umts introduction 1

© Alcatel University –10445ACAAWBZZA Ed.1

UMTS/UTRAN Introduction

Training Manuel3FL10445ACAAWBZZA Ed.1

September 2005


Contents

1 Introduction1.1 Context1.2 Standardization1.3 UMTS Goals1.4 UMTS Technical Overview

2 Services Provided2.1 UMTS Services Principles2.1 UMTS Bearer Services2.3 Tele-Services2.4 UMTS Terminals

3 UTRAN System Description3.1 Logical Architecture3.2 Network Protocols3.3 Radio Channels3.4 Radio Protocols

4 WCDMA for UMTS4.1 Context4.2 Analogy4.3 Spread spectrum modulation4.4 Code Division Multiple Access (CDMA)4.5 Soft handover4.6 Rake receiver4.7 Power control4.8 Capacity, Coverage & Quality

5 UTRAN Scenario5.1 Radio Channels Mapping5.2 Service Request5.3 RAB Establishment5.4 Mobility Management in Connected Mode


Objectives

Instructional objectives Yes (or

Globally yes)

No (or globally

no) Comments

1 Describe mobile system standards evolution

2 Describe UMTS services , new capacity figures and service architecture

3 Draw the UTRAN architecture with the protocol stack (radio & network) of each Network Element and to define the channels used by these protocols

4 Define a Radio Resource in 3G.

5 Build the map of the channels (logical, transport, physical) from a white paper

Contract number :

Course title :

Client (Company, centre) :

Language : dates from : to :

Number of trainees : Location :

Surname, First name :

Did you meet the following objectives ?Tick the corresponding box

Please, return this sheet to the trainer at the end of the training


1. INTRODUCTION


UMTS/UTRAN Introduction 3FL10445ACAAWBZZA Ed.1 Page 5

Introduction Content> Objective: to be able to describe mobile system standards

evolution

> Program:

• Context• Standardization• UMTS Goals• UMTS Technical Overview


1. INTRODUCTION

1.1 Context



CONTEXTDefinition

Universal

Mobile

Telecommunication

System

“UMTS is one of the major new third generation mobile communications systems being developed within the framework which has been defined by the ITU and known as IMT-2000”

UMTS Forum

Will explain “3rd generation”-->1.1 HistoricalWill explain “IMT-2000 defined by ITU”-->1.2 Standardization

The UMTS Forum is an international and independent body, uniquely committed through the building of cross-industry consensus to the successful introduction and development of UMTS/IMT-2000 ’’third generation’’ mobile communications systemswww.umts-forum.org



CONTEXTPast mobile systems (1)

First Generation (1G)

In the early 80’s, analog systemse.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



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 rate

Limitations of 2G:• Congestionmore than 300 million wireless subscribers worldwide -->need to increase system capacity

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

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

CONTEXTPast mobile systems (2)

• Congestionmore than 300 million wireless subscribers worldwide -->booming market -->congestion of 2G (Japan case )-->need to increase system capacity

• Limited mobility around the worldgreat amount of 2G systems not compatible with each other-->need for a global standardisation

• Limited offer of servicesmore than 200 million internet users ⇒ communications are not limited to speech anymore ⇒ 2G are too limited to offer data services (low bit rate, circuit switching) ⇒ Need for new multimedia services and applications (video telephony, e-commerce...)



CONTEXTTechnical solutions

Two types of solutions were possible :

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



CONTEXTGSM evolution (1)HSCSD (High Speed Circuit Switched Data)Principle: to enhance channel coding scheme and to bundle GSM time slots on a circuit-switched basis.

Performance: up to 115,2 kbps

Already implemented but not all operators/manufacturers have made this choice.

GPRS (General Packet Radio Service)

Principle: to enhance channel coding scheme and to bundle GSM time slots on a packet-switched basis (the allocation of time slots is performed dynamically at the initialisation and during the connection)

Performance: up to 171,2 kbps

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

Note: Alcatel will skip HSCSD!



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 areas or for operators who do not have 3G licences, although the 3G brings more in terms of new multimedia services.

CONTEXTGSM evolution (2)

EDGE mainly concerns the modulation scheme on the GSM timeslots. The modulation technique that GSM uses is called Gaussian Minimum Shift Keying (GMSK). With GMSK, one bit per symbol can be transmitted (21=2 phase states). EDGE will extend these boundaries by applying a new alternative modulation technique, that is 8 Phase Shift Keying. 8PSK provides for the transmission of 3 bits per symbol (23 phase states) , that is three times the transmission rate of GMSK.

Krunal

Gaussian Minimum Shift Keying (GMSK).



CONTEXTLet’s take some examples!

> A 2 1/2 minutes MP3 music file (2.4 MBytes)

GSM 34 mnGPRS 7 mnEDGE 128 s UMTS 10 s

> Audio and Video streaming

Streaming with alltechnologies

except with GSM

> Downloading a map (50 KBytes)

GSM 42 sGPRS 8 sEDGE 3 sUMTS 0.2 s

> Downloading a Word document(500 KBytes)

GSM 7 mnGPRS 82 sEDGE 27 sUMTS 2 s

In these examples, the useful rate is supposed to be :9.6 Kbps for GSM50 Kbps for GPRS150 Kbps for EDGE2 Mbps for UMTS

same examples with different rates for GPRS :Downloading a Map: 13 s with GPRS CS-2 and 3 Time Slots (~30Kbps)Downloading a Word Document: 135 s with GPRS CS-2 and 3 Time Slots


1. INTRODUCTION

1.2 Standardization



STANDARDIZATION IMT-2000: definition

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

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

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

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 fixed networks

*A recommendation is not a specification.

IMT-2000: International Mobile Telecommunications-2000ITU:International Telecommunication Union (www.itu.int)

Problem: 2GHz is already used by 2G systems in US : shall the frequency carriers of 2G be reframed? Isn’t EDGE the most suitable technology for 3G systems?



STANDARDIZATIONIMT-2000: main participants

Europe: ETSI

Japan: ARIB

USA: TIA, T1

South Korea: TTA

China: CWTS

ITU: International Telecommunication Union

ITU is an international organisation composed of members of governments all over the world.

ETSI, ARIB, TIA… are regional standardization bodies composed of companies such as manufacturers and operators.

IMT-2000 is a result of the collaboration between the ITU and several regional standardization bodies, which are located mainly in Europe, in Japan and in the US

In the first phase of 3rd generation standardization, each region carried out its own standardization process to meet the IMT-2000 requirements but also to take into account its own 2nd generation mobile systems.

As similar technologies were being standardized in several regions around the world, initiatives were made to create a single forum for WCDMA standardization for a common WCDMA specification, e.g 3GPP (Third Generation Project Partnership), 3GPP2

Each Consortium has proposed one or more Radio Interfaces for IMT-2000, which have been approved for ITU. UMTS contains the two interfaces standardized by 3GPP: IMT-DS and IMT-TC.



STANDARDIZATIONIMT-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/Network Connection

Evolved IS-41 Core Network

Evolved GSM Core Network

Which radio technologies belong to UMTS?

UMTS contains the two interfaces standardized by 3GPP: IMT-DS also called UMTS FDD and IMT-TC also called UMTS TDD. UMTS core network is the evolved GSM network.

Different regions of the world will adopt different radio interface technologies according to the existing 2G system.

The connection of these different radio technologies to different core networks will require cooperation between the current standardization bodies. UMTS Release 99 does not contain these options.

ERAN: EDGE Radio Access Network



STANDARDIZATION2G Terrestrial Radio Interfaces

1999 Market Share: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 :

Note: CDMA in yellow is cdmaOne (IS-95)

Market share between digital systemsGSM = 48%CDMA = 28% TDMA = 15% PDC = 9%

Western Europe: GSM = 100%US & Canada: GSM = 12% CDMA = 49% TDMA = 39%China: GSM = 87% CDMA = 13%Japan: CDMA = 36% PDC = 64%RoW: GSM = 41% CDMA = 35% TDMA= 24%

For information: 1999 total market (including analog systems): 41.8 B$(US & Canada = 8.9 B$ Western Europe = 8.8 B$ China = 4.8 B$ Japan = 4.6 B$)



1999 Market Share:GSM 48 %CDMA 28 %TDMA 15 %PDC 9 %

UMTSCDMA2000EDGE

IMT2000

STANDARDIZATION3G 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%)

CDMA2000

UMTS

UMTS

UMTS

UMTS

EDGE

EDGE

CDMA2000

CDMA2000

UMTS

UMTS

CDMA2000

EDGE

China :

What about Global Roaming?

ITU leads this process of harmonizing, which is necessary for a global terminal roaming and to offer operators some degree of flexibility in selecting their 3rd generation technology.

However because of different radio technologies global roaming will continue to require specific arrangements between operators, such as multi-mode and multi-band handsets and roaming gateways between the different core networks.

We can also imagine a compatibility of SIM cards instead of multi-mode handsets (ieusing a UMTS SIM card in a CDMA2000 terminal)

In fact, Global Roaming is not the issue :

The challenge is roaming and seamless services across boarders of heterogeneous private and public, fixed and mobile access networks rather than Global Roaming.



STANDARDIZATION3GPP: Joint Organization for 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 Network

WCDMA (UTRA FDD)TD-CDMA (UTRA TDD)

Core Network Evolved GSM All-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.

3GPP is a joint organization of standardization bodies of Europe, Japan and US

To meet new market requirements, 3GPP specifications are continually being enhanced with new features. In order to provide developers with a stable platform for implementation while at the same time allowing the addition of new features, the 3GPP uses a system of parallel "releases”: release 99, release 4, release 5, ...

R99, The first Release of the 3rd generation specifications was essentially a consolidation of the underlying GSM specifications and the development of the new radio access network. The foundations were laid for future high-speed traffic transfer in both circuit switched and packet switched modes.

R99 is based on ATM transmission technology architecture through the RAN towards CN



STANDARDIZATION 3GPP: TSG Organization

CN WG1Mobility Management,

Call Control,Session Management

CN WG2CAMEL

CN WG3Interworking with

External Networks

TSG CNCore Network

RAN WG1Radio layer 1specification

RAN WG2Radio Layer 2 &Radio Layer 3 RR

specification

RAN WG3Iub, Iur, Iu specification &

UTRAN O&M requirements

RAN WG4Radio performance &

Protocol aspects

TSG RANRadio Access Networks

SA WG1Services

SA WG2Architecture

SA WG3Security

SA WG4CODEC

SA WG5Telecom Management

TSG SAService and System

Aspects

T WG1Mobile Terminal

Conformance Testing

T WG2Mobile terminal

services & capabilities

T WG3Smart Card

Application aspects

TSG T Terminals

CN WG4MAP/GTP /BCH/SS

CN WG5OSA

Open Service Access

TSG GERAN GSM EDGE

Radio Access Network

GERAN WG1Radio Aspects

GERAN WG2Protocol Aspects

GERAN WG3Terminal Testing

Project Co-ordination Group(PCG)

3GPP is large organization, which was created in 1998.Detailed technical work is carried out in 5 Technical Specification Groups (TSG) divided into subgroups. Many people are involved: it is estimated that more than one thousand people contribute in one way or another. This is an unprecedented number of experts working on the same project.3GPP has delivered almost stable specifications, accepted by the majority of major industrial players, in only two years.



STANDARDIZATION 3GPP specifications

Series_Id Series_description21. Requirements22. Service Aspects23. Technical Realization24. Signaling Protocols (UE to network)25. UTRA aspects26. CODECs27. Data28. (reserved)29. Signaling Protocols (intra-fixed network)30. Program management31. User Identity Module32. O&M33. Security Aspects34. Test specification35. Security algorithms

http://www.3gpp.org/specs/specs.htm

For informationNB : the TS 21.101 lists the existing Technical Specifications for the release R 99.NB : the TS 21.102 lists the existing Technical Specifications for the release R 4.NB : the TS 21.103 lists the existing Technical Specifications for the release R 5.



STANDARDIZATIONUMTS Roadmap

EDGEEDGECommercialCommercialintroduction introduction

UMTS R5UMTS R5

UMTS R99UMTS R99Field TrialsField Trials

2001 20032002

GPRSGPRSimplementationimplementation

UMTS R99UMTS R99commercialcommercial

SystemSystem

2004

GPRS implementation:TMN: November 2000: 1st European operatorTelering: January 2001

UMTS:field trials starting from end 2001

EDGEHSDS (High Speed Data Service) is available with Evolium™ BSS in B8 release for E-GPRS


1. INTRODUCTION

1.3 UMTS Goals



UMTS GoalsWhy UMTS?

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

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

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

UMTS Forum 1997

High quality Voice (enhancement compared to GSM)Data (multimedia)

Convergence Fixed and mobile networksData and telecommunication networks (mobile phone and computer may merge)

ServicesNew, personalized, ubiquitous (but yet to be invented!)Depend on the location

•countryside and big cities •high bit rate services will be offered when standing close to the base station

Depend on the terminal•different classes of terminals according to the services the user will have



UMTS GoalsUMTS vision

Satellite

Macro-Cell Micro-Cell

Zone 2: UrbanZone 1: In-Building

Pico-Cell

Zone 4: Global

Zone 3: Suburban

UTRA/ TDDUTRA/ FDDMSS GSM

To access services from everywhere in the world,but radio interfaces should be adapted to the environment2 Mbps ⇒small cells (due to interference level)144 kbps ⇒large cells

Transmission in TDD is discontinuous. This implies a reduced average transmission power and leads to smaller cells for TDD (pico and micro).

What about UMTS deployment?UMTS will be compatible with GSM networks (Handover between the two systems should be applied)There will be UMTS islands in a sea of GSM (at least at the beginning)

What about the satellite component?The MSS (Mobile Satellite Service) is also called Satellite Component.It aims to fill the gap coverage, especially maritime coverage, and to provide global roaming (niche market of global roamers)But it cannot penetrate the core of modern buildings.It is likely to come by 2007.


1. INTRODUCTION

1.4 UMTS Technical Overview



UMTS Technical OverviewUMTS general architecture

Core network (CN)it provides support for the network features and telecommunication services. It is connected to external CS networks or PS networks.

Radio Access network (RAN)it comprises roughly the functions specific to the access technique.3 different RANs are foreseen:•UTRAN (UMTS Terrestrial RAN)•MSS (Mobile Satellite component)•BRAN (Broadband RAN)

User Equipment (UE)It is the mobile phone.

Iu

RAN

UEUu

CN Core NetworkRAN Radio Access NetworkUE User Equipment

CN

CS networks (PSTN, ISDN..)

PS networks(Internet…)

It is the same well-known architecture as the 2nd generation mobile system, but ⇒ Reconfiguration of the AN, or changes in the AN domain functionality shall have minimal impact on Core Network functions, and vice-versa.

⇒ A given Access Network (e.g., the UTRAN) may provide access to different type of Core Networks via the Iu reference point and vice versa (UTRAN, BRAN, Satellite)

That’s why we speak about Iu reference point, not about Iu interface (an interface differs from a reference point in that an interface is defined where specific information is exchanged and needs to be fully recognised)

In the following material we will not speak about MSS and BRAN, only about UTRAN.



UMTS Technical OverviewUMTS Cellular System

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

GSMUsers are separated in frequency

(FDMA) and in time (TDMA)

UMTSUsers are separated with codes

(CDMA)



UMTS Technical OverviewUMTS duplex modes

Downlink

UplinkFDD modeCode and Frequency

orthogonality

f1

f2

5 MHz channel

15TS

5 MHz channel

TDD modeCode and Time

orthogonality

Uplink & Downlink ......

• FDD (Frequency Division Duplex): use of DS-CDMA (or W-CDMA)Frequency Bands 1920/1980 MHz (UL) / 2110/2170 MHz (DL): Region 1Channel Spacing 5 MHzChannel Raster 200 kHzCarrier chip rate 3.84 Mchip/sRadio Frame length 10 ms with 15 TSFEC codes Convolutional codes, Turbo-codesModulation QPSKBearer Capability up to 2 MbpsInter RNS synchro not needed

• TDD (Time Division Duplex): use of TD-CDMAFrequency Band 1900/1920 MHz and 2010/2025 MHz (UL&DL)Idem FDDInter RNS synchro needed

The variable rates are achieved by the used of codes (& multi-slot allocation for the specific case of TDD)FDD (Frequency Division Duplex) shall provides a continuous 3G coverage.TDD (Time Division Duplex) mode provides specific solutions for asymmetric trafficand dedicated indoor systems, in line with the market requirementsIn the following material we will focus on UMTS FDD

Note : FEC = Forward Error Correction

Krunal

• FDD (Frequency Division Duplex): use of DS-CDMA (or W-CDMA) Frequency Bands 1920/1980 MHz (UL) / 2110/2170 MHz (DL): Region 1 Channel Spacing 5 MHz Channel Raster 200 kHz Carrier chip rate 3.84 Mchip/s Radio Frame length 10 ms with 15 TS FEC codes Convolutional codes, Turbo-codes Modulation QPSK Bearer Capability up to 2 Mbps Inter RNS synchro not needed



UMTS Technical OverviewUMTS Frequency allocations

TDD FDD MSS TDD1900 1980 2010 20251920

MSSFDD2110 2170 2200

FDD: Frequency Division DuplexTDD: Time Division DuplexMSS: Mobile Satellite System

Uplink Downlink

The FDD band is split into 6 licenses in Germany, into 4 in France.

MSS not allocated yet.

No band guards between operators and between TDD and FDD: it may cause problems!⇒Need for cooperation between operators



INTRODUCTIONQUIZ! (1)

Mark the following answers to the questions A to E by True or False.

A. What are the limits of 2G systems like GSM?

1/ No security of communications

2/ No dynamical allocation of radio resources

3/ Mobility only in a small area

4/ Heavy mobile phones

5/ Limited offer of data services

B. EDGE...

1/ is an evolution of GSM

2/ is sometimes considered as a 3G system

3/ is based on a new modulation scheme

4/ is supposed to reach a bit rate about 40 times greater than the GSM one

Krunal

5/ Limited offer of data services

Krunal

1/ is an evolution of GSM



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

INTRODUCTIONQUIZ! (2)

Krunal

5 MHz

Krunal

1/ 3GPP


2. Service Provided



Services Provided Content> Objective: to be able to describe UMTS services , new capacity

figures and service architecture

> Program:

•• UMTS services principlesUMTS services principles•• UMTS Bearer servicesUMTS Bearer services•• TeleTele--servicesservices• UMTS Terminals


2. Service Provided

2.1 UMTS Services Principles



UMTS Service PrinciplesWhat is a service?

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

E.g data transfer at 9,6 kbps, intransparent mode, with turbocode...

UTRAN CN CNGateway

TE

UMTS Bearer Service External BearerService

UMTS Bearer Service

Radio Access Bearer Service(RAB)

CN BearerService

BackboneBearer Service

Iu BearerService

Radio BearerService

Radio Physical Bearer Service

PhysicalBearer Service

Uu Iu

Teleservice

... ...

TE/MT Node

Basic telecommunication services are divided in two broad categories:

- bearer services: provide the capability of transmission of signals between access points. They are related to lower layers.

- tele-services: provide the complete capability, including terminal equipment functions, for communication between users. They are related to higher layers.

Examples:

- Bearer services: transmission at 9,6 kbps with a max BER of 10-3. This service can not be used alone, it needs protocols of upper layers to be controlled and relayed.

-Tele-services: file transfer (the bit rate transfer depends not only on the bearer service but also on the application)

See 3GPP23.107



UMTS Services PrinciplesTele-services and Bearer services

TeleservicesSpeech, emergency calls

SMSEmailInternet Access

Mobile e-commerceVideo PostcardsInformation and location based services

New applications

UMTS Bearer servicesLarge toolkit for all kinds of services

“Instinctive” service

Basic services

Enhanced services

New services to be provided by service providers (third party)

Whereas 2G mobile systems offer mainly speech services (the content is provided by the user), UMTS has to support a wide range of applications with different quality of services.

New Services: we can also imagine that the customer himself will be able to create its own new services (easy access ways to create services)

UMTS bearer services shall provide the necessary capabilities to support multimedia services and to enable the user of a single terminal to establish and maintain several connections simultaneously.

3GPP shall standardise service capabilities (bearer services) and not the services (teleservices) themselves.

© Alcatel University –10445ACAAWBZZA Ed.1 Page 40


UMTS Services PrinciplesVirtual Home Environment (VHE)

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

• it enables end users to bring with them their Personal Service 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 interface preferences, …)

• The VHE is defined as a system concept for personalized service portability across network boundaries and between terminals.

• The exact configuration available to the user at any instant will be dependent upon the capabilities of the USIM, terminal equipment and network currently being used, on behalf of subscription restrictions.

• The VHE can be considered as a distributed user profile, owned by the service provider, distributed at any moment between the terminal equipment, the USIM, the network operator and the service provider.

• A user can reasonably expect the service to be the same in any network (home and visited). In fact this is not likely to be the case:- emergency numbers change from one country to another- announcements are preferably made in the local language- value-added services, such as traffic news, are not localized, but refer back to the home area

• The VHE is the framework for configuring the state of the terminal and the services accessible to it.

• The Personal Service Environment describes how the user wishes to manage and interact with its communications services. The PSE is a combination of a list of subscriptions (detailing provisioned services), preferences associated with those services, terminal interface preferences and other information related to the user's experience of the system. Within the PSE the user can manage multiple subscriptions e.g. both business and personal, multiple terminal types and express location and temporal preferences. The Personal Service Environment is defined in terms of one or more User Profiles.

See 3GPP 22.121



UMTS Services PrinciplesService Architecture

VHE concept is based on the standard mechanisms of Service Capability Servers which allow Service Capability Features. The latter are carried through standard interfaces in order to support Tele-services adapted to the Service Capabilities of the network and 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

VHE defines Service Capability Servers and standardises the features.Services capabilities:•Service capabilities are based on functionality and mechanisms /toolkits such as provided by SAT, MExE, IN and CAMEL. These service capabilities can be made visible to the applications through an application interface.Service Capability Servers:•GSM/GPRS/UMTS bearer services: they offer mechanisms for applications to access basic bearer capabilities. •MExE (Mobile Execution Environment) servers: Value added services are offered through a client/server relationship between the MExE server in the network and the Mobile Execution Environment (e.g. Java Virtual Machine or WAP browser) in the terminal (TS 22.057)•SAT (SIM Application Toolkit) servers: mechanisms that offer additional capabilities to the communication protocol between smart card and mobile station (TS 22.004)• CAMEL (Customised Application for Mobile networks Enhanced Logic) servers: CAMEL extends the scope of IN services provisioned to the mobile environment (TS 23.078)Service Capability Features•Functionality offered by service capabilities that are accessible via the standardised application interface. Examples: Call Control, Location/Positioning, PLMN Information & Notifications

Bearer Services:The service characteristics as they apply at a given reference point where the user accesses the bearer service.



UMTS Services PrinciplesLet’s Look for the nearest restaurant

Choose your preferences:

- type of restaurant: French

- type of payment: credit card

...

This service is built from the following service capability features: 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 with MExEBilling of the service : CAMEL

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

Other examples of (tele)services built from service capabilities features:

Call Barring : to prevent outgoing calls to certain sets of destinations, based on the number dialled and on a wider range of parameters (time of day, day of week, location, roaming, type of call requested, cost of the service and/or destination).

Call Filtering/Forwarding: this service allows the control of whether incoming calls are accepted, forwarded or terminated

Hold: this service allows an established call to be maintained, whilst suspending use of the bearer from the incoming access point of the network. This saves on both air interface and network traffic resources when a call is temporarily suspended.

Transfer: this service allows either an established or held call to be redirected to another destination.

Call-back When Free: this service allows to be informed when the destination is next able to accept the call, allowing a new call to be originated.

See 3GPP 22.105 (Annex A)


2. Service Provided

2.2 UMTS Bearer Services



UMTS BEARER SERVICESBearer Services Characterization

Bearer services are characterized by a set of end-to-end characteristics with requirements on QoS, always considered point-to-point.Bearer services provide the capability for information transfer between 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, non guaranteed/variable…), traffic characteristics (uni-directional, bi-directional, multicast…), priority• quality characteristics: maximum transfer delay, delay variation, bit error ratio, data rate.

This set of requirements are called QoS parameters. Example : several active radio bearer services can be handled simultaneously by the same terminal equipment.

See 3GPP TS 22.105

QoS: Quality of Service

PS and CS domains provide a specific set of bearer capabilities.



UMTS BEARER SERVICESBearer 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 or connection establishment (during an on going session or connection).

• support of asymmetric nature between uplink and downlink

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



UMTS BEARER SERVICESBearer Supported Bit Rates

The only limiting factor for satisfying application requirements shall be the cumulative bit rate per mobile termination at a given instant in each radio environment:

•At least 144 kbps in rural outdoor radio environment (with a maximum speed of 500 km/h)•At least 384 kbps in urban or suburban outdoor radio environments (with a maximum speed of 120 km/h)

•At least 2048 kbps in indoor or low range outdoor radio environment (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

The bit rate target have been specified according to the Integrated Services Digital Network (ISDN):- the 144 Kbps data rate provides the ISDN 2B+D channel- the 384 Kbps provides the ISDN H0 Channel- the 1920 Kbps provides the ISDN H12 Channel(even though 2Mbps is generally used as the upper limit for IMT-2000 services, the exact service is specified to be 1.92 or 2.048 Mbps)

Several backward compatibility requirements influence the technology applied to 3G systems.

See 3GPP TS 22.105


2. Service Provided

2.3 Tele-services



TELESERVICESTypology

Location services• 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

Transportation• Flight/train Schedule• reservation

Vertical application

• Traffic Management• Automation• Mobile branches • Health

Music• Downloading of

music files orvideo 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

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

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

Teleservices provide the full capabilities for communications by means of terminal equipment, network functions and possibly functions provided by dedicated centres.Multimedia teleservices support the transfer of several types of information.M-commerce :

•Non-physical = electronic goods (e-banking, e-flight ticketing, ...)•Physical = electronic payment of physical goods (food, supplies, hardware, ...)



TELESERVICESQoS classes

> 4 classes have been identified:• conversational

– AMR speech service – Video telephony

– CS: H324– PS: H323

• streaming• interactive

– Web-browsing– location based services

• background– e-mail delivery– SMS ...

Delay sensitive

+

-

Data Integritysensitive

-

+

•Conversational (real time user to user)•Adaptive Multi-Rate (AMR) speech service (see “Appendix” for more details):a multi-rate speech coder is used with 8 source rates: 12.2 (GSM-EFR), 10.2, 7.95, 7.40 (IS-41), 6.70 (PDC-EFR), 5.90, 5.15 and 4.75 Kbps.The AMR bit rates are controlled by the radio access network and do not depend on the voice activity. The AMR coder is able to switch its bit rate every 20ms.•Video telephony (H324, H323, IETF multimedia architecture)

•H324 (originally specified for PSTN) should be used for video in CS connections•H323 and IETF architecture (IETF SIP Session Initiation Protocol) are candidates for PS connections.

•Streaming (real time user to server)the data transfer has to be processed as a continuous stream. With streaming the browser can start displaying the data before the entire file has been transmitted These applications are typically unidirectional.

•Interactive (non real time user to server with delay requirements)•Web browsing•location based services•computer games (sometimes classified as conversational class due to end-to end delay)

•Background (non real time user to server with fewer delay requirements, from a few seconds to a few minutes):

•e-mail delivery •Short Message Service (SMS)

Real-time services have higher priority than non-real time services.See 3GPP 23.107



TELESERVICESPerformance

QoS of teleservices depends not only on UMTS network, but also on applications, terminals and external networks.From a user’s perspective it is more relevant to speak of delay rather than bit rate:

Errortolerant

Errorintolerant

Conversationaldelay <<1 sec

Interactivedelay<1 secStreaming

delay <10 secBackgrounddelay >10 sec

Conversationalvoice and video

Streaming audioand video Fax

E-mail arrivalnotification

E-commerce,WWW browsingTelnet,

interactive gamesFTP, still image,

paging

Voice messaging

Conversational speech

Audio transfer delay requirements depends on the level of interactivity of the end users. To preclude difficulties related to the dynamics of voice communications, ITU-T Recommendation G.114 recommends the following general limits for one-way transmission time (assuming echo control already taken care of):

0 to 150 ms preferred range

150 to 400 ms acceptable range (but with quality decreasing)

above 400 ms unacceptable range

Interactive games

Requirements for interactive games are obviously very dependent on the specific game, but it is clear that demanding applications will require very short delays, and a value of 250 ms is proposed, consistent with demanding interactive applications.

Web-browsing

In this category we will refer to retrieving and viewing the HTML component of a Web page, other components like images, audio/video clips are related to separate QoSClasses. From the user point of view, the main performance factor is how fast a page appears after it has been requested. A value of 2-4 seconds per page is proposed, however improvement on these figures to a target figure of 0.5 seconds would be desirable.

Delay values represent one -way delay (i.e. from originating entity to terminating entity).

See 3GPP TS 22.105 Annex B



TELESERVICESDefining Charging Principles

• How will billing be performed: by time? by volume? by number ofconnections?

• If billing is performed by volume, what will be an easy way to explain 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 might have higher priority or better QoS (depending of the operator’s strategies). Billing for a given service might depend on the QoS.

From 3GPP TS 22.115



TELESERVICESLocation based services

Teleservices will depend on the strategy and on the imagination of operators and content providers.

The key point is likely to be a fast access to information and an appropriate 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, consult yellow pages, get local traffic situation or weather report,...

Limitation: location information could be a risk for privacy.

At the moment UMTS specifies that it will provide location information to an accuracy of 50m. Different positioning methods are specified in R’99 such as:

•the cell coverage-based positioning method•Observed Time Difference Of Arrival-Idle Period Down-Link (OTDOA-IPDL)•network-assisted GPS methods

3GPP TS 22.071, TS 24.030



2.12.1 UMTS service principlesUMTS service principles

2.22.2 UMTS Bearer servicesUMTS Bearer services

2.32.3 TeleTele--servicesservices

2.42.4 UMTS Terminals UMTS Terminals

SERVICE PROVIDED


2. Service Provided

2.4 UMTS Terminals



UMTS Services Principles Third party: service provider

Tele-services will not be standardised so as to differentiate betweenoperators and providers of applications.UMTS offer new opportunity for content and service providers

Today’s 1:1 customer-operator relationship

Tomorrow’s situation?

OperatorContracted Content providers

Contracted Service providers

Contracted Service providers

Operator

Existing systems have largely standardised the complete sets of tele-services, applications and supplementary services which they provide. As a consequence, substantial re-engineering is often required to enable new services to be provided. In addition, the market for services is largely determined by operators and standardization. This makes it more difficult for operators to differentiate their services.

This is the reason why tele-services should not be standardized : to motivate competition between new actors of the telecommunication market, i.e content providers.

Today, it is hardly possible to predict the nature and the usage of most applications, as UMTS ought to be generic by nature to allow good support of existing applications and to ease the evolution of new applications.



UMTS TERMINALSUser Equipment (UE)

User Equipment (UE)

Cuinterface

Mobile Equipment

(ME)

UICCUSIM

USIM 2

1

GSMaccess

SIM

GSM/GPRS terminal

Functionally speaking, the User Equipment (UE) is composed of the Mobile Equipment (ME) and the UMTS Subscriber Identity Module (USIM).The Role of USIM is very similar to that of the SIM in GSM:- it is used to store subscriber identity, subscription data, authentication and ciphering keys, authentication algorithms - its security is improved compared to GSM with a mutual authentication between the card and the network.The interface between ME and USIM is the Cu interface, the importance of which is crucial for compatibility: even if full multi-mode Terminals will not be developed (in a first period at least), USIM-roaming will allow the subscriber to use different IMT2000 terminals with the same card.The UICC (UMTS integrated Circuit Card) is similar to SIM card in GSM with the same size (either ISO or plug-in).It may contain one or several USIM for different applications and also the SIM module in order to be used in a GSM terminal .Another possibility is to include additional mechanisms in the USIM part in order to provide the GSM access and be usable in a multi-mode UMTS/GSM terminal.

TS 21.111: USIM and IC card requirements



UMTS TERMINALSRange of Terminals

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

int

erfa

ces

Data / IT

E-Commerce

DomesticGPS

Integrated approach:1 handset able to perform all functions. Most of the concept phones today.

Distributed approach:1 handset for voice & WAP, or voice only and a Bluetooth connection to other devices (headset, camera...).

Bluetooth (See http://www.bluetooth.com) The idea was born in 1994. Ericsson initiated a study to investigate the feasibility of a low-power, low-cost radio interface between mobile phones and their accessories. The aim was to eliminate cables between mobile phones and PC cards, headsets and desk top devices… In February 1998, 5 companies (Ericsson, Nokia, IBM, Toshiba and Intel) ventured into a Special Interest Group (SIG)The Bluetooth system is operating in the 2.4 GHz ISM (Industrial Scientific Medicine) band. In a vast majority of countries around the world the range of this frequency band is 2400 - 2483.5 MHz. The equipment is classified into 3 power classes (class1 = 100mW=20dBm, class 2 = 2.5 mW=4dBm, class 3 = 1mW=0dBm

WAP (Wireless Application Protocol) WAP is a technology designed to provide users of mobile terminals with rapid and efficient access to the Internet.Today, most people access the Internet from a desktop or home PC, which has a large screen and comprehensive keyboard. The mobile phone, on the other hand, has limited display capabilities and a simple keyboard. WAP helps overcome these limitations. A special "micro browser" takes the information from the Web and pares it down so that only the key information required by the user is displayed.



SERVICES PROVIDEDQUIZ!

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 and fixed networks

3/ will be adapted to the terminal capabilities

4/ will use proprietary interfaces



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




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 initially scheduled because of non availability of UMTS terminals in volume: can you find some reasons which makes it quite complex to design UMTS terminals?



3. UMTS System Description



3. UMTS System Description Section presentation> Objective: to be able to draw the UTRAN architecture with the

protocol stack (radio and Iu) of each Network element and to define the channels generated by these protocols.

> Program: • 3.1 Logical Architecture• 3.2 Network Protocols• 3.3 UTRAN Channels• 3.4 UTRAN Radio Protocols



3.1 Logical Architecture



Logical ArchitectureUTRAN Situation & Core Network in 3GPP R4

Core Network

PSCN

Access Network

Iu-PS

External Networks

HLR

PSTN

IN network

UTRAN

RNCRNC

Node B

PDN

CS Links PS Links

GbBackbone AlcateAlcate

lliGGSNiGGSN

SGSNGSMBSS

BSC

BTS PCU

CSCNMSC Server

MGWGMSC

Iu-CS

A Public Land Mobile Network (PLMN) is composed of 2 main parts:

The Access Network (AN) provides the radio interface and radio resource management for mobile communications toward the Core Network (CN).

The Core network is in charge of User Equipment (UE) Mobility (MM) and Session (SM) management. It also deals with the external networks for voice call establishment or data session establishment.

The UMTS Terrestrial Radio Access Network (UTRAN) is the UMTS Access Network; it’s composed of Node Bs and Radio Network Controllers (RNCs).

An ATM switch interfaces the UTRAN and the CN:

• Iu-CS interface for the Circuit Switched Core Network (CSCN).

• Iu-PS interface for the Packet Switched Core Network (PSCN).

The PLMN connects specifically to the Public Switched Telephone Network (PSTN) for voice or to the Packet Data Network (PDN) for data.

The CN includes the Intelligent Network (IN) for value-added services.

Example of services:

For voice:

• Voice Call Prepaid Service

• SMS service

• Call Waiting

Krunal

The Core network is in charge of User Equipment (UE) Mobility (MM) and Session (SM) management. It also deals with the external networks for voice call establishment or data session establishment.

Krunal

The UMTS Terrestrial Radio Access Network (UTRAN) is the UMTS Access Network; it’s composed of Node Bs and Radio Network Controllers (RNCs).

Krunal

• Iu-CS interface for the Circuit Switched Core Network (CSCN). • Iu-PS interface for the Packet Switched Core Network (PSCN).



Logical Architecture UTRAN Logical Architecture

Core Network

UTRAN

UE

Iub Iub

Iu-CS Iu-PS

Iur

Uu Interface

RNS

CNCS CNPS

RNC RNC

Node B Node B

CN2 separated domains: Circuit Switched (CS) and Packet Switched (PS) which reuse the infrastructure of GSM and GPRS respectively.

UTRAN- new radio interface: CDMA- new transmission technology: ATM

CN independent of ANThe specificity of the access network due to mobile system should be transparent to the core network, which may potentially use any access technique. Radio specificity of the access network is hidden to the core network.UE radio mobility is fully controlled by UTRAN.

Some correspondences with GSM:CN NSS Uu UmUTRAN BSS Iub A-bisRNC BSC Iur no equivalentNode-B BTS Iu-CS AUE MS Iu-PS Gb



Logical Architecture Interfaces

Open Interfaces:

• The function of the Network Elements have been clearly specified by the 3GPP.•Their internal implementations issues are open for the manufacturer• All the interfaces have been defined in such a detailed level that the equipment at the endpoints can be from different manufacturers.

•“Open Interfaces” aim at motivating competition between manufacturers.

Physical implementation of Iu interfaces•Each Iu Interface may be implemented on any physical connection using any transport technology, mainly on E1 (cable), STM1 (Optic fiber) and micro-waves.•ATM will be provided in the 3GPP R4 release and IP is foreseen for the 3GPP R6

A manufacturer can produce only the Node-B (and not the RNC). This is not possible in GSM (A-bis is a proprietary interface)

The Iur physical connection can go through the CN using common physical links with Iu-CS and Iu-PS. However there is a direct logical connection between the 2 RNCs: the Iur information is not handled by the CN.



Logical ArchitectureNetwork Element Function

RNC: Radio Network ControllerIt is the intelligent part of the UTRAN:

-Radio resource management (code allocation, Power Control, congestion control, admission control)- Call management for the users- Connection to CS and PS Core Network- Radio mobility management

Iub IubIur

RNSNode B Node B

RNC RNC

An RNS (Radio Network Subsystem) contains one RNC (Radio Network Controller) and at least one Node-B.

The RNC takes a more important place in UTRAN than the BSC in the GSM BSS. Indeed RNC can perform soft HO, while in GSM there is no connection between BSCs and only hard HO can be applied.

Krunal

The RNC takes a more important place in UTRAN than the BSC in the GSM BSS. Indeed RNC can perform soft HO, while in GSM there is no connection between BSCs and only hard HO can be applied.



Logical ArchitectureNetwork Element Function

Node-BA Node-B can be considered, as first approximation, like a transcoder between the data received by antennas and the data in the ATM cell on the Iub.

- Radio transmission and reception handling- Involved in the mobility management- Involved in the power control

Iub

RNC

Node B

ATM Transport Technology

An RNS (Radio Network Subsystem) contains one RNC (Radio Network Controller) and at least one Node-B.

A Node-B is also more complex than the GSM BTS, because it handles softer HO.

Controlling RNC (CRNC): a role an RNC can take with respect to a specific set of Node-Bs (ie those Node-Bs belonging to the same RNS). There is only one CRNC for any Node-B. The CRNC has the overall control of the logical resources of its Node-Bs



3.2 Network Protocols



Network ProtocolsProtocols in UTRAN

Uu Interface

Core Network

RNC RNC

Node B

Iub

Iu

Iur

Iu Protocols

> The Iu protocols• Used to exchange data

(traffic and signaling) between RNCs, Node Bs and the Core Network.

Radio Protocols

> The Radio protocols• Used to process the

data sent on the air and for the signaling between UTRAN and the UEs

> NAS Signaling• Signaling between a

UE and the Core Network.

• Typically, the Authentification and the Location NAS Signaling

Iu Protocols : RANAP: Radio Access Network Application Protocol,RNSAP: Radio Network Sub-system Application Protocol,NBAP: Node B Application Protocol,ALCAP is a generic name for the signalling protocols of the Transport Network Control Plane used to establish/release Data Bearers.It makes establishment/release of Data Bearers on request of the Application Protocol.

Radio Protocols :RRC: Radio Resource ControlRLC: Radio Link ControlMAC: Medium Access Control

NAS refers to higher layers (3 to 7). Entities of this part will exchange tele-services

and bearer services.



Network ProtocolsProtocol Stack on the Interfaces

Iub

Iub

Iur

Iu- PS

Iu- CS

Node B

RNC

RNC

RNSAP

RANAP

RANAP

Iu UPVoice

Iur FP

Iu UPData

Control plane User plane

Iub

Node B

Node B

CS-CN

PS-CN

RadioSig Voice

NBAPIub FP

RadioSig Voice Data

AAL5 AAL2ATM

AAL5 AAL2ATM

AAL5 AAL2ATM

AAL5 AAL5ATM

Data

AAL5 has been designed to adapt non real time, connectionless oriented data at variablebit rate (eg, web browsing) to ATM.AAL2 has been designed to adapt real time, connection oriented data at variable bit rate(eg, voice in AMR) to ATM.



Network ProtocolsGeneral model

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

Application Protocols:

Radio

Network

Layer

Transport

Network

Layer

Physical Layer

SignalingBearer(s)

SignalingBearer(s)

DataBearer(s)

ALCAP

ApplicationProtocol

DataStream(s)

Transport Network Control Plane

Transport Network User Plane


Control Plane

User Plane

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

1. What is the 1. What is the purpose of the purpose of the separation between separation between the Radio Network the Radio Network Layer and the Layer and the Transport Network Transport Network Layer?Layer?

2. Why is ALCAP 2. Why is ALCAP protocol protocol necessary?necessary?

The Iu protocols are responsible for exchanges of signalling and user data between two endpoints of an Iu interface (e.g. Node-B and RNC over the Iub interface)



Network ProtocolsIub protocols

ATM

Radio

Network

Layer

Transport

Network

Layer

Physical Layer

AAL5 AAL2

ALCAP

NBAPFrame

Protocols(IubFP)

Control Plane User Plane

AAL5

RRC Connection Establishment*

Radio Link Establishment RABs*

NAS signalling*




Note: AAL2 and AAL5 are sub-layers of ATM which provide some adaptation between the application (voice, data, signalling) and the ATM layer.

NBAPis used to carry signalling (e.g Radio Link Establishment) Examples of actions of NBAP during Radio Link Establishment:- signalling exchanges over Iub, which permits the RNC to reserve radio resources of Node-B for the Radio Link- signalling transaction with ALCAP, which will setup a Iub data bearer (on AAL2) to carry the Radio Link

Frame ProtocolsAt this stage Data Streams (carrying RABs, NAS signalling, SMS Cell Broadcast service, RRC connection establishment…) have been mapped on transport channels The Frame Protocols (FP) define the structures of the frame and the basic in-band control procedures for every type of transport channels.

ALCAPis used to set up AAL2 connections for Data Streams.

BearersData Streams are carried on AAL2, which enables better bandwidth efficiency for user packets but requires its own signalling (ALCAP signalling is used to set up AAL2 connections for Data Streams).NBAP and ALCAP messages are carried on AAL5.



Network ProtocolsIur Protocols

ATM

Radio

Network

Layer

Transport

Network

Layer

Physical Layer

...

AAL5 AAL2

ALCAP

RNSAPFrame

Protocols (Iur FP)

Control Plane User Plane

AAL5

RRC Connection Establishment*

Establishment of an additional radio

link to an UE (for soft HO)

RABs*NAS signalling*




Note: AAL2 and AAL5 are sub-layers of ATM which provide some adaptation between the application (voice, data, signalling) and the ATM layer.

RNSAPIt is used to carry signalling (e.g Radio Link Establishment) e.g. actions of RNSAP during Radio Link Establishment:- signalling exchanges over Iur: the SRNC request the DRNC to reserve radio resources for the Radio Link (the DRNC will afterwards reserve these radio resources in the suitable Node-B)- signalling transaction with ALCAP, which will setup a Iur data bearer to carry the Radio Link

Frame ProtocolsAt this stage Data Streams (carrying RABs, NAS signalling, SMS Cell Broadcast service, RRC connection establishment…) have been mapped on transport channels The Frame Protocols (FP) define the structures of the frame and the basic in-band control procedures for every type of transport channels.

ALCAPIt is used to set up AAL2 connections for Data Streams.

BearersData Streams are carried on AAL2, which enables better bandwidth efficiency for user packets but requires its own signalling (ALCAP signalling is used to set up AAL2 connections for Data Streams).RNSAP and ALCAP messages are carried on AAL5.



AAL5 AAL2 AAL2 AAL5 AAL5AAL5AAL5 AAL5 AAL2Phy.(air)

Phy.(air) ATM/Physical layer ATM/Physical layer

... ...NBAP ALCAP

... ...NBAP ALCAP

Soft combining

... ...ALCAPRNSAPIub-FP Iur-FP

MAC

RLC

RRC PDCPBMC

Soft(er) combining

MAC

RLC

RRC PDCPBMC

UE Node-B

SRNC

Softer combining

Iub

Iub-FP

Uu

Radio Protocols

Iu Protocols (Radio Network Layer)

Iu protocols (Transport Network Layer)

Network ProtocolsRecap

1. What is the path of CS traffic through these protocol stacks?1. What is the path of CS traffic through these protocol stacks?

2. Same question for PS traffic?2. Same question for PS traffic?

3. Same question for NAS signalling?3. Same question for NAS signalling?

4. Same question for RRC signalling?4. Same question for RRC signalling?

5. Which protocol is responsible for establishing AAL2 bearers? 5. Which protocol is responsible for establishing AAL2 bearers? what is the path of what is the path of this protocol?this protocol?

6. Which protocol is responsible for the signaling exchange betw6. Which protocol is responsible for the signaling exchange between RNC and Nodeeen RNC and Node--B? What is the path of this protocol?B? What is the path of this protocol?

7. Which protocol is responsible for the signaling exchange betw7. Which protocol is responsible for the signaling exchange between SRNC and een SRNC and DRNC?DRNC?



Network ProtocolsQUIZ!

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

... ... ...

...

...

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

......

...

... ...

CS networks (PSTN, ISDN)

PS networks (internet)...



3.3 Radio Channels



Radio Channels Global Situation

UTRAN SGSN GGSN PDN“Internet”

UMTS Bearer Service External BearerService

UMTS Bearer Service

Radio Access Bearer Service(RAB)

CN BearerService

BackboneBearer Service

Iu BearerService

Radio BearerService

Uu Iu

Teleservice

UE

Logical Channel

Transport ChannelPhysicalChannel

• A Radio Bearer is the service provided by a protocol entity (i.e. RLC protocol) for transfer of data between UE and UTRAN.

• Radio bearers are the highest level of bearer services exchanged between UTRAN and UE.

• Radio bearers are mapped successively on logical channels, transport channelsand physical channels (Radio Physical Bearer Service on the figure)



Radio ChannelsRAB Presentation

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

UTRAN

UEUMTS Bearer

UMTS Bearers

RABs (mapped on Radio & Iu Bearers)

CN-CS

CN-PS

Radio Bearers Iu Bearers

RABRAB

RABRAB

UMTS Bearer

UMTS bearer services

AMR 12.2/12.2, 64/64Conversational (CS)

R2: 64/128, 64/384 64/144, 128/384, 144/384, 32/32, 64/64, 128/128, 144/144

Background (PS)

14.4/14.4Streaming (CS)

Example of available RAB in R4

R2: 64/128, 64/384 64/144, 128/384, 144/384, 32/32, 64/64, 128/128, 144/144

Interactive (PS)



Radio ChannelsRadio Channels, Protocols & Network Elements

RRC

RLC

MAC

BMCPDCP

Physical Layer Physical Layer

NAS Signaling

RRC Sig.

Voice Web Browsing

SMS Cell Broadcast

Radio Bearers

Control Logical Ch.

Traffic Logical Ch.

…Transport Channels

Uu Interface

RNC Node B UE

Physical Channels

MAC

…

Transport Channels

The radio protocols are responsible for exchanges of signalling and user data between the UE and the UTRAN over the Uu interface:-User plane protocolsThese are the protocols implementing the actual Radio Access Bearer (RAB) service,

-i.e. carrying user data through the access stratum (EXAMPLES 1,2 and 4).

-Control plane protocolsThese are the protocols for controlling the radio access bearers and the connection

-between the UE and the network from different aspects including requesting the service

(EXAMPLE 5), controlling different transmission resources, handover & streamlining etc...

Also a mechanism for transparent transfer of Non Access Stratum (NAS) messages is included).

Some principles:

•The Radio Protocols are independent of the applied transport layer technology (ATM in R99): that may be changed in the future while the Radio Protocols remain intact.•The main part of radio protocols are located in the RNC (and in the UE). The Node-B is mainly a relay between UE and RNC.



Radio ChannelsRadio 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 RRC connection 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 is mapped 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.

Please note that RAB (Radio Access Bearer) are only provided in the user plane.

What is a RRC connection?When the UE needs to exchange any information with the network, it must first establish a signalling link with the UTRAN: it is made through a procedure with the RRC protocol and it is called “RRC connection establishment”. During this procedure the UE will send an initial access request on CCCH to establish a signalling link which will be carried on a DCCH.A given UE can have either zero or one RRC connection.



Radio ChannelsLogical Channels (1)

Control Channels (CCH)

Broadcast Control Channel (BCCH)

Traffic Channels (TCH)

Paging Control Channel (PCCH)

Dedicated Control Channel (DCCH)

Common Control Channel (CCCH)

Dedicated Traffic Channel (DTCH)

Common Traffic Channel (CTCH)

UTRAN UELogical Channels

The logical channels are divided into:

•Control channels for the transfer of control plane information

•Traffic channels for the transfer of user plane information



Radio ChannelsLogical 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



Radio ChannelsWhy Transport Channels?

A transport channel offers a flexible pattern to arrange information on any service-specific rate, delay or coding before mapping it on a physical channel:• it provides flexibility in traffic variation• it enables multiplexing of transport channels on the same physical channel

Transport channels provide an efficient and fast flexibility in radio resource management.

Time

Traffic

Time IntervalTransport Channel



Radio ChannelsStructure of a Transport Channel (1)

168

168

168

168

168

360

360 bits

10 ms

Time Transmission Interval (TTI): periodicity at which a Transport Block Set is transferred by the physical layer on the radio interface

10 ms

Transport Block: basic unit exchanged over transport channels.

Transport Format (TF): it may be changed every TTI. Each TF must belong to the Transport Format Set (TFS) of the transport channel

168

168

>> The system delivers one Transport Block Set to the >> The system delivers one Transport Block Set to the physical layer every TTIphysical layer every TTI: what is the delivery bit rate of the : what is the delivery bit rate of the transport blocks to the physical layer during the first TTI?transport blocks to the physical layer during the first TTI?

10 ms 10 ms

• A transport channel is defined by a Transport Format (TF) which may change every Time Transmission Interval (TTI).

• The TF is made of a Transport Block Set. The Transport Block size and the number of Transport Block inside the set are dynamical parameters.

• The TTI is a static parameter.



Radio ChannelsStructure of a Transport Channel (2)

Transport Format (TF)• Semi-static part (can be changed, but long process)

Transmission Time Interval (TTI),Coding scheme...

• Dynamic part (may be changed easily) Size of transport block, Number of transport blocks per TTI

Transport Format Set (TFS)It is the set of allowed Transport Formats for a transport channel, which is assigned by RRC protocol entity to MAC protocol entity.MAC chooses TF among TFS.MAC may choose another TF every TTI without interchanging with RRC protocol (fast radio resource control).

What is TTI (Transmission Time Interval)?

- it is equal to the periodicity at which a Transport Block Set is transferred by the physical layer on the radio interface

- it is always a multiple of the minimum interleaving period (e.g. 10ms, the length of one Radio Frame)

- MAC delivers one Transport Block Set to the physical layer every TTI.



Radio ChannelsTransport Channels: Example

576

576

576

576

576

576

576 bits

576

576

40 ms

3. How many Transport Format(s) may be chosen for this transport3. How many Transport Format(s) may be chosen for this transport channel?channel?

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

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

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

1. Complete the table1. Complete the table

2.2. What is the delivery What is the delivery bit rate of the transport bit rate of the transport blocks to the physical blocks to the physical layer during the first layer during the first TTI?TTI?



Radio ChannelsTransport Channels

Common Channels

Broadcast 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 Transport Channels UE

The transport channels are divided into:

•Common channels: they are divided between all or a group of UEs in a cell. They require in-band identification of the UEs when addressing particular UEs.

•Dedicated channels: it is reserved for a single UE only. In-band identification is not necessary, a given UE is identified by the physical channel (code and frequency in FDD mode)



Radio ChannelsCommon Transport Channels (1)

BCH: Broadcast ChannelA downlink transport channel that is used to carry BCCH. The BCH is always transmitted with high power over the entire cell with a low fixed bit rate.

>> The BCH is the only transport channel with a single transport>> The BCH is the only transport channel with a single transport format (no format (no flexibility). Can you explain why?flexibility). Can you explain why?

PCH: Paging ChannelA downlink transport channel that is used to carry PCCH. It is always transmitted over the entire cell.

>> Is it possible to carry all types of information on the PCH?>> Is it possible to carry all types of information on the PCH?

BCH >high power to reach all the user and low fixed bit rate so that all terminals can decode the data rate whatever its ability: only one Transport Format because there is no need for flexibility (fixed bit rate)

PCH>only two transport channels can NOT carry user information: BCH and PCH.




FACH: Forward Access ChannelA downlink transport channel that is used to carry control information. It may also carry short users packets. The FACH is transmitted over the entire 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>> In which case is it interesting to use beam--forming antennas? would it also be forming antennas? would it also be relevant to implement this feature for PCH?relevant to implement this feature for PCH?

RACH: Random Access ChannelAn uplink transport channel that is used to carry control information from the mobile especially at the initial access. It may also carry short user packets. The RACH is always received from the entire cell and is characterized 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 >> Why is it interesting to carry short user packets on RACH in spite of limited data spite of limited data field and collision risk (instead of using a dedicated channel)?field and collision risk (instead of using a dedicated channel)?

Note: Beam-forming is also called “Inherent addressing of users”: it is the possibility of transmission to a certain part of the cell.

RACH and FACH are mainly used to carry signalling (e.g at the initial access), but they can also carry small amounts of data.

When a UE sends information on the RACH, it will receive information on FACH.




DSCH: Downlink Shared ChannelA downlink transport channel shared by several UEs to carry dedicated control or user information. When a UE is using the DSCH, it always has an associated DCH, which provides power control.

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

⇒ Transfer of signalling and traffic on a shared basis

DSCH and CCPH seem to be symmetrical, but:

- DSCH is on the DL, so that different user data are synchronised with each other (the information on whether the UE should receive the DSCH or not is conveyed on the associated DCH)

- CPCH is on the UL, so that different user data can NOT be synchronised (the mobile phones are not synchronised). It may cause big problem of collisions!



Radio ChannelsDedicated Transport Channels

DCH: Dedicated ChannelA downlink or uplink transport channel that is used to carry user or control information. It is characterized by features such as fast rate change (on a frame-by-frame basis), fast power control, use of beam-forming and support of soft HO.

DCH > It is different from GSM where TCH carries user data (e.g speech frames) and ACCH carries higher layer signalling (e.g HO commands)User data and signalling are therefore treated in the same way from the physical layer (although set of parameters may be different between data and signalling)

> wide range of Transport Format Set permits to be very flexible concerning the bit rate, the interleaving...

> Fast Power Control and soft HO are only applied on this transport channel.



Radio ChannelsMapping Logical⇔Transport Channels

Control Logical Channels

BCCH PCCH CCCH DCCH

Traffic Logical Channels

DTCH CTCH

BCH PCH RACH FACH DSCH CPCH DCH

Common Transport Channels Dedicated Transport Channels



Radio ChannelsMapping Logical ⇔ Transport Channels

Control Logical Channels

BCCH PCCH CCCH DCCH

Traffic Logical Channels

DTCH CTCH

BCH PCH RACH FACH DSCH CPCH DCH

Common Transport Channels Dedicated Transport Channels

According to the slide above and the previous one, we can say state that :

Except BCH and PCH, each type of transport channel can be used for the transfer of either control or traffic logical channels.



Radio ChannelsPhysical Channels

RNC

Node B

IubTransport Channels

For the UE point of view, the network is just the physical channels.

There are several kinds of physical channels.

• Channel associated with transport channel

• UTRAN Signaling (mobility management)

• Core Network Signaling (authentification)

• User Traffic (voice)

There are common and dedicated channels

• Channels not associated with transport channel, the physical signaling.

• Cell Search Selection

• System Information Collection

• Connection Request and Paging Surveillance

These channels and resources allowing the UE to share these channels with other users are the radio resources

We will see later how data from transport channel are processed to be mapped on the physical channels and how a UE uses these channels.



Radio Channels MappingPhysical Channel List

Not associated with transport channels

• CPICH: Common Pilot Channel

• PICH: Page Indicator Channel

• P-SCH & S-SCH: Primary & Secondary Synchronization Channel

• AICH: Acquisition Indicator Channel

Common Physical Channels, associated with transport channels

• P-CCPCH & S-CCPCH: Primary & Secondary Common Control Channel

• PRACH: Physical Random Access Channel

• PDSCH: Physical Downlink Shared Channel

• PCPCH: Physical Common Packet Channel

Dedicated Physical Channels, associated with transport channels

• DPDCH: Dedicated Physical Data Channel

• DPCCH: Dedicated Physical Control Channel



Radio ChannelsPhysical Channels: Structure

15 Time Slots

Radio Frame = 10 ms

N bits (according to the bit rate)

….

1 Time slot = 0.666 ms

A physical channel is defined by:

•A carrier• Some codes (see 4.3 and 4.4 part)• A start and stop instant

Physical channels are sent continuously on the air interface between start and stop instants.

•After channel coding each transport block is split into radio frames of 10 ms.The bit rate may be changed for each frame.

• Each radio frame is also split into 15 time slots. But all time slots belong to the same user (this slot structure has nothing to do with the TDMA structure in GSM).All time slots of a same TDMA frame have the same bit rate.Fast power control may be performed for each time slot (1500 Hz).

• The number of chips for one bit M is equivalent to the spreading factor. It can easilybe computed with knowledge of N:

In fact the spreading factor must be equal to 4, 8, 16…256.Consequently it may be necessary to add some padding bits to match the adequate valueof spreading factor (rate matching).



3.4 UTRAN Radio Protocols



Radio ProtocolsRadio protocol stack

Layer 3

Control plane User plane

Layer 2/MAC

Layer 1Transport Channels

Bearers (called RAB in user plane)Access Stratum

SAP

Non Access Stratum

cont

rol

cont

rol co

ntro

l

PHY

MAC

RRC

Logical Channels

Layer 2/RLC

Radio Bearers

RLC RLCRLCRLC

RLCRLCRLCRLC

PDCPPDCP

BMCcont

rol

control

Layer 2/PDCPLayer 2/BMC

Physical Channels

• The radio protocols are responsible for exchanges of signalling and user data between the UE and the UTRAN over the Uu interface

• The radio protocols are layered into:

- the RRC protocol located in RNC* and UE

- the RLC protocol located in RNC* and UE

- the MAC protocol located in RNC* and UE

- the physical layer (on the air interface) located in Node-B and UE

Two additional service-dependent protocols exists in the user plane in the layer 2: PDCP and BMC.

• Each layer provides services to upper layers at Service Access Points (SAP) on a peer-to-peer communication basis. The SAP are marked with circles. A service is defined by a set of service primitives.

Radio Interface Protocol Architecture is described in 3GPP 25.301.

(*except a part of protocol used for BCH which is terminated in Node-B)



Radio ProtocolsRadio Resource Control (RRC)

cont

rol

cont

rol

cont

rol

PHY

MAC

RRC

RLC

BearersCall management

Radio mobility management

Measurement control and reporting

Outer loop power controlRadio Bearers(control plane)

RRC is the brain of the radio interface protocol stack.

Layer 3

cont

rol

cont

rol

PDCP

BMC

RRC is a protocol which belongs to control plane.

The RRC functions are:

• Call management

RRC connection establishment/release (initial access)

Radio Bearer establishment/release/reconfiguration (in the control plane and in the user plane)

Transport and Physical Channels reconfiguration

• Radio mobility management

Handover (soft and hard)

Cell and URA update (see “5.UTRAN/ Mobility Management”)

Paging procedure

• Measurements control (UTRAN side) and reporting (UE side)

• Outer Loop Power Control

• Control of radio channel ciphering and deciphering

RRC can control locally the configuration of the lower layers (RLC, MAC...) through Control SAP. These Control services are not requiring peer-to-peer communication, one or more sub-layers can be bypassed.

See 3GPP 25.331 RRC protocol (over 500 pages!)



Radio ProtocolsPDCP and BMC protocols

PDCP (Packet Data Convergence Protocol)

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

- 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 radio interface

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

See 3 GPP 25.323 (PDCP protocol) and 25.324 (BMC protocol)



Radio ProtocolsRadio Link Control (RLC)

TrafficLogical

Channels

Radio Bearers(user plane)

Radio Bearers(control plane)

RLC RLCRLCRLC

RLCRLCRLCRLC

ControlLogical

Channels

Segmentation

Buffering

Data transfer with 3 configuration modes:

- Transparent (TM)

- Unacknowledged (UM)

- Acknowledged (AM)

Ciphering

RLC provides segmentation and (in AM mode) reliable data transfer.

Layer 2/upper part

There is no difference between RLC instances in Control and User planes. There is a single RLC connection per Radio Bearer.

RLC main functions:

• RLC Connection Establishment/Release in 3 configuration modes:- transparent data transfer (TM): without adding any protocol information - unacknowledged data transfer (UM): without guaranteeing delivery to the peer entity (but can detect transmission errors)- acknowledged data transfer (AM): with guaranteeing delivery to the peer entity. The AM mode provides reliable link (error detection and recovery, in-sequence delivery, duplicate detection, flow Control, ARQ mechanisms)

ARQ=Automatic Repeat Request (it manages retransmissions)• Transmission/Reception buffer• Segmentation and reassembly (to adjust the radio bearer size to the actual set of transport formats)• Mapping between Radio Bearers and Logical Channels (one to one)

•Ciphering for non-transparent RLC data (if not performed in MAC), using the UEA1, Kasumi algorithm specified in R’99

Encryption is performed in accordance with TS 33.102 (radio interface), 25.413, 25.331(RRC signaling messages) and supports the settings of integrity with CN (CS-domain/PS-domain)

3GPP 25.322 RLC protocol



Radio ProtocolsMedium Access Control (MAC)

Transport Channels

(common and dedicated)

Basic data transfer

Multiplexing of logical channels

Priority handling/Scheduling (TFC selection)

Reporting of measurements

Ciphering

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 each transport channel on a frame basis (each 10 ms) without interchanging with L3-level.

MAC provides flexible data transfer.

TrafficLogical

Channels

ControlLogical

Channels

MACLayer 2/

lower part

MAC belongs to control plane and to user plane.

MAC main functions:

• Data transfer: MAC provides unacknowledged data transfer without segmentation

• Multiplexing of logical channels (possible only if they require the same QoS)

• Mapping between Logical Channels and Transport Channels

• Selection of appropriate Transport Format for each Transport Channel depending on instantaneous source rate.

• Priority handling/Scheduling according to priorities given by upper layers:- between data flows of one UE - between different UEs

Priority handling/Scheduling is done through Transport Format Combination (TFC) selection•Reporting of monitoring to RRC

•Ciphering for RLC transparent data (if not performed in RLC)

3GPP 25.321 MAC protocol



Radio ProtocolsThe Physical Layer

DedicatedPhysical Channels

Multiplexing of transport ch.

Spreading/modulation

RF processing

Power control

Measurements

Physical layer

DedicatedTransport Channels

The physical layer provides multiplexing and radio frequency processing with a CDMA method.

Air Interface

CommonTransport Channels

CommonPhysical Channels

Layer 1

The physical layer belongs to control plane and to user plane.

Physical layer main functions:

•Multiplexing/de-multiplexing of transport channels on CCTrCH (Coded Composite Transport Channel) even if the transport channels require different QoS.

•Mapping of CCTrCH on physical channels

•Spreading/de-spreading and modulation/demodulation of physical channels

•RF processing (3 GPP 25.10x)

•Frequency and time (chip, bit, slot, frame) synchronization

•Measurements and indication to higher layers (e.g. FER, SIR, interference power, transmit power, etc.)

•Open loop and Inner loop power control

•Macro-diversity distribution/combining and soft handover execution

3GPP 25.2xx



CCCHPCCH BCCH CTCH DTCHDCCH DTCH

Radio ProtocolsExercise: MAC protocol (1)

BCCH

FACH RACH DSCH

Iur or local

DCH DCH

MAC-d

MAC-c/sh

CPCHFACHPCH

MAC Control

DSCH

Look at this figure and answer the questions on the following paLook at this figure and answer the questions on the following pages.ges.

MAC-b

BCH




1. On which logical/transport channels will be mapped:- system information broadcasting- paging- telephony speech- internet browsing at a high bit rate- internet browsing at a low bit rateCan you imagine a situation where the UE will use 2 DTCHs (or more) at the same time?

2. Guess the meaning of “MAC-b” “MAC-c/sh” and “MAC-d”.

3. Why is there one MAC-d entity on the UE side and several MAC-d entities on the UTRAN side?

4. What is the link between MAC-c/sh and MAC-d for?

5. What are the 4 main functions of MAC protocol?

6. MAC can multiplex logical channels only if they require the same QoS: true or false?




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 the header of each transport blocks in MAC-c/sh, but not in MAC-d : can you explain the 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 transport channels 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 a DCH?

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?


4. WCDMA in UMTS



4. WCDMA for UMTSSection presentation> Objective: to be able to define a Radio Resource in 3G.

> Program: • 4.1 Context• 4.2 Analogy • 4.3 Spread Spectrum Modulation• 4.4 Code Division Multiple Access• 4.5 Soft HandOver • 4.6 Rake Receiver• 4.7 Power Control• 4.8 Capacity, Coverage & Quality


4. WCDMA in UMTS

4.1 Context



ContextHistorical

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

1996CDMA commercial launch in the USThis system called IS-95 or cdmaOne was developed by Qualcomm 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)

See http://www.cdg.org for IS-95

In CDMA field, we have experience of IS-95

IS-95 vocabulary:forward channel=downlinkreverse channel=uplink handoff=handover



ContextAdvantages & Disadvantages

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

Spectrum efficiency : transmission capacity per spectrum unit (bandwidth), i.e kbit/MHz. This must not be confused with the traffic capacity.The spectrum efficiency in UMTS is higher than in GSM (25x200kHz carriers in GSM offering 335 kbps** while a 5 MHz UMTS carrier offers 400 kbps).If we factor in densification (frequency reuse pattern), the UMTS traffic capacity isdramatically increased. According to CDMA Development Group:“Capacity increases by a factor of between 8 to 10 compared to an AMPSanalog system and between 4 to 5 times compared to a GSM system”


4. WCDMA in UMTS

4.2 Analogy



• Cell

Restaurant room

AnalogyWCDMA and Restaurant

WCDMA Restaurant Room

• UE

People at table

• Code

Language

Enjoy your meal !

Code 1

Code 2

Guten appetite !

Bon appetit !

Bomapetite !

Ues, like people, send and receive on the same time and the same frequency. They are separeted by:

For a table, the conversations of the neighbours are noise, for a UE it is the same principle: neighbour conversations are interference

The equivalence are:

Restaurant room -> Cell

Table -> UE

Language -> Code

Here the important point is all the UEs send and receive on the same time and on the same frequency. The WCDMA is really different because with the GSM, the UEs are separated by the time (TS of TDMA) and the frequency. Here the UEs are separated with codes applied on the signals.

Another important point is for someone the conversation on a neighbour table is considered like noise. It is the same principle with the WCDMA, for a user the other UEs generates some noises.



AnalogyWCDMA and Restaurant


•Node B

Steward

Downlink Enjoy your meal !

Who have order this cake

?

COMO ESTAS ?

????

???

Interference level in DL probleme:

•If some UE use too much power

•If there are too many users in the cell

Impacts:

•Power Control in DL

•Control Admission

Very important !

In downlink,

In the restaurant, the steward want to ask to every table who have order a cake. If some people speak to loud, the table at the back of the room can’t hear the question. It is the same case, if there are too many users in the room.

In the cell, it is the same principle. If there are too many Ues on the cell or if some Ues use too much power, the interference level for a UE far from the Node B is too high to allow the UE decoding the message.



AnalogyWCDMA & Restaurant


It is for me !

Who have order this cake

?

QUIERO LA TARTA !

Es ist meineUplink

C’est à la pomme ?

????

At the Node B level:

• If a UE, close to the NB, speak too loud

•If there are too many users

Probleme of interfence level problem.

The NB can’t decode any users.Impacts:

• Power Control in UL

•Admission Control

Very important

In Uplink, In the restaurant, a steward can understand all the conversation if he knows all the languages.But if on a table, close to him, some one speak to loud the steward can’t understand people on the other tables. It is the same problem if there are too many people it is too noisy to ableable to understand a conversation far from him.With the WCDMA, there is the same problem. That means if the cell is too load, the interference level at the Node B is too high to be able to decode the weakest signal.


4. WCDMA in UMTS

4.3 Spread Spectrum Modulation



Spread Spectrum ModulationA Code as a Shell against Noise

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

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

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.

ReceiverTransmitter

Spreading

Noise

DespreadingRadio Channel



Spread Spectrum ModulationSpectrum spreading

At the transmitter the signal is multiplied by a code which spreads 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 by multiplying the received signal by the same code: you get a peak of correlation, while the noise level due to the radio channel remains the same, because this is not correlated with the code.But the interference level is too high, it is not possible to decode any message.

f

P

f

P

Spreading

Radio channel

f f

P P

Despreading

Interference Level



Spread Spectrum ModulationTransmission Chain

Air Interface

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

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

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

Modulator Demodulator

Code Sequence

Data Data

Code sequence

NB-Signal WB-Signal NB-SignalWB-Signal

Code synchronization between the transmitter and the receiver is crucial for de-spreading the wideband signal successfully.



Spread Spectrum ModulationCode & Spreading factor

The code is applied on each bit of the user data.

The Spreading Factor, called SF, is the length of this code.

Exemple: Data to transmit: 1 0 , SF=8.

1-1

1-1

Spread data

Code

Coded data

Transmission

Reception

Received data, without error

1-1

A chip

Chip rate fixed at 3.86 Mcps

Code applied

1-1

1-1

1-1

What is the spreading factor?It is the number of chips per bit (=chip rate/bit rate).The chip rate is linked with the CDMA carrier bandwidth and has a constant value of 3,84 Mcps. It is quite easy to match the bit rate of the signal with the CDMA chip rate just by choosing theadequate spreading factor.The higher the spreading factor, the more redundancy you add in the signal and the lower theprobability of bit error is by transmitting the signal.It is also traduced by the processing gain (see below).

Code synchronization?It is difficult to acquire and to maintain the synchronization of the locally generated code signal and the received signal. Indeed synchronization has to be kept within a fraction of the chip time.



Spread Spectrum ModulationSpreading factor & Data Rate

The chip rate is fixed, 3.84 Mcps.

If the SF is divided by 2, the dara rate is multiplied by 2 !


Spread data

Code

Coded data

Transmission

Reception

Received data, without error

Code applied

Received data

Small SF = High data rate High SF = Small data rate

1-1

1-1

1-1

1-1

1-1

1-1

The Spreading Factor available are 4, 8, 16, 32, 64, 128, 256 in uplink, plus 512 in downling For signaling at very low bit rate.



Spread Spectrum ModulationSpreading factor & Error at reception (1/2)

When an error occurs at the reception, the determination of the bit value is less trivial.


1-1

1-1

Signal sent on the air Signal received with error

Code

SF=8

Zoom on the decoded

signal

Decoded data

1

-1

0

The determination of the bit value is based on the aera of the received signal.

Here is 3 area unity over 4



Spread Spectrum ModulationSpreading factor & Error at reception (2/2)

1-1

1-1

Signal sent on the air Signal received with error

Code

SF=4

Zoom on the

decoded signalDecoded data

1

-1

0

The determination of the bit value is based on the aera of the received signal.

Here is 2 area unity over 4

With a small SF, the signal is more sensitive to errors. So to have the same error ratio you use more power

If you need a high data rate(video downloading), you will use a small SF. You will have more errors on your message. So if you want to keep the same error ratio, you will use more power to transmit your message

To keep in mind

Another way to understand this relation is with the redundancy.If the SF is small, 4 for example, the useful bit, 0 or 1, is sent just 4 time. The data rate is high.If the SF is higher, 64 for example, the useful bit is sent 64 time. The data rate is smaller.So if an error occurs, it is more significant if the SF is 4 than if the SF is 64.



Spread Spectrum ModulationExercise: Orthogonal Code

Here, there is a received signal and two orthogonal codes

Could you apply these codes on the received signal and determinate which code has been used to spread the signal? What could you conclude about the orthogonality?

Received signal

Code 1

Decoded signal 1

Code 1

Code 2

Code 2

1-1

1-1

1-1

1-1

1-1

1-1

Received signal

Decoded signal 2



Spread Spectrum ModulationWCDMA, Power Density & Processing Gain (1/2)

f

P

RSSI or Io

ISCP or No

SIR

PG

Eb

RSCP or Ec

At Node B reception level

•RSSI: Received Signal Strength Indicator

Total received wideband power over 5 Mhz including thermal noise•ISCP (No): Interference Signal Code Power

Interference on the received signal

•RSCP (Ec): Received Signal Code Power

Unbiaised measurement on the received signal on one channelization code• Eb : energy per useful bit

• PG : Processing Gain = Eb-Ec

Power Gain after despreading. PG= 20 log (Wss/Ws)

WssWs

RSSI: This is the total received wideband (UTRA carrier RSSI) power over 5Mhzincluding thermal noise. It is estimating the uplink interference at the Node B, and by difference with the thermal noise, the rise due to traffic and external interference.



Spread Spectrum ModulationWCDMA, Power Density & Processing Gain (2/2)

f

P

RSSI or Io

ISCP or No

SIR

PG

Eb

RSCP or Ec


SIR: Signal Interference Ratio

NoRSCPSFSIR .

=

•What are the modifications on the diagram if:

•The number of users increases ?

•The SF decreases ?

•The error ratio required decreases ?

Depending on the service, more or less errors are allowed. UTRAN computes theerror ratio and then set the SIR requiredfor the service.


4. WCDMA in UMTS

4.4 Code Division Multiple Access



Code Division Multiple AccessOne-cell reuse

The area is divided into cells, but the entire bandwidth is reused in each cell (frequency reuse of one)

> Inter-cell interference

> Cell orthogonality is achieved by codes

The entire bandwidth is used by each user at the same time

> Intra-cell interference

> User orthogonality is achieved by codes

The rainbows cells mean that the whole bandwidth (5 MHz) is reused in each cell.

In GSM there is also intra-cell interference when there are 2 (or more) TRXs in the same cell. But it is a small problem (as each TRX runs on a different frequency) In CDMA intra-cell interference is an important problem.



Code Division Multiple AccessMultiple 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 ChannelTransmitter 1

The receiver aims at receiving Transmitter 1 only.

Quasi-orthogonal: it is not necessary to have primary colors at the receiver to separate the user. Red and orange for example can also be distinguished.Orthogonality between the codes is impossible to maintain after transfer over the radio interface (multi-path on DL, UEs not synchronized on UL )



Code Division Multiple AccessMultiple access (2)

If a user transmits with a very high power, it will be impossible for the receiver to decode the wanted signal (despite use of quasi-orthogonal codes)

CDMA is unstable by nature and requires accurate power control.

Transmitter 2

Receiver

Radio ChannelTransmitter 1

The receiver aims at receiving Transmitter 1 only.

Spreading 1

Spreading1

Spreading 2

CDMA is instable by nature:

•one user may jam a whole cell by transmitting with too high powerneed for accurate and fast power control

•too many users in one cell would have the same effectneed for congestion control

A CDMA resource has 2 dimensions: the codes and the power. Obviously the power is the limiting factor ; the better we can control the power usage, the more capacity (users) we can allocate.



Code Division Multiple AccessSpreading: Channelization and Scrambling

2chc

3chc

1chc

scramblingc

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.

air interface

Modulator

Spreading consists of two steps:• The channelization code (also called spreading code) transforms every data symbol into a number of chips, thus increasing the bandwidth of the signal. The narrowband signal is spread into a wideband signal with a chip rate of 3.84 Mchips/s. The system must choose the adequate spreading factor to match the bit rate of the narrowband signal.The spreading factor is directly linked with the length of the channelization code.

• The scrambling code does not affect the signal bandwidth: it is only a chip-by-chip operation.The scrambling code is cell-specific on the downlink and terminal-specific on the uplink.



Code Division Multiple AccessChannelization Codes (Spreading Codes)

The channelization codes are OVSF (Orthogonal Variable Spreading Factor) codes: • their length is equal to the spreading factor of the signal: they can 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 one cell

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 by several users (usually one code tree per cell)

What is a channelization code?• OVSF (Orthogonal Variable Spreading Factor)• Length: 4-256 chips according to the spreading factor(in downlink also 512 chips is possible to match very low bit rate) • Number of codes:The channelization codes can be defined in a code tree, which is shared by several users.If one code is used by a physical channel, the codes of underlying branches may not be used.The number of codes is consequently variable: the minimum is 4 codes of length 4, the maximum is 256 codes of length 256. The channelization code (and consequently the spreading factor) may change on a frame-by-frame basis

How is Code Allocation managed?The codes within each cell are managed by the RNC.No need to coordinate code tree resource between different base stations or terminals.Usually one code tree per cell. If two code trees are used, it is necessary to use the secondary scrambling code.



Code Division Multiple AccessScrambling 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 search procedure)

The long scrambling codes are truncated to the 10 ms frame length.

Only one DL scrambling code should be used within a cell.Another scrambling code may be introduced in one cell if necessary (example : shortage of channelization code), but orthogonality between users will be degraded.

In fact, there are two types of scrambling codes:• Long codes:

•Gold codes constructed from a position wise modulo 2 sum of 38400 chip segments of two binary sequences (generated by means of 2 generators polynomials of degree 25)•used with Rake Receiver : the PRACH is constructed from the longscrambling sequences. There are 8192 PRACH preamble scrambling codes in total, divided into 512 groups of 16 each.

• Short codes: •Length : 256 chips•used with advanced multi-user detector•likely to be used later

Refer to Technical Specification 3GPP TS 25.213


4. WCDMA in UMTS

4.5 Soft Handover



Soft HandoverIntroduction

Principle: As the UEs are separated by codes, they send and receive data all on the same time and on the same frequency and one frequency is used in a set of adjacent cells, the soft handover is possible.

A UE is in case of Soft Handover when it is linked to several cells on the same time.

So , in donwlink, the UE receives several time the same data and combine them toincrease the quality. In Uplink, several cells and Node can receive the same message and combines them to increase the quality.

Soft Handover doesn’t exist in GSM, it is not possible because there are different frequencies in a set of adjacent cells.

Interest: Like the quality of the signal is increased after the reception, it is possible to use less power. That allows to save the interference level. If this interference level is too high, it is not possible to decode the data and the call is cut.



Soft HandoverScenarios: Softer Handover

Iu

Core Network

Iubs Iubs

Iur

Iu

Serving RNC

Serving RNC (SRNC1): on UL it collects information from the Drift RNC and from its ownNode-B and performs selection of the signal on a best frame quality basis. On DL it duplicates Iu-information to Drift RNC and to its own Node-B and recombination of the signal is performed by the UE. There may be only one Serving RNC per UE.

Drift RNC (DRNC2): it performs the routing of information from/to the Serving RNC.There may be up to 4 Drift RNC(s) per UE.



Soft HandoverScenarios: Soft Handover

Iu

Core Network

Iubs Iubs

Iur

Iu

Serving RNC

Serving RNC (SRNC1): on UL it collects information from the Drift RNC and from itsown Node-B and performs selection of the signal on a best frame quality basis.On DL it duplicates Iu-information to Drift RNC and to its own Node-B and recombinationof the signal is performed by the UE. There may be only one Serving RNC per UE.




Soft HandoverScenarios: Soft Handover inter RNC

Iu

Core Network

Iubs Iubs

Iur

Iu

Serving RNC Drift RNCIur

Serving RNC (SRNC1): on UL it collects information from the Drift RNC and from itsown Node-B and performs selection of the signal on a best frame quality basis. On DL it duplicates Iu-information to Drift RNC and to its own Node-B and recombination of the signal is performed by the UE. There may be only one Serving RNC per UE.




IurIur

Soft HandoverScenarios: SRNC Relocation

Iu

Core Network

Iubs Iubs

Iu

Serving RNC Drift RNC

Iu

Serving RNC

Serving RNC (SRNC1): on UL it collects information from the Drift RNC and from its own Node-B and performs selection of the signal on a best frame quality basis.On DL it duplicates Iu-information to Drift RNC and to its own Node-B and recombination of the signal is performed by the UE. There may be only one Serving RNC per UE.




Soft HandoverSoft Handover & Code Management

Iu

Core Network

Iubs

Serving RNC

In Downlink, • Scrambling Code

One DL SC per Cell

• Channelization Code

One DL CC per radio link to avoid having the same code sequence on 2 radio link

In Uplink, • Scrambling Code

One UL SC per UE

• Channelization Code

One UL CC per service (per physical channel).

Cell A Cell B

DL SC cellA

DL CC1 user 1

DL SC cellB

DL CC2 user 1

UL SC eqUL CC user

The UE sends one signal which can receive by several cell.

The UE receives several signals

Conclusion:



Soft HandoverCost & Benefit

Why do we need soft HO?Imagine that a UE penetrates from one cell deeply into an adjacent cell:

it may cause near-far effecthard HO is not a good solution, due to the hysteresis mechanism

Better spatial repartition of the power, so lower interference level

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.



> Soft Handover execution:• 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.

• 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

• The UE needs to get the following information– Channelization & scrambling codes to be used– Relative timing information (Timing offset based on CPICH

synchro)

Soft HandoverCost & Benefit


4. WCDMA in UMTS

4.6 Rake Receiver



Rake ReceiverRake Receiver principle (1)

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

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

A Rake receiver is capable to decode several signals simultaneously in the so called “fingers” and to combine them in order to improve the quality of the signal or to get several services 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 are carrying the services)- soft handover - path diversity

“A single carrier”: in fact each operator may use several carriers of 5MHz each (2 in Germany, 3 in France) The rake receiver can only be used with signals on the same carrier.



Rake ReceiverRake receiver principle (2)

The components of the multi-code signal are demodulated in parallel 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 2Delay 2

Delay 3

Data 2

1stFinger

2ndFinger

3rdFinger

Data 1

Multi-code signal

Delay Adjustment

Rake fingers are allocated to the peaks at which significant energy arrives. Update rate: tens of ms

Each finger tracks the fast-changing phase and amplitude values due to fast fading and removes them

Rake Receiver resides in both UE and Node-B.

The numbers of fingers for a Rake Receiver is implementation dependant.



Rake ReceiverRake Receiver and Multi-Service

As a first approach, we can say:

One service, one code! (*)

Multimedia receiverTransmitter

Spreading 1 Despreading 1

Radio ChannelSpreading 2

Despreading 2

>> Which codes make it possible to >> Which codes make it possible to separate the two signals at the receiver?separate the two signals at the receiver?

* we will see later that it is also possible to multiplex several services on the same code! Indeed on a dedicated physical channel (which is identified by its spreading code) a user can multiplex several services as long as the total bit rate of the services does not exceed the bit rate of the physical channel.See subchapter 5.UTRAN/ Physical Layer (Transport Channel Multiplexing)



Rake ReceiverRake Receiver and soft handover

Soft handover is possible, because the two mobile stations use the same frequency band. The mobile phone need only one transmission 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 to >> Which codes make it possible to separate the two signals at the separate the two signals at the receiver?receiver?



Rake ReceiverRake Receiver and path diversity (1)

Natural obstacles (buildings, hills…) cause reflections, diffractions and 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 duration 0,26 µs (78 m) of the CDMA system.

If the delay dispersion is greater than the chip duration, the multipathcomponents of the signal can be separated by a Rake Receiver.

In this case, CDMA can take advantage of multipath propagation.

What is multipath propagation?The signal travels from transmitter to receiver over different paths, due to reflections, diffractions or scattering. Consequently the same signal arrives at the receiver with a little delay.

The chip rate can be considered as the resolution of the CDMA system. It is linked with the 5 MHz carrier.



Rake ReceiverRake Receiver and path diversity (2)

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

ReceiverTransmitter

Spreading Despreading

Direct path

Reflected path

ReceiverTransmitter

Spreading Despreading

Direct path

Reflected path

Dispersion <Chip durationThe Rake Receiver cannot provide path diversity. >> Which codes make it >> Which codes make it

possible to separate the two possible to separate the two signals at the receiver?signals at the receiver?

Multi-path propagation usually reduces the quality of the signal.

But in most cases a Rake Receiver can take advantage of multi-path to improve the quality of the signal. Indeed the dispersion is often greater than the chip duration.

Note: with IS-95 (cdmaOne), the carrier bandwidth is about 1 MHz and the chip duration is consequently longer: 1 µs (300 m). Multi-path components can not be separated in urban areas with IS-95.


4. WCDMA in UMTS

4.7 Power Control



Power ControlWhy ?

Iub

Serving RNC

Main Problem : If the interference level is to high, it is not possible to decode the signal.

f

P

ISCP or NoSIR

PG

Eb

RSCP or Ec


In UTRA/FDD, the power control is a key functionality : the users usingsimultaneously the same frequency band interfere each other.The transmit power must be dynamically adapted in order to

Enable to reach the quality of serviceCompensate fading occurrencesAvoid interfering other users (and thus decreasing the system capacity)

Two main power control algorithms can be distinguished:Open-loop power control (UL only)Closed loop power control (UL/DL)



Power ControlDifferent kinds of Power Control

Physical channels:

• Not associated with transport channels

(Physical signaling)

• Associated with transport channels

• Dedicated channels

• Common channels

Channel power fixed and set by the operator

Open Loop Power Control

Closed Loop power control



Power ControlOpen Loop

If UE receives a STRONG DL signal,then UE will speak low.

1

2

1

2

If UE receives a weak DL signal,then UE will speak LOUD.

Fading is not correlated on UL and DL due to separation of UL and DL band.Open loop Power Control is not enough fast and accurate for the dedicated traffic.

Open Loop Power Control

Basic mechanism:PC is intended to reduce the interference level in the system by maintaining the quality if theUE-UTRAN radio link as close as possible to the minimum quality required for thetype of service requested.

How is Power Control performed ?- Open loop power control (also called slow power control):it consists for the mobile station of making a rough estimate of path loss by means of aDL beacon signal and adding the interference level of the Node-B and a constant value.It’s far too inaccurate and only used to provide a coarse initial power setting of the mobilestation at the beginning of a connection

- Closed-loop power control:See next slide



Power ControlClosed Loop PC : Principles

IubRNC

Outer Closed Loop Inner Closed Loop

• SIR Estimation

• Comparaison between SIRestand SIRtarget

• Generation of a TCP command: increase or descreaseOn each Time slot !

1500 Hz...

”Power down”

”Power up”

”Power down”

”Power ...”

***

***

***

***

***

SIR target

Error measurements

The Node-B controls the power of the UE (and vice versa) by performing a SIR estimation (inner loop) and by generating TPC command for each time slot of the radio frame.

The RNC controls parameters of the SIR estimation (outer loop) and set the initial SIR target, defined by the operator and modify it according to the error measurement reports.

Closed Loop Power Control

Inner Loop (Fast Loop Power Control)In UL, the serving cells should estimate signal-to-interference ratio SIRest

of the received uplink DPCH. The serving cells should then generate TPC commandsand transmit the commands once per slot according to the following rule: if SIRest > SIRtarget

then the TPC command to transmit is "0" , while if SIRest < SIRtarget then the TPC command to transmit is "1".Upon reception of one or more TPC commands in a slot, the UE shall derive a singleTPC command, TPC_cmd, for each slot, combining multiple TPC commands if morethan one is received in a slot. TPC_cmd values = +1(power up), -1 (power down), 0The step size ∆TPC is under the control of the UTRAN (value = 1 dB or 2 dB)UE shall adjust the transmit power of the uplink DPCCH with a step of ∆DPCCH (in dB)which is given by ∆DPCCH = ∆TPC × TPC_cmd.The command rate of 1500Hz is faster than any significant change of path loss.

Outer Loop The RNC checks the quality of the signal using for example a CRC-based approach(Cyclic Redundancy Check) and uses this result to adjust SIR target for the inner loop.The big issue is to meet constantly the required quality: no worse and also no better,because it would be a waste of capacity. The required quality may change with the multi-path profile (related to the environment)and with the UE speed.The outer loop management is handled by the CRNC because a soft HO may be performed.Frequency of the outer loop: 10-100 Hz typically

Note: in GSM only slow power control is employed (about 2 Hz)



Power ControlClosed Loop PC : Power Density

f

P

ISCP or No

SIR estEb

RSCP or Ec


Assuming a user using a service.

It is initial SIR target is 3dB.

The error ratio required is 0.01 .

Several error ratio reports are between 0.002 and 0.007

How do the SIR target evoluate ?

What is the impact on the user or on the system if the estimated SIR is too high ? Too small ?

Iub

RNC

SIR target

Error measurements...

”Power up”

”Power ...”

SIR Target



Power ControlUL Closed Loop PC, in case of Soft Handover

Iub

What is the behaviour of the UE in UL in case of soft handover ?

• The UE takes in to account all the command according to the 3GPP

P(t)=P(t-1) + F(TPC1(t) + TPC2(t))

The function F(TPC(t)) is implemented by the UE manufacturer.

F(TPC(t))=min(TCP1(t), …, TPCi(t))

With i= number of involved Node B

Power up !!! TPC=1

Power down !!! TPC=-1

???

1 2



Power ControlDL Closed Loop PC, in case of Soft Handover

Iub

What is the behaviour of the Node B involedin the call in DL in case of soft handover ?

• The UE sends the same command for all the Node B involved.

Node Bs must transmit data with the same power for a user

• Due to reception errors their power can shift themselves

A mechanism, the DL Power Balancing, allows to readjust the transmission power of the Node B.

The SRNC selects the best radio link, and readjust, step by step, the transmission power.

P(t) = P(t-1) + Ptpc(t) + Pbal(t)

Power up !!! TPC=1

Power up

Power up


4. WCDMA in UMTS

4.8 Coverage, Capacity & Quality



Coverage, Capacity & QualityLinks between the Coverage, the Capacity and the Quality

Example: Increase the quality in UL

How to do ?

• Decrease the error ratio at the Node B level

• So increase the SIR at the Node B level

• So the UEs use more power

Impacts !

• Increasement of the UL Interference level

• So decrease of the cell size

• And decrease of the high data rate with need more power in transmission (capacity).

RNC

Node B

Iub

f

P

SIR



Coverage, Capacity & QualityImprovement Ways

•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 and coverage.•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 base stations.•Receive antenna diversitythe base station collects the signal on two uncorrelated branches. It can be obtained by space or polarization diversity.•Base stations algorithmse.g. accuracy of SIR estimation in power control process

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 the CN)



Coverage, Capacity & QualityTypical Values

Quality: The quality is measured with the Block Error Ratio (BLER). Here some example according different services.

Coverage:

• Dense Urban Cell: about 300 meters

• SubUrban Cell: about 1 km

•Rural Cell: 3 km

Capacity:

The main limitation is the interference level due to the WCDMA technology.

But the system is also limited by capacity processing of the Node B and the RNC, by the codes, and by the transmission capacity.

0.10.01 0.01

DCCH

0.01

PS384

0.01

PS128

0.01

PS64

0.01 0.001

CS64

0.001

AMR

Target BLER


5. UTRAN Scenario



UTRAN ScenarioContent

> Objective: to be able to build the map of the radio channels (logical, transport and physical) from a white paper.

> Program:

• 5.1 Radio Channels Mapping • 5.2 Service Request• 5.3 RAB Establishment• 5.4 Mobility Management in connected mode



UTRAN ScenarioIntroduction 1/3

Iub

Serving RNC

CNCollection of System Informatin

System Information

RRC Connection

RRC ConnectionIMSI Attachment

IMSI Attachment

Paging

Paging

The UE is switched on !

What happen ?




Iub

Serving RNC

CN

The UE requests a service.

How and in which conditions are the resources required setup ?

Admission Control

? RAB Establishment

RAB

Traffic Managment




Iub

Serving RNC

CN

The UE uses a service and moves !

How UTRAN can provide the service despite the mobility ?

A new radio is added

Hard Handover on anthere FDD carrierInter RAT Handover

BSCBTS


5. UTRAN Scenario

5.1 Radio Channels Mapping



Radio Channels MappingDownlink

Logical Ch

Transport Ch

Physical Ch

AICHNot associated with transport channels PICH CPICH P-SCH S-SCH

PDSCH S-CCPCH P-CCPCHDPDCH

+ DPCCH

DTCH, DCCH CCCH, CTCH

DCH BCHPCHFACHDSCH

Not implemented yet in EvoliumTM

Solution

PCCH BCCH

DPDCH and DPCCH multiplexed by time

Common Physical ChDedicated Physical Ch



Radio Channels MappingUplink

Logical Ch

Transport Ch

Physical Ch

PRACH PCPCHDPDCH +

DPCCH

DTCH, DCCH CCCH

DCH1 RACHDCH2

CCTrCH

CPCH

DPDCH and DPCCH multiplexed by modulation

Dedicated Physical Ch Common Physical Ch


5. UTRAN Scenario

5.2 Service Request



Service RequestContent

> Program:

• 5.2.1 System Information Collection• 5.2.2 RRC Connection• 5.2.3 IMSI Attachment & Location Update• 5.2.4 Paging


5. UTRAN Scenario

5.2 Service Request5.2.1 System Information Collection



System Information CollectionPrinciples

Iub

Serving RNC

CN• The UE synchronize itself at the slot on the P-SCH

• UE synchronize itself at the frame level on the S-SCH and retrieve a group of 8 Scrambling codes.

•The UE test the 8 SC on the CPICH to find the SC of the cell

•The UE decode the BCH channel to read the system information

•The UE select the best cell

???

Just after the switch on, the UE can decode only the P-SCH and S-SCH if it is on acovered area



System Information CollectionP-SCH & S-SCH

P-CCPCH Radio Frame 10 ms

Slot #0 Slot #1 Slot #14

acpP-SCH

S-SCH acs1

…acp acp

acs2 acs14

The SCH is time-multiplexed with the P-CCPCH (which carries the BCH) and consists of 2 sub-channels.

• The Primary SCH (P-SCH) made of always the slot on all the FDD Cells. The UE uses it to acquire the slot synchronization to a cell.

•The Secondary SCH (S-SCH) contains a sequence of 15 codes which identifies the Code Group of the Downlink Scrambling Code (DL SC) of the cell. The UE uses it to acquire the frame synchronization to a cell and to identify the Code Group of the DL SC.

256 chips

Cell Search Procedure (also called synchronization procedure)3GPP TS 25.214 provides an informative description how it is typically done

Step 1: slot synchronizationIn all the cell of any PLMN, the P-SCH is made of a unique & same primary codesequence of 256 chips repeated at each Time Slot Occurrence.This is typically done with a single matched filter (or any similar device) to the primarysynchronisation code which is common to all cells. The slot timing of the cell can beobtained by detecting peaks in the matched filter output.

Step 2: frame synchronization and code-group identificationA S-SCH is made of 15 repetitions of a secondary code sequence of 256 chips(one per Time Slot) transmitted in perfect synchronization with the P-SCHcode sequences. The UTRAN used 64 distinct secondary synchronization code sequences (reused in distant cells of the UTRAN).This is done by correlating the received signal with all possible secondary synchronisationcode sequences, and identifying the maximum correlation value. Since the cyclic shifts of thesequences are unique the code group as well as the frame synchronisation is determined.

Each secondary code sequence corresponds to a unique group of 8 possible Primary Scrambling codes

Step 3: (downlink) scrambling code identificationThe UE determines the (primary) scrambling code used by the found cell throughsymbol-by-symbol correlation over the CPICH (pilot) with all codes within the Code Groupidentified in the step 2 (8 possibilities). Afterwards the P-CCPCH can be detected and the system- and cell specific BCHinformation can be read.



System Information CollectionCPICH

…Slot #0 Slot #1 Slot #14

Pre-defined symbol sequence

CPICH (Common Pilot CHannel)•The pilot carries a pre-defined symbol sequence at a fixed rate.

•It is a reference:

• To aid the channel estimation at the terminal (time or phase reference)

• To perform handover measurements and cell selection/reselection (power reference)

• The UE tests the 8 DL SC of the Group Code. The DL SC which allows to retrieve the pre-define sequence is the DL SC of the cell.

SF=256 Tslot=2560 chips 20 bits

The CPICH has the following characteristicThe same channelization code is always used for the P-CPICH,The P-CPICH is scrambled by the primary scrambling code,There is one and only one P-CPICH per cell,The P-CPICH is broadcast over the entire cell.



System Information CollectionSystem Information Broadcast

The broadcast system information:• May come from CN, RNC or Node-B. • Contains static parameters (Cell identity, supported PLMN types...) and dynamic parameters (UL interference level...).• Is arranged in System Information Blocks (SIB), which group together elements of the same nature.

Some exemple:•SIB1: Core Network Information •SIB3: Cell Selection, Access Restriction•SIB7: UL Interference•SIB11: Measurement

CN

LA, RA …

DL SC, Power Control info

UL interference level

Example of SIB:

MIB: Master Info Block (structure & scheduling of SIBs)SIB 1: NAS System Information + TimerSIB 2: URA (not supported) +Timer SIB 3: Cell Selection/Reselection and Access RestrictionSIB 5: Common channel Information (P-CCPCH, S-CCPCH, RACH) and AICH/PICH power offsetSIB 7: UL Interference and PRACH parameter SIB 11:MeasurementsSIB 18:PLMN Identity of neighboring cells



System Information CollectionSystem Information Broadcast

The broadcast system information can be carried on BCH which is transmitted permanently over the entire cell.

Transport Ch.

Logical Ch.

Physical Ch.

BCCH

BCH

P-CCPCH

The broadcast system information is made of 128 periodic radio frame. So its period is 1280 ms. There are a Master SIB or MIB and several SIB (System Information Block) organised by domain.

Frame #0 Frame #1 Frame #2

Frame #i-1 Frame #i Frame #i+1

Frame #125 Frame #126 Frame #127

MIB SIB3 SIB11

SIB5 SIB7 MIB

SIB5SIB11 SIB7

…

……

…

Thanks to this channel, the UE is able to retrieve information allowing the request of a RRC connection like the Channelization code used on the uplink common channel



System Information CollectionProcedure

System Information Update Request

Master/Segment Info Block(s), BCCH modification time

Master/Segment Info Block(s)System Information (BCCH:BCH)

UE Node-B RNC

RRC RRC

NBAP

CN


RRC RRC


RRC RRC

System Information Update Response

NBAP NBAP

>> Why does RRC protocol >> Why does RRC protocol terminate at Nodeterminate at Node--B for BCH B for BCH

(not at RNC)?(not at RNC)?

NBAP



System Information CollectionRadio Channel Mapping: P-CCPCH

The Primary CCPCH carries the BCH, which provides system- and cell-specific information (e.g set of uplink scrambling codes)The P-CCPCH is a fixed rate 30 kbps DL physical channel, which provide a timing reference for all physical channels (directly for DL, indirectly for UL).CCPCH is scrambled under the Primary Scrambling code.

Slot #0 Slot #1 Slot #13 Slot #14Slot #i

SCH

Tslot=2560 chips

20 bits

256 chips

How many bits are there for BCH ?

P-CCPCH Primary Control Common Channel



Cell SelectionPrinciples

Iub

RNC

CN

???

Now, the UE can read the BCH of one cell.

But this cell is not necessary the best because the SCH has been chosen randomly.

The UE compares the cells to be camped on the best one.

There are 2 criterion:

• QRxLev, from the CPICH RSCP, to estimate the reception level.

• Qqual, from the CPICH Ec/No, to estimate the quality of reception. It takes in account the interference level.

When a UE is not connected, like here, and is moving, it has to reselect regularly the best cell for itself. To protect some cells, it is possible to facilitate or not the selection of one cell.


5. UTRAN Scenario

5.2 Service Request5.2.2 RRC Connection



RRC ConnectionWhy ?

The UE is switched on and has selected a cell.

The UE is in idle mode.

•UTRAN doesn’t know anything about this UE.

•The UE hasn’t UTRAN identifier neither Scrambling and Channelization code.

The UE can’t exchange any data with UTRAN.

To be known by UTRAN and to use dedicated radio resources, the UE has to be RRC connected.

After, the UE can attach its IMSI or update its location to the Core Network and can request a service

Iub

RNC

CN

RRC Connected



RRC ConnectionProcedure: RRC Connection Establishment

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

UE

RRC RRC

3. Radio Link Establishment

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 information5. RRC Connection Setup Complete (DCCH:RACH or DCH)

RRC RRC

2. Allocate RNTI, Select Level 1 and Level 2

parameters (e.g. TFCS, scrambling code)

>> Can the UE send user information (e.g voice call) after compl>> Can the UE send user information (e.g voice call) after completing this stage?eting this stage?

Node-B RNC

1. UE initiates set-up of an RRC connectionInitial UE identity: e.g TMSI Establishment cause: e.g traffic class

2. RNC decides which transport channel to setup (RACH/FACH or DCH) and allocates

RNTI (Radio Network Temporary Identity) and radio resources (e.g TFS, TFCS, scrambling

codes) for this RRC connection.

3. A new radio link must be setup. This is done via a signalling procedure between RNC

and Node-B which is managed by NBAP protocol (see “Procedure D” for more detail).

4. Logical, transport and physical channel configuration are sent to the UE.

5. RRC Connection Setup Complete message is sent:

- on RACH in case of RRC connection on RACH/FACH (cell_FACH state)

- on DCH in case of RRC connection on DCH (cell_DCH state)



RRC ConnectionProcedure: RRC Connection Release

RRC RRC4. RRC Connection Release (DCCH:DCH )

Cause

RANAP RANAP

1. Iu Release Command

Cause

RANAP RANAP

2. Iu Release Complete

-

3. ALCAP Iu Bearer Release

RRC RRC5. RRC Connection Release Complete (DCCH:DCH )

-

6. Radio Link Deletion



UE Node-B(DRNC)

SRNCDRNC CNNode-B(SRNC)

In this example, the UE is in macro-diversity on two Node-Bs from two different RNCs.

Therefore the UE could only be in cell_DCH state (soft HO is only possible on DCH)

1. The CN initiates the release of RRC connection

2. -

3. SRNC initiates release of Iu Bearer using ALCAP protocol

4. -

5. -

6. SRNC initiates release of radio link (for Node-B of SRNC) using NBAP protocol

7. SRNC requires release of radio link (for Node-B of DRNC) to DRNC using RNSAP protocol

8. DRNC initiates release of radio link (for Node-B of DRNC) using NBAP protocol



RRC ConnectionHow to contact UTRAN: the PRACH Channel 1/2

Iub

RNCFor the initial access, the UE has to use a common uplink channel called the PRACH

Every UE use this channel to request a connection. If 2 UEs request on the time there is collision, and UTRAN receives nothing.

To manage this problem, the UE sends a first message called preamble until it receives a response on a downlink channel called AICH.

After the response on the AICH, the UE sends its message (the request) on the PRACH.

Hello !

Preamble on the PRACH

Yes ! Response on the AICH

HELLO!I need a connection

Message part

PRACH= Physical Random Access ChannelAICH= Acquisition Indicator channel



RRC ConnectionHow to contact UTRAN: the PRACH Channel 2/2

Preamble

Preamble

Message part

DPp,mPO

Reception of AICH

POP

PRACH channel

The first preamble is sent with the power P.

The UE resends a preamble until it receives a response on the AICH.

At each time, it increases the power of the preamble by the Power Offset paramenter (PO)

UTRAN can’t receive its preamble if:

• The power is not enough high

• There is a collision with another user.

In the message part, there is the RRC connection request.



RRC ConnectionUE Status 1/3

UE

detached

UE

in idle mode

UE

in connected

mode

RRC Connection Release

RRC Connection Establishment

out of coverage

“just after switch on” process

Including Cell search procedure

Just after the switch on, the UE has to attach its IMSI. Thanks to his procedure the Core Network knows, the UE is on the network and where it is located at the Location or routing area level.

Several sub-status in the connected

mode

To attach its IMSI and update its location the UE has to be in connected mode, so it has to request a RRC Connection

•Just after switch on” process contains:•Cell selection (including cell search procedure) •PLMN selection•Attachment procedure (see “Appendix” for more details)

• The UE must enter the connected mode to transmit signalling or traffic data to the network

•What is the relationship with the states of the mobile phone in GSM?

The two GSM states, idle mode and connected mode, are similar to idle mode and cell_DCH state in UMTS.

•What is the relationship with the states of the mobile phone in GPRS?

There is no correspondence between GPRS states (idle, standby and ready) and UMTS states.

Indeed there is no notion of connection on GPRS.




Cell DCH

Cell FACH

URA PCH

Cell PCH

UE

in idle

mode

UE in connected mode

Cell_DCH state

Signalling and traffic data dedicated to the UE (mapped on DCCH and DTCH respectively) are carried on DCH transport channel

Cell_FACH state

Signalling and traffic data dedicated to the UE (mapped on DCCH and DTCH respectively) are carried 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 too large

•The initial state of the UE is determined by the DCCH established during RRC connection establishment:- if the DCCH is mapped on a DCH, the UE is in cell_DCH state- if the DCCH is mapped on RACH/FACH, the UE is in cell_FACH state

• The UE can move from one state to another during the time of the RRC connection.• Transitions between states are:

- based on traffic volume measurements and network load

- always triggered by UTRAN signalling

Note: in cell_DCH state, the DSCH transport channel can also be used.




Cell DCH

Cell FACH

URA PCH

Cell PCH

UE

in idle

mode

UE in connected mode

Cell_PCH state

No transmission of signalling and traffic data dedicated to the UE (no DCCH and no DTCH)

But the RRC connection is still active (UTRAN keeps RNTI for UE) and UE location at a cell level.

- a DCCH (and possibly a DTCH) can be reestablished very quickly (this procedure is initiated by sending a paging signal PCH)

URA_PCH state

Very similar to cell_PCH state

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

Cell_PCH ⇒ Cell_FACH ⇒URA_PCHToo many cell reselections

Cell_FACH ⇒Cell_PCHNo traffic UL/DL at expiry of timer 2

Cell/URA_PCH ⇒ Cell_FACHIncoming DL or UL traffic

•URA: UTRAN Registration Area (a small set of cells)

•Cell_PCH and URA_PCH states are needed for non real time services to optimise usage

of codes and battery consumption. It would not be efficient to allocate permanently a DCH

which would be used a very low percentage of time (Web application for example)

• What is the difference between idle mode, Cell_PCH and URA_PCH states?

In idle mode the location of the UE is not known by the UTRAN, but only by the CN at a

Location Area (LA) or Routing Area (RA) level (LA and RA and sets of cells larger than URA.

The paging message PCH must hence be sent in a LA or in a RA when the UE is in idle mode,

whereas it only needs to be sent in a cell in Cell_PCH state or in an URA when the UE is in

URA_PCH state (hence the paging procedure is much faster).


5. UTRAN Scenario

5.2 Service Request5.2.3 IMSI Attachment & Location

Update



IMSI Attachment & Location UpdateInitial Attachment

HLR SGSNMSC/VLR

MSC/VLR SGSN

Iub

RNCThe UE has selected a cell.

It had to declared its identity and its location (LA & RA) to the Core Network.

So, it requests a RRC connection to send to the Core Network information about its situation.

The parameters are mainly the LA, the RA and its IMSI

LA1/RA2

LA=Location Area= Set of cells for the CS CNRA= Routinf Area= Set of cells for the PS CN



IMSI Attachment & Location UpdatePrinciples

When camping on a cell, the terminal must register its LA and/or its RA.

When the terminal moves across the network, it must update its LA (RA) which is stored in VLR (SGSN) in the Core Network.

LA (RA) Update is performed periodically or when entering a new LA (RA).

HLRSGSNMSC/VLR

Location Area (LA)

Routing Area (RA)

MSC/VLR SGSN

•LA and RA are managed on an independent way, but a RA must always be included in one LA(and not be divided into several different LAs).

• LA update is performed by the NAS layer MM (Mobility Management) located in UE and in MSC. • RA update is performed by NAS layer GMM (GPRS Mobility Management) located in UE and in SGSN.

• In the Core Network, the location information is stored on databases:- HLR (Home Location Register)It stores the master copy of user’s service profile, which consists of information on allowed services,forbidden roaming areas,… and which is created when a new user subscribes to the system.The HLR also stores the serving system (MSC/VLR and/or SGSN) where the terminal is located.

- VLR (Visitor Location Register)It serves the terminal in its current location for CS services and holds a copy of the visitinguser’s service profile.It stores the Location Area (LA) where the terminal is located.

- SGSN (Serving GPRS Support Node)It serves the terminal in its current location for PS services and holds a copy of the visitinguser’s service profile.It stores Routing Area (RA) where the terminal is located.



IMSI Attachment & Location UpdateProcedure: Direct Transfer

RANAP RANAP1. Direct Transfer

CN Domain Indicator, NAS PDU

RRC RRC

2. Downlink Direct Transfer (DCCH:FACH or DCH)

NAS message

RANAP RANAP2’. Direct TransferCN Domain Indicator,

NAS PDU

RRC RRC

1’. Uplink Direct Transfer (DCCH:RACH or DCH)CN node indicator, NAS message

UE Node-B SRNC CN

Use mainly for the IMSI attachment, location update and the authentification between the UE and the Core Network

UE must be in cell_FACH or in cell_DCH states.


5. UTRAN Scenario

5.2 Service Request5.2.4 Paging



Paging Principle

Iub

RNC

Iub

RNC

Iub

RNC

Core Network

Called number

HLRMSC/VLR MSC/VLR Paging message with the IMSI of the

called UE

Location Area

Some one is calling me, I request a RRC

connection



Paging Procedure 1: UE in Connected Mode

RANAP RANAP1. Paging

CN Domain Indicator, UE identity, Paging cause

RRC RRC

UE Node-B SRNC CN

2. Paging Type 2 (DCCH:FACH or DCH)

In this case the UE is already connected and is using a service (voice call, web-browsing …). The Core Network knows the situation of the UE and mainly its Serving RNC. The CN contacts directly the Serving RNC.

The RNC doesn’t use the PCCH and the PCH but the channel used for the UE, dedicated or common, according to the status of the UE.

UE is in cell_FACH or in cell_DCH states:

1. CN initiates the paging of a UE to Serving RNC

2. Paging of UE with Paging Type 2 (on DCCH) using the existing RRC connection



Paging Procedure 2: UE in Idle Mode

RRC RRC2. Paging Type 1 (PCCH:PCH)

RRC RRC2. Paging Type1 (PCCH:PCH)


CN Domain Indicator, UE identity, Paging cause


Idem

UE1 UE2 Node-B1 Node-B2 RNC1 RNC2 CN

When the is in idle mode, UTRAN doesn’t know where it is located and the Core Network knows its location at the LA or RA level. UTRAN uses the PCCH and the PCH radio channels.

UE is in idle mode:

1. CN initiates the paging of a UE over a LA (RA in PS domain) spanning, for example, two RNCs.

2. Paging of UE with Paging Type 1

LA: Location Area, RA: Routing Area (see subchapter “5.8 Mobility Management”)

A similar procedure applies to UE in cell_PCH or in URA_PCH states.



Paging Radio Channels: PICH & PCH

Iub

RNC

PICHS-CCPCH

PCH

PCCHThe UE doesn’t watch the S-CCPCH.

It watches the PICH (Page Indicator Channel) at regular and defined interval and look for its PI, for Paging Indicator.

The PI is baseb on the IMSI. Several UEs can have the same PI.

When the UE find its PI on the PICH, it watches the S-CCPCH to check if it is for it and what is the cause.

Then it requests on RRC connection to have a RAB.

Logical Ch

Transport Ch

Physical Ch

MAC

Physical layer

In RNC

In Node B

PICHS-CCPCH

.

PI

PI

PI

..Paging message


5. UTRAN Working

5.3 RAB Establishment



Procedure between the switching on and the request of a serviceContent

> Program:

• 5.3.1 Admission Control• 5.3.2 RAB Establishment


5. UTRAN Working

5.3 RAB Establishment5.3.1 Admission Control



Admission ControlIntroduction

According to the previous part “WCDMA in UMTS”, if the interference level at the Node B level is too high, the Node B can’t decode all the signal. The size of the cell decreases. The interferences are due to several causes:

• The radio environment and the load of the adjacent cells,

• Some users use too much power, the power control manages this problem,

• There are too many users on the the cells

UTRAN has to check if there is enough UL radio resource

Iub

RNC

f

P

ISCP = NoSIR

PG

Eb

RSCP = Ec


SIR too small to retrieve the message

2 others questions before adding a new user : Is there sufficient DL radio resource andsufficient processing resources ?



Admission ControlPrinciples

Is there sufficient UL Radio Resource -> Rx RAC

If UL interference level + estimated new user contribution < threshold

Then Rx RAC ok

Is there sufficient DL Radio Resource -> Tx RAC

If Total DL Tx Power + estimated new user contribution < threshold

Then Tx RAC ok

Is there sufficient processing resource -> Processing RAC

3 main points are checked:

• the channelization codes

• The BB board capacities limited 1702.3 kbps

•The DSP (in BBs) load

•The number of user and radio links limited respectively to 64 users and 90 RLs

RAC = Radio Access Control


5. UTRAN Working

5.3 RAB Establishment5.3.2 Radio Bearers Establishment



Radio Bearers EstablishmentIntroduction

Signaling

Core NetworkIub

Node B

RNC

UTRAN

RAB

Radio Bearer Iu Bearer

Logical Channel

RLC

Transport Channel

MAC

Physical Channel

Phy.

RLC Mode: Tr., UM or AM and retranmission parameter for AM

TTI, TFS, TFCS, CRC, FEC, Coding Rate, Rate Matching

Frequency, Power, Channelization & Scrambling codes

RRC

Configured by

We have seen how a UE, after the switch on, can collect system information, update its location, request a RRC Connection and a service, can be paged and how UTRAN allows it to use services. Now how are established the RAB ?




Radio Bearers EstablishmentSignaling: RAB Establishment

RANAP RANAP

1. RAB Assignment Request

RAB parameters, User plane mode, Transport Address, Iu

Transport association

2. ALCAP Iu Data Transport Bearer Setup

3. Radio Link Establishment(see Procedure D)

RRC RRC4. RB Setup (DCCH:FACH or DCH )

TFS, TFCS...

RRC RRC5. RB Setup Complete (DCCH:RACH or DCH )

-

RANAP RANAP

6. RAB Assignment Response

-

UE Node-B SRNC CN

The UE is RRC connected and has requested a service.




Radio Bearers Establishment Signaling: RL Setup

Cell id, TFS, TFCS, frequency, UL scrambling code, power control info

Radio Link Setup RequestNBAP NBAP

Signalling link termination, transport layer addressing info

Radio Link Setup ResponseNBAP NBAP

Downlink synchronisationIub-FP Iub-FP

Uplink synchronisationIub-FP Iub-FP

Start RX

Start TX

>> Are NBAP, ALCAP and RRC messages carried on the same transpor>> Are NBAP, ALCAP and RRC messages carried on the same transport bearers ont bearers on IubIub??

Node-B SRNC

ALCAP Iub Data Transport Bearer Setup

RAC = Radio Access Control•This procedure is used in many RRC procedures, e.g RRC connection

establishment (Procedure C1), Radio Bearer Set-up (Procedure F1), soft HO (Procedure G)…

• In this procedure:

a radio link is set up by the RNC on the Node-B side using the NBAP protocol

(a similar task is performed on the UE side using RRC protocol, see e.g. procedure C1)

a terrestrial link (AAL2 bearer) is setup on Iub interface using ALCAP protocol



Radio Bearers EstablishmentPhysical Layer Processing

Convolutional coding, Turbo coding

10 ms frame duration15 time slots

CCtrCH

DPDCH, DPCCH, PRACH...

Channelization codesScrambling codes

QPSK

Channel Coding

Radio Frame Segmentation

Transport Channel Multiplexing

Physical Channel Mapping

Spreading

Modulation

Physical Channels spread over 5 MHz bandwidth

Layer 1



Radio Bearers Establishment Radio Channels

Assuming a UE a visio call service. What happens in Uplink ?

RLC

MAC

Physical Layer

Radio Bearer

Logical Ch. DTCH

Transport Ch. DCH

Physical Ch. DPDCH/DPCCH

UE

CN

RLC parametersRAB :64 kbps

MAC parametersMode : Transparent because it is a real time service

CRC = 16 bits, FEC = Turbo Code Coding Rate = 1/3, TTI= 40 ms, TFS=(0*640, 4*640 bits)

640

640

640

640

640

640

640

640

640

640

640

640

TTI

How many radio frame are necessary to send all this data ?




Radio Bearers Establishment Radio Channels: Data Processing

Assuming a UE a visio call service. What happens in Uplink ?

#1 #4…#1 #4…

Transport Blocks

CRC attachment

Tr Bl concatenation

Turbo coding (1/3)

Tail Bit Attachment

1 st interleaving

Radio Frame Segmentation

Rate matching

640 bits 16

(640+16)*4=2624 bits

2624*3=7872 bits

2624*3=7872 bits12

7884 bits

#1 #4…1971 1971

#1 #4…1971 +Nrm 1971 +Nrm

Can you deduce the SF ?

And the value of Nrm ?




Radio BearersEstablishment Radio Channels: Transport Channel Multiplexing

Assuming a UE a visio call service and on the same time sends on a e-mail.

How can it be possible to send 2 different services on the same physical channel ?

Several transport channels can be time-coordinated to be multiplexed on a CCTrCHbefore mapping on one physical channel

MAC

TFC Selection

L1

TrCH Multiplexing

Phy. Ch. Mapping

CCTrCH

Physical Channel

DCH1 DCH2

Example:

TFS (DCH1)={(0*640); (4*640)}

TFS(DCH2)={(1*0); (1*39); (1*42); (1*55); (1*65)}

TFCS={(0*640); (1*0)}; {(0*640); (1*39)}; {(0*640); (1*42)}; {(0*640); (1*55)}; {(0*640); (1*65)}; {(1*640); (1*39)}; {(1*640); (1*42)}

MAC selects TFC inside TFCS.

There is one TFCS per CCTrCH

Transport Format

Transport Format Combination

TFS= Transport Format SetTFCS=Transport Format Combination SetTF=Transport Format



Radio Bearers Establishment Radio Channels: DPDCH & DPCCH

Uplink

Downlink



Data : user data, RRC Signaling & NAS Signaling DPDCH

DPCCH Pilot TFCI FBI TPC

Multiplexed by the modulation

Data1 TPC Data2 TFCI Pilot

DPDCH DPCCH DPDCH DPCCH DPCCH

Time-multiplexed


5. UTRAN Scenario

5.4 Mobility Management in connected mode



Mobility Management in connected modeContent

> Program:

5.3.1 Soft Handover5.3.2 Compressed Mode 5.3.3 Hard Handover5.3.4 Inter RAT Handover


5. UTRAN Scenario

Soft Handover



Soft HandoverActive & Monitoring Set

Iub

RNC

Cell in the Active Set

Cell in the Monitoring Set

The RNC manages the Active Set and builds the Monitoring Set.

The Monitorin Set is built from the information of topology and design in the RNC.

The Active Set is managed from the event send by the UE to the RNC.

The maximum number of cells in the monitoring set is 32.The maximum number of cells in the active set is set from the Office Data, between 3 and 6.



Soft HandoverEvents

Iub

RNC


Cell in the Monitoring Set

There are 3 events for the soft handover. The value measured is the CPICH Ec/No.

The event 1a is triggered when the CPICH Ec/No of a monitored cells is above a certain threshold.

The event 1b is triggered when the CPICHEc/No of a monitored cells is below a certain threshold.

The event 1c is triggered when the active set has reached its maximum size and the CPICH Ec/No of a monitored cells is better than a cell belonging to the active set.



Compressed Mode

Iub

RNC


Cell in the Monitoring Set, same FDD frequency

Cell in the Monitoring Set, other FDD frequency

Cell in the Monitoring Set, GSM cell

The most of the UE are not dual receiver. And they need to perform measurement an other frequencies.

So UTRAN has to free it some time to perform these measurements on other FDD frequencies or on GSM frequencies.

The main method is to divide the SF of certain frame by 2, so it divides the length of the frame by 2.

Time interval to measure other frequencies



Hard Handover on other FDD FrequenciesEvents

Iub

RNC





There are 4 events to watch the UMTS cell with other FDD frequencies

The event 2d_cm is triggered when the quality of on the current frequency is below a certain quality. The compressed mode is launched.

The event 2b is triggered when the quality of the current frequency is below a certain threshold and the quality on an other frequency is above a certain threshold

The event 2f is triggered when the quality on the current frequency is above a certain threshold. The compressed mode is desactivited.



Hard Handover on other GSM FrequenciesEvents

Iub

RNC





2 causes can trigger an hard HO toward the GSM system:

• Some bad radio conditions

• due to the service requested

The event 2d_cm is triggered when the quality of on the current frequency is below a certain quality. The compressed mode is launched.

The event 3a is triggered when the quality on the current FDD frequency is below a certain threshold and the quality on the GSM is above another threshold.

The event 3c is triggered when the service requested can be managed by the GSM, the voice typically.



Exercise 1/3

Objectives: Rebuilt the channels mapping, Logical, Transport and Physical, from a scenario to guide you with the 2 next pages

Scenario:

• The UE switches on in a covered area.

•The UE collects information about the system

•The UE request a RRC connection to declare its location and releases the RRC connection

•The UE receives a paging message to receive an e-mail.

•UTRAN establishes a RAB and is in the DCH_Cell State

•Like the traffic is not large, the UE pass to the FACH_Cell State.

Be careful, following this scenario, some channels are missing. Which are the missing channels ?



Exercise 2/3Downlink

Logical Ch

Transport Ch

Physical Ch



Exercise 3/3Uplink

Logical Ch

Transport Ch

Physical Ch


Appendix



Appendix

• “Just after switch on” process

• AMR codec

•NBAP elementary procedures

•RANAP elementary procedures



PLMN selection

Cell selection

Attachment2

1 After switch on, the UE:

- scans the entire frequency bandwidths of UTRAN FDD and GSM (cell search procedure for UTRAN FDD )

- monitors the broadcast channels (BCCH for UTRAN FDD) to get the PLMN identifiers.

Hence the UE can establish a list of PLMNs which are available in its location.

List of availablePLMNs

UE switche

d on

1

In the list of available PLMNs, the UE selects:

- the HPLMN (Home PLMN) if it is available

- otherwise another PLMN (national or international) according to priority rules possibly stored in the USIM

Selected PLMN2

“Just after switch on” processPLMN Selection



“Just after switch on” processAttachment Procedure

PLMN selection

Cell selection

Attachment

3

4

In the selected PLMN, the UE:

- selects the best cell according to radio criteria

- initiates attachment procedure on the selected cell

Attach-ment

request 3

During the attachment procedure (called IMSI attachfor CS domain, GPRS attach for PS domain), the UE indicates its presence to the PLMN for the purpose of using services:

- authentication procedure

- storage of subscriber data from the HLR in the VLR (or in the SGSN for PS domain)

- allocation of the TMSI (P-TMSI for PS domain)

Attach-mentresult

4

5

Indication of service to the UE

The result of the procedure is notified to the UE:

- if successful, the UE can access services

- if it fails, the UE can only perform emergency calls

5



AppendixAMR codecs

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 the CN)

AMR mode Source coding bit-rate ClassA

ClassB

ClassC

AMR_12.20 12.20 kbit/s (GSM EFR) 81 103 60AMR_10.20 10.20 kbit/s 65 99 40AMR_7.95 7.95 kbit/s 75 84 0AMR_7.40 7.40 kbit/s (IS-641) 61 87 0AMR_6.70 6.70 kbit/s (PDC-EFR) 58 76 0AMR_5.90 5.90 kbit/s 55 63 0AMR_5.15 5.15 kbit/s 49 54 0AMR_4.75 4.75 kbit/s 42 53 0



Appendix/NBAP elementary procedures NBAP elementary procedures

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

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

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

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

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

•Measurements on Common Resources. This function allows the CRNC to initiate measurements in 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 a Radio 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.

NBAP Functions (see 3GPP 25.433)

T a b l e 1 : M a p p i n g b e t w e e n f u n c t i o n s a n d N B A P e l e m e n t a r y p r o c e d u r e s

F u n c t i o n E l e m e n t a r y P r o c e d u r e ( s )C e l l C o n f i g u r a t io n M a n a g e m e n t a ) C e l l S e t u p

b ) C e l l R e c o n f i g u r a t io nc ) C e l l D e l e t i o n

C o m m o n T r a n s p o r t C h a n n e l M a n a g e m e n t a ) C o m m o n T r a n s p o r t C h a n n e l S e t u pb ) C o m m o n T r a n s p o r t C h a n n e lR e c o n f i g u r a t i o nc ) C o m m o n T r a n s p o r t C h a n n e l D e l e t i o n

S y s t e m I n f o r m a t io n M a n a g e m e n t S y s t e m I n f o r m a t io n U p d a t eR e s o u r c e E v e n t M a n a g e m e n t a ) B l o c k R e s o u r c e

b ) U n b l o c k R e s o u r c ec ) R e s o u r c e S t a t u s I n d ic a t i o n

C o n f i g u r a t io n A l i g n m e n t a ) A u d i t R e q u i r e db ) A u d i tc ) R e s e t

M e a s u r e m e n t s o n C o m m o n R e s o u r c e s a ) C o m m o n M e a s u r e m e n t I n i t i a t i o nb ) C o m m o n M e a s u r e m e n t R e p o r t i n gc ) C o m m o n M e a s u r e m e n t T e r m i n a t i o nd ) C o m m o n M e a s u r e m e n t F a i l u r e

R a d i o L i n k M a n a g e m e n t . a ) R L S e t u pb ) R L A d d i t i o nc ) R L D e le t i o nd ) U n s y n c h r o n i s e d R L R e c o n f i g u r a t i o ne ) S y n c h r o n i s e d R L R e c o n f i g u r a t i o nP r e p a r a t i o nf ) S y n c h r o n i s e d R L R e c o n f i g u r a t io n C o m m i tg ) S y n c h r o n i s e d R L R e c o n f i g u r a t i o nC a n c e l l a t i o nh ) R a d i o L in k P r e - e m p t i o n

R a d i o L i n k S u p e r v i s io n . a ) R L F a i l u r eb ) R L R e s t o r a t i o n

C o m p r e s s e d M o d e C o n t r o l [ F D D ] a ) R a d i o L in k S e t u pb ) R a d i o L in k A d d i t i o nc ) C o m p r e s s e d M o d e C o m m a n dd ) U n s y n c h r o n i s e d R a d i o L i n k R e c o n f ig u r a t i o ne ) S y n c h r o n i s e d R a d i o L i n k R e c o n f i g u r a t i o nP r e p a r a t i o nf ) S y n c h r o n i s e d R a d i o L i n k R e c o n f ig u r a t i o nC o m m i tg ) S y n c h r o n i s e d R a d i o L i n k R e c o n f i g u r a t i o nC a n c e l l a t i o n

M e a s u r e m e n t s o n D e d i c a t e d R e s o u r c e s a ) D e d ic a t e d M e a s u r e m e n t I n i t i a t i o nb ) D e d ic a t e d M e a s u r e m e n t R e p o r t i n gc ) D e d ic a t e d M e a s u r e m e n t T e r m i n a t i o nd ) D e d ic a t e d M e a s u r e m e n t F a i l u r e

D L P o w e r D r i f t i n g C o r r e c t i o n [ F D D ] D o w n l i n k P o w e r C o n t r o lR e p o r t i n g o f G e n e r a l E r r o r S i t u a t i o n s E r r o r I n d i c a t i o nP h y s i c a l S h a r e d C h a n n e l M a n a g e m e n t [ T D D ] P h y s i c a l S h a r e d C h a n n e l R e c o n f i g u r a t i o nD L P o w e r T i m e s l o t C o r r e c t i o n [ T D D ] D o w n l i n k P o w e r T i m e s l o t C o n t r o l



Appendix/RANAP elementary procedures RANAP elementary procedures

•Relocating serving RNC. This function enables to change the serving RNC functionality as well as the related Iuresources (RAB(s) and Signalling connection) from one RNC to another.

•Overall RAB management. This function is responsible for setting up, modifying and releasing RABs.

•Release of all Iu connection resources. This function is used to explicitly release all resources related to one Iuconnection.

•SRNS context forwarding function. This function is responsible for transferring SRNS context from the RNC to the CN for intersystem forward handover in case of packet forwarding.

•Controlling overload in the Iu interface. This function allows adjusting the load in the Iu interface.

•Sending the UE Common ID (permanent NAS UE identity) to the RNC. This function makes the RNC aware of the UE's Common ID.

•Paging the user. This function provides the CN for capability to page the UE.

•Transport of NAS information between UE and CN. This function has three sub-classes:

•Controlling the security mode in the UTRAN. This function is used to send the security keys (ciphering andintegrity protection) to the UTRAN, and setting the operation mode for security functions.

•Controlling location reporting. This function allows the CN to operate the mode in which the UTRAN reports the location of the UE.

•Data volume reporting function. This function is responsible for reporting unsuccessfully transmitted DL data volume over UTRAN for specific RABs.

RANAP Functions (some of them (see 3GPP 25.413))

S u c c e s s f u l O u t c o m e U n s u c c e s s f u l O u t c o m eE l e m e n t a r yP r o c e d u r e

I n i t i a t i n gM e s s a g e R e s p o n s e m e s s a g e R e s p o n s e m e s s a g e

I u R e l e a s e I U R E L E A S EC O M M A N D

I U R E L E A S E C O M P L E T E

R e l o c a t i o nP r e p a r a t i o n

R E L O C A T I O NR E Q U I R E D

R E L O C A T I O N C O M M A N D R E L O C A T I O NP R E P A R A T I O N F A I L U R E

R e l o c a t i o nR e s o u r c eA l l o c a t i o n

R E L O C A T I O NR E Q U E S T

R E L O C A T I O N R E Q U E S TA C K N O W L E D G E

R E L O C A T I O N F A I L U R E

R e l o c a t i o nC a n c e l

R E L O C A T I O NC A N C E L

R E L O C A T I O N C A N C E LA C K N O W L E D G E

S R N S C o n t e x tT r a n s f e r

S R N S C O N T E X TR E Q U E S T

S R N S C O N T E X TR E S P O N S E

S e c u r i t y M o d eC o n t r o l

S E C U R I T YM O D EC O M M A N D

S E C U R I T Y M O D EC O M P L E T E

S E C U R I T Y M O D E R E J E C T

D a t a V o lu m eR e p o r t

D A T A V O L U M ER E P O R TR E Q U E S T

D A T A V O L U M E R E P O R T

C n I n f o r m a t i o nB r o a d c a s t

C NI N F O R M A T I O NB R O A D C A S TR E Q U E S T

C N I N F O R M A T I O NB R O A D C A S T C O N F I R M

C N I N F O R M A T I O NB R O A D C A S T R E J E C T

R e s e t R E S E T R E S E T A C K N O W L E D G E

R e s e t r e s o u r c e R E S E TR E S O U R C E

R E S E T R E S O U R C EA C K N O W L E D G E

E le m e n ta r y P ro c e d u re M e s s a g eR A B R e le a s e R e q u e s t R A B R E L E A S E R E Q U E S TIu R e le a s e R e q u e s t IU R E L E A S E R E Q U E S TR e lo c a t io n D e te c t R E L O C A T IO N D E T E C TR e lo c a t io n C o m p le te R E L O C A T IO N C O M P L E T ES R N S D a ta F o rw a rd in g In it ia tio n S R N S D A T A F O R W A R D C O M M A N DS R N S C o n te x t F o rw a rd in g fro mS o u rc e R N C to C N

F O R W A R D S R N S C O N T E X T

S R N S D a ta F o rw a rd in g to T a rg e tR N C fro m C N

F O R W A R D S R N S C O N T E X T

P a g in g P A G IN GC o m m o n ID C O M M O N IDC N In v o k e T ra c e C N IN V O K E T R A C EC N D e a c t iv a te T ra c e C N D E A C T IV A T E T R A C EL o c a tio n R e p o r tin g C o n tro l L O C A T IO N R E P O R T IN G C O N T R O LL o c a tio n R e p o r t L O C A T IO N R E P O R TIn it ia l U E M e s s a g e IN IT IA L U E M E S S A G ED ire c t T ra n s fe r D IR E C T T R A N S F E RO v e r lo a d C o n tro l O V E R L O A DE rro r In d ic a tio n E R R O R IN D IC A T IO N



Appendix/RSNAP elementary procedures RSNAP elementary procedures

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

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

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

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

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

•DL Power Drifting Correction [FDD]. This function allows the SRNC to adjust the DL power level of 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 between the 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 utilise Common Transport Channel Resources within the DRNS (excluding DSCH resources for FDD);

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

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

Fun ct ion Ele m e n t a ry Proce du re ( s) Radio Link Managem ent a) Radio Link Setup

b) Radio Link Addit ion c) Radio Link Delet ion d) Unsynchronised Radio Link Reconfigurat ion e) Synchronised Radio Link Reconfigurat ion Preparat ion f) Synchronised Radio Link Reconfigurat ion Com m it g) Synchronised Radio Link Reconfigurat ion Cancellat ion

Physical Channel Reconfigurat ion Physical Channel Reconfigurat ion Radio Link Supervision a) Radio Link Failure

b) Radio Link Restorat ion Com pressed Mode Control [ FDD] a) Radio Link Setup

b) Radio Link Addit ion c) Com pressed Mode Com m and d) Unsynchronised Radio Link Reconfigurat ion e) Synchronised Radio Link Reconfigurat ion Preparat ion f) Synchronised Radio Link Reconfigurat ion Com m it g) Synchronised Radio Link Reconfigurat ion Cancellat ion

Measurem ents on Dedicated Resources a) Measurem ent I nit iat ion b) Measurem ent Report ing c) Measurem ent Term inat ion d) Measurem ent Failure

DL Pow er Drif t ing Correct ion [ FDD] Dow nlink Pow er Control CCCH Signalling Transfer a) Uplink Signalling Transfer

b) Dow nlink Signalling Transfer Paging Paging Com m on Transport Channel Resources Managem ent

a) Com m on Transport Channel Resources I n it iat ion b) Com m on Transport Channel Resources Release

Relocat ion Execut ion Relocat ion Com m it Report ing of General Error Situat ions Error I ndicat ion



Related Documentation

Abbreviations and Acronyms



Related documentation

English- WCDMA for UMTS, Harri Holma and Antti Toskala, Wiley 2000, ISBN 0 471 72051 8

- UMTS Mobile communications for the future, Wiley 2001, ISBN 0 471 49829 7

- Alcatel Telecommunications Review, 1st Quarter 2001 (“Find your way with 3G”)

- 3GPP specifications: ftp://ftp.3gpp.org/Specs/ftp://ftp.3gpp.org/Specs/

Francais- UMTS les réseaux mobiles de troisième génération, Editions Eyrolles 2001 (translation of “WCDMA for UMTS” )

- UMTS les origines, l'architecture, la norme, Pierre Lescuyer, Editions Dunod 2001, ISBN 2 10 005195 4

- Revue des Télécommunications d’Alcatel , 1er trimestre 2001 (entièrement consacrée à la 3G)



Abbreviations and Acronyms (1)

AAL ATM Adaptation LayerACELP Algebraic Code Excited Linear PredictionADN Abbreviated Dialling NumberALCAP Access Link Control Application PartAMR Adaptive Multi RateATM Asynchronous Transfer ModeBCCH Broadcast Control ChannelBCH Broadcast ChannelBHCA Busy Hour Call AttemptsBER Bit Error RateBLER Block Error RateBMC Broadcast / Multicast ControlBM-IWF Broadcast Multicast InterWorking

FunctionBSC Base Station Controller BSS Base Station (sub)System BTS Base Transceiver Station CAMEL Customized Application for Mobile

Enhanced LogicCC Call Control

CCCH Common Control ChannelCCTrCH Coded Composite Transport ChannelCDMA Code Division Multiple AccessCDR Call Detail Record CN Core NetworkCPCH Common Packet ChannelCRNC Controlling RNCCS Circuit SwitchedCTCH Common Traffic ChannelDCA Dynamic channel AllocationDCCH Dedicated Control ChannelDCH Dedicated ChannelDHO Diversity HandOverDHT Diversity HandOver TrunkDRAC Dynamic Resource Allocation ControlDRNC Drift RNCDS Direct SequenceDSCH Downlink Shared ChannelDTCH Dedicated Traffic Channel




EDGE Enhanced Data rates for GSM EvolutionERAN EDGE Radio Access Network (all-IP)FACH Forward Access ChannelFBI FeedBack InformationFDD Frequency Division DuplexFDD-DS FDD-Direct Sequence (FDD1)FDD-MC FDD-Multiple Carrier (FDD2)FER Frame Error RateFP Frame ProtocolFTP File Transfer Protocol GERAN GSM/EDGE Radio Access NetworkGGSN Gateway GPRS Support NodeGPRS General Packet Radio ServiceGSM Global System for Mobile CommunicationsGSN GPRS Support Node (ie SGSN or GGSN)GTP GPRS Tunneling ProtocolGTP-U GPRS Tunneling Protocol-User PlaneHO HandOverHPLMN Home PLM

IETF Internet Engineering Task Force IMEI International Mobile Equipment IdentityIMSI International Mobile Subscriber IdentityIP Internet ProtocolIR Incremental RedundancyISDN Integrated Services Digital NetworkL1,L2,L3 Layer 1, Layer 2, Layer 3LA Location AreaLCS Location ServicesLLC Logical Link ControlLQC Link Quality ControlM3UA SS7 MTP3 User Adaptation layerMAC Medium Access ControlMBS Multi-standard Base StationMC Multiple CarrierMExE Mobile Execution EnvironmentMM Mobility Management MSC Mobile-services Switching CenterMSP Multiple Subscriber Profile




MTP3 Message Transfer Part (broadband)MTP-3B Message Transfer Part level 3NAS Non Access StratumNBAP Node-B Application PartODMA Opportunity Driven Multiple AccessOSA Open service ArchitectureOTDOA-IPDL Observed Time Difference of Arrival

Idle Period DownlinkOVSF Orthogonal Variable Spreading FactorPCCH Paging Control ChannelPCH Paging ChannelPDA Personal Digital AssistantPDC Personal Digital Cellular (2G Japan)PDP Packet Data ProtocolPDU Protocol Data UnitPLMN Public Land Mobile NetworkPRACH Physical Random Access Channel

PS Packet SwitchedQOS Quality Of Service QPSK Quadrature Phase Shift KeyingRA Routing AreaRAB Radio Access BearerRACH Random Access ChannelRAN Radio Access NetworkRANAP RAN Application PartRB Radio BearerRL Radio LinkRLC Radio Link ControlRNC Radio Network ControllerRNS Radio Network Sub-System RNSAP RNS Application PartRNTI Radio Network Temporary IdentityRRC Radio Resource ControlRRM Radio Resource Management




SAP Service Access PointSAT SIM Application ToolkitSDU Service Data UnitSF Spreading FactorSGSN Serving GPRS Support Node SHO Soft HandOverSIR Signal to Interference RatioSMS Short Message ServiceSPU Signaling Processing UnitSRNC Serving RNCSSCOP Service Specific Connection Oriented

ProtocolSSCP Signaling Connection Control PartSTM Synchronous Transfer ModeTC TranscoderTCP Transport Control ProtocolTD-CDMA Time Division & CDMATDD Time Division DuplexTDMA Time Division Multiple Access

TF Transport Format TFC Transport Format Combination TFCI Transport Format Combination IndicatorTFCS Transport Format Combination SetTFS Transport Format SetTMSI Temporary Mobile Station IdentityTPC Transmission Power ControlUDP User Datagram ProtocolUICC UMTS Integrated Circuit CardUMTS Universal Mobile Telecommunication

SystemUSIM UMTS Subscriber Identity Card USSD Unstructured Supplementary Service

DataURA UTRAN Registration AreaURAN UMTS Radio Access Network (ETSI)

Universal Radio Access Network (3GPP)USB Universal Serial BusUTRAN UMTS Terrestrial Radio Access Network




VC Virtual ChannelVHE Virtual Home EnvironmentVoIP Voice over IPVP Virtual PathWAP Wireless Application ProtocolW-CDMA Wideband Code Division Multiple

AccessWIM WAP Identity Module



Abbreviations and Acronyms (Standard Organizations)

3GPP 3rd Generation Partnership Project (WCDMA)3GPP2 3rd Generation Partnership Project 2 (cdma2000)3GIP 3rd Generation partnership for Internet Protocol ANSI American National Standard Institute (USA)ARIB Association of Radio Industries and Business (Japan)CWTS China Wireless Telecommunication Standard groupETSI European Telecommunication Standard InstituteIETF Internet Engineering Task ForceIMT International Mobile TelecommunicationITU International Telecommunication UnionT1 Committee T1 telecommunication of the ANSI (USA)TIA Telecommunication Industry Association (USA)TTA Telecommunication Technology Association (Korea)TTC Telecommunication Technology Committee (Japan)UWCC Universal Wireless Communications CommitteeW3C World Wide Web Consortium

umts introduction 1

Documents

context alcatel university

training alcatel university

umts goals1

page 2contents1 introduction1

umts services principles2

umts bearer services2

standardizationthe umts

successful introduction