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© Alcatel University - 8AS 90171 0004 VT ZZA Ed. E.A.U

UMTS/UTRANIntroduction




Introduction to UMTS

Table of contents

1.1. IntroductionIntroduction

2.2. Services ProvidedServices Provided

3.3. UMTS system descriptionUMTS system description

4.4. WCDMA for UMTSWCDMA for UMTS

5.5. UTRAN (Release 1999)UTRAN (Release 1999)

AppendixAppendix

Related DocumentationRelated Documentation

Abbreviations and acronymsAbbreviations and acronyms




1.1.

IntroductionIntroduction




1.Introduction

Definition

Universal

Mobile

Telecommunication

System

“UMTS is one of the major new third generation mobile

communications systems being developed within theframework which has been defined by the ITU and known as IMT-2000”

UMTS Forum




1. Introduction

1.11.1 ContextContext

1.21.2 StandardizationStandardization

1.31.3 UMTS goalsUMTS goals

1.41.4 UMTS technical overviewUMTS technical overview




1.Introduction/1.1 Context Past mobile systems (1)

First Generation (1G)

In the early 80’s, analog systems

e.g Radiocom 2000, C-Netz…

Service:speech

Limitations of 1G:•poor spectrum efficiency•expensive and heavy user equipment•mobility only in a small area•no security of communications




1.Introduction/1.1 Context Past mobile systems (2)

Second Generation (2G)In the early 90’s, digital systemsEurope : GSMUS : IS-95 (also called cdmaOne), IS-136 (TDMA system)

Japan : PDC

Services: Speech and low data rateLimitations of 2G:• Congestionmore than 300 million wireless subscribers worldwide -->need toincrease system capacity

• Limited mobility around the world -->need for a global standardisation

• Limited offer of servicesmore than 200 million internet users--> Need for new multimediaservices and applications (video telephony, e-commerce...)




1.Introduction/1.1 Context

Technical solutions

Two types of solutions were possible :

• enhancement of 2G system --> 2,5Glow cost but short term

e.g.: HSCSD, GPRS, EDGE for GSM evolution

• design of a complete new standard --> 3Ghigh cost, long term, but great amount of new potential servicese.g: UMTS




1.Introduction/1.1 Context GSM evolution (1)

HSCSD (High Speed Circuit Switched Data)Principle: to enhance channel coding scheme and to bundle GSMtime slots on a circuit-switched basis.

Performance: up to 115,2 kbps

Already implemented but not all operators/manufacturers havemade this choice.

GPRS (General Packet Radio Service)

Principle: to enhance channel coding scheme and to bundle GSMtime slots on a packet-switched basis (the allocation of time slots

is performed dynamically at the initialisation and during theconnection)

Performance: up to 171,2 kbps

1999/2000 : deployment phase2002 : service offers for most operators




1.Introduction/1.1 Context GSM evolution (2)

EDGE (Enhancement Data rates for GSM evolution)

Principle: new modulation scheme (8PSK instead of GMSK)

Performance: up to 384 kbps

Implementation is yet to come (foreseen for 2003)

EDGE might be a good alternative to 3G systems in certain areasor for operators who do not have 3G licences, although the 3Gbrings more in terms of new multimedia services.




1.Introduction/1.1 Context

Let’s take some examples!

w A 2 1/2 minutes MP3 musicfile (2.4 MBytes)

GSM 34mnGPRS 7mnEDGE 128sUMTS 10

s

w Audio and Video

streaming

Streaming with alltechnologies

except with GSM

w Downloading a map (50

KBytes)

GSM 42sGPRS 8sEDGE 3sUMTS 0.2

s

w Downloading a Word document

(500 KBytes)

GSM 7 mnGPRS 82 sEDGE 27 sUMTS 2 s




1.Introduction



1.31.3 UMTS GoalsUMTS Goals





1.Introduction/1.2 Standardization

IMT-2000: definition

IMT-2000 is a framework for third generation mobile systems (3G)which is scheduled to start service worldwide around the year2000 subject to market considerations.

IMT-2000 should use the frequencies around 2 GHz all over theworld.

IMT-2000 is defined by a set of interdependent ITURecommendations*.

IMT-2000 main requirements are :- wide range of high quality services- capability for multimedia applications- worldwide roaming capability- compatibility of services within IMT-2000 and with the fixednetworks




1.Introduction/1.2 Standardization IMT-2000: main

participants

Europe: ETSI

Japan: ARIB

USA: TIA, T1

South Korea: TTA

China: CWTS

ITU: International TelecommunicationUnion




1.Introduction/1.2 Standardization IMT-2000: terrestrial

radio interfaces

IMT-TC (Time Code) TD-CDMAUMTS TDD

IMT-DS (Direct Spread)W-CDMAUMTS FDD

IMT-MC (Multi Carrier)CDMA2000FDD MC

IMT-SC (Single Carrier) TDMA Single CarrierUWC-136EDGE/ERAN

IMT-FT (Frequency Time) TDMA Multi-CarrierDECT

Radio/NetworkConnection

Evolved IS-41Core Network

Evolved GSMCore Network




1.Introduction/1.2 Standardization 2G terrestrial radio

interfaces

1999 MarketShare:

GSM 48 %CDMA 28 % TDMA 15 %PDC 9 %

Western Europe:

Japan:

Rest of the World :

US & Canada :

GSM(100%)

GSM(87%)

CDMA(13%)

PDC(64%) CDMA

(36%)

GSM(12%)

CDMA(49%)TDMA

(39%)

GSM(41%) CDMA

(35%) TDMA(24%)

China :




1999 MarketShare:

GSM 48 %CDMA 28 % TDMA 15 %PDC 9 %

UMTSCDM

A2000

EDGE

IMT2000

1.Introduction/1.2 Standardization 3G terrestrial radio

interfaces

Western Europe:

Japan:

Rest of the World :

US & Canada :

GSM(100%)

GSM(87%)

CDMA(13%)

PDC(64%) CDMA

(36%)

GSM(12%)

CDMA(49%)

TDMA(39%)

GSM(41%) CDMA(35%) TDMA

(24%)

CDMA

2000

UMTS

UMTS

UMTS

UMTS

EDGE

EDGE

CDMA

2000

CDMA

2000UMTS

UMTS

CDMA

2000EDG

E

China :




1.Introduction/1.2 Standardization 3GPP: joint organizationfor UMTS standardization

Affiliated organizations:ETSI (Europe) ARIB/TTC (Japan)

T1 (USA) TTA (South Korea)CWTS (China)

Other members involved: manufacturers and operators

System Specification:

Access NetworkWCDMA (UTRA FDD)

TD-CDMA (UTRA TDD)Core Network

Evolved GSMAll-IP

Releases defined for the system specifications:- Release 99 (called R3 as well)- Release R4 and R5 (previously known as Release 2000 or R’00)

In the following material we will only refer to UMTS R99.




1.Introduction/1.2 Standardization 3GPP: TSG organization

CN WG1

Mobility Management,Call Control,

Session Management

CN WG2

CAMEL

CN WG3

Interworking with

External Networks

TSG CN

Core Network

RAN WG1Radio layer 1

specification

RAN WG2

Radio Layer 2 &

Radio Layer 3 RR

specification

RAN WG3

Iub, Iur, Iu specification &

UTRAN O&M requirements

RAN WG4

Radio performance &

Protocol aspects

TSG RANRadio Access Networks

SA WG1Services

SA WG2

Architecture

SA WG3

Security

SA WG4

CODEC

SA WG5

Telecom Management

TSG SA

Service and System

Aspects

T WG1

Mobile TerminalConformance Testing

T WG2

Mobile terminalservices & capabilities

T WG3

Smart Card

Application aspects

TSG T

Terminals

CN WG4

MAP/GTP /BCH/SS

CN WG5

OSA

Open Service Access

TSG GERAN

GSM EDGE

Radio Access Network

GERAN WG1Radio Aspects

GERAN WG2

Protocol Aspects

GERAN WG3

Terminal Testing

Project Co-ordination Group

(PCG)




1.Introduction/1.2 Standardization 3GPP specifications

Series_Id Series_description21. Requirements22. Service Aspects23. Technical Realization24. Signaling Protocols (UE to network)25. UTRA aspects

26. CODECs27. Data28. (reserved)29. Signaling Protocols (intra-fixed network)30. Program management31. User Identity Module32. O&M33. Security Aspects34. Test specification35. Security algorithms

h t t p:// w w w

. 3 g p p. o r g/ s

pe c s/ s pe c s

. h t m




1.Introduction/1.2 Standardization UMTS Roadmap

EDGEEDGECommercialCommercialintroductionintroduction

UMTS R5UMTS R5

UMTS R99UMTS R99Field TrialsField Trials

2001 20032002

GPRSGPRSimplementationimplementation

UMTS R99UMTS R99commercialcommercial

SystemSystem

2004

1 I t d ti




1.Introduction


1.21.2

StandardizationStandardization






1.Introduction/1.3 UMTS goals Why UMTS?

“UMTS will be a mobile communication system that offerssignificant user benefits including high-quality wirelessmultimedia services to a convergent network of fixed, cellular and satellite components.”

It will deliver information directly to users and provide them withaccess to new and innovative services and applications.

It will offer mobile personalized communications to the massmarket regardless of location, network and terminal used.”

UMTS Forum 1997




1.Introduction/1.3 UMTS goals UMTS vision

Satellite

Macro-CellMicro-Cell

Zone 2: Urban

Zone 1: In-Building

Pico-Cell

Zone 4: Global

Zone 3: Suburban

UTRA/TDDUTRA/FDDMSS

GSM

1 Introduction




1.Introduction








1.Introduction/1.4 UMTS technical overview UMTS general architecture

Core network (CN)it provides support for thenetwork features andtelecommunication services. It isconnected to external CSnetworks or PS networks.

Radio Access network (RAN)it comprises roughly thefunctions specific to the accesstechnique.3 different RANs are foreseen:

•UTRAN (UMTS Terrestrial RAN)•MSS (Mobile Satellitecomponent)•BRAN (Broadband RAN)

User E ui ment (UE)

Iu

RAN

UE

Uu

CN Core Network RAN Radio Access Network UE User Equipment

CN

CS networks(PSTN, ISDN..)

PS networks(Internet…)

d i S h i l i




1.Introduction/1.4 UMTS technical overview UMTS Cellular System

UMTS consists of a set of hierarchical cells, but the multiple accesstechnique is completely different from GSM.

GSMUsers are separated in

frequency (FDMA) and in time(TDMA)

UMTSUsers are separated with codes

(CDMA)

1 I t d ti /1 4 UMTS t h i l i




1.Introduction/1.4 UMTS technical overview UMTS duplex modes

Downlink

Uplink FDD mode

Code and Frequencyorthogonality

f1

f2

5 MHz channel

15TS

5 MHz channel

TDD mode

Code and Timeorthogonality

Uplink & Downlink

...

...

1 I t d ti /1 4 UMTS t h i l i




1.Introduction/1.4 UMTS technical overview UMTS Frequency

allocations

TDD FDD MSS TDD

1900 1980 2010 20251920

MSSFDD2110 2170 2200

FDD: Frequency Division Duplex TDD: Time Division DuplexMSS: Mobile Satellite System

Uplink Downlink



1.Introduction




QUIZ! (2)

C. Which of these radio interfaces belongs to IMT-2000?

1/ CDMA One 2/ UMTS FDD 3/ UMTS TDD 4/ CDMA 2000 5/ EDGE

D. What is the organisation responsible for UMTS standardization?

1/ 3GPP 2/ 3GPP2 3/ ETSI 4/ ARIB 5/CWTS

E. What is the bandwidth of a CDMA carrier in UMTS?

1/ 200 kHz 2/ 1 MHz 3/ 5 MHz

F. Are the following statements about UTMS duplex modes True or False?

1/ FDD is similar to the GSM duplex mode

2/ TDD use the same frequencies as FDD

3/ FDD is better suited for asymmetric traffic

4/ TDD will come later




2.

Services provided



2 Services provided/2 1 UMTS service principles




2. Services provided/2.1 UMTS service principles

What is a service?

E.g speech,file transfer,emails...

E.g datatransfer at9,6 kbps, intransparentmode,with turbocode...

UTRAN CN CNGateway

TE

UMTS Bearer Service External Bearer ServiceUMTS Bearer Service

Radio Access Bearer Service

(RAB)CN Bearer

Service

BackboneBearer Service

Iu Bearer Service

Radio Bearer Service

Radio Physical

Bearer Service

PhysicalBearer Service

Uu Iu

Teleservice

... ...

TE/MTNode




hi d i




Third party: serviceprovider

Tele-services will not be standardised so as todifferentiate between operators and providers of applications.UMTS offer new opportunity for content and serviceproviders

Today’s 1:1 customer-operator relationship

Tomorrow’s situation?

OperatorContracted Content providers

Contracted Service providers

Contracted Service providers

Operator


Vi t l H E i t




Virtual Home Environment(VHE)

The Virtual Home Environment (VHE) is an important portabilityconcept of the 3G mobile systems.

• it enables end users to bring with them their PersonalService Environment (PSE) whilst roaming between networks,

• and also being independent of terminal used.

• "same look and feel" wherever you are

The PSE is defined in terms of one or more User Profiles (list of subscriptions, associated preferences, terminal interfacepreferences, …)


S i A hit t



©Alcatel University -

8AS 90171 0004VT ZZA Ed. E.A.U

Service Architecture

VHE concept is based on the standard mechanisms of ServiceCapability Servers which allow Service Capability Features. Thelatter are carried through standard interfaces in order to support

Tele-services adapted to the Service Capabilities of the networkand user equipment.

Service Layer

Service Capability Features

SATCAMEL MExEService Capability Servers GSM/GPRS/UMTS

Standardizedinterfaces

Network Layer

Tele-services(terminal equipment functions,

Operator transmission capabilities)

Bearer Services

Fixed


L t’ L k f th t




Let’s Look for the nearestrestaurant

Choose your preferences:

- type of restaurant:French

- type of payment: credit card

...

This service is built from the following service capabilityfeatures:call set-up & authorisation (CAMEL for services in roaming after

authentication phase with SAT),Map display on the phone : SAT and MExECall the restaurant by Push Service : MExEReservation with VISA card number : secured transaction withMExEBilling of the service : CAMEL

Restaurant Paul Bocuse69660 Collonges-au-Mont-d'or

2. Services provided




2.12.1 UMTS service principlesUMTS service principles

2.22.2 UMTS Bearer servicesUMTS Bearer services

2.32.3 Tele-services Tele-services

2.42.4 UMTS TerminalsUMTS Terminals

2. Services provided/2.2 UMTS Bearer Services

Bearer services




Bearer servicescharacterization

Bearer services are characterized by a set of end-to-endcharacteristics with requirements on QoS, always consideredpoint-to-point.

Bearer services provide the capability for information transferbetween access points and involve only low layer functions.

Each bearer service is characterized by its requirements:

• transfer information: connection oriented or connectionless,traffic type (guaranteed/constant bit rate, nonguaranteed/variable…), traffic characteristics (uni-directional,

bi-directional, multicast…), priority• quality characteristics: maximum transfer delay, delayvariation, bit error ratio, data rate.

This set of requirements are called QoS parameters.

Exam le : several active radio bearer services can be handled


Bearer QoS requirements




Bearer QoS requirements

• negotiable: QoS offer on demand

• provide a wide range of QoS levels

• dynamic behaviour: It shall be possible to negotiate (re-negotiate) the characteristics of a bearer service at session orconnection establishment (during an on going session orconnection).

• support of asymmetric nature between uplink and downlink

• supply of bearer services without wasting resources on theradio and network interfaces.


Bearer Supported bit rates




Bearer Supported bit rates

The only limiting factor for satisfying application requirementsshall be the cumulative bit rate per mobile termination at a giveninstant in each radio environment:

•At least 144 kbps in rural outdoor radio environment (witha maximum speed of 500 km/h)

•At least 384 kbps in urban or suburban outdoor radioenvironments (with a maximum speed of 120 km/h)

•At least 2048 kbps in indoor or low range outdoor radioenvironment (with a maximum speed of 10 km/h)

Theses performances decrease:

- when the speed of the user increases

- when the load of the network increases









2. Services provided/2.3 Tele-services

Typology




Typology

Locationservices

• Traffic Conditions•Itineraries•Nearest Restaurant,

Cinema, Chemist,Parking;, ATM ...

Fun•Games (Hangman, Poker, Quiz, …)•Screen Saver•Ring Tone•Horoscope•Biorhythm

MediaAlways-on

M-commerce

Mobile Office•Voice (!)•E-mail•Agenda•IntraNet/InterNet•Corporate Applications

•Database Access

Transportatio

n•Flight/trainSchedule

•reservation

Verticalapplication

• TrafficManagement

•Automation•Mobile branches

•Health

Music•Downloading of

music files or

video clips News(general/specific)•International/National News•Local News•Sport News•Weather•Lottery Results•Finance News•Stock Quotes•Exchange Rates

Physical•on-line shopping•on-line food

Nonphysical

•on-line Banking• Ticketing•Auction•Gambling•Best Price•e-Book

Directories• Yellow/White Pages• International Directories•Operator Services


QoS classes




QoS classes

w 4 classes have been identified:t conversational

• AMR speech service

• Video telephony

– CS: H324

– PS: H323t streaming

t interactive• Web-browsing

• location based services

t background• e-mail delivery

• SMS ...

Delaysensitiv

e

+

-

DataIntegrit

ysensitiv

e

-

+

2. Services provided/2.3 Tele-services P f




Performance

QoS of teleservices depends not only on UMTS network, but alsoon applications, terminals and external networks.

From a user’s perspective it is more relevant to speak of delayrather than bit rate:

Error tolerant

Error intolerant

Conversational

delay <<1 sec

Interactive

delay<1 sec

Streaming

delay <10 sec

Backgrounddelay >10 sec

Conversationalvoice and video

Streaming audioand video

Fax

E-mail arrival

notification

E-commerce,

WWW browsingTelnet,interactive games FTP, still image,paging

Voice messaging


Defining charging




Defining chargingprinciples

• How will billing be performed: by time? by volume? by numberof connections?

• If billing is performed by volume, what will be an easy way toexplain to the customer what a “1 Mbyte of data” is?

• What will happen in case of handover between GSM and UMTS?

• What about roaming? Prepaid services?

• QoS depends directly on the load of the network. A trade-off must be found between users. Customers who pay more mighthave higher priority or better QoS (depending of the operator’sstrategies). Billing for a given service might depend on the QoS.

2. Services provided/2.3 Teleservices

Location based services




Location based services

Teleservices will depend on the strategy and on the imaginationof operators and content providers.

The key point is likely to be a fast access to information and anappropriate filtering of the user location data.

the UMTS killer application is likely be a location based service

Example of location based services : look for an hotel, consultyellow pages, get local traffic situation or weather report,...

Limitation: location information could be a risk for privacy.









2. Services provided/2.4 UMTS terminals

User Equipement (UE)




User Equipement (UE)

User Equipment(UE)

Cuinterface

MobileEquipmen

t

(ME)

UICC

USIM

USIM2

1

GSM

access

SIM

GSM/GPRS

terminal

2. Services provided/2.4 UMTS terminals

Range of terminals




g

There will be a wide range of terminals depending of the type of application (speech, video, games, dual...), the mode (UMTS/GSM,UMTS/DECT...)

Consumer Electronics

Games AudioImage

Automotive / Telematics

New

inte

rfaces

Data / IT

E-Commerce

Domestic G P S

Integrated approach:1 handset able to perform allfunctions. Most of the concept

phones today.

Distributed approach:1 handset for voice & WAP, or voiceonly and a Bluetooth connection to

other devices (headset, camera...).


QUIZ!




Q

A. True or False? The tele-services...

1/ are used for example to make a call, to access yellow pages, on-line banking...

2/ are mapped on bearer services

3/ will be standardized by 3GPP

B. True of False? The VHE...

1/ is a portability concept of 3G mobile systems

2/ will enable to keep the same environment when roaming between mobile andfixed networks

3/ will be adapted to the terminal capabilities

4/ will use proprietary interfaces


QUIZ!




Q

C. True or False? A bearer service can support for one user:

1/ 2 Mbps at a speed of 120 km/h

2/ 2 Mbps in a high loaded cell

3/ 2 Mbps at 3 km away from the base station

4/ Asymmetric traffic

5/ Variable traffic

D. True or False? Location based services...

1/ are services only available in some areas (city centers...)

2/ are services related to the location of the user

3/ can locate the mobile phone with an accuracy of about 50 m


QUIZ!




E. True or False? A UICC (UMTS integrated Circuit Card)...

1/ has the same size as a GSM SIM card

2/ can not be used in a GSM terminal

3/ can be used in an UMTS terminal and provide access to GSM network

4/ is linked with the UMTS terminal via a proprietary interface

5/ may provide access to UMTS networks of different operators

F. UMTS services have been announced to come later than initiallyscheduled because of non availability of UMTS terminals in volume: canyou find some reasons which makes it quite complex to design UMTSterminals?



3. UMTS System Description

3 views of the system




Entities

Bearers

Protocolstacks

Logical architecture Protocol architecture

Call scenario





3.1 Logical architecture

3.2 Protocol architecture

3.3 Call scenario

Entities

Bearers

Protocolstacks

3. UMTS System Descript./3.1 UMTS logical

architecture UMTS l i l A hi




UMTS logical Architecture

RNS

RNC

RNS

RNC

Core Network

Node B

Iu-CS Iu-PS

Iur

Iub IubIub Iub

CS-Service

Domain

PS-Service

Domain

Iu-reference

point

Iu-PS Iu-CS

Node_B Node B Node B Node B

UU

CN

IU

UTRAN

UE

Uu-reference

point


architecture CN l i l hit t




CN logical architecture

UMTS Core Network for Release 99

PLMNPSTN / ISDN

ExternalIP

Network

2G/3GSGSN

HLR VHE

GSM BSSBSC

Iu (PS)

Iu (CS)

2G/3GMSC

RNC IPBackbone

2G/3GGGSN

A

Gb

UTRAN

2G/3GGMSC

EIR AuC


architecture UTRAN logicalA hit t




Architecture

RNC

It is the intelligent part of the UTRAN:- radio resource management (code allocation, congestion control,admission control)- radio mobility management- macro-diversity handling (soft HO)- control of Node-Bs

Node-BA Node-B can be composed of several cells and performs:- radio transmission handling- macro-diversity handling (softer HO)

RNS

RNC

RNS

RNC

Node B

Iur

Iub IubIub Iub

Node_B Node B Node B Node B


architecture Soft Handover (1)




5

DS

6

S

21

Core Network

IubIub

Iu

Iub

Iur

Iu

Iub

RNC1 RNC2

NodeB1 NodeB2 NodeB3 NodeB4

3 4

S D


architecture Soft Handover (2)




The role of an RNC (Serving or Drift) is on a per connection basisbetween a UE and the UTRAN:

Serving RNC: provide Iu UE-CN connection

Drift RNC: supports Serving RNC by providing radio resources

The recombination of the signal is performed in Serving RNC (inNode B for softer HO) and in UE using a RAKE receiver.

Soft HO is highly recommended in UMTS system: about 30 to 40%

of mobiles are in macro-diversity mode in IS-95.


architecture UMTS logicalInterfaces




Interfaces

Open Interfaces

The functional split for the UMTS components (UE, Node-B, RNC...)are clearly specified, but the internal architecture andimplementation issues are left open (it is up to the manufacturer).

However all the interfaces (Cu, Uu, Iub, Iur, Iu-CS, Iu-Ps) have

been defined in such a detailed level that the equipment at theendpoints can be from different manufacturers.

“Open Interfaces” aim at motivating competition betweenmanufacturers.

Physical implementation of Iu interfacesEach Iu Interface may be implemented on any physicalconnection using any transport technology.

ATM will be provided in the R99 release and IP is foreseen infurther releases







3.3 Call scenario

Entities

Bearers

Protocolstacks

3. UMTS System Descri./3.2 UMTS protocol

architecture Access stratum andNon Access Stratum




Non Access Stratum

Interchanges between entities is applied on a peer-to-peerprinciple.

Each entity provides services to entities of upper layers throughService Access Points (SAP).

SAP

UTRAN CN

Access Stratum(AS)

Non-Access Stratum (NAS)

Uu Iu

IuProtocols

(2)

IuProtocols

(2)

RadioProtocols

(1)

UE

RadioProtocols

(1)


architecture Non Access Stratum




CM/MM

Iu Protocols

IuProtocol

s

RadioProtocol

s

CM/MM

Radio ProtocolsMSC

UE

Iu-CS

Uu

NAS

AS

CStraffic

CStraffic

PStraffic

PStraffic

Iu Protocols

SGSN

Iu-PS

SM/GMMUTRAN

SM/GMM


architecture Access Stratum:radio protocols




MAC

RLC

PDCP BMC

radio protocols

Phys

MAC

RLC

Phys

Uu Iub

ACCESS STRATUM (AS)

UE Node B RNC

U s e r p l a n e

C o n t r o l p

l a n e

PDCP BMC

RRC

NON ACCESS STRATUM (NAS)

RRC

2. Web browsing (from/to Iu-PS)

2

4. User authentication (NAS signalling)

4

1. Speech (from/to Iu-CS)1

5. Initial access ( RRC Connection Establishment)

3. Localweather forecast

(SMSCell

Broadcas

t )

3

Iu

protocols

Iu

protocols


architecture Access Stratum: Iuprotocols




protocols

RNCNode-B

SGSN

MSC

NBAP

Iu-CS

Iu-PSRNC

Iur

Radio

NetworkLayer

Transport

Network

Layer

Physical Layer

SignalingBearer(s)

SignalingBearer(s)

DataBearer(s)

ALCAP

ApplicationProtocol DataStream(s)

Transport NetworkControl Plane

TransportNetwork User

Plane


Plane

ControlPlane

User Plane The same generalprotocol model is

applied for all Iuinterfaces:

ApplicationProtocol:

- NBAP for Iub

- RNSAP for Iur

- RANAP for Iu-CSand Iu-PS

Iub

RNSAP

RANAP







3.3 Call scenario

Entities

Bearers

Protocolstacks

3. UMTS System Description/3.3 Call Scenario

Radio Access Bearer (RAB)




“The RAB provides confidential transport of signaling anduser data between UE and CN with the appropriate QoS”.

UTRAN

UE

UMTS Bearer

UMTS Bearers

RABs (mapped on Radio & Iu Bearers)

CN-CS

CN-PS

Radio Bearers Iu Bearers

RAB

RAB

RAB

RAB

UMTS Bearer

UMTS bearerservices

3. UMTS System Description/3.3 Call Scenario Establishment of a call




Inside the UTRAN

No more distinction between CS and PS part: all data are mappedon RAB.

But the RAB characteristics (delay, bit rate…) may not be the

same for CS and PS part.

UTRAN has the total freedom to configure the radio bearersaccording to the required RAB attributes (ie QoS).

3. UMTS System Description/3.3 Call Scenario Example : CS call

establishment




establishment

Request for service(RRC) (RANAP)

Uu

Authentication and Ciphering / Integrity

Alert and Connect

Establishment of Resources (RAB + Radio Bearer)

Setup

Connection to UTRAN(RRC Connection establishment)

IuUE UTRAN CN


QUIZ!




A. Put the correct words in the spaces on the figure below

...

...

...

...

...

... ... ... ...

......

...

... ...

CS networks(PSTN, ISDN)

PS networks(internet)

...




4.

WCDMA for UMTS

4. WCDMA for UMTS





4.24.2 Spread Spectrum modulationSpread Spectrum modulation

4.34.3 Code Division Multiple AccessCode Division Multiple Access

4.44.4 Rake ReceiverRake Receiver

4.54.5 Power ControlPower Control

4.64.6 Soft HandoverSoft Handover

4.74.7 Typical coverage and capacity values Typical coverage and capacity values

4. WCDMA for UMTS/ 4.1 Context From military to civil

modern radio-




modern radiocommunications

Early 70’s CDMA developed for military field for its great qualities of privacy(low probability interception, interference rejection)

1996CDMA commercial launch in the US

This system called IS-95 or cdmaOne was developed byQualcomm and has reached 50 million subscribers worldwide

2000IMT-2000 has selected three CDMA radio interfaces:- WCDMA (UTRA FDD)

- TD-CDMA (UTRA TDD)- CDMA 2000

In the following material we will only refer to WCDMA (UTRA FDD)

4. WCDMA for UMTS/ 4.1 Context Why CDMA?




CDMA is very attractive:

• Better spectrum efficiency than 2G systems

• Suitable for all type of services (circuit, packet) and for multi-services

• Enhanced privacy

• Evolutionary (linked with progress in signal processing field)

BUT:

• Complex system: not easy to configure and to manage

• Unstable in case of congestion

4. WCDMA for UMTS











4. WCDMA for UMTS/ 4.2 Spread Spectrum Modulation

A code as a shell




A code as a shellagainst noise

The letter ‘A’ represents the signal to transmit over the radiointerface.

At the transmitter the height (ie the power) of ‘A’ is spread, whilea color (i.e a code) is added to ‘A’.

At the receiver ‘A’ can be retrieved with knowledge of the code,even if the power of the received signal is below the power of noise due to the radio channel.

Radio channel

Receiver Transmitter

Spreading

Noise

Despreading

4. WCDMA for UMTS/ 4.2 Spread Spectrum

Modulation Spectrum spreading




At the transmitter the signal is multiplied by a code whichspreads the signal over a wide bandwidth while decreasing the

power (per unit of spectrum).

At the receiver it is possible to retrieve the wanted signal bymultiplying the received signal by the same code: you get apeak of correlation, while the noise level due to the radio channelremains the same, because this is not correlated with the code.

The spectrum spreading permits transmission of a signal belowthe noise level and makes the signal very hard to detect.

Spectrum spreading makes CDMA very secure.

f

P

f

P

f

P

f

P

Noiselevel

Radio channel

Spreading De-spreading


Modulation Transmission Chain




Air Interface

The narrowband data signal is multiplied bit per bit by a codesequence: it is known as “chipping”.

The chip rate of this code sequence is much higher than the bitrate of the data signal: it produces a wideband signal, also calledspread signal.

At the receiver the same code sequence in phase should be usedto retrieve the original data signal.

Modulator Demodulator

Code Sequence

Data Data

Code sequence

NB-Signal WB-Signal NB-SignalWB-Signal


Modulation Spreading factor




Signal 1 0 0 (bits)Spreading 1111 0000 0000 (chips)Code 0101 0101 0101Tx signal 0101 1010 1010

Rx signal 0101 1010 1010

Code 0101 0101 0101Despreading 1111 0000 0000Signal 1 0 0

(In this case, each bit of the signal is spread over 4 chips. Thespreading factor is 4)

Spreading makes CDMA adequate for services withvariable bit rates.

Radio channel


Modulation Processing Gain




The Processing Gain is the gain you have at the receiver by thedespreading of the signal (peak of correlation). It enablestransmission of the signal below the noise level.

A high bit rate signal needs more power to cross the noiselevel by de-spreading.

f

P

W

ProcessingGain

Rb

De-spreading

=

b R

W Log 1010GainProcessing

4. WCDMA for UMTS




4.14.1

ContextContext







4. WCDMA for UMTS/ 4.3 Code Division Multiple

Access One-cell reuse




The area is divided into cells, but the entirebandwidth is reused in each cell (frequencyreuse of one)

> Inter-cell interference

> Cell orthogonality is achieved by codes

The entire bandwidth is used by each userat the same time

> Intra-cell interference

> User orthogonality is achieved by codes


Access Multiple access (1)




All the users transmit on the same 5 MHz carrier at the same time

and interfere with each over.

At the receiver the users can be separated by means of (quasi-)orthogonal codes.

Transmitter 2

Spreading 1

Spreading1

Spreading 2 Receiver

Radio Channel Transmitter 1

The receiver aims at receiving Transmitter 1 only.




Access Spreading:

Channelization and




Channelization and

scrambling

2chc

3chc

1chc

scrambling c

The channelization code (or spreading code) is signal-specific:the code length is chosen according to the bit rate of the signal.

The scrambling code is equipment-specific.

airinterfac

eModulator


Access Channelization codes

(spreading codes)




(spreading codes)

The channelization codes are OVSF (Orthogonal VariableSpreading Factor) codes:

• their length is equal to the spreading factor of the signal: theycan match variable bit rates on a frame-by-frame basis.

• orthogonality enables to separate physical channels:UL: separation of physical channels from the same terminalDL: separation of physical channels to different users within onecell

SF = 1

C ch,1,0 = (1)

C ch,2,0 = (1,1)

C ch,2,1 = (1,-1)

C ch,4,0 =(1,1,1,1)

C ch,4,1 = (1,1,-1,-1)

C ch,4,2 = (1,-1,1,-1)

C ch,4,3 = (1,-1,-1,1)

SF = 4SF = 2 SF = 8

The code tree is shared byseveral users (usually one codetree per cell)

4. WCDMA for UMTS/ 4.3 Code Division MultipleAccess

Scrambling codes




The scrambling codes provide separation between

equipment:• UL: separation of terminalsNo need for code planning (millions of codes!)

There are 214 long and 214 short scrambling codes in uplink

• DL: separation of cellsNeed for code planning between cells (but trivial task)

There are only long scrambling codes in downlink(512 to limit the code identification during cell searchprocedure)

The long scrambling codes are truncated to the 10 ms framelength.

Only one DL scrambling code should be used within a cell.

Another scrambling code may be introduced in one cell if

4. WCDMA for UMTS











4. WCDMA for UMTS/ 4.4 Rake ReceiverRake Receiver principle (1)




In a CDMA system there is a single carrier which contains all usersignals.

Decoding of all these signals by one receiver is only a question of signal processing capacity.

A Rake receiver is capable to decode several signalssimultaneously in the so called “fingers” and to combine them inorder to improve the quality of the signal or to get severalservices at the same time.

A Rake receiver is implemented in mobile phones and in base

stations.

A Rake receiver can provide:- multi-service (via handling of multiple physical channels that arecarrying the services)- soft handover

4. WCDMA for UMTS/ 4.4 Rake Receiver Rake receiver principle (2)

Delay Adjustment




The components of the multi-code signal are demodulated inparallel each in one “finger” of the Rake Receiver.

The outputs of the fingers:• can provide independent data signals• can be combined to provide a better data signal(s)

Delay 1Code Sequence 1

Code Sequence 2 or 3

Code Sequence 2

Delay 2

Delay 3

Data 2

1st Finger

2nd Finger

3rd Finger

Data 1

Multi-codesignal

Delay Adjustment

4. WCDMA for UMTS/ 4.4 Rake Receiver Rake receiver

and multi-service




As a first approach, we can say:

One service, one code! (*)

Multimedia receiver Transmitter

Spreading 1 Despreading 1

Radio ChannelSpreading 2

Despreading 2

>> Which codes make it possible to>> Which codes make it possible toseparate the two signals at theseparate the two signals at thereceiver?receiver?

4. WCDMA for UMTS/ 4.4 Rake Receiver Rake Receiver

and soft handover




Soft handover is possible, because the two mobile stations usethe same frequency band. The mobile phone need only onetransmission chain to decode both simultaneously.

Base Station 2

Spreading 1

Despreading 1&2

Spreading 2 Mobile phone

Radio ChannelBase station 1

>> Which codes make it possible>> Which codes make it possibleto separate the two signals at theto separate the two signals at thereceiver?receiver?


and path diversity (1)




Natural obstacles (buildings, hills…) cause reflections, diffractionsand scattering and consequently multipath propagation.

The delay dispersion depends on the environment and is typically:

• 1 µs (300 m) in urban areas

• 20 µs (6000 m) in hilly areas

The delay dispersion should be compared with the chip duration0,26 µs (78 m) of the CDMA system.

If the delay dispersion is greater than the chip duration, the

multipath components of the signal can be separated by a RakeReceiver.

In this case, CDMA can take advantage of multipathpropagation.


and path diversity (2)




Dispersion > Chip duration The Rake Receiver can provide path diversity to improve the quality of the signal.


Spreading Despreading

Direct path

Reflected path


Spreading Despreading

Direct path

Reflected path

Dispersion <Chip duration

The Rake Receiver cannot provide path diversity.

>> Which codes make it>> Which codes make it

possible to separate thepossible to separate thetwo signals at thetwo signals at thereceiver?receiver?

4. WCDMA for UMTS



4. WCDMA for UMTS/ 4.5 Power Control Open Loop




If UE receives a STRONG DLsignal,then UE will speak low.

Node

BNode

B

1

2

1

2

If UE receives a weak DLsignal,then UE will speak LOUD.

Problem:fading is not correlated on UL and DL due to separation of UL andDL band.

Open loop Power Control is inaccurate.

Open loop power control

4. WCDMA for UMTS/ 4.5 Power Control Closed Loop

Closed loop power control




The Node-B controls the power of the UE (and vice versa) byperforming a SIR estimation (inner loop).

The RNC controls parameters of the SIR estimation (outer loop).

This SIR estimation is performed each 0,66 ms (1500 Hzcommand rate).

Closed loop Power Control is very fast.

Node

B

p p

...

”Power down”

”Power up”

”Power down”

”Power ...”

SIR estimation

SIRestimation

SIRestimation

SIRestimation

RNCSIR

target

4 14 1 ContextContext

4. WCDMA for UMTS











4. WCDMA for UMTS/ 4.6 Soft HandoverSoft Handover (1)




Node

B

NodeB

SoftHO

Softer HO

RNC

Node

B

4. WCDMA for UMTS/ 4.6 Soft Handover Soft Handover (2)




Why do we need soft HO?Imagine that a UE penetrates from one cell deeply into anadjacent cell:> it may cause near-far problem> hard HO is not a good solution, because of the need for thehysteresis mechanism

Additional resources due to soft HO:- Additional rake receiver in Node-B- Additional Rake Fingers in UE- Additional transmission links between Node-Bs and RNCs

Soft HO provides Diversity (also called Macro-Diversity),

but requires more network resource.

4. WCDMA for UMTS/ 4.6 Soft Handover Soft Handover (3)

w Soft Handover execution:




w Soft Handover execution:

t Soft Handover is executed by means of the following procedures• Radio Link Addition (FDD soft-add);

• Radio Link Removal (FDD soft-drop);

• Combined Radio Link Addition and Removal.

t The cell to be added to the active set needs to have informationforwarded by the RNC:

• Connection parameters (coding scheme, layer 2 information, …)

• UE ID and uplink scrambling code,

• Timing information from UE

t The UE needs to get the following information

• Channelization & scrambling codes to be used

• Relative timing information (Timing offset based on CPICH synchro)

4. WCDMA for UMTS












4. WCDMA for UMTS/ 4.7 Typical coverage and capacityvalues

Radio dimensioning process:What’s new?

Market perspective




p p

Mobile data market forecastMarketing inputs

Multi-service environmentVoice+dataVariable bit rate

Different QoSAsymmetric traffic

New radio technologyW-CDMA Capacity

Coverage Quality

4. WCDMA for UMTS/ 4.7 Typical coverage and capacityvalues Concentric coverage

The coverage is determined by the uplink range, because the




Service Speech

12 kbps

Packet data

144 kbps

Packet data

384 kbps

Cell radius

(uplink limited)

transmission power of the terminal is much lower than that of thebase station.

UE TransmitPower

21 dBm (126mW)

24 dBm (251mW)

R1 ≈ 3 km R2 ≈ 2 km R3 ≈ 1,5 km

in suburban area

R1

R2

R3


Ways of improving coverage

AMR speech Codec




AMR speech Codecit enables to switch to a lower bit rate if the mobile is moving out of the cell coverage area: it is a trade-off between quality andcoverage.

Multipath diversityit consists of combining the different paths of a signal (due to

reflections, diffractions or scattering) by using a Rake Receiver.Multipath diversity is very efficient with W-CDMA.

Soft(er) handoverthe transmission from the mobile is received by two or more basestations.

Receive antenna diversitythe base station collects the signal on two uncorrelated branches. Itcan be obtained by space or polarization diversity.

Base stations algorithmse.g. accuracy of SIR estimation in power control process


Soft capacity

The capacity is determined by the downlink direction, because:




- better receiver techniques can be used in the base station thanin the mobile station (but requiring more CPU power).

- the downlink capacity is expected to be more important than theuplink capacity because of asymmetric traffic.

The downlink capacity has two limitations:- the amount of interference in the air interfaceAdjacent cells share part of the same interference: there is anadditional capacity in a cell, if the number of users in theneighboring cells is smaller.

- the loss of code orthogonality The downlink codes originate from a single point and can besynchronized.But, after transmission over multipath channel, part of orthogonality is lost.


Parameters influencing capacity

The capacity depends on:the radio environment (rural suburban indoor)




- the radio environment (rural, suburban, indoor)- the terminal speeds- the distribution of the terminals- the load of the cell: trade-off capacity/coverage (breathing cells)

High loaded cell

High DL interference levelDL data throughput 660 kbps(per carrier per sector)

High loaded cell

Low DL interference levelDL data throughput 1440 kbps(per carrier per sector)

4. WCDMA for UMTSQUIZ!

A. True or False? Spreading...




p g

1/ consists of increasing the power while decreasing the frequency bandwidth

2/ allows to transmit a signal with a S/N (Signal-to-Noise ratio) smaller than one

3/ enables to retrieve the coded signal at the receiver by using the same code inphase

4/ is used in FDMA system

B. Signal 1 has a bit rate of 12 kbps and a coding rate of 1/3, signal 2 has abit rate of 384 kbps and a coding rate of 1/2:

1/ Which spreading factor should be chosen for each of these signals?

2/ What is the processing gain for each of these signals?

4. WCDMA for UMTSQUIZ!

C. True of false? WCDMA...




1/ is also called UMTS FDD or UTRA FDD

2/ uses a 1 MHz bandwidth carrier

3/ has a chip rate of 3,84 Mchips/s

D. How many carriers are there per operator for WCDMA?

1/ 124 carriers 2/ 62 carriers 3/ 1 to 3 according to the country

E. True or false? A Rake Receiver

1/ can separate simultaneously two signals only if their codes are perfectlyorthogonal

2/ can separate simultaneously several signals of 2 different WCDMA carriers

3/ can take advantage of multipath propagation



5. UTRAN UTRAN role and principles

Layer 3




• To transfer traffic and control channels between UE and CN

- Common handling of packet-switched and circuit-switched data

- Protection of the user data on the air interface (providing of ciphering)

- Independence from the applied transport technology on the Iu interface

• To manage the radio mobility of the user

Full control of UE radio mobility with the use of the Iur interface which

makes it possible to perform soft HO even with 2 cells/Node-Bs belongingto different RNCs.

• To make efficient use of limited radio resources

Support of WCDMA specific Radio Resource Management (RRM)algorithms.

Layer 2

Layer 1

UE RNCNode BUu Iub

CN

5. UTRAN

Layer 3




5.15.1 From Radio Bearers to transport channelsFrom Radio Bearers to transport channels

5.25.2 Radio ProtocolsRadio Protocols

5.35.3 Iu ProtocolsIu Protocols

5.45.4 UE identifiers and UE statesUE identifiers and UE states

5.55.5 Signalling proceduresSignalling procedures

5.65.6 The Physical Layer (on the air interface) The Physical Layer (on the air interface)

5.75.7 Radio Resource Management (RRM)Radio Resource Management (RRM)

5.85.8 Mobility managementMobility management

Layer 2Layer 1

UE RNCNode B

5. UTRAN/5.1 From Radio Bearers to transportchannels

Situation




UTRAN CN CNGateway

UE

UMTS Bearer Service External Bearer Service

UMTS Bearer Service

Radio Access Bearer Service(RAB)

CN Bearer Service

BackboneBearer Service

Iu Bearer Service

Radio Bearer Service

Radio Physical

Bearer Service

PhysicalBearer Service

Uu Iu

Teleservice

... ...

UENode


Radio Bearers, logical andtransport channels

Control plane User plane




Transport Channels(Iur)/Iub/Uu

ControlLogical

Channels

User planeRadioBearers

RRC

RLC

MAC MAC

Phys. Phys.

PDCP BMC

TrafficLogicalChannels

Signalling

RadioBearers

NAS signallingTelephonTelephony speechy speech

Web browsingWeb browsing

SMS CellSMS CellBroadcastBroadcast

RRCRRCconnectionconnection

establishmeestablishmentnt

Transport Channels

...

UTRAN UE


Radio Bearers

Signalling Radio Bearers (SRB)




SRBs can carry:- layer 3 signalling (e.g. RRC connection establishment)- NAS signalling (e.g location update)

There can be up to 4 SRBs per RRC connection (one UE has one RRCconnection when connected to the UTRAN).

User Plane Radio Bearers

RABs are mapped on user plane RBs.

One RAB can be divided on RAB sub-flows and each sub-flow ismapped on one user plane RB.

e.g the AMR codec encodes/decodes speech into/from three sub-flows; each sub-flow can have its own channel coding.



5. UTRAN/5.1 From Radio Bearers to transportchannels Logical Channels (2)

UL ( )




/DL ( ) What type of information?

BCCH System control informatione.g cell identity, uplink interference level

PCCH Paging informatione.g CN originated call when the network does not know thelocation cell of the UE

CCCH Control informatione.g initial access (RRC connection request), cell update

DCCH Control information (but the UE must have a RRC connection)e.g radio bearer setup, measurement reports, HO

DTCH Traffic information dedicated to one UEe.g speech, fax, web browsing

CTCH Traffic information to all or a group of UEse.g SMS-Cell Broadcast

5. UTRAN/5.1 From Radio Bearers to transportchannels Why Transport

Channels?

A transport channel offers a flexible pattern to arrange




information on any service-specific rate, delay or coding beforemapping it on a physical channel:

• it provides flexibility in traffic variation

• it enables multiplexing of transport channels on the samephysical channel

Transport channels provide an efficient and fast flexibilityin radio resource management.

5. UTRAN/5.1 From Radio Bearers to transportchannels Structure of a Transport

Channel (1)

Transport Block:basic unit exchanged

Transport Format (TF): it may be changed every TTI. Each TF must belong to the Transport Format

( ) f h h l




168

168

168

168

168

360

360 bits

10 ms

Time Transmission

Interval (TTI):periodicity at which a

Transport Block Set istransferred by thephysical layer on theradio interface

10 ms

over transportchannels.

Set (TFS) of the transport channel

168

168

>> The system delivers one Transport Block Set to>> The system delivers one Transport Block Set tothe physical layer every TTIthe physical layer every TTI: what is the delivery bit: what is the delivery bitrate of the transport blocks to the physical layerrate of the transport blocks to the physical layerduring the first TTI?during the first TTI?

10 ms 10 ms




Example

576576

576 bits




576

576

576

576

576

576

576

576

40 ms

3. How many Transport Format(s) may be chosen for this transport channel?3. How many Transport Format(s) may be chosen for this transport channel?

4. Can you imagine why the transfer has been interrupted during the third TTI?4. Can you imagine why the transfer has been interrupted during the third TTI?

Static Part

TTI ?Coding scheme Turbo coding, coding rate=1/3CRC 16 bits

Dynamic Part Transport Block Size ? Transport Block Size Set 576*B (B=0,1,2,3,4)

1. Complete the1. Complete thetabletable

2.2. What is theWhat is thedelivery bit rate of delivery bit rate of the transport blocksthe transport blocksto the physical layerto the physical layerduring the first TTI?during the first TTI?


Transport Channels

C Ch l




Common ChannelsBroadcast Channel (BCH)

Dedicated Channels

Paging Channel (PCH)

Random Access Channel (RACH)

Forward Access Channel (FACH)

Dedicated Channel (DCH)

Common Packet Channel (CPCH)

Downlink Shared Channel (DSCH)UTRAN



5. UTRAN/5.1 From Radio Bearers to transportchannels Common Transport

Channels (2)

FACH: Forward Access Channel

A downlink transport channel that is used to carry control information It




A downlink transport channel that is used to carry control information. Itmay also carry short users packets. The FACH is transmitted over theentire cell or over only a part of the cell using beam-forming antennas.

The FACH uses open loop power control (slow power control).

>> In which case is it interesting to use beam-forming antennas? would>> In which case is it interesting to use beam-forming antennas? wouldit also be relevant to implement this feature for PCH?it also be relevant to implement this feature for PCH?

RACH: Random Access Channel

An uplink transport channel that is used to carry control information fromthe mobile especially at the initial access. It may also carry short userpackets. The RACH is always received from the entire cell and ischaracterized by a limited size data field, a collision risk and by the use

of open loop power control (slow power control).

>> Why is it interesting to carry short user packets on RACH in spite of >> Why is it interesting to carry short user packets on RACH in spite of limited data field and collision risk (instead of using a dedicatedlimited data field and collision risk (instead of using a dedicatedchannel)?channel)?


Common Transport Channels(3)

DSCH: Downlink Shared Channel

A downlink transport channel shared by several UEs to carry




A downlink transport channel shared by several UEs to carrydedicated control or user information. When a UE is using theDSCH, it always has an associated DCH, which provides powercontrol.

CPCH: Common Packet ChannelAn uplink transport channel that is used to carry long user datapackets and control packets. It is a contention based randomaccess channel. It is always associated with a dedicated channelon the downlink, which provides power control.

⇒ Transfer of signalling and traffic on a shared basis




MappingLogical⇔Transport Channels

Control Logical Channels Traffic Logical Channels




BCCH PCCH CCCH DCCH DTCH CTCH

BCH PCH RACH FACH DSCH CPCH DCH

Common Transport Channels DedicatedTransportChannels


MappingLogical ⇔ Transport

ChannelsControl Logical Channels Traffic Logical Channels




BCCH PCCH CCCH DCCH DTCH CTCH

BCH PCH RACH FACH DSCH CPCH DCH

Common Transport Channels DedicatedTransportChannels


Complete the gaps!

(1) … channels

are defined by what type of information (e g user data signalling




are defined by what type of information (e.g user data, signalling,system information...) is transported over the radio interface.

(2) … channels

are defined by how and with what characteristics (e.g type of coding, required transfer delay, required BER... ) data aretransferred over the radio interface.

(3) … channels

are defined by the mechanisms (e.g frequency, code, power,framing...) with which the data are transferred over the physicalresources of the air-interface.



5. UTRAN

Layer 3

Layer 2

Layer 1




yUE RNCNode B









5. UTRAN/5.2 Radio Protocols

Radio protocol stack

Control plane User plane

Bearers (called

RAB in user plane)Access Stratum

Non Access Stratum




Layer 3

Layer 2/MAC

Layer 1Transport Channels

SAP

c o n

t r o

l

c o n

t r o

l c o n

t r o

l

PHY

MAC

RRC

Logical Channels

Layer 2/RLC

Radio Bearers

RLC RLCRLC

RLCRLC

RLCRLCRLC

PDCPPDCP

BMC c o n

t r o

l

control

Layer 2/PDCPLayer 2/BMC

Physical Channels


Radio Resource Control(RRC)

RRC

BearersCall management

Radio mobility managementLayer 3




c o n

t r o

l

c o n

t r o

l

c o n

t r o

l

PHY

MAC

RRC

RLC

y gMeasurement control and reporting

Outer loop power controlRadio Bearers(control plane)

RRC is the brain of the radio interface protocol stack.

c o n

t r o

l

c o n

t r o

l

PDCP

BMC


PDCP and BMC protocols

PDCP (Packet Data Convergence Protocol)

- in the user plane, only for services from the PS domain




p , y- it contains compression methods

In R99 only a header compression method is mentioned (RFC2507).

Why is header compression valuable?

e.g a combined RTP/UDP/IP headers is at least 60 bytes for IPv6,when IP voice service header can be about 20 bytes or less.

BMC (Broadcast/Multicast Services)

- in the user plane

- to adapt broadcast and multicast services from NAS on the radiointerface

In R99 the only service using this protocol is SMS Cell BroadcastService (directly taken from GSM).


Radio Link Control (RLC)

Radio BearersR di B

Segmentation




TrafficLogical

Channels

Radio Bearers(user plane)

Radio Bearers(control plane)

RLC RLCRLC

RLCRLC

RLCRLCRLC

ControlLogical

Channels

g

Buffering

Data transfer with 3configuration modes:

- Transparent (TM)- Unacknowledged(UM)

- Acknowledged (AM)

Ciphering

RLC provides segmentation and (in AM mode) reliable datatransfer.

Layer 2/upper part


Medium Access Control(MAC)

Basic data transfer

Multiplexing of logical

TrafficLogical

Channels

ControlLogical

Channels




Transport Channels

(common and dedicated)

channels

Priority handling/Scheduling(TFC selection)

Reporting of measurementsCiphering

MAC can switch a common channel into a dedicated channel if higher bit rate is required (on request of L3-level).

MAC can change dynamically Transport Format (bit rate…) of eachtransport channel on a frame basis (each 10 ms) withoutinterchanging with L3-level.

MAC provides flexible data transfer.

MACLayer 2/

lower part


TFC selection in MACprotocol

Several transport channels can be time-coordinated to be multiplexed on a CCTrCH

before mapping on one physical channel (orif )

MAC

TFC selection




more if necessary).

e.g. DCH1 = {244}DCH2 = {0 ; 148}

DCH3 = {0 ; 148}

TFCS = { {244 ; 0 ; 0} , {244 ; 148 ; 0} , {244 ; 0 ;148} }

MAC selects TFC inside TFCS. There is one TFCS per CCTrCH.

>> Why is the combination {244 ; 148 ; 148} not>> Why is the combination {244 ; 148 ; 148} notpossible?possible?

TrCH multiplexing

DCH1 DCH2 DCH3

CCTrCH

Physical channelMapping

Physical Channel(s)

L1

Transport Format(TF)

Transport Format Set(TFS)

Transport Format Combination

(TFC)

Transport Format Combination Set(TFCS)




Exercise: MAC protocol (3)

7. RNTI (Radio Network Temporary Identity) is an UE identity assigned by UTRAN,when the UE is connected to the UTRAN . The parameter RNTI is included in theheader of each transport blocks in MAC-c/sh, but not in MAC-d : can you explain thereason?




reason?

8. The system can also multiplex transport channels: where does that take place?

9. What is the name of the channel on which several time-coordinated transportchannels can be multiplexed?

10. Which entity is responsible for TFC selection? TFCS allocation?

11. Is it possible to multiplex 2 FACHs (or more)? 2 DCHs (or more)? a FACH and aDCH?

12. Will the physical channel configuration be changed (e.g modification of

spreading factor) when MAC selects a new TFC inside TFCS?

13. MAC makes measurement reports to RRC: why is it necessary?

5. UTRAN

Layer 3

Layer 2

Layer 1UE RNCNode B




UE RNCNode B





5.55.5 Signaling proceduresSignaling procedures




5. UTRAN/ 5.3 Iu protocols

General model

The same general protocol model is applied for all Iu interfaces:

RadioNetwork

Application Data

Control

Plane

User Plane

1. What is the1. What is thepurpose of thepurpose of the




Application Protocols:

Layer

Transport

Network

Layer

Physical Layer

SignalingBearer(s)

SignalingBearer(s)

DataBearer(s)

ALCAP

ApplicationProtocol

DataStream(s)

Transport NetworkControl Plane


Plane


Plane

- NBAP for Iub interface- RNSAP for Iur interface- RANAP for Iu-CS and Iu-PS interfaces

p pp pseparationseparationbetween thebetween theRadio NetworkRadio NetworkLayer and theLayer and the

Transport TransportNetwork Layer?Network Layer?

2. Why is ALCAP2. Why is ALCAPprotocolprotocolnecessary?necessary?




5. UTRAN

?




p








?

5. UTRAN/5.4 UE identifiers and UE states

UE identifiers

2 types of UE identification on the radio interface:

• NAS identifiers




• NAS identifiers

- IMSI: International Mobile Subscriber Identity

- TMSI: Temporary Mobile Station Identity

They are used in the initial access CCCH message

• UTRAN identifier

- RNTI: Radio Network Temporary Identity

This is allocated by the UTRAN for each UE in connected mode

and used for inband identification in common transport channels(e.g FACH). The RNTI is not used outside the UTRAN.


UE states (1)

RRC Connection Releaseout of coverage




UE

detached

UE

in idle mode

UE

in connected

mode

RRC Connection Establishment

“just after switch on” process

Including Cell search procedure

Why is the idle mode necessary?Why is the idle mode necessary?




UE states (3)

Cell DCHUE

i idl

UE in

connected mode

Cell_DCH state

Signalling and traffic datadedicated to the UE( d DCCH d




Cell FACH

URA PCH

Cell PCHin idle

mode

(mapped on DCCH andDTCH respectively) arecarried on DCH transportchannel

Cell_FACH state

Signalling and traffic datadedicated to the UE(mapped on DCCH andDTCH respectively) arecarried on RACH (uplink)

and FACH (downlink)transport channels

Cell_DCH ⇒Cell_FACHNo traffic UL/DL at expiry of

timer 1

Cell_FACH⇒

Cell_DCHTraffic volume UL/DL toolarge


UE states (4)

Cell DCH

C ll PCH

UE

in idle

UE in

connected mode

Cell_PCH state

No transmission of signalling

and traffic data dedicated tothe UE (no DCCH and no




Cell FACH

URA PCH

Cell PCHin idle

mode

DTCH)

But the RRC connection is stillactive (UTRAN keeps RNTI forUE) and UE location at a cell

level.

- a DCCH (and possibly aDTCH) can be reestablishedvery quickly (this procedure isinitiated by sending a pagingsignal PCH)URA_PCH state

Very similar to cell_PCH state

UTRAN keeps the location of the UEat the URA level (set of UMTS cells)

Cell_PCH ⇒ Cell_FACH ⇒URA_PCH

Too many cell reselections

Cell_FACH⇒Cell_PCHNo traffic UL/DL at expiry of

timer 2

Cell/URA_PCH⇒ Cell_FACHIncoming DL or UL traffic


UE identifiers and UEstates:

complete the table!

CN UTRANUE States

UE Identifiers UE Location UE Identifier UELocation




UE Identifiers UE Location UE Identifier UE Location

idle mode IMSI, TMSI LA, RA

cell_DCH

cell_FACH

cell_PCH

connectedmode

URA_PCH

5 15 1 From Radio Bearers toFrom Radio Bearers to transporttransport channelschannels

5. UTRAN

Layer 3

Layer 2

Layer 1 UE RNCNode B




5.15.1 From Radio Bearers toFrom Radio Bearers to transporttransport channelschannels




5.55.5 Signaling proceduresSignaling procedures




5. UTRAN/5.5 Signaling procedures List of basic signalingprocedures

A. Broadcast of system information

B. PagingB1. Paging Type 1 (in idle mode or in cell_PCH or in URA_PCH states)B2. Paging Type 2 (in cell FACH or cell DCH states)




g g yp _ _

C. RRC ConnectionC1. RRC Connection Establishment (to cell_FACH and to cell_DCH states)C2. RRC Connection Release (in cell_DCH states)

D. Radio Link establishment

E. Direct Transfer

F. Control of RAB, RB, Transport Channel and Physical ChannelF1. RAB Establishment

F2. Physical Channel Reconfiguration

G. Soft HO (Radio Link Addition)



5. UTRAN/5.5 Signaling procedures

B. Paging

Paging is typically used at core network-originated call.

UE in idle mode The network will page the UE in LA (CS domain) or RA (PS domain)




UE is in connected mode

The network will page the UE:

- in the cell (in cell_PCH, cell_FACH, cell_DCH states)- in the URA (in URA_PCH state)

Paging Type 1: mapped on PCCH/PCH

Paging Type 2: mapped on DCCH/FACH or DCCH/DCH

>> Can you guess which Paging Type will be use in idle mode? in>> Can you guess which Paging Type will be use in idle mode? incell_PCH state? in cell_FACH state? in cell_DCH state? in URA_PCHcell_PCH state? in cell_FACH state? in cell_DCH state? in URA_PCHstate?state?


B1. Paging Type 1

UE 1 Node-B1

CNRNC 1 RNC 2Node-B2

RANAP

RANAP

1. PagingCN Domain Indicator, UE

identity, Paging cause

UE 2




RRC

RRC

2. Paging Type 1 (PCCH:PCH)

RRC

RRC

2. Paging Type1 (PCCH:PCH)

y, g g

RANAP

RANAP

1. Paging

Idem




C. RRC connection

RRC connection is established at the initial access

(after cell search procedure when the UE is camping on a cell).




After RRC connection establishment:

- UE will switch from idle mode to cell_FACH or cell_DCH states.

- UE will have a signalling link with UTRAN (on DCCH)

UE needs to establish a RRC connection prior to making :- voice call- location update

- measurement reporting...

5. UTRAN/5.5 Signaling procedures C1. RRC Connection

Establishment

Initial UE identity, Establishment cause, Initial UE capability1. RRC Connection Request ( CCCH:RACH )

UE Node-B RNC

RRC

RRC

2. Allocate RNTI, Select




3. Radio Link Establishment (see

Procedure D)

Initial UE identity, RNTI, capability update requirement, TFS, TFCS,

frequency, UL scrambling code, power control info

4. RRC Connection Setup ( CCCH:FACH ) RRC

RRC

Integrity information, ciphering information

5. RRC Connection Setup Complete ( DCCH:RACH or DCH ) R

RC

R

RC

Level 1 and Level 2parameters (e.g. TFCS,

scrambling code)

>> Can the UE send user information (e.g voice call) after completing>> Can the UE send user information (e.g voice call) after completing

this stage?this stage?

5. UTRAN/5.5 Signaling procedures C2. RRC Connection Release

(in cell_DCH state)UE Node-B

of DRNC

CNDRNC SRNCNode-Bof SRNC

RANAP RANAP

1. Iu Release

Command Cause

2. Iu Release




RRC

RRC

4. RRC Connection Release (DCCH:DCH )

Cause

RANAP

RANAP

Complete-

3. ALCAP Iu Bearer Release

RRC

RRC

5. RRC Connection Release Complete (DCCH:DCH )

-

6. Radio Link Deletion

7. Radio LinkDeletion

8. Radio Link Deletion

5. UTRAN/5.5 Signaling procedures D. Radio Link (RL)

Establishment for a DCH

Cell id, TFS, TFCS, frequency, ULscrambling code, power control info

Node-B RNC

Radio Link Setup Request NBAP

NBAP

Start RX




Signalling link termination, transportlayer addressing info

Radio Link Setup

Response

NB

AP

NB

AP

Downlink synchronisationIub-FP

Iub-FP

Uplink synchronisationIub-FP

Iub-FP

Start TX

ALCAP Iub Data Transport Bearer Setup

>> Are NBAP, ALCAP and RRC messages carried on the same transport bearers on>> Are NBAP, ALCAP and RRC messages carried on the same transport bearers on

Iub?Iub?

5. UTRAN/5.5 Signaling procedures E. Direct Transfer

The mechanism to transfer signalling from higher layers (NASsignaling) through messages of RRC protocol is called Direct

Transfer .UE CNSRNCNode-B




RANAP

RANAP

1. Direct Transfer

CN Domain Indicator,NAS PDU

RRC

RRC

2. Downlink Direct Transfer

(DCCH:FACH or DCH)

NAS message

RANAP

RANAP

2’. Direct Transfer

CN Domain Indicator,NAS PDU

RR

C

RR

C

1’. Uplink Direct Transfer

(DCCH:RACH or DCH)

CN node indicator, NAS message

>> Can you mention>> Can you mentionsome examples of use of some examples of use of

Direct Transfer Direct Transfer ??

5. UTRAN/5.5 Signaling procedures F. Control of RAB, RB,

Transport and PhysicalChannels These procedures take place after RRC connection establishment:

the UE is either on cell_FACH or cell_DCH state.

A RAB is mapped on one or more RB(s).




A RB establishment consists of:

- performing admission control (see RRM: Radio ResourceManagement)

- setting parameters describing RB processing in layer 2 (e.g TFS, TFCS) and in layer 1 (codes, power control)

RAB and RB can be reconfigured during an active connection.

The transport channels and physical channels parameters are

included in the RB but can also be reconfigured separately withtransport and physical channel dedicated procedures (Transport Channel Reconfiguration and Physical Channel Reconfiguration).

5. UTRAN/5.5 Signaling procedures F1. RAB Establishment

UE CNRNCNode-B

RANAP

RANAP

1. RAB Assignment

Request

RAB parameters, Userplane mode, TransportAddress, Iu Transport

association




association2. ALCAP Iu Data Transport Bearer Setup

3. Radio LinkEstablishment

(see Procedure D)

RRC

RRC

4. RB Setup (DCCH:FACH or DCH )

TFS, TFCS...

RRC

RRC

5. RB Setup Complete (DCCH:RACH or DCH

)

-

RANAP

RANAP

6. RAB Assignment

Response

-

>> Can the UE send user information (e.g voice call) after completing>> Can the UE send user information (e.g voice call) after completing

this stage?this stage?



5. UTRAN/5.5 Signaling procedures G. Soft HO

(Radio Link Addition)UE Node-B

of DRNCDRNC SRNC

RNS RNS2. RL Setup Request

1. Decision tosetup new RL




RRC

RRC

6. Active Set Update (DCCH:DCH )

-

AP APp q-

RRC

RRC

7. Active Set Update Complete (DCCH:DCH )

-

RNSAP

RNSAP

5. RL Setup

Response-

3. Radio Link Establishment(see Procedure D)

4. ALCAP Iur Data Transport Bearer Setup


EXERCICE

w Please complete the procedure diagrams on the followingslides by using the elementary procedure previously

described




w Duration :10 minutes

5. UTRAN/5.5 Signalling procedures Location Update

Find the missing procedurenames!

UE CNRNCNode-B

1. ...

0. “Just after switch on” process

UE in idle mode

UE detached

UE in connected mode




2. ...MM: Location Updating Request

MM: Authentication Request MM: Authentication Response

3. Security procedures

5. ...

4. ...MM: Location Updating Accept

UE in idle mode

5. UTRAN/5.5 Signalling procedures Mobile terminated call

Find the missing procedurenames!UE CNRNCNode-B

1. ...

2. ...

0. “Just after switch on” process




3. ... RR: Paging Response

MM: Authentication Request MM: Authentication Response

4. Security procedures

6. ...7. ...

CC: Alerting CC: Connect

CC: Connect Acknowledge

5. ...CC: Setup

CC: Call Confirm


5 25.2 Radio ProtocolsRadio Protocols

5. UTRAN

Layer 3

Layer 2

Layer 1 UE RNCNode B









5.75.7 Radio Resource management (RRM)Radio Resource management (RRM)


5. UTRAN/5.6 The Physical Layer

Physical Layer Process

Convolutional coding, Turbo coding

10 ms frame duration15 time slots

Channel Coding

Radio Frame Segmentation

Transport Channels




CCtrCH

DPDCH, DPCCH, PRACH...

Channelization codesScrambling codes

QPSK

Transport Channel Multiplexing

Physical Channel Mapping

Spreading

Modulation

Physical Channelsspread over 5 MHz bandwidth

Layer 1




Transport ChannelMultiplexing

DCH 1 DCH 2

Channel Coding Channel Coding




Two transport channels can be mapped onto the same physicalchannel (for one user).

Transport Channel Multiplexing

Physical Channel Mapping

One Physical Channel (or more if necessary)

CCTrCH


Physical channels

Physical channelsare defined by the mechanisms (e.g frequency, code, power, framing...)with which the data are transferred over the physical resources of the air-interface.

• Physical channels are defined mainly by:




- a specific carrier frequency

- a scrambling code

- a channelization code- start & stop instants (giving a time duration, measured in integermultiples of chips)

• Physical channels are sent continuously on the air interfacebetween start and stop instants.

• Physical channels are separated by means of quasi-orthogonalcodes (2 physical channels shall not have the same channelizationcode / scrambling code combination).


Uplink Physical Channels

Common Channels

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Associated with

Transport Channels




Dedicated Channels

Dedicated Physical Control Channel(DPCCH)

Dedicated Physical Data Channel (DPDCH) Associated with

Transport Channels

NOT associated withTransport Channels

NodeB


e.g. Uplink DPDCH/DPCCH

Pilot

Npilot bits

TPC

Data

Tslot = 2560 chips, 10*2k bits (k=0..6)

DPDCH

DPCCH

FBITFCI

NTFCI bits NFBI bits NTPC bits

Ndata bits




Slot #0 Slot #1 Slot #i Slot #14

f

T = 10 ms

1 Radio Frame

DPDCH carries the dedicated data generated at layer 2 (ie theDedicated Transport Channel DCH).

DPCCH carries the dedicated signalling of the physical layer,which is required to convey DPDCH. DPCCH is not visible above

the physical layer, it is not carried by any transport channels.

Under long scrambling code.




Downlink PhysicalChannels

Common Channels

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

Physical Downlink Shared Channel (PDSCH)

Associated with

Transport Channels




Dedicated Channels

Synchronisation Channel (SCH)

Page Indicator Channel (PICH)

Common Pilot Channel (CPICH)

Acquisition Indication Channel (AICH)

Dedicated Physical Control Channel

(DPCCH)

Dedicated Physical Data Channel (DPDCH)

NOT associated with

Transport Channels

Associated withTransport Channels

NOT associated with

Transport Channels

Node

B




e.g. Downlink PCCPCH

Data

18 bits

Tslot = 2560 chips , 20 bits

(Tx OFF)

256 chips




The Primary CCPCH carries the BCH, which provides system- andcell-specific information (e.g set of uplink scrambling codes)

The P-CCPCH is a fixed rate (30 kbps, SF=256) DL physicalchannel, which provide a timing reference for all physical channels

(directly for DL, indirectly for UL).CCPCH is scrambled under the Primary Scrambling code.


1 radio frame: Tf = 10 ms


e.g. CPICH (pilot)

Pre-defined symbol sequence


Tslot = 2560 chips , 20 bits = 10 symbols




CPICH (or Pilot or Beacon)

The pilot carries a pre-defined symbol sequence at a fixed rate(SF=256).

It is a reference:

- to aid the channel estimation at the terminal (time or phasereference)

- to perform handover measurements and cellselection/reselection (power reference)

1 radio frame: Tf = 10 ms


e.g SCH andthe cell search procedure

PrimarySCH

SecondarySCH

256 chips

2560 chips

acsi,0

acp

acsi,1

acp

acsi,14

acp

Slot #0 Slot #1 Slot #14




SCH (Synchronisation Channel)It can be detected by the UE just after switch on, as the SCHconsist of a 256 modulated code sequence which is the same forevery cell in the system.

It is used by the UE in the cell search procedure to get the

(downlink) scrambling code of the cell.After cell search procedure, the terminal can read system and cell-specific BCH information.

One 10 ms SCH radio frame


MappingTransport⇔PhysicalChannels

BCH

PCH

FACH

RACH

P-CCPCH Primary Common Control Physical Channel

S-CCPH Secondary Common Control Physical Channel

PRACH Physical Random Access Channel




CPCH

DSCH

DCH

PCPCH Physical Common Packet Channel

PDSCH Physical Downlink Shared Channel

DPDCH Dedicated Physical Data Channel

Physical channels not mapped on transport channels:

DPCCH Dedicated Physical Control Channel (uplink and downlink)

SCH Synchronisation Channel

CPICH Common Pilot Channel

PICH Page Indicator Channel

AICH Acquisition Indication Channel


Example 1: UL 64 kbps data(1)

In this example, a RB (Radio Bearer) is mapped (in RLC) on DTCHwhich is mapped (in MAC) on DCH.

The DCH has the TFS (Transport Format Set):

Transport block size 640 bits

Transport block set size 4*640 bits

CRC 16 bits




This example can be applied for ISDN service.

640 640#1 640

40 ms

CRC 16 bits

Coding Turbo coding, coding rate = 1/3

TTI 40 ms

640 640#2 640

640 640#3 640

640 640#4 640

640

640

640

640


Example 1: UL 64 kbps data(2)

640 16

2624

640 16

#1

#1

CRC640#4

#4

CRC640

Turbo coding R=1/3

Transport block

CRC attachment

TrBk concatenation

7872




What is the radioWhat is the radioframe length? Canframe length? Canyou deduce theyou deduce thespreading factorspreading factor(SF)?(SF)?

7884

Tail

12

#1

1971+NRM1

#4

To TrCh Multiplexing (see further)

#1 #4

1971 1971

Rate matching

1st interleaving

Tail bit attachment

Radio frame segmentation

1971+NRM4

7872

Extracted from 3GPP 25.944




UL TrCH multiplexingof 64 kbps and 3,4 kbpsdata

#1#1 #2 #3 #4

UL 64 kbps data UL 3,4 kbps data

#2 #3 #4

#1 #1 #2 #2 #3 #3 #4 #4

2nd interleaving

Physical channel mapping

TrCH multiplexing




>> On which physical channel are the UL 64 kbps data and the UL>> On which physical channel are the UL 64 kbps data and the UL3,4 kbps data? what is the spreading factor mapped? what is the3,4 kbps data? what is the spreading factor mapped? what is theDPDCH bit rate?DPDCH bit rate?

>> What is carried on DPCCH ?>> What is carried on DPCCH ?

?? kbps DPDCH

ys ca c a e app g

CFN=4N CFN=4N+1 CFN=4N+2 CFN=4N+3

15 kbps DPCCHCFN=4N CFN=4N+1 CFN=4N+2 CFN=4N+3



5 35 3 I P lI P t l

5. UTRAN

no

yes









5.85.8 Mobility ManagementMobility Management

5. UTRAN/5.7 Radio Resource Management(RRM)

RRM purposes

RRM is a set of algorithms to manage radio resources:

• Maximise the amount of radio resources available

Power control algorithmsHandover algorithms

• Allocation of radio resources




Which type of transport channel, transport format should bechosen to meet QoS requirements?

• Admission Control

In which conditions can a new user be admitted?

• Load Control (congestion control)

What should be done to avoid congestion?

In RRM all layers are involved under RRC control.

5. UTRAN/5.7 Radio Resource Management (RRM)

RRM functions

w UE dedicated functions, implemented in SRNC and NodeB:t

Selection of radio bearer parameters according to RABrequirements

t Closed loop power control

t Handover control




t RRC states management according to UE traffic volume

t DL dynamic scheduling on DCHw UTRAN dedicated functions, implemented in CRNC:

t Radio admission control

t Code allocation

t Radio load control

t Open loop power control



5. UTRAN/5.7 Radio Resource Management(RRM)

Admission and Load Control

Both procedures are handled by CRNC. They are estimatedseparately for uplink and downlink directions.

Admission Control This algorithm is executed when a radio bearer is to be setup ormodified. It is based on:

•Power transmission criteria (noise increase in UL transmit




•Power transmission criteria (noise increase in UL, transmitcapacity in DL)

•Number of active users in the frequency band (codemanagement)

And performed according to:• The type of required QoS• The current system load

Load Control (Congestion Control) This algorithm ensures that the system is not overloaded andremains stable.In case of congestion some actions can be taken.But overload situations should normally be exceptional.

5.15.1 From Radio Bearers toFrom Radio Bearers to transporttransport channelschannels


5. UTRAN

Layer 3

Layer 2

Layer 1

UE RNCNode B










5. UTRAN/5.8 Mobility management

General description (1/2)

The mobility management enables a user to have access to thesubscribed services on the whole coverage of the usual network

and possibly visited networks. It is performed as long as the UEremains switched on. It needs a lot of radio and networkresources.

• UE in idle mode (network mobility)




UE in idle mode (network mobility)Wherever the UE is located in the network coverage:

- the UE should have an access point to the network in the uplink>> Cell reselection mechanisms- the network should be able to reach the UE in the downlink (paging)

>> Location Area (LA) / Routing Area (RA) update mechanisms

• UE in connected mode (radio mobility management)

A connection to the UTRAN (RRC connection) has been established:this connection should remain, when the UE moves from one cell to

another.

>> Handover (HO) or cell update mechanisms


General description (2/2)

• UE in idle mode This mode is entered after “justafter switch on” process.

The UE location is:

- known by the CN at LA or RAlevel

- not known by the UTRAN

UE UTRAN

Idle

“Just after switch on” process

Detache

d




not known by the UTRAN

Uu

mode

Connected mode

•UE in connected mode This mode is entered after RRC

connection establishment.

The UE location is:

- known by the CN at a LA or RA

level (furthermore the MSC or the

SGSN knows the SRNC of the UE)- known by the UTRAN at a cell or

URA level.

RRC connection establishment


UE in idle mode (1/2)

?

When moving across thenetwork, the UE may have to

perform a cell reselection, if theinitial cell on which it is campedis no longer available or is nolonger the best suited.




The cell reselection is performed autonomously by the UE, but thenetwork can influence it by changing the radio parameters used in

radio criteria.

These radio parameters are transmitted in the Broadcast Channel(BCH).

? The cell reselection consists of

a selection of candidate cellsand a ranking of these cellsaccording to radio criteria.




UE in connected mode (1/3)

MM mechanisms Effect during the call

hard HO very short cutCell_DCH soft HO no cuthard HO very short cutCell_FACHcell update suspended




Cell_PCH cell update suspended

URA_PCH URA update suspended

Cell update (URA update) consists of updating the MS locationinformation stored in the SRNC.

A UTRA originated paging message will therefore be sent only inthis cell (this URA) and not in a whole LA or RA.


UE in connected mode(2/3)

Soft HO•inter-cell (softer HO, managed by Node-B)

•inter Node-B

•inter-RNC (SRNS relocation)

Hard HO•intra CDMA carrier

cell 1 cell 2




•intra CDMA-carriernot recommended for dedicated channels,

but necessary for common channels for which soft HO is not applied•inter CDMA-carrier

one operator can have two CDMA carriers or morebetween two different operators

•inter-modeFDD-TDD (not provided in R99)

•inter-systemUMTS-GSM: necessary to provide continuous coverageUMTS-CDMA2000 (in the US?)

Cell reselection•Inter-system : UMTS/GPRS (inter/intra carrier, inter/intra RNC)


UE in connected mode(3/3)

A hard handover consists of forwarding a call on another channelwhich is running on a different carrier.

UTRAcell

GSMcell- Dual receiver

•simple handover operation, but expensive receiver

The terminal must make measurements onother frequencies (FFD, GSM or TDDfrequencies) whilst holding the on-goingconnection :




Downlink

10msframe

Idleperio

d

Compressed frame

p p , p

- Compressed mode (or slotted mode)

•simple receiver, but complicated handover operation•the information is compressed time periodically (a few ms), inorder to perform measurements on the other frequencieswithout losing data



Appendix




• “Just after switch on” process• AMR codec

•NBAP elementary procedures

•RANAP elementary procedures



Appendix/AMR codec

AMR codec (for CS domain)

AMR mode Source coding bit-rateClass

AClass

BClass

C

AMR_12.20 12.20 kbit/s (GSM EFR) 81 103 60

AMR_10.20 10.20 kbit/s 65 99 40

AMR_7.95 7.95 kbit/s 75 84 0

AMR_7.40 7.40 kbit/s (IS-641) 61 87 0

AMR_6.70 6.70 kbit/s (PDC-EFR) 58 76 0

AMR_5.90 5.90 kbit/s 55 63 0

AMR_5.15 5.15 kbit/s 49 54 0

AMR_4.75 4.75 kbit/s 42 53 0




The AMR (Adaptative Multirate) speech codec:

- offers 8 AMR modes between 4,75 kbits/s and 12,2 kbits/s

- is capable of switching its bit rate every 20 ms upon command of the RNC

- is located in the UE and in the transcoder (which is located in theCN)

Appendix/NBAP elementary procedures

NBAP elementaryprocedures

•Cell Configuration Management. This function gives the CRNC the possibility to manage the cellconfiguration information in a Node B.

•Common Transport Channel Management. This function gives the CRNC the possibility tomanage the configuration of Common Transport Channels in a Node B.

•System Information Management. This function gives the CRNC the ability to manage thescheduling of System Information to be broadcast in a cell.

•Resource Event Management. This function gives the Node B the ability to inform the CRNCabout the status of Node B resources.

C fi ti Ali t Thi f ti i th CRNC d th N d B th ibilit t if

NBAP Functions (see 3GPP 25.433)




•Configuration Alignment. This function gives the CRNC and the Node B the possibility to verifythat both nodes has the same information on the configuration of the radio resources.

•Measurements on Common Resources. This function allows the CRNC to initiate measurementsin the Node B. The function also allows the Node B to report the result of the measurements.

•Radio Link Supervision. This function allows the CRNC to report failures and restorations of aRadio Link.

•Compressed Mode Control [FDD]. This function allows the CRNC to control the usage of compressed mode in a Node B.

•Measurements on Dedicated Resources. This function allows the CRNC to initiate measurements

in the NodeB. The function also allows the NodeB to report the result of the measurements.

•DL Power Drifting Correction (FDD). This function allows the CRNC to adjust the DL power level of one or more Radio Links in order to avoid DL power drifting between the Radio Links.



Appendix/RSNAP elementary procedures

RSNAP elementaryprocedures

•Radio Link Management. This function allows the SRNC to manage radio links using dedicatedresources in a DRNS;

•Physical Channel Reconfiguration. This function allows the DRNC to reallocate the physicalchannel resources for a Radio Link;

•Radio Link Supervision. This function allows the DRNC to report failures and restorations of aRadio Link;

•Compressed Mode Control [FDD]. This function allows the SRNC to control the usage of compressed mode within a DRNS;

RSNAP Functions (some of them (see 3GPP 25.423))




compressed mode within a DRNS;

•Measurements on Dedicated Resources. This function allows the SRNC to initiate measurementson dedicated resources in the DRNS. The function also allows the DRNC to report the result of themeasurements;

•DL Power Drifting Correction [FDD]. This function allows the SRNC to adjust the DL power levelof one or more Radio Links in order to avoid DL power drifting between the Radio Links;

•CCCH Signalling Transfer. This function allows the SRNC and DRNC to pass information betweenthe UE and the SRNC on a CCCH controlled by the DRNS;

•Paging. This function allows the SRNC to page a UE in a URA or a cell in the DRNS;

•Common Transport Channel Resources Management. This function allows the SRNC to utiliseCommon Transport Channel Resources within the DRNS (excluding DSCH resources for FDD);

•Relocation Execution. This function allows the SRNC to finalise a Relocation previously preparedvia other interfaces.



Abbreviations and

Acronyms (1)

AAL ATM Adaptation Layer

ACELP Algebraic Code Excited Linear Prediction

ADN Abbreviated Dialling Number

ALCAP Access Link Control Application PartAMR Adaptive Multi Rate

ATM Asynchronous Transfer Mode

BCCH Broadcast Control Channel

BCH Broadcast Channel

BHCA Busy Hour Call Attempts

CCCH Common Control Channel CCTrCH Coded Composite Transport Channel

CDMA Code Division Multiple Access

CDR Call Detail RecordCN Core Network

CPCH Common Packet Channel

CRNC Controlling RNC

CS Circuit Switched

CTCH Common Traffic Channel




BER Bit Error Rate

BLER Block Error RateBMC Broadcast / Multicast Control

BM-IWF Broadcast Multicast InterWorking

Function

BSC Base Station Controller

BSS Base Station (sub)System

BTS Base Transceiver Station

CAMEL Customized Application for MobileEnhanced Logic

CC Call Control

DCA Dynamic channel Allocation

DCCH Dedicated Control ChannelDCH Dedicated Channel

DHO Diversity HandOver

DHT Diversity HandOver Trunk

DRAC Dynamic Resource Allocation Control

DRNC Drift RNC

DS Direct Sequence

DSCH Downlink Shared ChannelDTCH Dedicated Traffic Channel

Abbreviations and

Acronyms (2)

EDGE Enhanced Data rates for GSM Evolution

ERAN EDGE Radio Access Network (all-IP)

FACH Forward Access Channel

FBI FeedBack InformationFDD Frequency Division Duplex

FDD-DS FDD-Direct Sequence (FDD1)

FDD-MC FDD-Multiple Carrier (FDD2)

FER Frame Error Rate

FP Frame Protocol

IETF Internet Engineering Task Force

IMEI International Mobile Equipment Identity

IMSI International Mobile Subscriber Identity

IP Internet ProtocolIR Incremental Redundancy

ISDN Integrated Services Digital Network

L1,L2,L3 Layer 1, Layer 2, Layer 3

LA Location Area

LCS Location Services




FTP File Transfer Protocol

GERAN GSM/EDGE Radio Access NetworkGGSN Gateway GPRS Support Node

GPRS General Packet Radio Service

GSM Global System for Mobile Communications

GSN GPRS Support Node (ie SGSN or GGSN)

GTP GPRS Tunneling Protocol

GTP-U GPRS Tunneling Protocol-User Plane

HO HandOverHPLMN Home PLM

LLC Logical Link Control

LQC Link Quality ControlM3UA SS7 MTP3 User Adaptation layer

MAC Medium Access Control

MBS Multi-standard Base Station

MC Multiple Carrier

MExE Mobile Execution Environment

MM Mobility Management

MSC Mobile-services Switching CenterMSP Multiple Subscriber Profile

Abbreviations and

Acronyms (3)

MTP3 Message Transfer Part (broadband)

MTP-3B Message Transfer Part level 3

NAS Non Access Stratum

NBAP Node-B Application PartODMA Opportunity Driven Multiple Access

OSA Open service Architecture

OTDOA-IPDL Observed Time Difference of ArrivalIdle Period Downlink

OVSF Orthogonal Variable Spreading Factor

PCCH Paging Control Channel

PS Packet Switched

QOS Quality Of Service

QPSK Quadrature Phase Shift Keying

RA Routing AreaRAB Radio Access Bearer

RACH Random Access Channel

RAN Radio Access Network

RANAP RAN Application Part

RB Radio Bearer




PCCH Paging Control Channel

PCH Paging ChannelPDA Personal Digital Assistant

PDC Personal Digital Cellular (2G Japan)

PDP Packet Data Protocol

PDU Protocol Data Unit

PLMN Public Land Mobile Network

PRACH Physical Random Access Channel

RL Radio Link

RLC Radio Link ControlRNC Radio Network Controller

RNS Radio Network Sub-System

RNSAP RNS Application Part

RNTI Radio Network Temporary Identity

RRC Radio Resource Control

RRM Radio Resource Management

Abbreviations and

Acronyms (4)

SAP Service Access Point

SAT SIM Application Toolkit

SDU Service Data Unit

SF Spreading FactorSGSN Serving GPRS Support Node

SHO Soft HandOver

SIR Signal to Interference Ratio

SMS Short Message Service

SPU Signaling Processing Unit

TF Transport Format

TFC Transport Format Combination

TFCI Transport Format Combination Indicator

TFCS Transport Format Combination Set TFS Transport Format Set

TMSI Temporary Mobile Station Identity

TPC Transmission Power Control

UDP User Datagram Protocol

UICC UMTS Integrated Circuit Card




SRNC Serving RNC

SSCOP Service Specific Connection OrientedProtocol

SSCP Signaling Connection Control Part

STM Synchronous Transfer Mode

TC Transcoder

TCP Transport Control Protocol

TD-CDMATime Division & CDMA

TDD Time Division Duplex TDMA Time Division Multiple Access

UMTS Universal Mobile Telecommunication

SystemUSIM UMTS Subscriber Identity Card

USSD Unstructured Supplementary ServiceData

URA UTRAN Registration Area

URAN UMTS Radio Access Network (ETSI)

Universal Radio Access Network (3GPP)

USB Universal Serial BusUTRAN UMTS Terrestrial Radio Access Network

Abbreviations and

Acronyms (5)

VC Virtual Channel

VHE Virtual Home Environment

VoIP Voice over IP

VP Virtual PathWAP Wireless Application Protocol

W-CDMA Wideband Code Division MultipleAccess

WIM WAP Identity Module

52255391 utran description 3 days

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