Delay profile estimation

• Sum of the signals from different paths.

• Multipath propagation causes several peaks in matched filter output



• Multipath propagation causes several peaks in matched filter output.

• Allocate RAKE fingers to these peaks.

• Later: track and monitor the peaks.

( ) ( ),l j

k l k k l

L

P e m s t n t τ − Θ − +∑( )( ) ( )

( )( )

( ) ( )

,

1

0

,

, , 1 ,

, ,0 ,

( )

( )

n l

l

l

n l

u

j

k l k k k l k

T

k T L j

k l k k k l k

u

k

T

P e m s t u s t dt

z t

P e m s t u s t dt

n t s t dt

−

− Θ−

− Θ

−

= + −

+

∫ ∑

∫ ∫

Signal in the channel Signal after correlation in receiver

The correlation generates multipath

interference from other paths.

Performance of a DS-CDMA receiver

Signal in the channel in a channel with multiple users:

Signal sample at the receiver:

( ) ( ),n l n n

N L

P m s t n t +

∑∑T



( ) ( )( ) ( ) ( )( )

( )( ) ( ) ( )( )

( ) ( )

, 0

, ,

1 ,

, 0

, ,

1 ,

, , 1 , , ,0 ,

, , 1 , , ,0 ,

( )

( )

n l

k l k l

n l

n l

n l n l

n l

u T

j j

k l k k k l k k l k k k l k

L T u

u T j j

n l n n n l k n l n n n l k

N L T un k

k

T

z t P e m s t u s t dt P e m s t u s t dt

P e m s t u s t dt P e m s t u s t dt

n t s t dt

−

−

− Θ − Θ−

− Θ − Θ−

≠

= − + −

+ − + −

+

∑ ∫ ∫

∑ ∑ ∫ ∫

∫ is the received power of the signal for user

n.

is the transmitted symbol to user n.

is the spreading code of user n.

is the random noise after the carrier

demodulator.

Delay of the user n path compared to the

user k path.

,n lP

nm

( )n

s t

( )n t

• The first term on the right side represents

the desired signal sample of the k th user.

• The second term represents the multiple

access interference (MAI) and can be

modelled as Gaussian.

• The third term represents the random

noise.

• Index k is used to select the parts from

the equation with the user signal.

,n lu

• Receiver performance in a Gaussian channel is fully characterised by the firstand second moment of the received signal:

Performance of a DS-CDMA receiver (2)

E P Q



Example.

• Assume:– Single symbol transmission with single symbol transmission.

– Only one multipath component for each user ( L=1 ) and a real channel.

– Single cell network.

• The received signal can be simplified.

• Variance of the interference is:

2beP Qσ

=

( )

( )

{ } ( ) ( )

2

2

,

0 0

2

0 0 0

( )

( )

MAI n i n k i

N n k

N N

i j i j ik i jk j

i ji k j k

N N N

i j i j ik i jk j i ik i

i j ii k j k i k

E P m R u

E PP m m R u R u

PP E m m R u R u PR u

σ

≠

= =≠ ≠

= = =≠ ≠ ≠

=

=

= =

∑

∑∑

∑∑ ∑

{ }

2

0

0 0

0

20 0

( ) ( )

( ) ( ) ( ) ( )

( ) ( ) ( )2

( ) (0)2 2

n k

T

k k

T T

k k

T T

k kk

T

E n t s t

E n t n u s t s u dtdu

N t u s t s u dtdu

N N s t dt R

σ

δ

=

=

= −

= =

∫

∫ ∫ ∫ ∫

∫

By using definition of the autocorrelation:

Performance of a DS-CDMA receiver (3)

( ) (0) ( ) ( )k k kk n n nk

N

z t P m R P m R u n T = + +∑



N n k ≠

is the code autocorrelation function of user k.

is the codes crosscorrelation function between spreading codes of user n and

user k .

is the cross correlation function between the random noise and the spreading

code of user k .

(0)kk R

( )nk R u

( )n T

The performance of the receiver is expressed in terms of the Q function:

0

2

2

2

(0)

( ) (0)

k kk be N

n nk n kk

N n k

P R E P Q Q

I P R u Rη

≠

= = + + ∑

In the asynchronous case when the delay u is uniformly distributed over thesymbol interval, the expected value of the correlation function ratio is about:

2

2

( ) 1

(0) 3

nk n

kk c

R u E

R G

≈

where c

c

s

R chip rateG N processing gain

R symbol rate= = = =

Performance of a DS-CDMA receiver (4)The average bit error probability can be calculated as a function of number of users:

Assume:2 ( )

k k P P E

RR uI η= ≈

+ k nP P=



00

222

( )(0)

3(0)

N s N nk nn sn kk

N N kk n k n k

R R u I P RP R

W R

η

≠≠

+ ++ ∑∑

If the target SIR ratio given we can estimate the average capacity in the cell.

Assumptions made:

• Powers have the same level:

– Near far effect.

– power control suitable for uplink.• No intracell interference:

– can be considered by the intracell interference factor.

– Other cells change the transmission power in the same way than the users cell.

• Orthogonality:

– In downlink all the codes from one BS synchronous - codes orthogonal - no

interference.

– Multipath channel ruins orthogonality.

– Can be considered in downlink as orthogonality factor.

CDMA capacity an another approach

• Same assumptions as before. We attempt directly evaluate the equation E

I η+



0

I Total interference I the noise density in demodulator =

W entire spread bandwidth= =

The total interference power is: where N is number of users.

Total number of users in the system is:

Compared to analyse in previous slides we assume here that Coding Gain (G) is equal

to . Before we assumed it to be . In practice both of these values are only

assumptions and the real coding gain depends on the particular codes and multipathdelays in the system.

=nb

n

P received signal power E received energy per bit

R data rate= =

I η +

( )1 n I N P= −

0

1n b

I W R N P E I

− = =

n

W

R

3

n

W

R

Capacity in multicell environment

Problems:

• We assume that all the powers are the same (suitable only for uplink).

• No other cell interference:



• No other cell interference:

Other cell interference can be considered by the interference factor f . Assume that

other cells generate that is added to the own cell interference. Thus capacity in the

whole system is reduced.

The new capacity is:

• Codes that are synchronised are orthogonal:

– In downlink all the signals are emitted from the same source and propagate along

the same path. The spreading codes that are synchronised are orthogonal.

– Can be considered by the orthogonality factor . That is a term that describes how

much the interference is reduced due to the codes orthogonality.

1 1interference from other cell f interference from own cell+ = +

0

1 11

1 1n b

I W R N

P f E I f − = =

+ +

α

(1 )

k

n

N n k

PW W SIR CIR

R R Pα η

≠

= =− +∑

Simple equation describing quality of

CDMA system

where0,0PCIR



where

signal power for user k in cell I

noise power

0

,

11

,0 ,

1 1 1

jK K N

k k j

k j k

CIR

P P η −−

= = =

=+ +∑ ∑ ∑ ,k iP

η

0 ,0

0

1,0

0

,00

1

1,0 ,0 ,

1 1

1

0 ,0 ,0 ,

1 1

1

0 ,0 1,0 ,

1 1

... 0

... 0

... 0

j

j

j

K

K N P

K k jCI R

j k

K N

PK k jCI R

j k

K N P

k jCI R

j k

P P P

P P P

P P P

η

η

η

−

= =

−

= =

−

= =

− + + + + + =

− + + + + =

+ + − + + =

∑ ∑

∑ ∑

∑ ∑

Equations for all users

Near far effect

Uplink: Because of different attenuation signals to/from users nearer to BS are

stronger than signals to/from further located users.



g g

Radio tower

R e c ei v e d p ow er a t B S

MS1

MS

2

M

S3

Without Power Control

R e c ei v e d p ow er a t B S

MS

1

MS

2

MS

3

With Power Control

Downlink: Beacause of the nature of attenuation at the cell border the users

experience higher interference that near to the BS. They have high level of

interfering signals from own BS and from other BS.

• Removes near far effect.• Mitigates fading.

Amplitude

Time

Purpose of Power Control in WCDMA



• Uplink

Power control in uplink must make signal powers from different users nearlyequal in order to maximise the total capacity in the cell.

• Downlink

In downlink the power control must keep the signal at minimal required level in

order to decrease the interference to users in other cells.

• Compensates changes in propagation conditions.

• In the system level

– decrease interference from other users– increase capacity of the system

Time

Power Control types in WCDMA

• Open Loop power control: for initial power setting of MS

Transmitter



Across the air interface

• Fast closed loop power control:

– Mitigates fast fading rate 1.5 kbps.

– On UL and DL.

– Uses a fixed quality target set in MS/BS.

• Outer loop power control:

– Compensates changes in environment.– Adjust the SIR target to achieve the required FER/BER/BLER.

– Depends on: MS speed available, multipath diversity.

– In the soft handover comes after frame selection.

Modulation

Demodulation

Channeldecoder

ChannelEncoder

SourceEncoder

SourceDecoder

Channel

Multiple accessinterference

NoiseReceiver

Powercontrol

C/I target

FER BER C/I

Open Loop PC

What is initial transmission power?



The BS transmits in BCCH• power of the PRACH.

• power step P.

- MS sets the initial transmission power Ptr

in RACH/CPCH and waits for ack.- if no ack during TCPCH

Ptr(i+1) = Ptr(i) + P

BCCH RACH/CPCH

Closed Loop Fast PC

• Uses channel in other direction for transmitting the order for power change.

coder decodermodulator demodulatorchannel



• Applied only to dedicated channels.

• Makes Eb/No requirements lower.

• Introduces peaks into the transmit power.

• PC speed 0.666 ms, compensates the fading for slow and medium speed.

• PC step

– uplink 1, 2, 3 dB

– downlink 0.5, 1 dB

• Control range– uplink 80 dB

– downlink 30 dB

decoder coderchannel modulatordemodulator

Fast PC

Uplink:

Behaviour precisely standardised.Downlink:

Precise algorithm not standardised



p y

• Equalizes received powers at BS

• BS measures the received CIR

and compares to the target CIR

value

• BS transmits the TPC command

in downlink and orders the MS to

increase/decrease thetransmission power

• MS change the transmitted power

accordingly to the TPC command

Precise algorithm not standardised

• MS estimates the received SIR and

compares it with required SIR target

• MS transmits the TPC command in first

available TPC field

• In soft handover (diversity transmission)

– two downlink PC modes

• MS sends unique PC command in eachslot

• MS repeats the same PC command over

3 slots

• Changes of power are multiplies of the

minimum step size– it is mandatory for BS to support 0.5 and

1 dB step size

Outer loop PC• Used for long term quality control

• Controls of the channel by setting target Eb/No– the quality requirement is given as long term average of FER/BER

• Uplink



• Uplink

– SRNC sets the target value

– Control is located in the Node B for FDD– for TDD function is performed by UTRAN but target quality value is sent to the

MS

• Downlink

– located in UE, the initial control parameters are set by UTRAN

– receives inputs of the quality estimates of the transport channel

FER and FEP are calculated upon number of frames

Example function for outer loop PC EbNoTarget (t +1) = EbNoTarget (t) + [dB]

where = fs-Fs

f is 1 if frame has error accordingly CRC and 0 if not

F is the wanted FER

s is the step size.

Effectiveness of PC (1)

• The figure of fading from the file.



• Uplink:

– In uplink an effective power control follows fading as good as possible.

– In the “own” BS received powers are equal. In other BS high variations.

• Downlink:

– The power control attempts to estimate the overall interference level in the

cell (system).

– The PC attempts to provide good CIR to the as many users as possible.

WCDMA handover types.

• Intra-system handovers:– Intra-frequency handovers.

• MS handover within one cell between different sectors: softer



• MS handover between different BS:

– Soft.

– Hard.

– Inter-frequency handovers.

• Hard

• Inter-system handovers:

– Handover between WCDMA <--> GSM900/1800: Hard

– Handower between WCDMA/FDD <--> TDD: Hard

WCDMA handovers



• Avoidance of near far situation for circuit switched connections

– for high mobility users shadow fading + (slow) hard handovers would create near

far situations.

• Soft/Softer handovers will improve cell capacity (around 40-60 %)

• Soft/Softer provide macrodiversity gain: compared the hard handover larger

cell range.

– Gain against shadow fading ( 1 -3 dB).– Gains against fast fading, typically 0.5 - 2 dB assumed.

• Soft/Softer essential interference mitigating tool.

Softer handover

• MS in overlapping cell coverage area of

two adjacent sectors of a BS



two adjacent sectors of a BS.

• Communication between MS and BS is

via two air interface channels (one foreach separate sector).

• Different sectors have different

scrambling codes.

• UL: MS tunes the RAKE fingers to

different sectors and combines the

outputs.

• DL: BS receives signals with different

antennas and decodes and combines

them.

Radio tower

Soft handover

• User has at the same time connection to more than one BS.

• Except PC bits exactly the same information is sent via air interface.

• Soft handover probability 20-40 %.

• UL/DL processing different



• UL/DL processing different.

– MS: At Rake Maximal Ratio Combining of signals from different BS.

– BS: Frame selection. Extra transmission across Iub.

Radio tower

Radio tower

RNC

CN F r a m e

r e l i a b

i l i t y i n f

o

F r a m e r e l i a b i l i t y i n f o

Handover impact to capacityAttenuation in the channels

P[db]

Handoffwindow



P[db]

increase oftransmitted power

P[db]

C el l s ite 2C el l s ite 1 Ce l l

boundary

Transmitted power in UL

Transmitted power in DL

Handover procedure

• Strength of the A becomes equal to

defined lower threshold. The

neighbouring signal has adequate

strength B is added to active setn a l S t r e n g t h

Summed Signal

Handover margin



strength. B is added to active set.

• Quality of signal B starts to become

better than signal A. The RNC keepsthat point as starting point for

handover margin calculation.

• The strength of signal B becomes

equal or better than the defined lower

threshold. Thus its strength isadequate to satisfy the required QoS

of the connection. The strength of the

summed signal exceeds the

predefined upper threshold, causing

additional interference to the system.

As a result, RNC deletes signal A

from the Active Set.

Time

S i g n

Signal A Signal B

Radio tower Radio tower

Cell ACell B

Parameter in the handover algorithm

• Upper threshold: the level at which the signal strength of the connection is at

the maximum acceptable level in respect with the requested QoS.

• Lower threshold: is the level at which the signal strength of the connection is



• Lower threshold: is the level at which the signal strength of the connection is

at the minimum acceptable level to satisfied the required QoS. Thus the signal

strength of the connection should not fall below it.• Handover margin: is a predefined parameter, which is set at the point where

the signal strength of the neighbouring cell (B) has started to exceed the signal

strength of current cell (A) by a certain amount and/or for a certain time.

• Active Set: is a set of signal branches (Cells) through which the MS has

simultaneously connection to the UTRAN.

• Candidate Set: is a list of cells that are not presently used in the soft handover

connection, but whose pilot E/I are strong enough to be added to the active set.

– Candidate set is not used in WCDMA handover algorithm.

• Neighbour Set: The neighbour set or monitored set is the list of cells that themobile station continuously measures, but whose pilot E/I are not stron enough

to be added to the active set.

User Traffic Modeling for Future Mobile Systems

• The goal was to gain new knowledge and develop expertise about the finestructure functionality of packet data traffic for the development of future mobiledata systems.

T t d l hi h d t l d ib th h t i ti f th



• To create a model, which adequately describes the characteristics of theindividual user’s connection over different time scales.

• A special interest in the lower levels of the time scale• Packet data traffic measurements for

- WWW service in laboratory LAN 1996 and 1999 and WLAN 1997.- WAP over GSM data and over GPRS from a test WAP-gateway 2000-2002

• The data was grouped by individual connections and analyzed based on the

protocols used.• The statistics were modeled based on events of WWW session

- Developed from the ETSI packet data model (referred Ch. 10.1)- measured distributions are fitted to some analytic distributions- aim is to get parameters for simulation model(s)- intended to developing radio link protocols and radio network planning

Wired vs. Mobile Data Traffic

• In fixed networks- bandwidth is large and rapidly growing and transmission errors are rare- most crucial elements are the centralized components like main trunks, routers

or servers



- one of the main problems is the aggregate traffic of numerous users, whichoverloads these relatively few "bottlenecks"

=> the traffic should be measured from the "hot spots".

• In mobile networks- Bandwidth is quite limited and the probability of transmission errors is rather

high- Few active users can make use of most of the traffic capacity available in a

cell- The main "bottleneck" is the air interface at the edge of network

=> the traffic should be measured as close to the client as possible.

• In WCDMA BER/FER performance is optimized based on average E b /N 0

- The average E b /N 0 is not accurate if high bit rate packet users cause rapidchanges in interference.

WWW traffic

• One of the most spread services in the Internet

• Often used as user interface for new services

• HTTP protocol

• Uses TCP and IP protocols for transmission



• The technology develops on various levels => has impact on the results

- Internet bandwidth is increasing- Processing power of both clients and servers is increasing- New software versions offer more capabilities

• Changes in the user behavior and the contents of Internet

- Amount of data in Internet is increasing- People use WEB more frequently- Number of items per page is increasing

• Physical distances remain => Round trip time (RTT)

The UMTS-network

• aimed to cover almost all the data transmission needs of the users• different delay and other quality demands

• the behavior of most significant services present in the network is needed to- follow the effects of changes loading



follow the effects of changes loading- evaluate the functionality of the network

- evaluate the service quality (see lect. 1 p. 32-36)- control them (for example the usage of priorities)

WAP traffic

• to provide a mobile user a WWW like access to the Internet.

• a HTTP-like protocol optimized to the wireless domain.

• Uses TCP and IP protocols for transmission

• The measurements used circuit switched GSM data and WAP protocol 1.0.• The traffic logged simultaneously from both sides of the gateway.

• The effects of wireless and Internet connection and the gateway separated

• already the activity during WAP-transaction < voice activity (esp. uplink)



Packet data traffic measurements

• Data packets were collected by TCPDUMP• analyzed by C and MATLAB programs.

• The data was grouped and analyzed based by- Users (or PC) indicated by IP- and MAC-addresses



( ) y- Services indicated by ports used by TCP/UDP-protocols.

• Packet level statistics 42 figures- size of every IP- and data packet both directions- delays between packets in both directions- comparisons of delay distributions

- delays between packets on the same WAP-item- number of WWW-items/page and -pages/session

• Bursts, Nibbles, WAP-items, -connections, -pages and WAP-sessions, 24 figureseach- size of groups in packets and in bytes

- delay from previous group- length of the group- cumulative distributions- distributions of bytes based on length of group

The used definitions

Packet IP-packet

Nibble Smallest burst of data, which UMTS would distinguish.group separated with idle > 10 ms.

B t ti t i i t d ith idl 2



Burst active transmission, group separated with idle > 2 s.

TCP/ WSP- A numbered connection/transaction between WWW-connection server and -client or WAP-gateway and -client.

One TCP-connection can carry tens of WWW-items.

WWW/WAP- A request/response pair transferring NEW payload data text,item picture etc., on same TCP/WSP-connection

WWW/WAP- WAP-items that forms one visual display unit. Separatedpage by a reading period, defined from 1 to 300 seconds.

WWW/WAP- A period when client is active. Separated by inactivity of nosession WWW/WAP-page during 5 minutes (= reading time > 5 min.)

Creating the model

• Modeling is done by fitting the cdf of the result to analytic distributions / theirmixtures.

• To maintain the information over different time scales, the fitting is done usinglogarithmic x-axis



• A discrete vector of size 221 samples covers the time scale from 10-6 (1 µs) to

105

(1,25 days) with a resolution of 20 points/decade.

• The model is fitted to the measured distribution by numerical iterations.

• The correctness of fitting is evaluated visually

• The distributions used are exponential, Pareto and for small discrete values also

geometric.

• the distributions have been enhanced to fit better to the measured data

• no zero length delays => shift (= fixed delay) added to exponential distribution

• bias (= fixed value of zero)

The Pareto distribution

• is defined by

1( ) , x

k f x x k

α

α

α

+

⋅= ≥ (0.1)



1x xα + (0.1)

0 ,( )1 ( ) ,

xk xF x

k k x x

α <=

− ≤(0.2)

, 11

k α µ α

α = ≥

− (0.3)

22 , 2( 2) ( 1)

k α σ α

α α ⋅= >

− ⋅ − (0.4)

• when α < 2 the variance and when α < 1 also the mean become infinite

• normally the Pareto distribution is limited to area 1 < α < 2

Truncating the Pareto distribution

• parameter T added to compress the in principle unlimited Pareto distribution tothe practice

0 ,k x<



1 ( )( ) ,

1 ( )

1 ,

x

k

xF x k x T k

T

x T

α

α

−

= ≤ ≤−

>

(0.5)

• closes unlimited Pareto, when T/k and α increase

• if k = 10-3 , the difference in cdf between T = 103 and T = 10333 (~ infinity ) is

- only 10-9, when α = 1.5

- but 10-3, when α = 0.5

• in many cases small values of α (min = 10-5) give a pretty good fit to measured

data. Then the graph becomes a slope line in semi logarithmic domain.

Geometric CDF

• directly from Matlab defined as

( )

( ) 1 floor x

iF x p pq where q p= = −∑ (0 6)



0i=∑ (0.6)

• Since the mathematical distribution starts from zero to reach the aimed mean Pmust be set

1

1P

mean=

+ (0.7)

The developed traffic data models

• The selected statistics were fitted to analytic distributions• simple model is one CDF and partial model is weighted sum of one exponentialand two truncated Pareto CDFs

• models are a collection of several measurable distributions on different levels intop down order



top-down order

• the mean and variance for the measured data and the models• error value used as the measure in curve fitting

WWW-traffic data model

• model is a collection of eleven measurable distributions on three levels asdescribed in figure 3 in top-down order:

1. The WWW-session interarrival time D www 2. The number of packet calls (pages) per WWW-session N pc

3. The reading time between packet calls (WWW-pages) D pc 4. The number of items per WWW-page N i .5. The time intervals between items belonging the same WWW-page D pii

6. The number and size of packets belonging to an WWW-item are conductedabout the information about the TCP-protocols mechanisms and their influencesand the distributions of

6.1. WWW-item sizes on Uplink S iu 6.2. WWW-item sizes on Downlink S id

7. The time intervals between packets belonging the same WWW-item are dividedin four subcategories to adapt to the different delay behavior depending on the



g p y p gdirection of transmission

7.1. the time int. between two consecutive Uplink packets inside an item D iuu 7.2. the time interval from Uplink to Downlink packet inside an item D iud 7.3. the time int. between two cons. Downlink packets inside an item D idd 7.4. the time interval from Downlink to Uplink packet inside an item D idu

To make comparison easier each distribution for both models are presented in atable for both 1996 and 1999 measurements. In a third table there is a comparisonof the mean and variance for the measured data and the both models. There isalso the error value, which was used as the measure in numerical curve fitting andoptimization. It is the sum of squared error between the CDF vectors for measured

data and the model.

A sample distribution for D www

4.1 The WWW-session interarrival time, D www

D www 1996 1999

Distribution % Parameters % ParametersTruncated k=Pareto α=

T=

100 346.70.3675

3.32e+06

100 260.520.4195

3.8236e+33

s

s

Table 4 1 The simple model for WWW session interarrival time D



Table 4.1 The simple model for WWW-session interarrival time D www

D www 1996 1999Distribution % Parameters % Parameters

Exponential µ=start is shifted

3.18 3136.60.001

16.14 254.90301.51

ss

Truncated k=

Pareto α= T=

70.46 295.90.3842

1.012e+20

74.53 257.930.3766

1.155e+19

s

s

Truncated k=Pareto α=

T=

26.36 643.510.4624

7.103e+16

9.33 1498.90.212973509

s

s

Table 4.2 The partial model for WWW-session interarrival time D www

D www 1996 1999

Distribution Measured Simple Accurate Measured Simple Accurate

Mean 16877.9 16639.4 16791.9 13358.3 14005.4 14005.0Variance 31053.0 30805.4 31346.9 26959.0 29103.0 28691.1Error 0.010323 0.004739 0.011458 0.004435

Table 4.3 The mean, variance and modeling error for WWW-session interarrival time Dwww

WAP-traffic data model

• model is a collection of twelve measurable distributions on three levels as

described in figure 3 in top-down order:

1. The WAP-session interarrival time D wap

2. The number of packet calls (pages) per WWW-session N pc

3 The reading time between packet calls (WAP items) D



3. The reading time between packet calls (WAP-items) D pc

4. The number and size of packets belonging to an WAP-item are conducted aboutthe information about the TCP-protocols mechanisms and their influences andthe distributions of- WAP-item sizes on Uplink S iu

- WAP-item sizes on Downlink S id

5. The timing during a WAP-item is divided in five (WDP) or seven (WTP) parts tocorrespond to the model presented in figure 2- the transmission time of the Uplink packet (WAP-request, begin an item) D wu

- the processing time of WAP-request D pu

- the WWW-transaction waiting time D www

- the processing time of WAP-response D pd

- the transmission time of the Downlink packet (WAP-response) D wd

- the acknowledgement times on Uplink D au and Downlink D ad

• Presently there are distributions for the WAP-item size and WAP-transactionsinternal timings

• With D wap , N pc and D pc the problem is that IP address often changes duringWAP-sessions, when GSM-data connection disconnects for idle periods. Afterthat there in no information about the original user.

• a “browser-session” does not model users on the higher levels



• a browser session does not model users on the higher levels.

• 122 550 WAP/WWW-items are distributed to 11697 “browser-sessions” of which~ 10 % do overlap and only ~60 % are separated by over 5 minute period.



Figure 2. The model of WAP transaction timing. Figure 3. The model of WWW-session timing.



• Figure 1.0 depicts a typical WWW browsing session, which consists of asequence of packet calls.

• We only consider the packets from a source, which may be at either end of thelink but not simultaneously.

• The user initiates a packet call when requesting an information entity.

• During a packet call several packets may be generated, which means that thek t ll tit t f b t f k t



packet call constitutes of a bursty sequence of packets.

• It is very important to take this phenomenon into account in the traffic model.• The burstyness during the packet call is a characteristic feature of packet

transmission in the fixed network.

• A packet service session contains one or several packet calls depending on theapplication. For example in a WWW browsing session a packet call corresponds

the downloading of a WWW document.• After the document is entirely arrived to the terminal, the user is consuming

certain amount of time for studying the information. This time interval is calledreading time.

• It is also possible that the session contains only one packet call. In fact this is thecase for a file transfer (FTP). Hence, the following must be modeled in order tocatch the typical behavior described in Figure 1.0:

• Session arrival process Modeled as a Poisson process. Has nothing to do with call termination .

• Number of packet calls per session, N pc N Geom pc Npc∈ ( ) µ .

• Reading time between packet calls, D pc D Geom pc Dpc∈ ( ) µ

• Number of datagrams within a packet call, N d N Geomd Nd ∈ ( ) µ .• Inter arrival time between datagrams (within a packet call) D d D Geomd Dd ∈ ( ) µ .

• Size of a datagram, S d Pareto distribution is usedThe session length is modeled implicitly by the number of events during the session.



Table 1.1 Characteristics of connection-less information types (default mean values for the distributions of typicalwww service)

Packet based

information types

Average number

of packet calls

within a session

Average reading

time between

packet calls [s]

Average amount of

packets within a

packet call []

Average

interarrival

time between

packets [s]1

Parameters for

packet size

distribution

WWW surfingUDD 8 kbit/sUDD 32 kbit/sUDD 64 kbit/sUDD 144 kbit/sUDD 384 kbit/sUDD 2048 kbit/s(originallyUDD 8 kbit/s)

5

5

5

5

5

5

5

412

412

412

412

412

412

12

25

25

25

25

25

25

15

0.5

0.125

0.0625

0.0277

0.0104

0.00195

0.96

k = 81.5

α = 1.1

1 The different interarrival times correspond to average bit rates of 8, 32, 64, 144, 384 and 2048 kbit/s.

According to the values for α and k in the Pareto distribution, the average packet size µ n is 480 and average requested file-

size is µ Nd

x µ = 25 x 480 bytes ≈ 12 kBytes. The packet size is limited to 66 666 bytes, giving a finite variance to the distri-

bution. (First the truncations effect were neglected giving µ n = 896 bytes and µ

Nd x µ = 15 x 896 bytes ≈ 13,4 kBytes.)

• The principle of dividing the model to layers like session, packet call and apacket is very good and describes the quite closely the actual process

• major drawback in the presented model are:

1 it does not take in to the consideration the direction of the packets



1. it does not take in to the consideration the direction of the packets

- measured WWW traffic has great asymmetry- delays are different for example up to Down (~RTT) and down to up- used protocols can differ between Uplink and Downlink

2. WWW-pages are often composed of several (on average 4.8) WWW-items which usemore than one parallel TCP-connections.

3. the systematic usage of selected statistic distributions can mask out some typicalfeatures.- For example the datagram (=packet) size and average interarrival time distributions.

The timing diagram presented in the figure 2. WAP transaction is there divided infollowing parts:

1. WAP-request transmitting time T0A/T2A. Calculated by dividing the packet sizeby line speed 9,6 kbit/s

2. WAP-request processing time in Gateway T0B/T2B



3. WWW-transaction waiting time T0C/T2C

4. WAP-response processing time T0D/T2D

5. WAP-response transmitting time T0E/T2E. Calculated by dividing the packet sizeby line speed 9,6 kbit/s.

6. WAP-response acknowledgement time T2F (only in WTP). The time used by tothe Mobile terminal to (process and) accept the WAP-response. The minimum =26 ms. The measured from 32 ms to 12,6 s (mean 778 ms).

WSP/WDP(WAP0)

WAP1 ( =WAP2+rep)

WSP/WTP(WAP2)

WWW(WAP3)

Packets up 35 726 245 350 238 948 1 001 830

Packets down 35 831 297 241 242 609 940 535

Data-Packets up 35 726 123 288 122 550 137 550Data-Packets down 35 831 175 996 121 366 321 312

IP-bytes up [kB] 4 838 14 777 14 508 95 673

IP-bytes down [kB] 17 287 66 681 56 262 153 376

Data-bytes up [kB] 3 802 7 044 6 974 55 035

D t b t d [kB] 16 248 57 466 48 740 179 741



Data-bytes down [kB] 16 248 57 466 48 740 179 741

Mean Item size up 136 136 136 136Mean Item size down 479 479 479 479

Bursts 27 901 137 064 97 435 392 309

WAP/WWW-items 35 604 122 550 122 550 136 999

WSP/TCP-connections 35 604 122 651 122 651 138 299

WAP/WWW -pages 28 882 85 243 89 492 122 500

WAP/WWW-sessions 3 028 11 722 11 723 7 467Burst time [s] 15 178 171 667 160 526 127 716

Item time [s] 52 856 404 943 128 039 78 789

TCP-connection time [s] 52 856 541 389 270 440 75 731 900

Page time [s] 46 614 491 371 269 959 77 703

Session time [s] 491 546 1 901 940 1 708 820 2 369 690

Table 1. The main statistics of data measured Packets, IP-bytes and Data-bytes, the mean sizes of WAP&WWW-Items, the numbers and total lengths of Bursts, Nibbles, WSP-connections, WAP&WWW- items, -pages and -sessions .

Measures for averageTimes

Means Medians Mean formodels

WSP/WDP ms % ms % ms %

WAP-request transmitting 113,36 6,9 112,00 20,0 113,30 10,9WAP-request processing 24,80 1,5 2,00 0,4 6,07 0,6

WWW-transaction 541,59 32,8 79,40 14,2 453,72 43,6

WAP-response processing 591,33 35,8 50,10 9,0 73,62 7,1

WAP-response transmitting 381,38 23,1 316,00 56,5 393,74 37,8

Total 1652 46 100 559 50 100 1040 44 100



Total 1652,46 100 559,50 100 1040,44 100

WSP/WTP ms % ms % ms %WAP-request transmitting 75,23 6,7 63,10 10,1 75,81 5,6

WAP-request processing 22,37 2,0 2,51 0,4 19,24 1,4

WWW-transaction 469,48 41,8 141,00 22,6 451,04 33,4

WAP-response processing 101,94 9,1 20,00 3,2 352,89 26,1

WAP-response transmitting 454,17 40,4 398,00 63,7 452,98 33,5

[Acknowledgement frommobile]

777,72 69,2 708,00 113,4 764,21 56,5

Total 1123,19 100 624,61 100 1351,95 100

Table 2. The average times for different parts of WAP-transaction.

Measures for average Times Means Medians Mean formodels

WSP/WDP s s s

WAP-Transaction duration 1,979 0,636

WAP-Page duration 2,109 0,695WAP-session duration 162,828 71,295

WAP-Transaction separation 881 5,815

WAP-Page separation 1087 9,505

WAP-session separation 10223 1119,505

WSP/WTP s s s



WSP/WTP s s s

WAP-Transaction duration 2,280 1,335WAP-Page duration 3,092 1,855

WAP-session duration 145,842 70,875

WAP-Transaction separation 254 7,865

WAP-Page separation 348 14,025

WAP-session separation 2537 446,925

Table 3. The average times for duration and separation for WAP-transactions, WAP-pages and WAP-sessions.

The activity during WAP-transactions and -sessions

The activity we defined as the minimum time needed to transfer the measured IP-packets over the given

bandwidth

Activity duringTransactions

By mean By median By model

WDP-Transaction up 113,36 6,9 112,00 20,0 113,30 10,9

WDP-Transaction down 381,38 23,1 316,00 56,5 393,74 37,8



WDP Transaction down 381,38 23,1 316,00 56,5 393,74 37,8

WDP-Transaction duration 1652,46 559,50 1040,44WTP-Transaction up 75,23 4,0 63,10 4,7 75,81 3,6

WTP-Transaction down 454,17 23,9 398,00 29,9 452,98 21,4

WTP-Transaction duration 1900,91 1332,61 2116,17

Table 4. The Activity during WAP-transactions.

Activity during sessions By mean By median By modelWDP-Transaction duration 1,98 1,2 0,64 0,9

WDP-Transaction number 10,76 10,76 10,76

WDP-Transactions total 21,29 13,1 6,84 9,6

WDP-session duration 162,83 71,29

WTP-Transaction duration 2,28 1,6 1,34 1,9

WTP-Transaction number 9,46 9,46 9,46WTP-Transactions total 21,58 14,8 12,63 17,8

WTP-session duration 145,84 70,88

Table 5. The Activity of WAP-transactions during WAP-sessions .

• The user activity during WAP-sessions will be a result from multiplication of- the activity factor inside WAP-transactions (Table 4) and- the part WAP-transactions take during the WAP-sessions (table 5).

- WSP/WDP uses uplink 7- 20 % and WTP/WSP only 4-5 %.- WSP/WDP uses downlink 23- 57 % and WTP/WSP only 21-30 %.- The ratios between uplink and downlink are 1: 2,8-3,5 for WDP and about 1: 6

for WTP.- The relations between IP bytes transferred are 1: 3,6 for WDP and 1: 3,9 for



y , ,

WSP (incl. opening and closing).

• In matched transactions the WAP has compressed the data on average to 20 -43 % compared to WWW

• The total relation of transferred bytes is 37 % with 92,9 Mb of WAP (WDP and

WTP together) and 249 MB of WWW traffic.• If an end-to-end WWW would be used the wireless link activity would increase168 % and the times in table 2 would increase 0,9 - 1,2 seconds

• The WWW-items created by WAP are smaller and time intervals betweenWWW-packets are mostly larger than with normal WWW-items. Most requestand responses fit to a single packet.

• Keep-alive packets should be excluded from all the statistics of WWW-items,pages and sessions.



Radio Access Network Architecture

Jussi Tuominen

3GPP Release 99 Reference Architecture

RNC

Node B

SMSC

/VLR GMSC

SS7 SS7

Iu-

CS



Node B

RNC

IubUu

UENode B

Node B IubUuIur

SGSN

/VLR

GGSN

HLR EIR Auc

Iu-

PS

Gn Gi

UTRAN Core Network

Jussi Tuominen 30.1.2002

UMTS Terrestial Radio Access Network

(UTRAN)

WCDMA Radio Interface Key Change from GSM



UTRAN elements are comparable to GSM BSC & BTS

Common Interface (Iu) for both PS and CS Core

Core elements do not change dramatically

- 3G SMSC/VLR provides ATM based Iu-CS interface

- 3G SGSN supports ATM based Iu-PS interface


UTRAN Architecture

Hierarchical Architecture

• Radio Network Subsystem

(RNS)

• UTRAN Elements:

Node B

Node B

RNC



– Radio Network Controller

– Node B (Base Station)

• One RNC controls number of

Node B’s

• Node B is only connected to

one RNC

• New interface Iur forMacrodiversity

Node B

Node B

RNC

Uu

Uu Iub

Iub

Iu-

PS

Iu-

CSIur

UTRAN

RNS


RNC

Node B

Macro Diversity

Iu

Softer Handover



Node B

RNC

IubUu

Node B

Node B IubUuIur


RNS

UTRAN

•1 BS

•1 RNCUE

RNC

Node B

Macro Diversity

Iu

Soft Handover



Node B

RNC

IubUu

Node B

Node B IubUuIur


RNS

UTRAN

• Number of BSs

•1 RNC (MDC)UE

SRNC

Node B

Macro Diversity

Iu

Soft Handover



Node B

DRNC

IubUu

Node B

Node B IubUuIur


RNS

UTRAN

• Number of BSs

• 1 Serving RNC (MDC)

• Number of Drift RNC

UE

SRNC

Node B

Macro Diversity

Iu

SRNC Anchoring



Node B

DRNC

IubUu

Node B

Node B IubUuIur


RNS

UTRAN

UE Iu

RNC

Node B

Macro Diversity

Iu

SRNC Relocation



Node B

SRNC

IubUu

Node B

Node B IubUuIur


RNS

UTRAN

UE Iu

Node B

• Standardisation term (normally called as Base Station)

• Comparable to Base Tranceiver Station in GSM

• Responsible for Air Interface Layer 1

• Key Node B Functions:



• Modulation and spreading

• RF Processing

• Inner-loop power control

• Rate matching

• Macro diversity combining/splitting inside Node B


Radio Network Controller (RNC)

• Comparable to Base Station Controller in GSM• Responsible for L2 processing of user data

• Responsible for Radio Resource Management

K RNC F i



• Key RNC Functions:• Closed loop power control

• Handover control

• Admission control

• Code allocation

• Packet scheduling

• Macro diversity combining/splitting over number of Node Bs


General Protocol model for UTRAN

ApplicationProtocol

DataStream(s)

T t T t N t k

Control Plane User Plane

T t N t kT t N t k

Radio

NetworkLayer




Lähde: 3GPP TS25401-380

ALCAP(s)

TransportNetwork

Layer

Physical Layer

SignallingBearer(s)

TransportUser

NetworkPlane

TransportUser

NetworkPlane

Transport NetworkControl Plane

SignallingBearer(s)

DataBearer(s)

N d B

RNC

I bU

Node B

SMSC

/VLR GMSC

SS7 SS7


Iu-

CS

PSTN



Node B

RNC

IubUu

UENode B

Node B IubUuIur

SGSN GGSN

HLR EIR Auc

Iu-

PS

Gn Gi


UTRAN Core Network

PDN

Radio Access Network Application Part

(RANAP)

Key RANAP functions:

• Radio Access Bearer (between UE-CN)

• RAB Set-UP




Lähde: 3GPP TS 25410-360

• RAB Modification

• Clearing RAB

• Iu Bearer Release

• SRNC Relocation

• Paging Commands

Iu-CS

Q.2630.1

RANAP Iu UP Protocol

Layer

Transport

Network

Layer

TransportUser

Network Plane


TransportUser

Network Plane

Transport Network Control Plane

Radio

Network

Layer




Q.2150.1

Physical Layer

ATM

SSCOP

AAL5

SSCOP

SSCF-NNI

AAL2AAL5

MTP3bMTP3b

SCCP

SSCF-NNI


Iu-PS

SCCP

RANAPIu UP Protocol

Layer

Transport

Network

Layer

Transport

User

Network

Plane


Transport

User

Network

PlaneTransport Network

Control Plane

Radio

Network

Layer




SSCF-NNI

SSCOP

AAL5

IP

SCTP

SCCP

SSCF-NNI

MTP3-B

M3UA

Physical Layer

ATM

AAL5

IP

UDP

GTP-U

Physical Layer

ATM


Node B

RNC

IubUu

Node B

SMSC

/VLR GMSC

SS7 SS7


PSTN



Node B

RNC

IubUu

UENode B

Node B IubUuIur

SGSN GGSN

HLR EIR Auc

Gn Gi


UTRAN Core Network

PDN

CBCIu-

BC

Iu-BC

Transport

Network

Layer

Radio

Network

Layer SABP ProtocolLayer

SA Broadcast Plane

Transport

User

Network

Plane

•Between RNC andCommon Broadcast

Center CBC

•Service AreaB d P l





Layer

AAL5

IP

TCP

Physical Layer

ATM

•Service AreaBroadcast Protocol

(SABP)

Node B

RNC

IubUu

Node B

I

SMSC

/VLR GMSC

SS7 SS7


Iu-

CS

PSTN



Node B

RNC

IubUu

UENode B

IubUuIur

SGSN GGSN

HLR EIR Auc

Iu-

PS

Gn Gi


UTRAN Core Network

PDN

Radio Network Subsystem Application Part (RNSAP)

Key RNSAP Functions:

•Radio Link

• Management (between SRNC and DRNC)




• Reconfiguration (between SRNC and DRNC)

• Supervision (reports from DRNC to SRNC)

• Common Control Channel (CCCH) Signalling Transfer

• Paging

• Relocation Execution

Iur

RNSAP Iur Data

Stream(s)

TransportNetwork

Layer

TransportUser

NetworkPlane


TransportUser

NetworkPlane

Transport NetworkControl Plane

RadioNetwork

Layer

ALCAP(Q.2630.1)




SSCF-NNI

SSCOP

MTP3-B

AAL5

IP

SCTP

SCCP

AAL5

SSCF-NNI

STC (Q.2150.1)

Physical Layer

ATM

AAL2

SSCF-NNI

SSCOP

MTP3-B

IP

SCTPSSCF-NNI

M3UA M3UA


Node B

RNC

Uu

Node B

Iur

SMSC

/VLR GMSC

SS7 SS7


Iu-

CS

PSTN

Iub



Node B

RNC

IubUu

UENode B

Iur

SGSN GGSN

HLR EIR Auc

Iu-

PS

Gn Gi


UTRAN Core Network

PDN

ub

Node B Application Part (NBAP)

Key NBAP Functions:

• Cell Configuration Management

• Common Transport Channel Management




• System Information Management

• Configuration Verification/Alignment

• Measurements on Common Resources

• Radio Link Management & Supervision

Iub

Node B

Application Part

(NBAP)

Radio

Network

Layer

Radio Network

Control Plane

TransportNetwork

Control Plane

D C H F P

RA C H F P

D S C H F P

User Plane

F A C H F P

P C H F P

U S C H F P

C P C H F P





AAL Type 2

ALCAP

TransportLayer

Physical Layer

ATM

AAL Type 5

SSCF-UNI

SSCOP

AAL Type 5

SSCF-UNI

SSCOP

Q.2630.1

Q.2150.2

Node B

RNC

IubUu

Node B

Iur

SMSC

/VLR GMSC

SS7 SS7


Iu-

CS

PSTN



Node B

RNC

IubUu

UENode B

Iur

SGSN GGSN

HLR EIR Auc

Iu-

PS

Gn Gi


RNS

UTRAN Core Network

PDN

Node B

RNC

IubUu

Node B

Iur

SMSC

Server

GMSC

Server

HLR EIR A

Nb

SS7


Iu-

CS

PSTNMGW MGW

NcMc Mc



Node B

RNC

IubUu

UENode B

u

SGSN GGSN

HLR EIR Auc

Iu-

PS

Gn Gi


RNS

UTRAN Core Network

PDN

Node B

RNC

IubUu

Node B

Iur

CSCF

MGCF

HSS


PSTN

MGW

Cx

Gr MRF

SGW

Mr

Mg Mc



Node B

RNC

IubUu

UENode B

SGSN GGSN

Iu-

PS

Gn Gi


RNS

UTRAN Core Network

PDN

Mm

NOTE: Standardisation on-going!

MRF

Gi

SS7 signalling in UMTS Core

SCTP

M3UA

MTP-3 User Part

SSCF

MTP-3 B

MTP-3 User Part

SSCF

MTP-3 B

MTP-3 User Part

MTP-2

MTP-3

MTP-3 User Part





IP

ATM

AAL5

SCCOP

G.804

AAL5

SCCOP

MTP-1

MTP3 User Adaptation Layer (M3UA)

SCTP

M3UA

MTP-3 User Part




IP

Stream Control Transmission Protocol (SCTP)

SCTP

M3UA

MTP-3 User Part




IP


SCTP

M3UA

MTP-3 User Part




IP


SCTP

M3UA

MTP-3 User Part

Source Port Number Destination Port Number

Verification Tag

Checksum




IPChunk Type Chunk Flags Chunk Length

Chunk Value field

( information to be transferred in the chunk)

MAP

BICCS CCPRANAPBSSAPT CAP

INAP

ISUP

CAP



IPv4 (20 bytes), IPv6 (40 bytes)

Gbe,AT M, etc.

BICC

S CT P (16+Bytes)

H.248

S CCP

T CP(20)

RT PM3UA

ISUP

UDP (8)

5DGLR $FFHVV 1HWZRUN $UFKLWHFWXUH:LGHEDQG &'0$ V\VWHPV



4 ‹ 12.,$ 875$1 $UFKLWHFWXUH13372 39144133 2 $WWH /lQVLVDOPL

\

$WWH /lQVLVDOPL

5HVHDUFK 0DQDJHU

1RNLD 5HVHDUFK &HQWHU

$UFKLWHFWXUH DQG 1RGHV




875$1 DQG 6\VWHP $UFKLWHFWXUH

86,0

51&

,XE ,XU

8X

&X

516

1RGH %

,X

1RGH %

6*61

,X0&6

,X036

06& 2 9/5

+/5

*06& &6 H[W




875$1

,XE ,XU

&1

8(

0(

&X

516

51&

1RGH %

1RGH %

6*61

&%&

,X0%& **61 36 H[W

875$1 'HILQLWLRQV *HQHUDO

‡ :&'0$ UDGLR LV WKH PDLQ GLIIHUHQFH LQ 6UG JHQHUDWLRQ 875$1

FRPSDUHG WR *60 %66‡ 875$1 DUFKLWHFWXUH GHYHORSPHQW ZDV PDLQO\ EDVHG RQIDPLOLDU SULQFLSOHV DQG FRQFHSWV IURP *60

‡ 1R QHHG IRU FRQFHSWXDOO\ QHZ QHWZRUN HQWLWLHV

‡ 7KH HQWLWLHV LQ 875$1 DUH= 5DGLR 1HWZRUN &RQWUROOHU +51&, DQG% 6W WL +%6,




%DVH 6WDWLRQ +%6,‡ 1RWH WKDW VWDQGDUGV XVH WHUPLQRORJ\ 1RGH % IRU %DVH 6WDWLRQ

‡ $W D KLJK OHYHO WKHLU IXQFWLRQDOLW\ LV VLPLODU WR *60 %6& DQG %76UHVSHFWLYHO\

‡ 1HZ UHIHUHQFH SRLQW ,XU LV DGGHG EHWZHHQ 51&V IRU PDFURGLYHUVLW\ VRIW +2

‡ 51& KDV %JHQHUDO SXUSRVH% ,X LQWHUIDFH WR FRQQHFW WR &1

875$1 %DVLF &RQFHSWV

51&

51&

,XE ,XU

&1516

516

1RGH %

1RGH %

1RGH %

1RGH %

,X

‡ 875$1 FRQVLVWV RI D VHW RI 5DGLR 1HWZRUN6XEV\VWHPV FRQQHFWHG WR WKH &1 WKURXJK

,X1‡ 516 FRQVLVWV RI D 5DGLR 1HWZRUN

&RQWUROOHU DQG RQH RU PRUH 1RGH %V1 $1RGH % LV FRQQHFWHG WR WKH 51& WKURXJK

,XE LQWHUIDFH1‡ $ 1RGH % FDQ VXSSRUW )'' PRGH/ 7''




‡ 51& LV UHVSRQVLEOH IRU WKH +DQGRYHU GHFLVLRQV WKDW UHTXLUH VLJQDOOLQJ WR WKH8(1

‡ 51& FRPSULVHV D FRPELQLQJ2VSOLWWLQJ IXQFWLRQ WR VXSSRUW PDFUR GLYHUVLW\EHWZHHQ GLIIHUHQW 1RGH %1

‡ 1RGH % VXSSRUWLQJ WKH )'' PRGH FDQ FRPSULVH DQ RSWLRQDO

FRPELQLQJ2VSOLWWLQJ

IXQFWLRQ

WR

VXSSRUW

PDFUR

GLYHUVLW\

LQVLGH

D 1RGH

%

1

‡ ,QVLGH WKH 875$1/ WKH 51&V FDQ EH LQWHUFRQQHFWHG WRJHWKHU WKURXJK WKH ,XU1 ,XDQG ,XU DUH ORJLFDO LQWHUIDFHV1 ,XU FDQ EH FRQYH\HG RYHU SK\VLFDO GLUHFWFRQQHFWLRQ EHWZHHQ 51&V RU YLD DQ\ VXLWDEOH WUDQVSRUW QHWZRUN1

875$1PRGH RU GXDO0PRGH RSHUDWLRQ1



51& 5ROHV

‡ &RQFHUQLQJ RQH FRQQHFWLRQ EHWZHHQ 875$1 DQG RQH 8( / WKH

IROORZLQJ UROHV RI 51&V H[LVW=‡ 6HUYLQJ 51& WKDW FRQWUROV WKH FRQQHFWLRQV WR D 8(‡ 'ULIW 51& WKDW OHQGV LWV UHVRXUFHV IRU WKH 6HUYLQJ 51& IRU DSDUWLFXODU 8(

‡ (DFK 51& DOVR KDV WKH &RQWUROOLQJ 51& UROH WRZDUGV LWV 1RGH %V



: ‹ 12.,$ 875$1 $UFKLWHFWXUH13372 39144133 2 $WWH /lQVLVDOPL

51&

1RGH %

&1

6HUYLQJ

&1

&RQWUROOLQJ

6HUYLQJ 'ULIW'ULIW

&RQWUROOLQJ&RQWUROOLQJ &RQWUROOLQJ

'ULIW

*HQHUDO 3URWRFRO 3ULQFLSOHV LQ 875$1



; ‹ 12.,$ 875$1 $UFKLWHFWXUH13372 39144133 2 $WWH /lQVLVDOPL

$FFHVV 6WUDWXP DQG 1RQ0$FFHVV 6WUDWXP

1RQ0 $FFHVV 6WUDWXP

5DGLR

SURWRFROV+4,

5DGLR

SURWRFROV+4,

,X

SURWRFROV+5,

,X

SURWRFROV

+5,

&&/ 60/ 00/*00 +F0SODQH,>%FDOO% +X0SODQH,1+6,

&&/ 60/ 00/*00 +F0SODQH,>%FDOO% +X0SODQH,1+6,



< ‹ 12.,$ 875$1 $UFKLWHFWXUH13372 39144133 2 $WWH /lQVLVDOPL

‡ &RPPXQLFDWLRQ EHWZHHQ 8( DQG &1 LV LQ 1RQ0$FFHVV 6WUDWXP

‡ $FFHVV 6WUDWXP SURYLGHV VHUYLFHV IRU 1RQ $FFHVV 6WUDWXP

‡ 875$1 LV LQ WKH $FFHVV 6WUDWXP

‡ ,X LV LQ WKH $FFHVV 6WUDWXP

875$18( &1

$FFHVV 6WUDWXP

5DGLR+8X,

,X

*HQHUDO 3URWRFRO 0RGHO IRU 875$17HUUHVWULDO ,QWHUIDFHV

$SSOLFDWLRQ3URWRFRO

'DWD6WUHDP+V,

$/&$3+V,

7UDQVSRUW

1HWZRUN/D\HU

7UDQVSRUW8VHU

1HWZRUN3ODQH

&RQWURO 3ODQH 8VHU 3ODQH

7UDQVSRUW8VHU

1HWZRUN3ODQH

7UDQVSRUW 1HWZRUN&RQWURO 3ODQH

5DGLR

1HWZRUN/D\HU




‡ 7KH OD\HUV DQG SODQHV DUH ORJLFDOO\ LQGHSHQGHQW RI HDFK RWKHU

‡ ,I QHHGHG/ 7UDQVSRUW 1HWZRUN PD\ EH FKDQJHG LQ WKH IXWXUH E\GHFLVLRQV LQ WKH VWDQGDUGLVDWLRQ1

3K\VLFDO /D\HU

6LJQDOOLQJ%HDUHU +V,

6LJQDOOLQJ%HDUHU +V,

'DWD%HDUHU +V,

(OHPHQWDU\ 3URFHGXUHV +(3,

‡ 7KUHH FODVVHV=

‡ &ODVV 4= UHTXHVW DQG UHVSRQVH +IDLOXUH RU VXFFHVV,‡ &ODVV 5= UHTXHVW ZLWKRXW UHVSRQVH‡ &ODVV 6= UHTXHVW DQG SRVVLELOLW\ IRU PDQ\ UHVSRQVHV

‡ ,QGHSHQGHQW RI HDFK RWKHU +LQWHUDFWLRQV VSHFLILHG LQ VSHFLDOFDVHV,

6 I O G 8 I O +LI OL EO , L OO




‡ 6XFFHVVIXO DQG 8QVXFFHVVIXO +LI DSSOLFDEOH, RSHUDWLRQ DV ZHOO DV$EQRUPDO &RQGLWLRQV +LI DSSOLFDEOH, VSHFLILHG IRU HDFK (3

‡ (OHPHQWDU\ 3URFHGXUHV DUH VSHFLILHG LQ WKH LQWHUIDFHVSHFLILFDWLRQV +VWDJH 6 VSHFLILFDWLRQV,‡ 8VLQJ VHYHUDO (3V WRJHWKHU LV VSHFLILHG LQ VWDJH 5 VLJQDOOLQJIORZ VSHFLILFDWLRQV

&OLHQW 0 6HUYHU PRGHO

‡ %HKDYLRXU RI &OLHQW XQVSHFLILHG +RQO\ XVDJH RI RSWLRQDO ,(VVSHFLILHG,

‡ %HKDYLRXU RI 6HUYHU VSHFLILHG FOHDUO\ DQG WKRURXJKO\




&OLHQWQR TXHVWLRQV ZK\

6HUYHUGHWDLOHG VHUYLFH

5HTXHVW

%DFNZDUGV DQG )RUZDUGV &RPSDWLELOLW\

‡ 6R FDOOHG %&RPSUHKHQVLRQ 5HTXLUHG% SULQFLSOH DSSOLHG

‡ 1R YHUVLRQ QXPEHU LQ PHVVDJHV‡ 3URFHGXUHV DQG PDLQ ,(V KDYH %H[SOLFLW ,'% DQG %&ULWLFDOLW\%LQGLFDWLQJ ZKDW LV UHTXHVWHG IURP WKH UHFHLYHU LI QRW XQGHUVWRRG

‡ 7KH VWUXFWXUH IRU ,' DQG FULWLFDOLW\ FDQ DOZD\V EH GHFRGHG/ L1H1 WKDWVWUXFWXUH LV QHYHU FKDQJHG




‡ $OORZV ,(V IURP GLIIHUHQW VWDQGDUG YHUVLRQV LQ RQH PHVVDJH

‡ 5HTXLUHV KDQGOLQJ RI LQIRUPDWLRQ DERYH WKH $6114 HQ2GHFRGLQJ5$1$3 3'8

W\SH RI

PHVVDJH 5$1$3 PHVVDJH YDOXH

SURFHGXUH

FRGHSURFHGXUHFULWLFDOLW\

,G/ FULWLFDOLW\/ YDOXH

,G/ FULWLFDOLW\/ YDOXH1 1 1

,X ,QWHUIDFH




,X ,QWHUIDFH &RQFHSW

86,0

51&

,XE ,XU

8X

&X516

1RGH %,X

1RGH %

6*61

,X0&6

,X0

36

06& 2 9/5

$FFHVV 1RGHIRU &60GRPDLQ

$FFHVV 1RGHIRU 360GRPDLQ




875$1

&1

8(

0(

516

51&

1RGH %

1RGH %

&%&

,X0%&

$FFHVV 1RGHIRU %&0GRPDLQ

,X )XQFWLRQDO 6SOLW 3ULQFLSOHV

‡ $OO 5DGLR 5HODWHG PDWWHUV LQ 5DGLR 1HWZRUN DQG DOO 6HUYLFH

5HODWHG PDWWHUV LQ &1‡ 0RVW )XQFWLRQV LQ ,X LQFOXGH ERWK DVSHFWV

‡ 6SOLW UHVSRQVLELOLW\‡ 875$1 SURYLGHV 6HUYLFHV WR WKH &1

‡ 8VXDO FDVH= &1 %FRQWUROV% DQG 875$1 %SURYLGHV%




,X &6 3URWRFRO 6WUXFWXUH

7UDQVSRUW8VHU

1HWZRUN3ODQH

&RQWURO 3ODQH 8VHU 3ODQH

7UDQVSRUW8VHU

1HWZRUN3ODQH


5DGLR

1HWZRUN

/D\HU ,X 8VHU 3ODQH3URWRFRO

4 5483 4

41596314

5$1$3

6&&3

7UDQVSRUW

1HWZRUN

/D\HU



4: ‹ 12.,$ 875$1 $UFKLWHFWXUH13372 39144133 2 $WWH /lQVLVDOPL

3K\VLFDO /D\HU

$70

$$/5

41548314

$$/8

66&23

66&)011,

0736E

66&23

$$/8

0736E

6&&3

66&)0

11,

,X 36 3URWRFRO 6WUXFWXUH

7UDQVSRUW8VHU

1HWZRUN3ODQH


7UDQVSRUW

8VHU

1HWZRUN

3ODQH

6&&3

5$1$3

&RQWURO 3ODQH

,X 8VHU 3ODQH3URWRFRO

8VHU 3ODQH5DGLR

1HWZRUN

/D\HU

7UDQVSRUW

1HWZRUN

/D\HU



4; ‹ 12.,$ 875$1 $UFKLWHFWXUH13372 39144133 2 $WWH /lQVLVDOPL

66&)011,

66&23

07360%

$$/8

,36&73

6&&3

068$

3K\VLFDO /D\HU

$70

$$/8

,38'3

*7308

3K\VLFDO /D\HU

$70

1RWKLQJ $

5$1$3 )XQFWLRQV 425

‡ 5DGLR $FFHVV %HDUHU +8( 0 &1 EHDUHU, KDQGOLQJ +FRPELQHG SURFHGXUH,>

‡ 5$% 6HW0XS +,QFOXGLQJ 4XHXLQJ,‡ 5$% 0RGLILFDWLRQ

‡ &OHDULQJ 5$% +,QFOXGLQJ 5$1 LQLWLDWHG FDVH,

‡ ,X 5HOHDVH> 5HOHDVHV DOO ,X UHVRXUFHV +6LJQDOLQJ OLQN DQG 803ODQH, UHODWHG WR WKH

VSHFLILHG 8(1 $OVR LQFOXGHV 5$1 LQLWLDWHG FDVH1

‡ 5HORFDWLRQ> +DQGOLQJ ERWK 6516 5HORFDWLRQ +8( DOUHDG\ LQ WDUJHW 51& ZLWK



4< ‹ 12.,$ 875$1 $UFKLWHFWXUH13372 39144133 2 $WWH /lQVLVDOPL

,XU, DQG +DUG +DQGRYHU +VLPXOWDQHRXV VZLWFK RI 5DGLR DQG ,X,1 ,QFOXGHV /RVV0OHVV UHORFDWLRQ DQG ,QWHU V\VWHP +DQGRYHU

‡ 3DJLQJ= &1 WR SDJH DQ LGOH 8( IRU D WHUPLQDWLQJ FDOO2FRQQHFWLRQ

‡ &RPPRQ ,'= 8( 1$6 ,G VHQW WR 51& IRU SDJLQJ FR0RUGLQDWLRQ

‡ 7UDFH ,QYRFDWLRQ= &1 PD\ UHTXHVW 875$1 WR VWDUW2VWRS WUDFLQJ D VSHFLILF 8(

‡ 6HFXULW\ 0RGH &RQWURO> &RQWUROV &LSKHULQJ DQG ,QWHJULW\ &KHFNLQJ1

5$1$3 )XQFWLRQV 525

‡ /RFDWLRQ 5HSRUWLQJ> 5HTXHVWLQJ +&1, DQG UHSRUWLQJ +51&, 8( ORFDWLRQ

‡ 'DWD 9ROXPH 5HSRUWLQJ> 5HTXHVWLQJ +&1, DQG UHSRUWLQJ +51&, 8QVXFFHVVIXOO\WUDQVPLWWHG '/ GDWD

‡ ,QLWLDO 8( 0HVVDJH= &DUULHV WKH ILUVW 1$6 PHVVDJH WR WKH &1 DQG VHWV XS WKH ,XVLJQDOOLQJ FRQQHFWLRQ1

‡ 'LUHFW 7UDQVIHU= &DUULHV 1$6 VLJQDOOLQJ LQIRUPDWLRQ RYHU ,X1 &RQWHQW QRW 875$1LQWHUSUHWHG E\ 875$1




S \

‡ &1 ,QIRUPDWLRQ %URDGFDVW > 7KLV SURFHGXUH DOORZV WKH &1 WR VHW &1 + 1$6 , UHODWHG

V\VWHP LQIRUPDWLRQ WR EH EURDGFDVW WR DOO XVHUV 1 :,// %( '(/(7(' IURP 5 <<$ ‡ 2YHUORDG> 8VHG IRU IORZ FRQWURO +WR UHGXFH IORZ, RYHU WKH ,X LQWHUIDFH H1J1 GXH

WR SURFHVVRU RYHUORDG DW &1 RU 875$1

‡ 5HVHW> ,W LV XVHG WR UHVHW WKH &1 RU WKH 875$1 VLGH RI ,X LQWHUIDFH LQ HUURUVLWXDWLRQV1 ,QFOXGHV DOVR UHVHWWLQJ 6LJQDOOLQJ &RQQHFWLRQ

‡ (UURU ,QGLFDWLRQ> 8VHG IRU SURWRFRO HUURUV ZKHUH QR RWKHU HUURU DSSOLHV

,X ,QWHUIDFH )XQFWLRQDO ([DPSOH




9/ 5&

51&

9/ 5&

51&

9/ 5&

51&

&RQQHFWLRQV LQ 6HUYLQJ 51& 5HORFDWLRQ

9/ 506&

06&29/5

9/ 5&

51&

9/ 506&

06&29/5

6RXUFH6HUYLQJ

7DUJHW'ULIW 6HUYLQJ




%76%76%76%76

6HUYLQJ 51& 5HORFDWLRQ WULJJHUHG 5HVXOWLQJ &RQQHFWLRQ

5HORFDWLRQ/ 8( 1RW ,QYROYHG8( 6RXUFH 51& 7DUJHW 51&&1 1RGH

41 5HORFDWLRQ 5HTXLUHG

51 5HORFDWLRQ 5HTXHVW

61 5HORFDWLRQ 5HTXHVW $FNQRZOHGJH

71 5HORFDWLRQ &RPPDQG

5HORFDWLRQ 'HFLVLRQ

81 6WDUW 'DWD)RUZDUGLQJ




:1 5HORFDWLRQ &RPSOHWH

;1 ,X 5HOHDVH &RPPDQG

<1 ,X 5HOHDVH &RPSOHWH

91 5HORFDWLRQ 'HWHFW

91 55& 3URFHGXUHV +517, 5H0DOORFDWLRQ FRPSOHWH,

81 516$3 5HORFDWLRQ &RPPLW

5HORFDWLRQ/ 8( ,QYROYHG8( 6RXUFH 51& 7DUJHW 51&&1 1RGH

41 5HORFDWLRQ 5HTXLUHG

51 5HORFDWLRQ 5HTXHVW

61 5HORFDWLRQ 5HTXHVW $FNQRZOHGJH

71 5HORFDWLRQ &RPPDQG

5HORFDWLRQ 'HFLVLRQ

8 55& %+ G & G%

81 6WDUW 'DWD)RUZDUGLQJ




:1 %+DQGRYHU $FFHVV%

<1 5HORFDWLRQ &RPSOHWH

431 ,X 5HOHDVH &RPPDQG

441 ,X 5HOHDVH &RPSOHWH

91 )RUZDUG 6516 &RQWH[W

;1 5HORFDWLRQ 'HWHFW

;1 55& SURFHGXUHV

81 55&= %+DQGRYHU &RPPDQG%

81 )RUZDUG 6516 &RQWH[W

,X %& 3URWRFRO 6WUXFWXUH

6$%3

7UDQVSRUW

1HWZRUN

/D\HU

6HUYLFH

$UHD

%URDGFDVW

3ODQH

7UDQVSRUW

8VHU

1HWZRUN

3ODQH

5DGLR

1HWZRUN

/D\HU




$$/8

,3

7&3

3K\VLFDO /D\HU

$70

6$%3 )XQFWLRQV

‡ 0HVVDJH +DQGOLQJ1 7KLV IXQFWLRQ LV UHVSRQVLEOH IRU WKH EURDGFDVW

RI QHZ PHVVDJHV/ UHSODFLQJ H[LVWLQJ EURDGFDVWHG PHVVDJHV DQG WRVWRS WKH EURDGFDVWLQJ RI VSHFLILF PHVVDJHV1 $OVR PHVVDJH VWDWXVLQTXLU\ LV LQFOXGHG1

‡ /RDG +DQGOLQJ1 7KLV IXQFWLRQ LV UHVSRQVLEOH IRU GHWHUPLQLQJ WKHORDGLQJ RI WKH EURDGFDVW FKDQQHOV DW DQ\ SDUWLFXODU SRLQW LQ WLPH1

‡ 5HVHW 7KLV IXQFWLRQ SHUPLWV WKH &%& WR HQG EURDGFDVWLQJ LQ RQH




‡ 5HVHW1 7KLV IXQFWLRQ SHUPLWV WKH &%& WR HQG EURDGFDVWLQJ LQ RQHRU PRUH 6HUYLFH $UHDV1 $OVR 5HVWDUW LQGLFDWLRQ LV LQFOXGHG1

‡ (UURU DQG )DLOXUH +DQGOLQJ1 7KLV IXQFWLRQ DOORZV WKH UHSRUWLQJ RI JHQHUDO DQG IXQFWLRQ VSHFLILF HUURU VLWXDWLRQV1

,X )UDPH +DQGOLQJ 3URWRFRO




0RGHV RI 2SHUDWLRQ

‡ 7UDQVSDUHQW 0RGH

‡ )RU 5$%V UHTXLULQJ QR VSHFLDO KDQGOLQJ IURP ,X‡ 2QO\ WUDQVSRUW RI WKH XVHU GDWD ZLWKRXW IUDPLQJ

‡ 8VDJH ([DPSOH = *73 3'8V +36 GRPDLQ,

‡ 6XSSRUW 0RGH IRU SUHGHILQHG 6'8 VL]H‡ 3URYLGHV VSHFLDO VHUYLFHV IRU KDQGOLQJ 5$%V‡ 8VHV IUDPLQJ RI XVHU GDWD




‡ 8VHV IUDPLQJ RI XVHU GDWD‡ 6 3'8 7\SHV=

‡ FRQWURO GDWD +3'8 7\SH 47,‡ XVHU GDWD ZLWK HUURU GHWHFWLRQ VFKHPH +3'8 7\SH 3,/‡ XVHU GDWD ZLWKRXW HUURU GHWHFWLRQ VFKHPH +3'8 7\SH 4,

‡ 8VDJH ([DPSOH = $05 VSHHFK 3'8V +&6 GRPDLQ,

6XSSRUW 0RGH &RQWURO )XQFWLRQV

‡ ,QLWLDOLVDWLRQ

‡ 7UDQVIHU RI 8VHU 'DWD‡ 7UDQVIHU RI 8VHU 'DWD 3'8 PD\ LQFOXGH )UDPH 4XDOLW\ &ODVVLILFDWLRQ

‡ 5DWH &RQWURO‡ 7LPH $OLJQPHQW

‡ + GOL I ( ( W




‡ +DQGOLQJ RI (UURU (YHQW

,XU ,QWHUIDFH




‡ $OORZV LQWHU 51& 85$ XSGDWH DQG

SDJLQJ LQ PXOWLSOH 51&V +8VHU LQ55& 85$B3&+ +RU &(//B3&+,VWDWH,1

)XQFWLRQDO 0RGXOHV +426,6XSSRUW EDVLF LQWHU 51& PRELOLW\

&1

6051& 51&

‡ $OORZV WKH ,QWHU 51& FHOO XSGDWH

. 651& UHORFDWLRQ +8VHU LQ 55&&(//B)$&+ VWDWH,1

&1

6051& 7DUJHW

51&

651& 5HORFDWLRQ




06

%6 %6%6

06

%6%6

85$

&HOO 8SGDWH

‡ 2QO\ VLJQDOOLQJ/ QR XVHU GDWD

‡ 1RWH= ,XU LQWHUIDFH GRHV QRW QHHG WR EH LQYROYHG LQ ,QWHU 51& KDUGKDQGRYHU

85$ 8SGDWH

SDJLQJ SDJLQJ



)XQFWLRQDO 0RGXOHV +626,6XSSRUW FRPPRQ FKDQQHO WUDIILF EHWZHHQ WZR 51&V

&1

%6

6051& '051&

‡ $OORZV DQFKRULQJ RI 651& DOVR ZKHQ8( LV LQ FRPPRQ FKDQQHO+5$&+2)$&+, VWDWH

‡ 6XSSRUW XVHU GDWD WUDQVIHU ZLWK

FRPPRQ WUDQVSRUW FRQQHFWLRQ

‡ %HQHILWV XQFOHDU IRU EHVW HIIRUW WUDIILF +UHGXFHG VLJQDOOLQJ ORDG LQ &1 EXW




‡ $OVR IRXUWK PRGXOH *OREDO/ ZLWK (UURU ,QGLFDWLRQ IXQFWLRQDOLW\H[LVWV

06

+ UHGXFHG VLJQDOOLQJ ORDG LQ &1 / EXW

LQFUHDVHG FRPSOH[LW\ LQ 875$1 DQG OHVV HIILFLHQW XVH RI UDGLR UHVRXUFH ,1

,XU SURWRFRO VWUXFWXUH

415483146&&3

516$3

&RQWURO

3ODQH 8VHU

3ODQH5DGLR

1HWZRUN

/D\HU

&&+)3

'&+)3

7UDQVSRUW

1HWZRUN

/D\HU

7UDQVSRUW8VHU

1HWZRUN 3ODQH

7UDQVSRUW8VHU

1HWZRUN 3ODQH

7UDQVSRUW 1HWZRUN

&RQWURO 3ODQH

41596314




$$/8

66&)0 11,

66&23

07360%

$$/8

,3

6&73

068$

66&23 ,3

3K\VLFDO /D\HU

$70

$$/5

66&)0 11,

07360%

6&73

068$

516$3 )XQFWLRQV 425

• 5DGLR /LQN 0DQDJHPHQW1 7KLV IXQFWLRQ DOORZV WKH 651& WR PDQDJH UDGLR OLQNV

XVLQJ GHGLFDWHG

UHVRXUFHV

LQ

D '516

1

• 3K\VLFDO &KDQQHO 5HFRQILJXUDWLRQ1 7KLV IXQFWLRQ DOORZV WKH '51& WR UHDOORFDWHWKH SK\VLFDO FKDQQHO UHVRXUFHV IRU D 5DGLR /LQN1

• 5DGLR /LQN 6XSHUYLVLRQ1 7KLV IXQFWLRQ DOORZV WKH '51& WR UHSRUW IDLOXUHV DQGUHVWRUDWLRQV RI D 5DGLR /LQN1

• &RPSUHVVHG 0RGH &RQWURO >)''@1 7KLV IXQFWLRQ DOORZV WKH 651& WR FRQWURO WKHXVDJH RI FRPSUHVVHG PRGH ZLWKLQ D '516




XVDJH RI FRPSUHVVHG PRGH ZLWKLQ D '516

• 0HDVXUHPHQWV RQ 'HGLFDWHG 5HVRXUFHV1 7KLV IXQFWLRQ DOORZV WKH 651& WRLQLWLDWH PHDVXUHPHQWV RQ GHGLFDWHG UHVRXUFHV LQ WKH '5161 7KH IXQFWLRQ DOVRDOORZV WKH '51& WR UHSRUW WKH UHVXOW RI WKH PHDVXUHPHQWV1

• '/ 3RZHU 'ULIWLQJ &RUUHFWLRQ >)''@1 7KLV IXQFWLRQ DOORZV WKH 651& WR DGMXVWWKH '/ SRZHU OHYHO RI RQH RU PRUH 5DGLR /LQNV LQ RUGHU WR DYRLG '/ SRZHUGULIWLQJ EHWZHHQ WKH 5DGLR /LQNV1

516$3 )XQFWLRQV 525

• &&&+ 6LJQDOOLQJ 7UDQVIHU1 7KLV IXQFWLRQ DOORZV WKH 651& DQG '51& WR SDVV

LQIRUPDWLRQ EHWZHHQ

WKH

8(

DQG

WKH

651&

RQ

D &&&+

FRQWUROOHG

E\

WKH

'516

1

• 3DJLQJ1 7KLV IXQFWLRQ DOORZV WKH 651& WR SDJH D 8( LQ D 85$ RU D FHOO LQ WKH'5161

• &RPPRQ 7UDQVSRUW &KDQQHO 5HVRXUFHV 0DQDJHPHQW1 7KLV IXQFWLRQ DOORZV WKH651& WR XWLOLVH &RPPRQ 7UDQVSRUW &KDQQHO 5HVRXUFHV ZLWKLQ WKH '516+H[FOXGLQJ '6&+ UHVRXUFHV IRU )'',1

• 5HORFDWLRQ ([HFXWLRQ 7KLV IXQFWLRQ DOORZV WKH 651& WR ILQDOLVH D 5HORFDWLRQ




• 5HORFDWLRQ ([HFXWLRQ1 7KLV IXQFWLRQ DOORZV WKH 651& WR ILQDOLVH D 5HORFDWLRQSUHYLRXVO\ SUHSDUHG YLD RWKHU LQWHUIDFHV1

• 5HSRUWLQJ JHQHUDO HUURU VLWXDWLRQV1 7KLV IXQFWLRQ DOORZV UHSRUWLQJ RI JHQHUDOHUURU VLWXDWLRQV/ IRU ZKLFK IXQFWLRQ VSHFLILF HUURU PHVVDJHV KDYH QRW EHHQGHILQHG1

,XE ,QWHUIDFH




/RJLFDO 0RGHO RI 1RGH % LQ )''111 111

1RGH %

&RQWURO

3RUW

,XE

5$&+

'DWD

SRUW

,XE

)$&+

'DWD

SRUW

,XE

3&+

'DWD

SRUW

&RPPXQLFDWLRQ

&RQWURO

3RUW

,XE

7'' 86&+

'DWD

SRUW

,XE

'&+

'DWD

SRUW

,XE

'6&+

'DWD

SRUW

&RPPXQLFDWLRQ

&RQWURO

3RUW

,XE

7'' 86&+

'DWD

SRUW

,XE

'&+

'DWD

SRUW

,XE

'6&+

'DWD

SRUW

&RQWUROOLQJ 51&




1RGH %

111

&HOO &HOO &HOO &HOO &HOO&HOO

1RGH % &RPPXQLFDWLRQ &RQWH[WV/

ZLWK DWWULEXWHV

&RPPRQ 7UDQVSRUW &KDQQHOV/

ZLWK DWWULEXWHV

7UDIILF WHUPLQDWLRQ SRLQW 7UDIILF WHUPLQDWLRQ SRLQW

,XE 3URWRFRO 6WUXFWXUH

41548315

1%$3

7UDQVSRUW

1HWZRUN

/D\HU

7UDQVSRUW

8VHU

1HWZRUN

3ODQH

&RQWURO

3ODQH 8VHU 3ODQH

7UDQVSRUW

8VHU

1HWZRUN

3ODQH7UDQVSRUW 1HWZRUN

&RQWURO 3ODQH

5DGLR

1HWZRUN

/D\HU

41596314

'

& + ) 3

5$

& + ) 3

' 6 & + ) 3

) $

& + ) 3

3 &

+

) 3

8 6 & + ) 3




$$/8

66&23

66&)081,

4

66&23

$$/8

66&)081,

3K\VLFDO /D\HU

$70

$$/5

1%$3 )XQFWLRQV 425

‡ &HOO &RQILJXUDWLRQ 0DQDJHPHQW1 7KLV IXQFWLRQ JLYHV WKH &51& WKH SRVVLELOLW\WR PDQDJH WKH FHOO FRQILJXUDWLRQ LQIRUPDWLRQ LQ D 1RGH %1

‡ &RPPRQ 7UDQVSRUW &KDQQHO 0DQDJHPHQW1 7KLV IXQFWLRQ JLYHV WKH &51& WKHSRVVLELOLW\ WR PDQDJH WKH FRQILJXUDWLRQ RI &RPPRQ 7UDQVSRUW &KDQQHOV LQ D1RGH %1

‡ 6\VWHP ,QIRUPDWLRQ 0DQDJHPHQW1 7KLV IXQFWLRQ JLYHV WKH &51& WKH DELOLW\ WRPDQDJH WKH VFKHGXOLQJ RI 6\VWHP ,QIRUPDWLRQ WR EH EURDGFDVW LQ D FHOO1

‡ 5HVRXUFH (YHQW 0DQDJHPHQW1 7KLV IXQFWLRQ JLYHV WKH 1RGH % WKH DELOLW\ WRL I WK &51& E W WK W W I 1 G %




LQIRUP WKH &51& DERXW WKH VWDWXV RI 1RGH % UHVRXUFHV1

‡ &RQILJXUDWLRQ $OLJQPHQW1 7KLV IXQFWLRQ JLYHV WKH &51& DQG WKH 1RGH % WKHSRVVLELOLW\ WR YHULI\ WKDW ERWK QRGHV KDV WKH VDPH LQIRUPDWLRQ RQ WKHFRQILJXUDWLRQ RI WKH UDGLR UHVRXUFHV1

‡ 0HDVXUHPHQWV RQ &RPPRQ 5HVRXUFHV1 7KLV IXQFWLRQ DOORZV WKH &51& WRLQLWLDWH PHDVXUHPHQWV LQ WKH 1RGH %1 7KH IXQFWLRQ DOVR DOORZV WKH 1RGH % WRUHSRUW WKH UHVXOW RI WKH PHDVXUHPHQWV1

1%$3 )XQFWLRQV 525

‡ 6\QFKURQLVDWLRQ 0DQDJHPHQW1+7'', 7KLV IXQFWLRQ DOORZV WKH &51& WR PDQDJHWKH V\QFKURQLVDWLRQ RI D 7'' FHOO LQ D 1RGH %1

‡ 5DGLR /LQN 0DQDJHPHQW1 7KLV IXQFWLRQ DOORZV WKH &51& WR PDQDJH UDGLR OLQNVXVLQJ GHGLFDWHG UHVRXUFHV LQ D 1RGH%1

‡ 5DGLR /LQN 6XSHUYLVLRQ1 7KLV IXQFWLRQ DOORZV WKH &51& WR UHSRUW IDLOXUHV DQG

UHVWRUDWLRQV RI D 5DGLR /LQN1

‡ 0HDVXUHPHQWV RQ 'HGLFDWHG 5HVRXUFHV1 7KLV IXQFWLRQ DOORZV WKH &51& WRLQLWLDWH PHDVXUHPHQWV LQ WKH 1RGH%1 7KH IXQFWLRQ DOVR DOORZV WKH 1RGH% WRUHSRUW WKH UHVXOW RI WKH PHDVXUHPHQWV




UHSRUW WKH UHVXOW RI WKH PHDVXUHPHQWV1

‡ '/ 3RZHU 'ULIWLQJ &RUUHFWLRQ +)'',1 7KLV IXQFWLRQ DOORZV WKH &51& WR DGMXVWWKH '/ SRZHU OHYHO RI RQH RU PRUH 5DGLR /LQNV LQ RUGHU WR DYRLG '/ SRZHUGULIWLQJ EHWZHHQ WKH 5DGLR /LQNV1

‡ 5HSRUWLQJ JHQHUDO HUURU VLWXDWLRQV1 7KLV IXQFWLRQ DOORZV UHSRUWLQJ RI JHQHUDOHUURU VLWXDWLRQV/ IRU ZKLFK IXQFWLRQ VSHFLILF HUURU PHVVDJHV KDYH QRW EHHQGHILQHG1

,XU DQG

,XE

)UDPH

+DQGOLQJ

3URWRFROV




,XU ) ,XE )UDPH 3URWRFROV

‡ 'HGLFDWHG &KDQQHO )UDPH 3URWRFRO

‡ 2QH FRPPRQ SURWRFRO IRU ,XU DQG ,XE ,QWHUIDFHV‡ &RPPRQ &DQQHO )UDPH 3URWRFROV

‡ 6HSDUDWH SURWRFROV IRU ,XU DQG ,XE ,QWHUIDFHV

‡ $OO RI WKHP LQFOXGH‡ &RQWURO )XQFWLRQV +0RVWO\ VLPLODU DV LQ ,X )UDPH 3URWRFRO,‡ 'DWD )UDPH 7UDQVIHU




WCDMA Physical Layer (Chapter 6)

Peter Chong, Ph.D. (UBC, Canada)

Research Engineer



1 26.01.2002 WCDMA Phys ical Layer

Nokia Research Center, Helsinki, Finland



Some Parameters of WCDMA Physical Layer

Carrier Spacing 5 MHz (nominal)

Chip Rate 3.84 Mcps

Frame Length 10 ms (38400 chips)

No. of slots/frame 15

No. of chips/slot 2560 chips (Max. 2560 bits)




Uplink SF 4 to 256

Downlink SF 4 to 512

Channel Rate 7.5 Kbps to 960 Kbps

Spreading and Scrambling




Spreading Operation

• Spreading means increasing the signal bandwidth

• Strickly speaking, spreading includes two operations:

• Channelisation (increases signal bandwidth) - using orthogonalcodes

• Scrambling (does not affect the signal bandwidth) - using pseudo-noise codes

channelization codes (SF) scrambling codes




Data

bit rate chip rate chip rate

Channelisation (1/3)

• Channelisation codes are orthogonal codes, based on Orthogonal

Variable Spreading Factor (OVSF) technique• The codes are fully orthogonal, i.e., they do not interfere with each

other, only if the codes are time synchronized

• Thus, channelisation codes can separate the transmissions from a

single source• In the downlink, it can separate different users within one cell/sector

• Limited orthogonal codes must be reused in every cell




• Problem: Interference if two cells use the same code• Solution: Scrambling codes to reduce inter-base-station interference


• In the uplink, it can only separate the physical channels/services of one

user because the mobiles are not synchronised in time.• It is possible that two mobiles are using the same codes.

• In order to separate different users in the uplink, scrambling codes are

used.• The channelisation codes are picked from the code tree as shown in

next slide.




• One code tree is used with one scrambling code on top of the tree.• If c4,4 is used, no codes from its subtree can be used (c8,7 , c8,8 , …).


Code tree

(c)(c,c)

c1,1

=(1)

c2,1=(1,1)

c2 2=(1 -1)

c4,1=(1,1,1,1)

c4,2=(1,1,-1,-1)

c4,3=(1,-1,1,-1)

c4,4=(1,-1,-1,1)

. . .

c8,1

c8,2

c8,3

c8,4

c8,5

c8,6

c8,7




(c,-c)

. . .

c2,2=(1, 1)

SF=1 SF=2 SF=4 SF=8

8,7

c8,8

Scrambling

• In the scrambling process the code sequence is multiplied with a

pseudorandom scrambling code.

• The scrambling code can be a long code (a Gold code with 10 ms

period) or a short code (S(2) code).

• In the downlink scrambling codes are used to reduce the inter-base-

station interference. Typically, each Node B has only one scrambling

code for UEs to separate base stations. Since a code tree under one




scrambling code is used by all users in its cell, proper codemanagement is needed.

• In the uplink scrambling codes are used to separate the terminals.

SummaryChannelisation code Scrambling code

Usage UL: Separation of physcial dataand control channels from same UE

DL: Seperation of different users

within one cell

UL: Separation of terminalsDL: Separation of

cells/sectors

Length UL:4 – 256 chips same as SFDL:4 – 512 chips same as SF

UL: 10ms=38400 chipsDL: 10ms=38499 chips

No. of

codes

No. of codes under one scrambling

code = SF

UL: Several millions

DL: 512

Limited codes in eachcell for DL.

38400




Code

family

Orthogonal Variable Spreading

Factor

Long 10ms code: Gold code

Short code: Extended S(2)

code family

Spreading Yes, increase transmission

bandwidth

No, does not affect

transmission bandwidth

Transport Channels




Channel Concepts• Three separate channels concepts in the UTRA: logical, transport, and

physical channels.

• Logical channels define what type of data is transferred.

• Transport channels define how and with which type of characteristics thedata is transferred by the physical layer.

• Physical data define the exact physical characteristics of the radio channel.

RLC layer

L2Logical Channel




MAC layer

PHY layer L1

Transport Channel

Physical Channel

Transport Channels -> Physical Channels(1/3)

• Transport channels contain the data generated at the higher layers,

which is carried over the air and are mapped in the physical layer todifferent physical channels.

• The data is sent by transport block from MAC layer to physical layer

and generated by MAC layer every 10 ms.

• The transport format of each transport channel is identified by theTransport Format Indicator (TFI), which is used in the interlayercommunication between the MAC layer and physical layer.




• Several transport channels can be multiplexed together by physicallayer to form a single Coded Composite Transport Channel

(CCTrCh).

Transport Channels -> Physical Channels(2/3)

• The physical layer combines several TFI information into the

Transport Format Combination Indicator (TFCI), which indicatewhich transport channels are active for the current frame.

• Two types of transport channels: dedicated channels and common

channels.

• Dedicated channel –reserved for a single user only.

• Support fast power control and soft handover.

• Common channel – can be used by any user at any time.




• Don’t support soft handover but some support fast power control.

• In addition to the physical channels mapped from the transportchannels, there exist physical channels for signaling purposes to

carry only information between network and the terminals.

Transport Channels -> Physical Channels (3/3)

Synchronisation channel SCH

Physical downlink shared channel PDSCH(DL) Downlink shared channel DSCH

Secondary common control physical channel S-CCPCH(DL) Forward access channel FACH

(DL) Paging channel PCH

Primary common control physical channel P-CCPCH(DL) Broadcast channel BCH

Physical common packet channel PCPCH(UL) Common packet channel CPCH

Physical random access channel PRACH(UL) Random access channel RACH

Dedicated physical data channel DPDCH

Dedicated physical control channel DPCCH

(UL/DL) Dedicated channel DCH

Physical ChannelTransport Channel




Common pilot channel CPICH

Collision detection/Channel assignment indicator channelCD/CA-ICH

CPCH Status indication channel CSICH

Paging indication channel PICH

Acquisition indication channel AICHSignaling physical channels

UL Dedicated Channel DCH (1/3)• Due to audible interference to the audio equipment caused from the

discontinuous UL transmission, two dedicated physical channels are

I-Q/code multiplexing (called dual-channel QPSK modulation)instead of time multiplexing.

Data (DPDCH) Data (DPDCH)DTX Period

Layer 1 Control Information (DPCCH)

channelization code, c Dcomplex

scrambling code




*j

Data(DPDCH)

Control

(DPDCH)

channelization code, cC

I+jQ

BPSK for each channel

UL Dedicated Channel DCH (2/3)• Dedicated Physical Control Channel (DPCCH) has a fixed spreading factor

of 256 and carries physical layer control information.

• DPCCH has four fields: Pilot, TFCI, FBI, TPC.Pilot – channel estimation + SIR estimate for PC

TFCI – bit rate, channel decoding, interleaving parameters for everyDPDCH frame

FBI (Feedback Information) – transmission diversity in the DLTPC (Transmission Power Control) – power control command

2560 chips




DataDPDCH

DPCCH PILOT TFCI FBI TPC

0 21 14Uplink DPCH

10 ms

UL Dedicated Channel DCH (3/3)

•Dedicated Physical Data Channel (DPDCH) has a spreading factorfrom 4 to 256 and its data rate may vary on a frame-by-frame basis.

•Parallel channel codes can be used in order to provide 2 Mbps userdata

30 kbps6064

15 kbps30128

7.5 kbps15256

Max. user data rate with ½rate coding (approx.)

DPDCH channelbit rate (kbps)

DPDCH SF

3.84 Mcps/256=15 kbps




2.3 Mbps57404, with 6 parallel codes

480 kbps9604

240 kbps4808

120 kbps24016

60 kbps12032

UL Multiplexing and Channel Coding Chain

CRC attachment

TrBlk concatenation/ code block

segmenation

Channel coding

Radio frameequalization

1 i l i

TrCH 1

. . .

Ph CH i

2nd (intra-frame)interleaving

PhyCH mapping

DPDCH#1 DPDCH#2 … DPDCH#N

TrCH 2

O h T CH




1st interleaving

Radio framesegmentation

Rate matching

TrCH multiplexing

PhyCH segmentationOther TrCHs

CCTrCh

DL Dedicated Channel DCH (1/3)• In the DL no audible interference is generated with DTX because the

common channels are continuously transmitting.

• Downlink DCH is transmitted on the Downlink Dedicated Physical

Channel (Downlink DPCH); thus, DPCCH and DPDCH are time-

multiplexed and using normal QPSK modulation.

DPDCH DPCCH

DATA TFCI DATA PILOT

2560 chips

TPC

DPCCH DPDCH DPCCH

Sl t

No FBI




DATA TFCI DATA PILOT

0 21 14Downlink

DPCH

10 ms

TPCSlot

DL Dedicated Channel DCH (2/3)

• A code tree under one scrambling code is shared by several users. Normally,one scrambling code and thus only one code tree is used per sector in the BS.

• DCH SF does not vary on a frame-by-frame basis; thus, data rate is varied byrate matching operation, puncturing or repeating bits, or with DTX, where thetransmission is off during part of the slot.

• The SF is the same for all the codes with multicode transmission.

Downlink DPCH slot




TrCh A TPC TrCh B PILOTTFCI

TrCh A TPC TrCh B PILOTTFCI DTX

A full rate

A half rate

DL Dedicated Channel DCH (3/3)• UL DPDCH consists of BPSK symbols whereas DL DPDCH consists of QPSK

symbols. The bit rate in the DL DPDCH can be almost double that in the ULDPDCH.

105 kbps21024012032

45 kbps901206064

20-24 kbps42-516030128

6-12 kbps12-243015256

1-3 kbps3-6157.5512

Max. user data ratewith ½ rate coding

(approx.)

DPDCH channelbit rate range

(kbps)

Channelbit rate(kbps)

Channelsymbol rate

(kbps)

Spreading factor




2.3 Mbps5616576028804, with 3 parallelcodes

936 kbps187219209604

456 kbps9129604808

215 kbps43248024016

105 kbps21024012032

DL Multiplexing and Channel Coding Chain

CRC attachment

TrBlk concatenation/ code block

segmenation

Channel coding

1st

insertion of DTXi di i

Rate matching

TrCH 1

. . .

PhyCH segmentation

2nd (intra-frame)interleaving

PhyCH mapping

DPDCH#1 DPDCH#2 … DPDCH#N

TrCH 2

Other TrCHs




1 insertion of DTXindication

1st interleaving

Radio framesegmentation TrCH multiplexing

PhyCH segmentationOther TrCHs

CCT rCh

2nd insertion of DTXindication

Downlink Shared Channel (DSCH)

• Used for dedicated control or traffic data (bursty traffic).

• Shared by several users. Each user may allocate a DSCH for a shortperiod of time based on a particular packet scheduling algorithm.

• Support the use of fast power control, but not soft-handover.

• Use a variable spreading factor on a frame-by-frame basis so that bitrate can be varied on a frame-by-frame basis.

• Associated with a DL DPCH with the use of DPCCH. Such a DLDPCCH from TFCI provides the power control information, an

indication to which terminal to decode the DSCH and spreading




indication to which terminal to decode the DSCH and spreadingcode of the DSCH.

• Since the information of DSCH is provided from an associated DL

DPCH, the PDSCH frame may not be started before 3 slots after theend of that associated DL DPCH.



RACH Operation• First, UE sends a preamble.

• The SF of the preamble is 256 and contain a signature sequence of 16

symbols – a total length of 4096 chips.• Wait for the acknowledged with the Acquisition (AICH) from the BS.

• In case no AICH received after a period of time, the UE sends anotherpreamble with higher power.

• When AICH is received, UE sends 10 or 20 ms message part.

• The SF for the message is from 32 to 256.

BS




RACH Preamble AICH Preamble RACH Message

UE

BS

Common Packet Channel (CPCH)

• A contention-based uplink transport channel for transmission of bursty data traffic.

• Different from RACH, channel can be reserved for several framesand it uses fast power control.

• Information of CPCH is provided by

• DL DPCCH for fast power control information.

• Forward Access Channel (FACH) for higher layer DL signaling.

• CPCH operation is similar to RACH operation except that it has

Layer 1 Collision Detection (CD)




Layer 1 Collision Detection (CD).

• In RACH, one RACH message is lost, whereas in CPCH anundetected collision may lose several frames and cause extrainterference.

CPCH Operation• After receiving CPCH AICH,

• UE sends a CPCH CD preamble with the same power from anothersignature.

• If no collision after a certain time, the BS echo this signature back to theUE on the CD Indication Channel (CD-ICH).

• Then, the UE sends data over several frames with fast power control.

• The CPCH status indicator channel (CSICH) carries the status of differentCPCH information.

BS




CPCH Preamble AICH Preamble CPCH Message

CPCH CD CPCH CD-ICH

UE

Broadcast Channel (BCH)

• Downlink common transport channel.

• The physical channel of BCH is Primary Common Control PhysicalChannel (Primary CCPCH).

• BCH:

• broadcast the system and cell-specific information, e.g., randomaccess codes or slots.

• terminals must decode the broadcast channel to register to the cell.

• uses high power in order to reach all users within a cell




• uses high power in order to reach all users within a cell.

Forward Access Channel (FACH)

• Downlink common transport channel.

• It can be multiplexed with PCH to the same physical channel,Secondary CCPCH, or standalone.

• FACH:

• carry control information to UEs within a cell.• carry small amount of packet data.

• no power control.

• can have several FACHs. But the primary one must have low data




• can have several FACHs. But the primary one must have low datarate in order to be received by all terminals.

• In-band signaling is needed to inform for which user the data wasintended.

Paging Channel (PCH)

• Downlink common transport channel for transmission of paging and

notification messages, i.e., when the network wants to initiatecommunication with the terminal.

• It can be multiplexed with FACH to the same physical channel,

Secondary CCPCH, or standalone.

• The identical paging message can be sent in a single cell or hundreds

of cells. The paging message has to be reached by all the terminals

within the whole cell.

• Its transmission is associated with transmission of paging indicator in




• Its transmission is associated with transmission of paging indicator in

paging indicator channel (PICH).

Signaling Physical Channels




Common Pilot Channel (CPICH)

• Downlink channel with a fixed rate of 30 Kbps or SF of 256.

• Scrambled with the cell-specific primary scrambling code.

• Use for channel estimation reference at the terminal.

• Two types: primary and secondary CPICH

• Primary CPICH

• the measurements for the handover and cell selection / reselection.

• phase reference for SCH, primary CCPCH, AICH and etc.




p , p y ,• Secondary CPICH may be phase reference for the secondary

CCPCH.



Synchronisation Channel (SCH) – CellSearching

• Cell search using SCH has three basic steps:

• The UE searches the 256-chip primary synchronisation code,which is common to all cells and is the same in every slot. Detectpeaks in the output of the filter corresponds to the slot boundary(slot synchronisation).

• The UE seeks the largest peak secondary synchronisation code(SSC). There are 64 unique SSC sequences. Each SSC sequencehas 15 SSCs. The UE needs to know 15 successive SSCs from theS-SCH, then it can determine the code group in order to know the

frame boundary (frame synchronisation).




y y

• Each code group has 8 primary scrambling. The correct one isfound by each possible scrambling code in turn over the CPICH

of that cell.

SSC SequencesSecondary Synchronisation Code (SSC) and Code Group

:

:

61691213212313167796232

12131696167912331326231

41414916716491127115230

:

:

#14#13#12#11#10#9#8#7#6#5#4#3#2#1#0Codegroup




16 6 9 16 13 12 2 6 2 13 3 3 12 9 7 16 6 9 16 13 12

Received sequence of SSCs from S-SCHStart Frame

Primary Common Control Physical Channel(Primary CCPCH)

• Carries broadcast channel (BCH).

• Needs to be demodulated by all terminals within the cell.

• Fixed rate of 30 kbps with a spreading factor of 256.• Contains no power control information.

• Primary CCPCH is time-multiplexed with SCH; thus, it does not use

the first 256 chips. Channel bit rate is reduced to 27 kbps.




Secondary Common Control Physical Channel(Secondary CCPCH)

• Carries two transport channels: FACH and PCH, which can bemapped to the same or separate channels.

• Variable bit rate.

• Fixed spreading factor is used. Data rate may vary with DTX or ratematching parameters.

• Contains no power control information.




Physical Layer Procedures




Power Control Procedure

BS

Fast Power Control

if SIRestimate<SIRtarget,

send "power up" command

Frame reliabilty info.

SIRtarget adjustment

commands

RNC

Outer Loop Power Control

if quality<target,

increase SIRtarget

DL

UL




Power Control (PC) – (1/2)• Fast Closed Loop PC – Inner Loop PC

• Feedback information.

• Uplink PC is used for near-far problem. Downlink PC is to ensurethat there is enough power for mobiles at the cell edge.

• One PC command per slot – 1500 Hz

• Step 1 dB or 0.5 dB (1 PC command in every two slots).

• The SIR target for fast closed loop PC is set by the outer loop PC.

• Two special cases for fast closed loop PC:

• Soft handover: how to react to multiple power control commands

from several sources. At the mobile, a “power down” commandhas higher priority over “power up” command




has higher priority over power up command.

• Compressed mode: Large step size is used after a compressedframe to allow the power level to converge more quickly to the

correct value after the break.

Power Control (PC) – (2/2)• Closed Loop PC - Outer Loop PC

• Set the SIR target in order to maintain a certain frame error rate(FER). Operated at radio network controller (RNC).

• Open loop PC

• No feedback information.• Make a rough estimate of the path loss by means of a downlink

beacon signal.

•Provide a coarse initial power setting of the mobile at thebeginning of a connection.




• Apply only prior to initiating the transmission on RACH orCPCH.

Transmit Diversity (BS) – (1/2)• Antenna diversity means that the same signal is transmitted or

received via more than one antenna.

• It can create multipath diversity against fading and shadowing.

• Transmit diversity at the BS - open-loop and closed-loop.

• Open Loop Mode• No feedback information from the UE to the BS.

• BS decides the appropriate parameters for the TX diversity.

• Normally use for common channels because feedback information from a particular UE may not be good for others




information from a particular UE may not be good for othersusing the same common channel.

• Uses space-time-block-coding-based transmit diversity (STTD).

Transmit Diversity (BS) – (2/2)• Closed Loop Mode

• Feedback information from the UE to the BS to optimize thetransmission from the diversity antenna.

• Normally use for dedicated channels because they have thefeedback information bits (FBI).

• Based on FBI, the BS can adjust the phase and/or amplitude of the antennas.




Compressed Mode (1/2)• The compressed mode is needed when making measurement from

another frequency.

• The transmission and reception are halted for a short time to performmeasurements on the other frequencies.

Measurementgap




Normal

Frame

Normal

Frame

CompressedMode

Compressed Mode (2/2)• Three methods for compressed mode:

• Lowering the data rate from higher layers.• Increasing the data rate by changing the spreading factor.

• Reducing the symbol rate by puncturing at the physical layer

multiplexing chain.• More power is needed during compressed mode.

• No power control during compressed mode. Large step size is usedafter a compressed frame to allow the power level to converge morequickly to the correct value after the break.




Handover• Intra-mode handover

• Include soft handover, softer handover and hard handover.• Rely on the Ec/No measurement performed from the CPICH.

• Inter-mode handover

• Handover to the UTRA TDD mode.

• Inter-system handover

• Handover to other system, such as GSM.

• Make measurement on the frequency during compressed mode.




UTRAN Radio Interface

protocols




UTRAN Radio Interface protocol architecture.

• Transport Channels, Logical Channels, Radio Bearers.

• Radio Protocols

– Medium Access Control (MAC) protocol.– Radio Link Control (RLC) protocol.

– Packet Data Convergence (PDC) protocol.

– Broadcast/Multicast Control (BMC) protocol.

– Radio Resource Control (RRC) protocol.



UMTS Bearer services

End-toend Service

UMTS Bearer Service External Bearer

ServiceLocal Bearer

Service

UTRAService

RadioBearer Service

IuBearer Service

PhysicalBearer Service

Backbone Phys.Bearer Service

BackboneBearer Service

CNBearer Service

Radio Access Bearer Service

TE MT UTRAN CN Iu EDGE CN gateway

Radio Interfaceprotocols



Channel types in UTRAN

• Physical channel: form the physical

existence of the Uu interface between

the UE domain and access domain.

– Different kind of bandwidth allocated

for different purposes.

• RNC deals with transport channels:

carry different information flows over

the Uu interface and the physical

elements.

• Logical channels: different tasks thenetwork and the terminal should

f i diff t t f ti

RNC

Logical Channels

Transport Channels

Physical Channels

BSUE



perform in different moments of time.

– These structures are mapped to

transport channels.

Functions using logical different channels

• Network informs the UE about the radio environment. The information isprovided through the Broadcast Control Channel (BCCH)

– the code values in the cell and in the neighbouring cells, power levels …

• Paging in order to find out the actual location of the user. Th network request

is carried out in the logical channel Paging Control Channel (PCH).

• Task common for all UE residing in the cell. Common Control Channel

(CCCH). Since many users may use CCH simultaneously they are identified

by U-RNTI ( UTRAN Radio Network Temporary Identity).

• The control information of dedicated and active connection is send in

Dedicated Control Channel (DCCH).• The dedicated user traffic in DL is sent through Dedicated Traffic Channel

(DTCH)



(DTCH).

• In DL the information to all UE or a specific group of UE in the cell can be

transmitted on Common Traffic Channel (CTCH)

L3

c o n t r o l

c o n t r o l

c o n t r o l

c o n t r o l

Logical

C-plane signalling U-plane information

RLC

DCNtGC

L2/RLCRLC

RLC

RLCRLC

RLC

RLC

RLC

Duplication avoidance

UuS boundary

BMCL2/BMC

control

PDCP

PDCP L2/PDCP

DCNtGC

Radio

Bearers

RRC

UTRAN Radio Interface ProtocolArchitecture

• Transport channels: How

data is transferred

• Logical channels: what type

of data is transferred.

• Measurements reports:measurements and control

and configuration.



Logical

Channels

Transport

Channels

PHY

L2/MAC

L1

MAC

Transport Channels• Service provided by L1 to L2

(MAC). Defined how data is

transported.

• Common transport channels(where there is a need for inband

identification of the UEs when

particular UEs are addressed);

• Dedicated transport channels

(where the UEs are identified bythe physical channel, i.e. code and

frequency for FDD and code, time

slot and frequency for TDD).

Dedicated transport channel types are:

• Dedicated Channel (DCH):A channel dedicated to one UE used in uplink

or downlink.

• Common Packet Channel (CPCH):A contention based channel used for transmission of bursty

data traffic. This channel only exists in FDD mode and only

in the uplink direction. The common packet channel is shared

by the UEs in a cell and therefore, it is a common resource.The CPCH is fast power controlled.

• Forward Access Channel (FACH):

Common downlink channel without closed-loop power

control used for transmission of relatively small amount of

data.

• Downlink Shared Channel (DSCH):A downlink channel shared by several UEs carrying

dedicated control or traffic data.

• Uplink Shared Channel (USCH):

An uplink channel shared by several UEs carrying dedicated

control or traffic data, used in TDD mode only.

• Broadcast Channel (BCH):A downlink channel used for broadcast of system information

into an entire cell.



Common transport channel types are:• Random Access Channel (RACH):

A contention based uplink channel used for

transmission of relatively small amounts of

data, e.g. for initial access or non-real-time

dedicated control or traffic data.

• Paging Channel (PCH):A downlink channel used for broadcast of control information

into an entire cell allowing efficient UE sleep mode

procedures. Currently identified information types are pagingand notification. Another use could be UTRAN notification

of change of BCCH information.

Logical Channels• Service provided by MAC to higher layers.

• Defined “what type” of data is transferred.

• Control Channels:

– Broadcast Control Channel (BCCH) (DL)

– Paging Control Channel (PCCH) (DL)MAC

RLC

Logical Channels

– Dedicated Control Channel (DCCH) (UL&DL): a point-to-point bidirectional channel that

transmits dedicated control information between a UE and the network. Established duringRRC connection establishment procedure.

– Common Control Channel (CCCH) (UL&DL): a bidirectional channel for transmitting

control information between a UE and the network.

• Traffic Channels:

– Dedicated Traffic Channels (DTCH) (UL&DL)– Common Traffic Channels (CTCH) (DL)



Mapping between logical and transportchannels (Uplink)

DCHCPCHRACH

CCCHDCCHDTCH Logical

Channels

Transport Channels

Uplink

Examples of carried data:• RACH: control information from UE to

the UTRAN.

– Connection set-up request.

– Small amounts of packet data.

• DCH: dedicated traffic and control

information. It may contain several

DTCH. (Similar to the one in DL)

• CPCH: a common transport channel for

packet data transmission. (Extention of RACH)



PRACH DPDCHDCPCH DPCCH

Physical Channels

Mapping between logical and transportchannels (Downlink)

BCH DSCHFACHPCH DCH

PCCHDCCHDTCHCTCHBCCH CCCHLogical

Channels

Transport

Channels

Downlink Examples of carried data:• BCH: UTRA specific information

– random access codes, access slot

information, …

• PCH: Paging information. Network wishes to initiate connection.

• FACH: Control information to the UE

known to be in the cell.

– Response to the random access

message.

• DCH: dedicated traffic and control

information It may contain several



Physical Channels

DPCCHDPDCHPDSCHP-CCPCHS-CCPCH

information. It may contain several

DTCH.

• DSCH: Dedicated user information for

packet traffic.

Radio Bearers

• Service provided by

RLC/PDCP/BMC to higher layers.

• Defined by:

– RLC/PDCP/BMC parameters.

– Transport channel parameters.

– Physical channel parameters??

– Mapping between Radio

bearer(s) logical channels and

transport channels.RLC

RRC

PDCP

BMC

Signalling Radio Bearers

U-Plane Radio Bearers



Medium Access Control protocol functions

• Mapping between logical channels and transportchannels.

• Selection of appropriate Transport Format for each

Transport Channel depending on instantaneous

source rate.

• Priority handling between data flows of one UE.• Priority handling between UEs by means of

dynamic scheduling.

• Identification of UEs on common transport

channels.

PHY

MAC

RLC

RRC

PDCP

BMC

Logical Channels

Transport Channels

L3

L2

L1

control plane user-plane



• Multiplexing/demultiplexing of upper layer PDUs into/from transport block setsdelivered to/from the physical layer on dedicated transport channels.

• Traffic volume measurement.



• Transport Channel type switching.

• Ciphering for transparent mode RLC.

• Access Service Class selection for RACH and CPCH transmission.

MAC layer logical architecture

BCH

PCCH DTCH

MAC-Control

MAC-b MAC-c/shMAC-d

DTCHDCCHBCCH CTCHCCCHBCCH

DCHDSCHCPCHRACHFACHPCH DCH

Logical

Channels

Transport Channels

Services provided to upper layers

• Data transfer: This service provides unacknowledged transfer of MAC SDUs

between peer MAC entities without data segmentation



between peer MAC entities without data segmentation.

• Reallocation of radio resources and MAC parameters: This service

performs on request of RRC execution of radio resource reallocation and

change of MAC parameters.

• Reporting of measurements: Local measurements are reported to RRC.

MAC PDU Format

• MAC header consist of:

• Target Channel Type field (TCFT): a flag that

provides identification of the logical channel

class on FACH and RACH transport channels.

MAC SDUC/TUE-Id

MAC header MAC SDU

TCTF UE-Idtype

MAC PDU

(BCCH, CCCH, CTCH, SHCCH or dedicated logical channel information).

• C/T field: provides identification of the logical channel instance when multiplelogical channels are carried on the same transport channel.

• UE-Id field: provides an identifier of the UE on common transport channels.– UTRAN Radio Network Temporary Identity (U-RNTI) may be used in the MAC header

of DCCH when mapped onto common transport channels in downlink direction; the U-

RNTI is never used in uplink direction;– Cell Radio Network Temporary Identity (C-RNTI) is used on DTCH and DCCH in

uplink, and may be used on DCCH in downlink and is used on DTCH in downlink when

d h l



mapped onto common transport channels;

– the UE id to be used by MAC is configured through the MAC control SAP.

• UE-Id Type field: is needed to ensure correct decoding of the UE-Id field in MACHeaders

MAC c/sh

MAC-c/sh

MAC – Control

to MAC –d

FACHCPCH ( FDD only )FACH

CTCHCCCH BCCHSHCCH (TDD only)PCCH

PCH

UL: TF selection

USCHTDD only

DSCH RACH

Scheduling/PriorityHandling (1)

add/read UE Id

DSCH USCHTDD only

TFCselection

TCTF MUX

ASCselection

ASCselection (2)

Note 1: Scheduling /Priority handling is applicable for CPCH.Note 2: In case of CPCH, ASC selection may be applicable for AP preamble.

CTCH

MAC-c/sh

to MAC – d

MAC – ControlCCCHBCCH SH CCH

(TDDonly)

PCCH

Flow Control

MAC-c/sh / MAC-d

TCTF MUX / UE Id MUX

S h d li / P i it H dli / D

TCTF MUX: this function represents the handling (insertion for uplink

channels and detection and deletion for downlink channels) of the TCTF

field in the MAC header, and the respective mapping between logical and

transport channels.The TCTF field indicates the common logical channel

type, or if a dedicated logical channel is used;

add/read UE Id:• the UE Id is added for CPCH and RACH transmissions

• the UE Id, when present, identifies data to this UE.

UL: TF selection: in the uplink, the possibility of transport format

selection exists. In case of CPCH transmission, a TF is selected based on

TF availability determined from status information on the CSICH;

ASC selection: For RACH, MAC indicates the ASC associated with the

PDU to the physical layer. For CPCH, MAC may indicate the ASC

associated with the PDU to the Physical Layer. This is to ensure that

RACH and CPCH messages associated with a given Access Service Class

(ASC) are sent on the appropriate signature(s) and time slot(s). MAC also

applies the appropriate back-off parameter(s) associated with the given

ASC. When sending an RRC CONNECTION REQUEST message, RRC

will determine the ASC; in all other cases MAC selects the ASC;

scheduling /priority handling: this functionality is used to transmit

UE side MAC-c/sh details



FACH RACH CPCH(FDD only )

FACHPCH

TFC selection

DSCH USCHTDD only

USCHTDD only

DSCH

DL: codeallocation

Scheduling / Priority Handling/ Demux

TFC selection

the information received from MAC-d on RACH and CPCH based on

logical channel priorities. This function is related to TF selection.

TFC selection: transport format and transport format combinationselection according to the transport format combination set (or transport

format combination subset) configured by RRC is performed,UTRAN side MAC-c/sh details

MAC-d DCCH DTCH DTCH

DCH DCH

MAC-d

to MAC-c/sh

Ciphering

MAC Control

UL: TFC selection

C/T MUX

C/T MUX

Deciphering

Transport Channel Type Switching

Note 1: For DCH and DSCH different scheduling mechanism apply

Note 2: Ciphering is performed in MAC-d only for transparent RLC mode

DCCH

UE

DTCH DTCH

MAC-d

MAC-Control

C/TMUX

Transport Channel Type Switching

Fl C t l

C/T MUX / Priority

setting

Deciphering

Transport Channel type switching: performed based on

decision taken by RRC. This is related to a change of radio resources.

If requested by RRC, MAC shall switch the mapping of one

designated logical channel between common and dedicated transport

channels.C/T MUX: The C/T MUX is used when multiplexing of several

dedicated logical channels onto one transport channel is used. An

unambiguous identification of the logical channel is included.

Ciphering: Ciphering for transparent mode data to be ciphered is

performed in MAC-d.

Deciphering: Deciphering for ciphered transparent mode data is

performed in MAC-d.

UL TFC selection: Transport format and transport format

combination selection according to the transport format combination

set (or transport format combination subset) configured by RRC is

performed.

DL Scheduling/Priority handling: in the downlink,

scheduling and priority handling of transport channels is performed

within the allowed transport format combinations of the TFCS

UE side MAC-d details



DCH DCH

MAC dto MAC-c/sh

MUX

DL scheduling/ priority handling

Ciphering

Flow ControlMAC – c/sh /

MAC-dassigned by the RRC.

Flow Control: a flow control function exists toward MAC-c/sh

to limit buffering between MAC-d and MAC-c/sh entities. Thisfunction is intended to limit layer 2 signalling latency and reduce

discarded and retransmitted data as a result of FACH or DSCH

congestion. UTRAN side MAC-d details

Radio Link Control protocol

• Segmentation and reassembly.

• Concatenation.• Padding.

• Transfer of user data.

• Error correction.

• In-sequence delivery of upper layer

PDUs.• Duplicate detection.

• Flow control.

• Sequence number check.

• Protocol error detection and recovery.

• Ciphering.

• SDU discard.PHY

MAC

RLC

RRC

PDCP

BMC

Logical Channels

Transport Channels

L3

L2

L1

control plane user-plane





RLC logical architecture

• Provides segmentation/reassembly (payload units, PU) and retransmission

service for both user(Radio Bearer) and control data (Signalling Radio bearer).

• Transparent mode (Tr): no overhead is added to higher layer data.

• Unacknowledged mode (UM): no retransmission protocol is used and data

Transmittingtransparent

entity

Receivingtransparent

entity

Acknowledgedmode entity

Transmittingunacknowledged

entity

Receivingunacknowledged

entity

Tr-SAP AM-SAP

DTCH/DCCH CCCH/CTCH/

DTCH/DCCH

BCCH/PCCH/

CCCH/DCCH/DTCH

UM-SAP

RLC-Control



Unacknowledged mode (UM): no retransmission protocol is used and data

delivery is not guaranteed.

• Acknowledged mode (AM): Automatic Repeat reQuest (ARQ) mechanism isused for error correction.

RLC Services provided to upper layers

• Transparent data transfer Service:

• The following functions are needed to

support transparent data transfer:– Segmentation and reassembly.

– Transfer of user data.

– SDU discard.

• Unacknowledged data transfer

Service:• The following functions are needed to

support unacknowledged data transfer:– Segmentation and reassembly.

– Concatenation.

– Padding.– Transfer of user data.

– Ciphering.

– Sequence number check

• Acknowledged data transfer Service:

• The following functions are needed to

support acknowledged data transfer:– Segmentation and reassembly.

– Concatenation.

– Padding.

– Transfer of user data.

– Error correction.– In-sequence delivery of upper layer

PDUs.

– Duplicate detection.

– Flow Control.

– Protocol error detection and recovery.

– Ciphering.

– SDU discard.

• Maintenance of QoS as defined by



Sequence number check.

– SDU discard. upper layers.

• Notification of unrecoverable errors.

RLC transparent mode (TM) entity (1)

Transmitting

TM- RLC

entityTransmission

buffer

Segmentation

TM-SAP

CCCH/DCCH/DTCH/SHCCH – UE

BCCH/PCCH/DCCH/DTCH – UTRAN

Receiving

TM- RLC

entity

Reception

buffer

Reassembly

TM-SAP

Radio Interface (Uu)

CCCH/DCCH/DTCH/SHCCH – UTRAN

BCCH/PCCH/DCCH/DTCH – UE

UE/UTRAN UTRAN/UEReceiving TM-RLC entity:

• The receiving TM-RLC entity receivesTMD PDUs through the configured

logical channels from the lower layer.

If segmentation is configured by upper

layers, all TMD PDUs received within

one TTI are reassembled to form theRLC SDU.

• If segmentation is not configured by

upper layers, each TMD PDU is treated

as a RLC SDU.

• The receiving TM RLC entity deliversRLC SDUs to upper layers through the

TM-SAP.



RLC transparent mode (TM) entity (2)

Transmitting TM-RLC entity:• The transmitting TM-RLC entity receives RLC SDUs from upper layers through

the TM-SAP.

• All received RLC SDUs must be of a length that is a multiple of one of the valid

TMD PDU lengths.

• If segmentation has been configured by upper layers and a RLC SDU is larger

than the TMD PDU size used by the lower layer for that TTI, the transmitting

TM RLC entity segments RLC SDUs to fit the TMD PDUs size without adding

RLC headers. All the TMD PDUs carrying one RLC SDU are sent in the same

TTI, and no segment from another RLC SDU are sent in this TTI.

• If segmentation has not been configured by upper layers, then more than one

RLC SDU can be sent in one TTI by placing one RLC SDU in one TMD PDU.All TMD PDUs in one TTI must be of equal length.

• When the processing of a RLC SDU is complete, the resulting one or more TMD

PDU(s) are/is submitted to the lower layer through either a BCCH, DCCH,



PDU(s) are/is submitted to the lower layer through either a BCCH, DCCH,

PCCH, CCCH, SHCCH or a DTCH logical channel.

RLC unacknowledged mode entity

Transmittin

g

UM RLC

entity

Transmission

buffer

UM-SAP

Receiving

UM RLC

entity

Reception

buffer

UM-SAP

Radio Interface (Uu)

Segmentation &

Concatenation

Ciphering

Add RLC header

Reassembly

Deciphering

Remove RLC

header

CCH/DTCH – UE

CCH/SHCCH/DCCH/DTCH/CTCH – UTRAN

DCCH/DTCH – UTRAN

CCCH/SHCCH/DCCH/DTCH/CTCH – UE

UE/UTRAN UTRAN/UEReceiving UM-RLC entity:

• The receiving UM-RLC entity receives UMD

PDUs through the configured logical

channels from the lower layer.

• The receiving UM RLC entity deciphers (if

ciphering is configured and started) the

received UMD PDUs (except for the UMDPDU header). It removes RLC headers from

received UMD PDUs, and reassembles RLC

SDUs (if segmentation and/or concatenation

has been performed by the transmitting UM

RLC entity).• RLC SDUs are delivered by the receiving

UM RLC entity to the upper layers through

the UM-SAP



the UM SAP.

RLC unacknowledged mode entity (2)

Transmitting UM-RLC entity:• The transmitting UM-RLC entity receives RLC SDUs from upper layers

through the UM-SAP.

• The transmitting UM RLC entity segments the RLC SDU into UMD PDUs of

appropriate size, if the RLC SDU is larger than the length of available space in

the UMD PDU. The UMD PDU may contain segmented and/or concatenated

RLC SDUs. UMD PDU may also contain padding to ensure that it is of a valid

length. Length Indicators are used to define boundaries between RLC SDUs

within UMD PDUs. Length Indicators are also used to define whether Padding

is included in the UMD PDU.

• If ciphering is configured and started, an UMD PDU is ciphered (except for the

UMD PDU header) before it is submitted to the lower layer.• The transmitting UM RLC entity submits UMD PDUs to the lower layer

through either a CCCH, SHCCH, DCCH, CTCH or a DTCH logical channel.



RLC acknowledged mode entity (1)

Transmission

buffer

Retransmission

buffer &

management

MUX

Set fields in PDU Header (e.g. set poll

bits) & piggybacked STATUS PDU

RLC Control Unit

R e c e i v e d

a c k n o wl e d g e m e n t s

Acknowledgements

DCCH/

DTCH*

AM-SAP

DCCH/

DTCH**

DCCH/

DTCH**

AM RLC entity

Demux/Routing

DCCH/

DTCH*

DCCH/

DTCH**

DCCH/

DTCH**

Reception buffer

& Retransmissionmanagement

Receiving side

Segmentation/Concatenation

Ciphering (only for AMD PDU)

Add RLC header

Reassembly

Deciphering

Remove RLC header & Extract

Piggybacked information

Piggybacked status

Optional

Transmitting side

UE/UTRAN

• The receiving side of the AM-RLC entity

receives AMD and Control PDUs through the

configured logical channels from the lower

layer.

• AMD PDUs are routed to the Deciphering Unit

and then delivered to the Reception buffer.

• The AMD PDUs are placed in the Reception

buffer until a complete RLC SDU has been

received. The Receiver acknowledges

successful reception or requests retransmission

of the missing AMD PDUs by sending one or

more STATUS PDUs to the AM RLC peer

entity, through its transmitting side.• The associated AMD PDUs are reassembled by the Reassembly Unit and delivered

to upper layers through the AM-SAP.

• RESET and RESET ACK PDUs are delivered to the RLC Control Unit for



• RESET and RESET ACK PDUs are delivered to the RLC Control Unit for

processing. If a response to the peer AM RLC entity is needed, an appropriate

Control PDU is delivered, by the RLC Control Unit to the transmitting side of theAM RLC entity.

RLC acknowledged mode entity (2)• The transmitting side of the AM-RLC entity receives RLC SDUs from upper layers

through the AM-SAP.

• RLC SDUs are segmented and/or concatenated into AMD PDUs of a fixed length.– The segmentation is performed if the received RLC SDU is larger than the length of available

space in the AMD PDU.

– The PDU size is set during AM-RLC establishment.

– The packets could be segmented, concatenated, padded.

– Boundaries between the packets are indicated by a length indicator.

• After the segmentation and/or concatenation are performed, the AMD PDUs are placed in the

Retransmission buffer at the MUX.

• AMD PDUs buffered in the Retransmission buffer are deleted or retransmitted.• The MUX multiplexes AMD PDUs from the Retransmission buffer that need to be

retransmitted, and the newly generated AMD PDUs delivered from the

Segmentation/Concatenation function.

• The PDUs are delivered to the function that completes the AMD PDU header and

potentially replaces padding with piggybacked status information. A PiggybackedSTATUS PDUs can be of variable size in order to match the amount of free space in the

AMD PDU.

Th i h i (if fi d) i th li d t th AMD PDU



• The ciphering (if configured) is then applied to the AMD PDUs.– The AMD PDU header is not ciphered.

– Control PDUs (i.e. STATUS PDU, RESET PDU, and RESET ACK PDU) are not ciphered.

• AMD PDUs are submitted to either one or two DCCH or DTCH logical channels.

Packet Data Convergence Protocol (PDCP)

• The Packet Data Convergence Protocol shall perform the following functions:– Header compression and decompression of IP data streams (e.g., TCP/IP and

RTP/UDP/IP headers for IPv4 and IPv6) at the transmitting and receiving entity,respectively. (In Release 99 compression accordingly RFC 2507).

– Transfer of user data. This function is used for conveyance of data between users of

PDCP services.

M i t f PDCP b f di b th t fi d t

Headercomp. entityAlg. Type 1


UM-SAP AM-SAP Tr-SAP

PDCP-Control




PDUnumbering

PDUnumbering

PDCP entity PDCP entity PDCP entity

RLC SAPs

PDPC SAPs (Radio Bearers)

PDCP-SDU

RLC-SDU



– Maintenance of PDCP sequence numbers for radio bearers that are configured to

support lossless SRNS Relocation.

• PDCP uses the services provided by the Radio Link Control (RLC) sublayer.

Broadcast Multicast Control (BMC)

• Storage of Cell Broadcast

Messages.

• Traffic volume monitoring and

radio resource request for CBS.

• Scheduling of BMC messages.

• Transmission of BMC messagesto UE.

• Delivery of Cell Broadcast

messages to upper layer.

BMC entity

BMC-Control

UM-SAP

RLC SAPs

BMC SAP



Radio Resource Control (RRC)Used for setting up, reconfigure and reestablish radio bearers.• Cell Broadcast Service (CBS) control.

• Initial cell selection and cell re-selection.

• Paging.• Broadcast of information:

– related to the non-access stratum (Core Network).

– related to the access stratum.

• Establishment, maintenance and release

– of an RRC connection between the UE and UTRAN.– of Radio Bearers.

• Assignment, reconfiguration and release of radio resources for the RRC connection.

• Control of requested QoS.

• UE measurement reporting and control of the reporting.

• RRC message integrity protection.• Arbitration of radio resources on uplink DCH.

• Slow Dynamic Channel Allocation (DCA) (TDD mode).

• Timing advance (TDD mode).



Timing advance (TDD mode).

• RRC connection mobility functions (RNC relocation).

• Outer loop power control.• Control of ciphering.

RRC logical architecture

• Dedicated Control Functional

Entity (DCFE): Handles functions

and signalling specific to UE. One

DCFE entity for each UE.

• Paging and Notification control

Functional Entity (PNFE): paging

of idle mode UE. At least onePNFE in the RNC for each cell.

• Broadcasting Control Functional

Entity (BCFE): handles the

broadcasting of system

information. There is at least oneBCFE for each cell in the RNC.UM-SAPAM-SAP Tr-SAP

BMC-Control

SAP

DCFE PNFE BCFE

PDCP-Control

SAP

RLC-Control

SAP

MAC-Control

SAP

l1-ControlSAP

AM-SAP AM-SAP

Message Routing

RLC SAPs



RRC states and state transitionsincluding GSM

Establish RRCConnection

Release RRC

Connection

UTRA RRC Connected Mode

UTRA:Inter-RATHandover

GSM:Handover

Establish RRCConnection

Release RRC

Connection

URA_PCH CELL_PCHGSM

Connected

Mode

Establish RR

Connection

Release RR

Connection

Idle Mode

Camping on a UTRAN cell1 Camping on a GSM / GPRS cell1

GPRS Packet Idle Mode1

GPRS

Packet

TransferMode

Initiation of

temporary

block flow

Release of

temporary

block flow

Cell reselection

CELL_DCH

out of service

in service

CELL_FACH

out of service

in service

out of service

in service



RRC service states• Idle Mode:

– After UE is switched on it will camp in the a suitable cell. After camping:

– User is able to send and receive system and cell broadcasting information.

– In the idle mode until it transmits a request to establish RRC connection.

• Cell_DCH

– Entered from Idle Mode or by establishing a DCH from the Cell_FACH state.

– DPCH and physical downlink shared channel (PDSCH) is allocated to UE.

– UE is in this mode until explicit signalling for Cell_FACH.

• Cell_FACH– No dedicated channel allocated. Data transmitted through RACH and FACH.

– UE listens BCH.

– Cell reselection is performed (RNC is informed).

• Cell_PCH

– UE known at a cell level but can be reached via PCH.

– Usel listens BCH, some terminals also BMC.

– In case of Cell reselection automatically moved to Cell_FACH state.



• URA_PCH

– UE executes the cell update procedure only if the UTRAN Registration Area is changed.

– DCCH can not be used in this state, all the activities initiated by the network through the

PCCH or RACH.

WCDMA network planning




Purpose of planning process.

• Peculiarities of 3G network.

• Dimensioning.

• Soft capacity.

• Capacity and coverage planning.• Dynamic simulations.



Planning• Planning should meet current standards and demands and also comply with future

requirements.

• Uncertainty of future traffic growth and service needs.

• High bit rate services require knowledge of coverage and capacity enhancements methods.

• Real constraints

– Coexistence and co-operation of 2G and 3G for old operators.

– Environmental constraints for new operators.

• Network planning depends not only on the coverage but also on load.

Objectives of Radio network planning• Capacity:

– To support the subscriber traffic with sufficiently low blocking and delay.

• Coverage:

– To obtain the ability of the network ensure the availability of the service in the entire service area.

• Quality:

Li ki th it d th d till id th i d Q S



– Linking the capacity and the coverage and still provide the required QoS.

• Costs:– To enable an economical network implementation when the service is established and a controlled

network expansion during the life cycle of the network.

What is newMultiservice environment:

• Highly sophisticated radio interface.

– Bit rates from 8 kbit/s to 2 Mbit/s,also variable rate.

• Cell coverage and service design for

multiple services:

– different bit rate

– different QoS requirements.

• Various radio link coding/throughput

adaptation schemes.

• Interference averaging mechanisms:

– need for maximum isolation betweencells.

• “Best effort” provision of packet data.

• Intralayer handovers

Air interface:

• Capacity and coverage coupled.

• Fast power control.• Planning a soft handover overhead.

• Cell dominance and isolation

• Vulnerability to external interference

2G and 3G:

• Coexistence of 2G 3G sites.

• Handover between 2G and 3G

systems.

• Service continuity between 2G and

3G.



Radio network planning process

DIMENSIONING

NetworkConfiguration

andDimensioning

Requirementsand strategyfor coverage,

quality, andcapacity,

per services

CoveragePlanning andSite Selection

Propagation

measurementsCoveragePrediction

Site

acquisitionCovergeoptimisation

Capacity Requirements

Traffic distributionService distributionAllowed blocking/queuingSystem features

Externernal InterfaceAnalysis

IdentificationAdaptation

Parameter

Planning

Network

Optimisation

Handover

stategies

Area/Cell

specific

OtherRRM

Maximumloading

Statisticaleprformance

analysis

Surveymeasurements

QualityEfficiency

Availability

O & MPLANNING and IMPLEMENTATION



Using information from 2G networks New issues in 3G planning

Capacity estimation in a CDMAcell

P

CIR K k j

k

K

j

N

P

CIR K k j

k

K

j

N

P

CIR k j

k

K

j

N

P P P

P P P

P P P

j

j

K

j

0 0

0

1 0

0

0 0

1 0 0

1

1

1

0 0 0

1

1

1

0 0 1 0

1

1

1

0

0

0

,

,

,

, , ,

, , ,

, , ,

...

...

...



k j 11

Impact of uncertainties to the capacity inthe cell• Location of users in the cell

– depending where users are located in

the cell they get different interference

from other cells and capacity varies

0 100 200 300 400 500 600 700 800 900 1000−80

−60

−40

−20

0

20

40

P s , i

[ d B m ]

Number of users per cell = 50

min distanceuniform distributionmax distance

0 100 200 300 400 500 600 700 800 900 10006

6.5

7

7.5

8x 10

−3

Distance from BS [m]

C I R

• Speed of users

– target CIR function of speed

– conditions in the cell vary with users movements• Data rates

– n times voice datarate correspon

ds to n users transmitting from that location. (“high

nonuniformity”)

0 .31 .2

Soft Capacity

• surrounding cells lightly loaded

• less interference to the heavily loaded cell



y

• capacity to heavily loaded cell can beincreased

Conditions for planningConditions

• capacity not constant

• separate analysis for UL/DL

• joint coverage/capacity analysis

• HO areas and levels affect directly system

capacity

• basic shared resource is power

Objective parameters

• coverage

• capacity (blocking)

• good link quality (BER, FER)

• throughput delay, for packet services

Methods

• preplanned during network planning process

• real time radio resource management

• real time power control

Network planningResource reservation for handling expected traffic without congestion.

– load per cell/sector, handover areas

Sets allowable “power budget” available for services

– load higher than expected

– load “badly” distributed

– implements statistical multiplexing

power



p p g

Estimates average power/load, variationsof it are taken care in run time by RRM

– maximal allowed load versus average load load

Planning methods

• Preparation phase.

– Defining coverage and capacity objectives.

– Selection of network planning strategies.

– Initial design and operation parameters.

• Initial dimensioning.

– First and most rapid evaluation of the network elements count and capacity of these elements.

– Offered traffic estimation.

– Joint capacity coverage estimation.

• Detailed planning.

– Detailed coverage capacity estimation.

– Iterative coverage analysis.

– Planning for codes and powers.

• Optimisation.– Setting the parameters

• Soft handover.

• Power control.

• Verification of the static simulator with the dynamic simulator



• Verification of the static simulator with the dynamic simulator.

– Test of the static simulator with simulator where the users actual movements are modelled.

A strategy for dimensioningPlan for adequate load and number of sites.

• Enable optimised site selection.

• Avoid adding new sites too soon.

• Allow better utilisation of spectrum.

Recommended load factor 30- 70 %

1. Initial phase:Acquire only part of sites and use coverage

extension techniques to fill the gap.

Network expansion:• Add more sites.

• Add more sectors / carriers to existing sites.

2. Initial phase:Acquire sites but install part of BSS equipment.

• Allow traffic concentration at RNC level.

• Install less sectors and and less BS.

Network expansion:• Add more BS/HW/sectors/carriers.

2G operator:Re-using the infrastructure (Lover cost):+ Transmission network.

+ Sites (masts, buildings, power supplies,…).

Green-field operator:Radio network implementation from

scratch.

Renting infrastructure from other operators.+ Less limitations easier implementations



Challenges- Sufficient coverage for all services.

- Intersystem handover not seamless.

+ Less limitations easier implementations

- Higher Cost.

Dimensioning• Initial planning

– first rapid evaluation of the network element count as well as associated

capacity of those elements.

• Radio access

– Estimate the sites density.

– Site configuration.

• Activities

– Link budget and coverage analysis.– Capacity estimation.

– Estimation of the BS hardware and sites, RNCs and equipments at

different interfaces. Estimation of Iur,Iub,Iu transmission capacities.

– Cell size estimation.

• Needed

– Service distribution.

– Traffic density.

ffi h i i



– Traffic growth estimation.

– QoS estimation.

Dimensioning process

Link Budget calculationmax. allowed path loss

Cell range calclationmax. cell range in each area

Capacity estimationnr. sites, total traffic

Equipmentrequirement

Load Factorcalculation

Equipment specific input- ms power class- ms sensitivity...

Environment specific input- propagation environment- Antennae higth

...

Service specific input- blocking rate- traffic peak

...

Radio link specific input:- Data rate- Eb/Io

...Interference

margin

max. traffic percomputing unit



nr BS, equipments

WCDMA cell range

• Estimation of the maximum allowed propagation loss in a cell.

• Radio Link budget calculation.

– Summing together gains and degradations in radio path.

– Interference margin.– Slow fading margin.

– Power control headroom.

• After choosing the cell range the coverage area can be calculated using

propagation models

– Okumura-Hata, Walfisch-Ikegami, … .

• The coverage area for one cell is a hexagonal configuration estimated from:

coverage area.

maximum cell range, accounting the fact that sectored cells are not hexagonal.

Constant accounting for the sectors.

2S K r = ⋅

S

K r

Site configuration Omni 2-sectored 3-sectored 6-sectored



Value of K 2.6 1.3 1.95 2.6

12.2 kbps voice service (120 km/h, in car)

Transmitter (mobile)

Max. mobile transmission power [W] 0.125

As above in [dBm] 21 a

Mobile antenna gain [dBi] 0 b

Cable/Body loss [dB] 3 c

Equivalent Isotropic Radiated Power 18 d=a+b-c

Receiver BS

Thermal noise density [dBm/Hz] -174 e

Base station recever noise figure [dB 5 f

Receiver noise density [dBm/Hz] -169 g=e+f

Receiver noise power [dBm] -103.2 h=g+10*log10(3840000)

Interference margin [dB] 3 i

Receiver interference power [dBm] -103.2 j=10*log10(10 (̂(h+1)/10)-10 (̂h/1

Total effective noise + interference [ -100.2 k=10*log10(10 (̂h/10)+10 (̂j/10))

Processing gain [dB] 25 l=10*log10(3840/12.2)

Required Eb/No [dB] 5 m

Receiver sensitivity [dBm] -120.2 n=m-l+k

Base station antenna gain [dBi] 18 o

Cable loss in the base station [dB] 2 p

Fast fading margin [dB] 0 qMax. path loss [dB] 154.2 r=d-n+o-p-q

Coverage probability [%] 95

Log normal fading constant [dB] 7

Propagation model exponent 3.52

Log normal fading margin [dB] 7.3 s

Example of a

WCDMA RLB



Soft handover gain [dB], multi-cell 3 tIn-car loss [dB] 8 u

Allowed propagation loss for cell ran 141.9 v=r-s+t-u

Load factor uplink

, 1, ,k k k n

k own k oth k own k own

P PW W k K

R I P I N R I P i I N

ρ

= ≥ = − + + − + ⋅ +

( )1 1k k k k k k k own

R R RP i I N

W W W

ρ ρ ρ + = + +

( )1 1

1 , 1, ,

1 1k own

k k k k

P i I N k K W W

R R ρ ρ

= + ⋅ + =+ +

⋅ ⋅

Interference degradation margin: describes the amount of increase of the interferencedue to the multiple access. It is reserved in the link budget.

Can be calculated as the noise rise: the ratio of the total received power to the noise

power: 1_

1

total

N UL

I Noise rise

P η

= =

− ULη Where is load factor.

Assume that MS k use s bit rate , target is and WCDMA chip rate is .k R0

b E

I k ρ W

The inequality must be hold for all the users and ca be solved for minimum received

signal power (sensitivity) for all the users.



( )

( )

( )

( )

1 1 1 1

1

1

1

1 11

1 1

11

1

1

11 1

1

n n n

n

n

n

K K K N

k k

k k k k

k k k k

K

k

K k k

k

k

K

k

k k

P i P N W W

R R

N iW

RP i

iW

R

ρ ρ

ρ

ρ

= = = =

=

=

=

= + ⋅ + ⋅ + + ⋅ ⋅

⋅ + +

⋅ ⇒ ⋅ + =

− + +

⋅

∑ ∑ ∑ ∑

∑

∑∑

1

nK

own k

k

I P=

= ∑

Load factor uplink (2)Interference in the own cell is calculated by summing over all the users signal powers in

the cell.



Load factor uplink (3)

( )1

11

1

nK

UL

k

k k

iW

R

η

ρ =

= ++

⋅

∑Uplink loading is defined as:

By including also effect of sectorisation (sectorisation gain , number of sectors ),

and voice activity .

1

11

1

nK

s

UL k

k

k k

N i

W

R

η ν ξ

ρ

=

= + +

⋅

∑

ξ s N

ν

0 100 200 300 400 500 600 7000

2

4

6

8

10

12

14

16

18

20

N o i s e r i s e [ d B ]

i=0i=0.65



Noise rise in uplink

0 100 200 300 400 500 600 700

load [ kbit/s ]

Load Factor Downlink

( )1 1,

1

I N

i i i mi DL i

i n nin m

R LP

W LP

ρ ν η α

= =≠

= − + ∑ ∑

mi LP

1,

N mi DL

n nin m

LPi LP=

≠

= ∑

( )1010log 1 L η = −

The interference degradation margin in downlink to be taken into account in the link

budget due to a certain loading is

The downlink loading is estimated based on

is a link loss from the serving BS to MS ,

is the link loss from another BS , to MS ,

is the transmit requirement for MS , including soft HO combining gain anthe average power rise due to the fast power control,

number of BS,

number of connections in a sector,

orthogonality factor.

N

I

0

b E

I i ρ

iα

ni LP

The other to own cell interference in downlink

The total BS transmit power estimation considers multiple communication links with



average from the serving BS.( )mi LP

Receiver sensitivity estimation

• In RLB the receiver noise level over WCDMA carrier is calculated.

• The required contains the processing gain and the loss due to the loading.• The required signal power:

signal power,

background noise.

• In some cases the noise/interference level is further corrected by applying a

term that accounts for man made noise.

0r P SNR N W = ⋅ ⋅

0 N W ⋅r P

( )1 RSNR

W ρ

η = ⋅ ⋅ −



Spectrum efficiencyUplink

• rx_Eb/Io is a function of required BER target and multipath channel model.

• Macro diversity combining gain can be seen as having lower rx_Eb/Io when

the MS is having links with multiple cells.

• Inter cell interference i is a function of antennae pattern, sector configuration

and path loss index.

Downlink

• tx_Eb/Io is function of required BER target and multipath channel model.

• Macro diversity combining gain can be seen as having lover tx_Eb/Io when

MS is having radio links with multiple cells.

• Orthogonality factor is a function of the multipath channel model at the given

location.• Planners have to select the sites so that the other to own cell interference i is

minimised.

– Cell should cover only what is suppose to cover.



Coverage improvement• Coverage limited by UL due to the lower transmit power of MS.

• Adding more sites.

• Higher gain antennas.

• RX diversity methods.• Better RX -sensitivity.

• Antennae bearing and tilting.

• Multi-user detection.

Capacity improvement• DL capacity is considered more important than UL, asymmetric traffic.

– Due to the less multipath microcell capacity better than macrocell.

• Adding frequencies.• Adding cells.

• Sectorisation.

• Transmit diversity.



• Lower bit rate codecs.• Multibeam antennas.

RNC Dimensioning• The whole network area divided into regions each handled by a single RNC.

• RNC dimensioning: provide the number of RNCs needed to support the estimated traffic.

• For uniform load distribution the amount of RNCs:

RNC limited by:

• Maximum number of cells:

number of cells in the area to be dimensioned, maximum number of cells, margin used to back off from the maximum capacity.

• Maximum number of BS: number of BS in the area to be dimensioned, maximum number of BSs that can be

connected to one RNC, margin used to back off from the maximum capacity.

• Maximum Iub throughput:

maximum Iub capacity, margin used to back off from it, the expected number

simultaneously active subscribers.

1

numCellsnumRNCs

cellsRNC fillrate=

⋅

3

voiceTP CSdataTP PSdataTPnumRNCs

tpRNC fillrate

+ +=

⋅

2

numBTSs

numRNCs btsRNC fillrate= ⋅

( )

( )

( )

1

1

/ 1

voice voice

CSdata CSdata

PSdata

voiceTP voiceErl bitrte SHO

CSdataTP CSdataErl bitrate SHO

PSdtaTP avePSdata PSoverhead SHO

= ⋅ +

= ⋅ +

= ⋅ +



• Amount of type of interfaces (STm-1, E1).

RNC dimensioning (2)

• Supported traffic (upper limit of RNC processing).

– Planned equipment capacity of the network, upper limit.

– For data services each cell should be planned for maximum capacity

• too much capacity across the network. RNC is able to offer maximum capacity in every

cell but that is highly un-probable demand.

• Required traffic (lower limit of RNC processing).

– Actual traffic need in the network, base on the operator prediction.

– RNC can support mean traffic demand.

– No room for dynamic variations.• RNC transmission interface Iub.

– For N sites the total capacity for the Iub transmission must be greater than N times

the capacity of a site.

• RNC blocking principle.

– RNC dimensioned based on assumed blocking.

– Peak traffic never seen by the RNC: Erlangs per BS can be converted into physical

channels per BS.

– NRT traffic can be divided with ( ).



• Dimensioning RNC based on the actual subscribers traffic in area.

Soft blocking

• Soft capacity only for real time services.

• Hard Blocking

– The capacity limited by the amount of hardware.

• Call admission based on number of channel elements.

– If all BS channel elements are busy, the next call comes to the cell is blocked.

– The cell capacity can be obtained from the Erlang B model.

• Soft blocking

– The capacity limited by the amount of interference in the air interference.• Call admission based on QoS control

• There is always more than enough BS channel elements.

– A new call is admitted by slightly degrading QoS of all existing calls.

– The capacity can be calculated from Erlang B formula. (too pessimistic).

• The total channel pool larger than the average number of channels.

– The assumptions of 2% of blocking. In average 2% of users experience bad quality

during the call. (Bad quality for voice 2%, bad quality for data 10%).



Soft capacity• Soft capacity is given by the interference sharing.

• The less interference coming from neighbouring cells the more channels are available in

the middle cells.

• The capacity can be borrowed from the adjacent cells.

– With a low number of channels per cell

• A low blocking probability for high bit rate real time users is achieved by dimensioning average load in

the cell to be low.

– Extra capacity available in the neighbouring cells.

• At any given moment it is unlikely that all the neighbouring cells are fully loaded at the same time.

• Soft capacity: the increase of Erlang capacity with soft blocking compared to that with

hard blocking with the same maximum number of channels per cell.

Algorithm for estimation:

• Calculate the number of channels per cell, N , in the equally loaded case, based on the

uplink load factor.

• Multiply total number of channels by to obtain the total pool in the soft blocking case.

C l l h i ff d ffi f h E l B f l

1 Erlang capacity with soft blocking

SoftCapacity Erlang capacity with hard blocking

= −



• Calculate the maximum offered traffic from the Erlang B formula.

• Divide the Erlang capacity by

Dimensioning for Voice and Data• Cell load factor

• Mixing different traffic types creates better statistical multiplexing:

– Dimensioning for the worst case load is normally not needed if resource pool is large enough.

– Delay intensive traffic can be used to fill the gaps in loading, using dynamic scheduling and

buffering.• Minimum cell throughput for NRT data should be planned for busy hour loading in

order to maintain some QoS.

• By filling the capacity not used by RT traffic we increase loading and in effect go after

the free capacity used for soft capacity, cell dimensioning becomes more complex.

Admission control

Admission control methods

d it if ibl

Prediction of the interference increase

• average bit rate of traffic source

• behaviour of traffic source

• environmental parameters

– expected average CIR

– spatial variability

E i i f UL/DL h

Load

max. planned load

Extra capacity

nominal capacity(demand)

Time of day



• admit if possible• threshold based systems

Estimates power increase for UL/DL when new

connection is admitted

Detailed planning

initialisation

phase

combined UL/DL

iteration

post processingphase

global

initialisation

END

post

processing

graphicaloutputs

coverage

analyses

downlink

iteration step

uplink

iteration step

initialise

iteration

Creating a plan,

Loading maps

Reporting

Neighbour cell

generation

Quality of Service

Analyses

WCDMA calculations

Model tuning

Importing

measurements

Link loss calculation

Importing/generating

and refining traffic

lauyers

Defining service

requirements

Importing/creating and

editing sites adn cells

Workflow of a RNP tool



END

Input data preparation• Digital map.

– for coverage prediction.

– totpoligical data (terrain), morphological data (terrain type), building location and height.

– Resolution: urban areas , rural areas .

• Plan.

– logical concept combining various items.

• digital map, map properties, target plan area, selected radio access technology, input parameters, antenna

models.

• Antenna editor.

– logical concept containing antenna radiation pattern, antenna gain, frequency band.

• Propagation model editor.

– Different planning areas with different characteristics.

– For each area type many propagation models can be prepared.

– tuning based on field measurements.

• BTS types and site/cell templates

– Defaults for the network element parameters and ability to change it.

– Example BTS parameter template:

• maximum number of wideband signal processors.



• maximum number of channel units.

• noise figure.

• Tx/Rx diversity types.

Planning• Importing sites.

– Utilisation of 2G networks.

• Editing sites and cells.

– Adding and modifying sites manually.

• Defining service requirements and traffic modelling.

– Bit rate and bearer service type assigned to each service.

– For NRT need for average call size retransmission rate.

– Traffic forecast.

• Propagation model tuning.– Matching the default propagation models to the measurements.

– Tuning functions per cell basis.

• Link loss calculation.

– The signal level at each location in the service area is evaluated, it depends on

• Network configuration (sites, cells, antennas). Propagation model. Calculation area. Link loss

parameters. Cable and indoor loss. Line-of-sigth settings. Clutter type correction. Topgraphic

corrections. Diffractions.

• Optimising dominance.

– Interference and capacity analysis.

i b i h l i i h i

Bearer service

definition

Traffic

modeling

mobile list

generation

WCDMA

calculation



– Locating best servers in each location in the service area.

– Target to have clear dominance areas.

Iterative traffic planning process

• Verification of the initial dimensioning.

• Because of the reuse 1, in the interference calculations also interference from

other cells should be taken into account.

• Analysis of one snapshot.– For quickly finding the interference map of the service area.

– Locate users randomly into network.

– Assume power control and evaluate the for all the users.

– Simple analysis with few iterations.

– Exhaustive study with all the parameters.

• Monte-Carlo simulation.

– Finding average over many snapshots: average, minimum, maximum, std.

– Averages over mobile locations.

– Iterations are described by:• Number of iterations.

• Maximum calculation time.

• Mobile list generation.

• General calculation settings.



Example of WCDMA analysis

• Reporting:– Raster plots from the selected area.

– Network element configuration and parameter setting.

– Various graphs and trends.

– Customised operator specific trends.

UL RXlevels

ULIteration

Active setsizes

OutageAfter DL

Traffic AfterDL

Best ServerDL

SHO areaBest Server

ULOutageafter UL

Traffic afterUL

Covergaepilot Ec/Io

Covrage

pilot Ec/Io

Throughput

DLEc/Io

Coverage

ULCell loading

Throughput

UL

Cell TXpowers

per link

DLIteration



Uplink iteration step

• Allocate MS transmit powers so that

the interference levels and BS

sensitivities converge.

• Transmit power of MS should fulfilrequired receiver Eb/Io in BS.

– Min Rx level in BS.

– Required Eb/Io in uplink.

– Interference situation.

– Antennae gain cable and other losses.

• The power calculation loop is

repeated until powers converge.

• Mobiles exceeding the limit power

– Attempt inter-frequency handover.– Are put into outage.

• Best server in UL and DL is selected.

Initialisation

calculate adjusted MS TX powers,check MSs for outage

Connect MSs to best server,calculate neede MS TxPower and

SHO gains

Evaluate UL break criterion

check UL loading and possibly moveMSs to new other carrier of outage

Calculate new coverage threshold

set oldThreshold to the default/newcoverage threshold

calculate new i=ioth/Iown

DL iteration step

post processing

END

convergence

check hard blocking and possiblytake links out if too few HW

resources

n o c

o n v e r g e n c e



Downlink iteration step

• Allocation of P-CPICH powers.

• Transmit power of BS should fulfil

required receiver Eb/Io in MS.

• The initial Tx powers are assigned

iteratively.

• The target CIR

• The actual CIR

• The planning tool evaluates the actual

( )1 ,1

N nk nk

nk k n nk oth n k

P LPC

I P LP I N α =

= − ⋅ + + ∑

0arg

bt et E N CIR

W R=

Global Initialisation

calculate target C/I’s

calculate initial TX powers for alllinks

determine the SHO connections

calculate the received Perch levelsand determine the best server in DL

allocate the CPICH powers

Initialise deltaCIold

post processing

END

calculate the MS senisitivities

Adjust TX powers of each remaininglink accordingly to deltaCI

check UL and DL break criteria

calculate the SHO diversitycombining gains; adjust the required

change to C/I

check CPICH ec/Io

calciulate the C/I for each connectioncalculate C/I for each MS

update deltaCIold

fulfilled

UL iteration stepInitialise iterations



iteratively. The planning tool evaluates the actualCIR and compares it to the Target CIR

Coverage analysis

UL DCH Coverage

• Whether an additional mobile having certain bit rate could be served.

• The transmit power need for the MS is calculated and compared to the maximum

allowed:

( )

0,

1 1

TX MS N LPP

W

Rν η

ρν

=− +

( )

tx N

n

k AS k tot k ms

R W P

LP I I N

ρ

β α ∈

≥

− +∑

DL DCH Coverage

• Pixel by pixel is checked whether an additional mobile having certain bit rate could beserved. Concentration on the power limits per radio link.

• The transmit power need for supporting the link is calculated and compared to the

maximum allowed:

DL CPICH Coverage

• Pixel by pixel is checked whether the P-CPICH channel can be listened.

CPICH P LPCPICH =



, _ _ 0

1

numBSs

TX i i adjacent channel CI

i

P LPCPICH

P LP I N =

=+ +∑

Dynamic simulation• Complexity prohibit the usage in actual network planning.

• Is used to verify the planning made by other tools.

• Can consider:

– power control.

– soft handover.

– packet scheduling.

• Good for benchmarking Radio Resource Management.

• Statistic can coverage:

– Bad quality calls: Calls with average frame error rate exceeding the threshold.– Dropped calls: Consecutive frame errors exceed the threshold.

– Power outage: Power requirement exceeds the available Tx power.

Conclusions• Cell level results are in good agreement with both, dynamic and static results.

• The outage areas are in the same locations if investigated with different

simulations.



Radio Resource Management



Content of the lecture

Changing capacity.• Admission control.

• Packet scheduling.

• Load Control.

• Resource management.

• Power control.

• Handover control.



Changing Capacity

RRM purpose.

• Ensure planned coverage for each

service.

• Ensure required connection quality.• Ensure planned (low) blocking.

• Optimise the system usage in run time.

Real time RRM and

Optimisation functions.• Interference measurements.

• Soft capacity utilisation.

• Scheduling in radio interface.

• Actions to load change.

• Real time interference minimisation:

– Handover control.

– Service prioritisation.

– Connection parameter settings.Admission control

Link Quality

Optimisationand tailoring

Cell coverage Cell Capacity

Uplink interference power

Prx_threshold

Prx_target

Overload area

Marginal load area

Max planned load

Planned load area

Prx

Load



– Admission control.

WCDMA radio network controlIn WCDMA QoS will be controlled by:• Radio Network Planning. (Network Parameters.)

• Real time RRM (Radio Resource Management) operations in RNC BS.

• Real time power control.

• RRM is operating on connection and cell

bases.

Power ControlPower ControlLoad Control

Admission ControlPacket Scheduler

Load ControlResource Manager

Power ControlHandover Control

MS BS

DRNC

SRNC

Admission ControlLoad Control

Resource Manager

Power ControlLoad Control

Radio Resource Management.

RRM functionality is aset of algorithms used

for optimal utilisation of

air interface and HW

resources.



• System load is measured in run time.

RRM methodsNetwork based functions.• Admission control (AC).

– Handles all new incoming traffic. Check whether new connection can be admitted to the system

and generates parameters for it.

– Occurs when new connection is set up as well during handovers and bearer modification.

• Load control (LC).

– Manages situation when system load exceeds the threshold and some counter measures have to be

taken to get system back to a feasible load.

• Packet scheduler (PS).

– Handles all non real time traffic, (packet data users). It decides when a packet transmission isinitiated and the bit rate to be used.

• Resource Manager (RM).

– Controller over logical resources in BTS and RNC and reserves resources in terrestrial network.

Connection based functions.

• Handover Control (HC).

– Handles and makes the handover decisions.

– Controls the active set of BS of MS.

• Power Control (PC).

– Maintains radio link quality.



– Minimise and control the power used in radio interface.

Interworking actions of AC, PS, and LC

perventive

state

overloadstate

no new

RAB

Drop RT bearers

overload

actions

decrease bit rates

NRT bearers

to FACH

drop NRT bearers

only bew RT

bearers if RT load

below PrxTarget/

Prxtarget

AC admitsRABs normally

no actionPS schedulespacket traffic

normally

no new capacity

request scheduled

bit rate not

increased

preventive loadcontrol actions

PrxTarget or

PtxTarget

PrxTarget+PrxOffset orPtxTarget+PtxOffset

normal

state

AC PSLC

In uplink.

the optimal average

the maximum margin by which can be exceeded.

In downlink. , the optimal average for .



, the optimal average for .

, the maximum margin by which can be exceeded.

Air Interface Load: Uplink

Wideband power based uplink loading.• The BS measures the total received power .

• The Uplink loading can be described by

– Load factor

– Noise rise

Throughput based uplink loading

• The UL loading is calculated based on the individual load factor of each individualuser.

rxTotal own oth nP I I P= + +

Noise Rise=PrxTotal/PrxNoise

Prx_threshold

Prx_target

Overload area

Marginal load area

Max planned load

Planned load area

NR=?

Load

Prx_Noise

NoiseRiseTarget=

Prx_target/PrxNoise

oth

rxTotal

I P

η +

1_

1

rxTotalUL

N UL

P Noise Rise

P η = =

−

( )

1

1 1UL

k

k k k

W i

R

η

ρ ν

=+ ⋅ +

⋅ ⋅

∑



Air Interface Load: Downlink

Wideband power-based downlink loading.

• The load can be estimated by dividing the total currently allocated transmit

power at the BS by the maximum transmitted power capability of the cell:

Throughput based downlink loading.

• The loading is the sum of the bit rates of all currently active connectionsdivided by the maximum throughput of the cell:

• Alternatively. Loading is calculated by using concepts of orthogonality other-

to-own cell interference:

txTotal DL

tx

P

Pη =

1

N

k

k DL

R

η ==∑

( )1

1

N

DL DL

k k k k

W iR

η α ρ ν

= − + ⋅ ⋅∑



1k k k k R ρ ν = ∑

Admission control

• Decides whether new RAB is admitted or not.– Real-Time traffic admission to the network is decided.

– Non-Real-Time traffic after RAB has been admitted the optimum scheduling is determined.

Co-operation with PC.

•Used when the bearer is

– Set up.

– Modified

– During the handover.

• Only downlink is considered in UL the BS is already measuring a MS as and other to own cell

interferecnce.– In new branch the AC is needed for initial power allocation.

• In inter-frequency handovers the UL is also considered.

• Estimates the load and fills the system up to the limit.

• Used to guarantee the stability of the network and to achieve high network capacity.

• Separate admission for UL and DL.– Load change estimation is done in the own and neighbouring cells.

– RAB admitted if the resources in both links can be guaranteed.

– In decision procedure AC will use thresholds set during radio network planning.

• The functionality located in the RRM of the RNC.



Power based admission control

Uplink • The bearer is admitted if RT load fulfils: and total

received wideband power fulfils .

• For NRT only the latter condition is applied.

• The increase of wideband power is estimated as

–

– .

• The fractional load for the new user can be calculated .

I + ∆ ≤

≤ +

1 I L

η ∆ ≈ ⋅ ∆

−

1 I L Lη ∆ ≈ ⋅ ∆− − ∆

1

1

LW

R ρ ν

∆ =+

⋅ ⋅

Downlink

• RT bearer will be admitted if non-controllable downlink load fulfils equation

and total transmitted power fulfils .txNC P P+ ∆ ≤ txTotal txOffset P P≤ +



Throughput based admission control

• A new bearer is admitted only if the load after admittance stays below the

threshold defined by RNP.

Uplink

Downlink

oldUL thresholdUL Lη η + ∆ ≤

oldDL thresholdDL Lη η + ∆ ≤



Admission control

• In the decision procedure AC will use threshold form network planning and from

interference measurements.

• The new connection should not impact the planned coverage and quality of existingconnections. (During the whole connection time.)

• AC estimates the UL and DL load increase which new connection would produce.

AC uses load information from LC and PC.

• Load change depends on attributes of RAB: traffic and quality parameters.

• If UL or DL limit threshold is exceeded the RAB is not admitted.

• AC derives the transmitted bit rate, processing gain, Radio link initial quality

parameters, target BER, BLER, Eb/No, SIR target.

• AC manages the bearer mapping

– The L1 parameters to be used during the call.

• AC initiates the forced call release, forced inter-frequency or intersystem handover.



Logical dependencies of AC

Load change estimation

RAB admissionL2 parameters

Transport Format CombinationDL Power allocation

ACRadio Resource Info- Codes

- Transport resources

PSRM

PC HC

LC

Target BER/BLER/SIR

Active set info

Resource info

Resource request

RB info

Load Info

Load ChangeInfo

Load Info

IubBearer set up request



Packet scheduling• To determine the available radio interface resources for non real time radio bearer.

• To share the available radio interface resources between non real time radio bearers.

• to monitor the allocations for non real time radio bearers.

• To initiate transport channel type switching between common, shared and dedicated

channels when necessary.

• To monitor the system loading.

• To perform load control actions for the non-real-time radio bearers when necessary.

Packet call

RACH/FACH, CPCH,DSCH, DCH allocation

NRT RAB allocated, packet service session

AC handles

b i t r a t e

time

PS handles

L o a d

max. planned load

Possible NRT load

non controllable load

time



Properties of WCDMA transport channels

applicable for packet data transferTrCh DCH RACH FACH CPCH DSCHTrCH type Dedicated Common Common Common Shared

Applicable UEstate

CELL_DCH CELL_FACH CELL_FACH CELL_FACH CELL_FACH

Direction Both Uplink Downlink Uplink Downlink

Code Usage Accordingly to

maximum bit

rate

Fixed code

allocations in a

cell

Fixed code

allocations in a

cell

Fixed code

allocations in a

cell

Fixed code

allocations in a

cellPower control Fast closed-

loop

Open-loop Open-loop Fast closed-

loop

Fast closed-

loop

SHO support Yes No No No No

Target data

traffic volume

Medium or

high

Small Small Small or

medium

Medium or

highSuitability for

bursty data

Poor Good Good Good Good

Setup time High Low Low Low Low

Relative radio

performance

High Low Low Medium Medium or

high



Configurations for transport channel

• AC determines the Transport Channel parameters (RNC,

BS, MS).• Transport format (RNC, BS, MS).

• AC/PS determine a Transport Format Combination in

DCN multiplexing (RNC, BS, MS).• Service multiplexing and rate matching are controlled

(RNC)

• AC/PS determine a Gain factor for the uplink

DPCCH/DPDCH power difference. (MS RNC)



Load Control

Purpose: optimise the capacity of a cell and prevent overload– The interference main resource criteria.

– LC measures continuously UL and DL interference.

– RRM acts based on the measurements and parameters from planning

Preventive load control.

– In normal conditions LC takes care that the network is not overloaded and remains

stable.

Overload condition.– LC is responsible for reducing the load and bringing the network back into operating area.

• Fast LC actions in BTS:

– deny (DL) or overwrite (uplink) TPC ‘up’ commands.

– Lower SIR target for the uplink inner-loop PC.

• LC actions located in the RNC.

– Interact with PS and throttle back packet data traffic.

– Lower bit rates of RT users.(speech service or CS data).

– WCDMA interfrequency or GSM intersystem handover.

– Drop single calls in a controlled manner.



Traffic types and load

• Non controllable traffic

– Real-time (RT) users (traffic).

– Users in other cells.

– Noise.

– NRT users with minimum bit rate.

• Controllable traffic.

– Non-real-time users (traffic).

P o w e r

Load Target

Estimated Capacityfor NRT load

non controllable load

time

Overload margin

Overlaod Area

Some slice of capacity must be

allocated to the non controllabletraffic for mobility purposes all the

time. The proportion between

controllable and non-controllable

traffic varies all the time.

• Uplink received power.

• Downlink received power.

= + + = +

txTotal txNc txNRT P P P= +



Description of LC

• LC consists of AC, PS algorithms and LC, updating load status based on the

measurements and estimations from AC and PS.

LC algorithm• BTS measures the total received power.

• BTS reports measurements to the Controlling-RNC. (periodically).

• RRM in RNC updates cell load status for each controlled cell.

• AC and PS work based on the current load status in the cell.

• The load is estimated based on received noise power. PrxNoise.

– Overestimation -> under estimation of cell load, can lead to overload situation.

– Underestiamtion -> overestimation of the cell load, causes low system utilisation(unnecessary call blocking).



Resource management

• Purpose: to allocate physical radio resources when requested by the RRC

layer.

• Knows radio network configuration and state data.

• Sees only logical radio resources.

– Allocation is a reservation of proportion of the available radio resources according

to the channel request from RRC layer for each radio connection.

• Input comes from AC/PS.

• RM informs PS about network conditions.

• Allocates scrambling codes in UL.

• Allocates the spreading codes in downlink direction.

– Able to switch codes and code types

• During soft handover.

• defragmentation of code tree.



Power control

• Uplink open loop power control.• Downlink open loop power control.

• Power in downlink common channels.

• Uplink inner (closed) loop power control.• Downlink inner (closed) loop power control.

• Outer loop power control.

• Power control in compressed mode.



Uplink open loop PC

• Setting the initial transmission power.

• The terminal sets the initial power for the first PRACH preamble and for the DPCCH

before starting inner loop PC.

_ _CPICH Tx Power =− ++

_ _ DPCCH Power Offset = −

( )10

_ _

10 log DPCCH DPDCH

CPICH Tx Power

SIR SF

= +

+ − ⋅

is measured at the BS and broadcast on the BCH.

• First DPCCH power level for the uplink inner-loop PC is started as.

is measured bye the terminal.

is calculated by AC in the RNC and provided to MS during a

radio bearer or physical channel reconfiguration.

is the initial target SIR produced by the AC for the particular connection.

is the spreading factor of the corresponding DPDCH.

DPCCH SIR

DPDCH SF



Downlink Open loop PC

• The open loop PC is used to the the initial power of the downlink

channelsbased on downlink measurement reports.

• The function is in UTRAN and MS.

• A possible algorithm for initial power calculations is

( )

( )0

0

_ _b Initial DLTx

b CPICH

R E N CPICH Tx power P PtxTotal

W E N α

⋅= − ⋅

user bit ratedwonlink planned Eb/No set by RNP for particular bearer service.

the chip rate.

reported by MS.

the downlink orthogonality factor.carrier power measured at the BS an reported to the RNC.

R( )0b DL E N

W

( )0b CPICH E N

α

PtxTotal



PC in downlink common channels• Determined by the network.

• The ratio of the transmit powers between different downlink common channels not

specified in recommendations.

DL commonchannels

Typical powerlevel

Note

P-CPICH 30-33 dBm 5-10% of maximum cell Tx power (20 W). Set during

Network planning.P-SCH S-SCH -3 dB Relative to P-CPICH power.

P-CCPCH -5 dB Relative to P-CPICH power.PICH -8 dB Relative to P-CPICH power and Number of paging

indicators per frame Np = 72.AICH -8 dB Power of one Aquisation Indicator (AI) compared to P-

CPICH power.

S-CCPCH -5 dB Relative to P-CPICH and SF=256 (15 ksps). Theconfiguration covers FACH power, max FACH power,

PCH power.

FACH slow PC can be applied.

PDSCH Inner loop PC TPC commands from user. A proprietary protocol for

slow PC can be used.



UL/DL inner and Outer loop PC

• Inner loop PC relies on the feedback information at Layer 1.

• The fast PC is used in UMTS for the dedicated channels in

uplink and downlink.

• PC commands update rate1500 Hz

MS

BS

RNC

P C o n

D P C C H + D

P D C H

U L / D L

T P C c

o m m a

n d s o n

D P C C

H R R C : a c

t u a l B L

E R, P -

C P I C H E c / I o,

P - C P I C

H R S C P, p a

t h l o s s, t r a

f f i c + M S

i n t e r n a l m e

a n s

D C H - F P ( 1 0

- 1 0 0 H z ) :

U L C R C

D L a c t u a l t a r

g e t S I R

N B A P : I n

i t a l t a r g

e t S I R, D L

i n i t a l / m

a x /

m i n R L p o w e r,

D L T P C

, D P C_ M O D E

R R C : D L t a r g e t

B L E R, U L g a

i n f a c t o r s

, U L T P C

, P C a l g

o r i t h m

, U L R M v a l

u e s,

D P S_ M O D E

P C o n

D P C C

H o n l y

UL outer loop PC

SIR = f(BLER (BER)SIR target measurements

SIR estiamte vs. target SIRUL TPC commands

DL outer loop PCSIR = f(BLER (BER)

SIR target measurementsSIR estiamte vs target SIR

DL TPC commands



Uplink closed loop PC

• Received signal power is compared to the CIRtarget and depending on the resulttransmission power is asked to increase to decrease.

– CIRtarget is got from uplink outer loop PC.

• Performance depends on users speed

– v < 30 km/h step size 1 dB. (Algorithm 1).

– 30< v <80 km/h step size 2 dB. (Algorithm 1).

– 80 < v PC can not follow the channel changes and generates only noise (Algorithm 2).

• Before starting the communication a DPCCH PC preamble could be send.

– For convergence of the uplink Tr power. 0-7 frames (the number set during RNP).

Fast PC algorithm: 1• The PC command is received and that can be +1 or -1 dB

PC during handover

– Commands know to be same are combined into one command that is combined further with other

TPC commands

– commands not known to be the same

• soft symbol decision on each of the PC commands TPCi where i=1…N

• to each symbol is assigned a realiability figure Wi

• The TPC commands are combined as function of of all N power control commands TPCi

and reliability estimates Wi:

TPC_cmd= (W1,W2,..,WN,TPC1,TPC2,…,TPCN), where TPC_cmd ∈ -1,1



Fast PC algorithm: 2• Allows:

– To emulate smaller step sizes for PC.

– To turn off uplink PC.

• PC commands processed in non overlap 5 slot cycle.

• TPC_cmd

– for the first 4 slots of a set TPC_cmd = 0

– for the fifth slot is used hard decision

• all hard decisions 1 TPC_cmd = 1.

• all hard decisions 0 TPC_cmd = 0.

• Otherwise TPC_cmd = 0.

Algorithm 2 during handover.

• Combining TPC_cmd known to be same. The commands are combined into one command

• Combining TPC_cmd not known to be same

– MS makes PC decision over 3 slots

– sums all the decisions that are not known to be same in a slot

– the TPC_cmd for two first slots is 0 and for the third slot it is either - 1, 0, + 1 depending on the

value of the normalised sum of PC bits

• Example: TPC_cmd set accordingly

– +1 if 1/N

∑i TPC_cmdi > 0.5

– -1 if 1/N∑i TPC_cmdi < 0.5

– otherwise 0



DL fast closed loop PC• MS estimates the received SIR and compares it with required SIR target.

– SIR is estimated from the pilot symbols of the DL-DPCH

• MS transmits the TPC command in first available TPC field.

• Two downlink PC modes:

– DPC_MODE = 0: power command in every slot.– DPC_MODE = 0: power command once in every third slot.

• Power difference for different channels is estimated from given power offset

values.

• Changes of power are multiplies of the minimum step size

– it is mandatory for BS to support 0.5 and 1 dB step size

Data DataTPC TPCI Pilot

PO2 PO1 PO3

Tslot=2560 chips

DPDCH DPCCH DPDCH DPCCH

TL Txpower

DL DPCH



DL power during handover

Softer handover (diversity transmission).

– Only one TPC is send.

– Signals from different antennas are combined in the symbol level.

Soft handover.– The signals are combined in MS.

– Power drifting?

• In Soft handover mode only one single TPC is send in uplink.

• Each cell detects TPC command independently.– Possible errors. Some BS may lower the Tx power when others increase -> the Tx powers

are drifting apart.

• The transmission code power levels of athe connecions from the cell in SHO are

forwarded, after averaging, to RNC.

– Averaging for example 750 TPC commands (500 ms).

• RNC derives a reference power values and send to the cells.



Outer loop PC• Outer loop power control produces an adequate target CIR for inner loop PC.

• Done for each DCH belonging to the same RRC connection.

• Frequency typically 10-100 Hz.

• During Soft HO.

– The UL quality is observed after the MDC. The SIR target is generated for all cells in SHO.

• The reliability of the blocks is provided to RNC. The quality is estimated based on CRC codes.

• DL the outer loop PC

implemented in MS.– In CPCH a quality target is

DPCCH BER.

– DPCCH BLER quality taret

otherwise.

• The value of the DL otuer loop PCis controlled by the AC in RNC.

– The value of the target is send to

MS in a RRC message.

Node B

LC

AC

UL Outer LoopPC Controller

New SIR targetcomputation

New SIRtarget

SIR Target

modificationcommand Quality info

BLER/BER

New SIRTarget

PC parametersat RAB setup/radio link

reconfiguration

Inital SIR target

UL Outer loop PCEntry #

Calculation of SIRtarget change

Transmission ofthe new SIR target

value ot BTS

MDC

MDC

MDC

RNC



PC in compressed mode

• Aim to recover a SIR close to the target SIR after each transmission gap

• In downlink compressed mode no PC is applied during transmission gap

• In simultaneous DL/UL compressed mode transmission is stopped

• The initial tr power of each UL after the tr gap is equal to the power before the gap,

but with an offset resume

• resume may be

– 0

– resume = Int[σlast / TPCmin] TPCmin

σlast =09375 σlast-1 -096875 TPCcmdlast TPC• PC modes are fixed and signalled with the other parameters during the downlink

compressed mode

– ordinary PC is applied

– ordinary PC is applied with step size RP-TPC during RPL slots after transmission gap.

• RP-TPC is recovery PC step size in dB

– if algorithm 1 used is is equal to the minimum value of 3 dB and 2 TPC

– if algorithm 2 is used RP-TPC is equal to 1 dB

• RPL is recovery period length and is expressed in number of slots



Handovers

• Intrasystem HO.

– Intrafrequency HO.

– Interfrequency HO.

• Intersystem HO.

• Hard HO (HHO).

– All the old radio links of an MS are released before the new radio links are established.

• Real time bearers: short disconnection in transmission.

• Non real time bearers HHO is lossless.

• Soft HO (SHO).

– MS always keeps at least one radio link to UTRAN.

– Soft HO: MS is simultaneously controlled by two or more cells belonging to diffetrent BTS of

the same RNC or to different RNC.

– Softer HO. MS is controlled by at least two cells under one BTS.

• Mobile evaluated handover (MEHO).

– The UE mainly prepares the handover decision. The final decision is made by SRNC.

• Network evaluated handover (NEHO).

– The SRNC makes the handover decision.



Intrasystem intra-frequency HOObjectives of soft / softer HO.

• Optimum fast closed loop PC as the terminal is always linked with the strongest cells.

• Seamless handover with no disconnection of the radio access bearer.

• Diversity gain by combining the received signals from different cells. Better coverage. Less

transmission power.

• MEHO: MS continuously measures serving and neighbouring cells on the current carrier.

• The RAN can perform soft and softer HO simultaneously.

General HO activities.

• Reporting of the MS measurements.

– Compares measurement results with the HO threshold.

– MS sends reports to BTS when the criteria is met.

• Threshold is provided by the RNC.

• Comparison result is transmitted to RNC.

• HO decision.

– SRNC orders MS to add or remove cells from/to Active set.

• Measurement reporting criteria.

– Definition of event that triggers the measurement report.

– Parameters are defined on cell bases.



RRM functions in HO processRRM functions

HC: processes the measurements made by terminal and makes decisions. Updates

reference transmission powers.

AC: DL admission decision: acceptance and queuing. DL power allocation. May initiate a

forced call release of IF-HO IS-HO.RM: Activates/deactivates HO brances. Allocates/releases DL spreading codes.

LC: Updates DL load information when new HO link is admitted.

PS: Releases codes for HO brances of NRT. Schedules HO additions requests for NRT

• DL channelisation codes are allocated separately for each soft(er) HO branch.

• UL channelisation code is the same for each soft(er) HO branch.



Measurements reporting

• The measurements based on Eb/Io.

• The MS constantly monitors the CPICH Eb/Io of the cells defined by the

neighbouring list.

• If the reporting criteria is fulfilled MS sends a event triggered measurement

report

• The CPICH Eb/Io is the received energy per chip divided by the power density

in the band.

• The accuracy of pilot Eb/Io important for HO performance.

– The accuracy depends on the filtering length and mobile speed.

HO measurements reporting can be divided as:

• Neighbouring cell definitions.

• Measurement reporting criteria.

• Reporting of measurement results.



Neighbouring cellsFor each cell in the radio network configuration database are defined a list of neighbouring

cells.

• Intrafrequency neighbouring list. The UE must be able to monitor at least 32 cells on

the same WCDMA carrier frequency as the serving cell.

• Interfrequency neighbouring list. The UE must be able to monitor at least 32 cells on

the two other WCDMA carrier frequencies compared to the serving cell.

• Intersystem neighbouring list. For each neighbouring PLMN a separate list is

maintained.

Measurement reporting criteriaDepending on the hondover type (MEHO, NEHO) different measurement reporting criteria can

be used.

• Intrafrequency measurements.(MEHO).

– HO measurements. The RAN broadcast the measurements reporting criteria (measuremetns

parameters on the BCCH.

• Interfrequency and Intersystem measurements.

– Made only when requested by RNC.

– When once initiated MS periodically reports the measurement results to RNC

• UE internal measurements.– Controlled cell by cell bases. Info transmitted to MS in DCCH.



Reporting Intrafrequency measurmentsCan be either event-triggered or periodic.

Reporting criteria for intrafrequency measurements are:

• Event 1a: A p-CPICH enters the reporting range.

• Event 1b: A P-CPICH leaves the reporting range.

• Event 1c: A non-active P-CPICH becomes better than an active one.

• Event 1d: Change of best cell. Reporting event is triggered when any P-CPICH in the

reporting range becomes better than thet current best one plus an optional hysteresis

value.

• Event 1e: A P-CPICH becomes

better than an absolute threshold

plus an optional hysteresis value.

• Event 1f: A P-CPICH becomes

worse than an absolute minus anoptional hysteresis value.

P-CPICH 4

P-CPICH 1

P-CPICH 2

P-CPICH 3

P-CPICHEc/Io

Additionwindow

Replacementwindow

Dropwindow

Event 1a Event 1e Event 1C Event 1bEvent 1d Event 1cReporting of:



Intrafrequency measurements (2)

• Event 1a.

• Event 1b.

( ) ( ) ( )10 10 1 1

110 log 10 log 1 2

A N

new i Best a a

i M W M W M R H

=

⋅ ≥ ⋅ ⋅ + − ⋅ − − ∑

( ) ( ) ( )10 10 1 1

1

10 log 10 log 1 2 A N

Old i Best b b

i

M W M W M R H =

⋅ ≤ ⋅ ⋅ + − ⋅ − + ∑

Time to trigger mechanism.

• To protect the network from excessive signalling in case of frequent reports.

– The reporting events could have a timer.

• If the measuring criteria is fulfilled during the whole period the event is reported.

Periodic Reporting.

• If the operation (AS update) can not occur because lack of HW the MS continues to send

periodic reports.

the measurement result of the cell enteringthe reporting range.

a measurement result of a cell in the active

set.

the number of cells in the current active set.

the measurement result of the strongest cell

in the active set.a weighting parameter sent from RNC to UE.

new M

i M

A N

Best M

W

1a R

1a H

1b R

1b H

Old M

the reporting range for Event 1a sentfrom RNC to UE.

the hysteresis parameter for Event 1a.

the reporting range constant for Event

1b sent from RNC.

the measurement result of the cell

leaving the reporting range.the hysteresis parameter for Event 1B.



Date post:	03-Jun-2018
Category:	Documents
Upload:	salaheddinmahasneh
View:	216 times
Download:	0 times

W CDMA Lectures

Documents