UMTS Network Systems Overview Day 2

8/13/2019 UMTS Network Systems Overview Day 2

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1U101 UMTS Network Systems Overview

UMTS Network Systems

Overview

Day 2


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Locator Slide

Introductory Session

1st and 2nd Generation CellularSystems Overview

3rd Generation Drivers andStandards

CDMA Mobile TechnologyOverview

UMTS Architecture Overview

UMTS Air Interface

Day 1 Roundup

Day 2 Introd uct ory Session

UTRAN

UMTS Core Network

UMTS Fixed Network Interfaces

UMTS Mobiles

UMTS Services

Course Roundup

Day 2 Introductory Session


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Summary of Yesterday

Yesterday we looked at 1st and 2nd Generation Cellular Systems

Drivers for 3rd Generation Cellular

CDMA and Mobile Technology

An Overview of UMTS Architecture

The UMTS Air Interface



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Today

Today we are going to look at: UTRAN

The UMTS Core Network

The UMTS Fixed Network Interfaces

UMTS Mobiles

UMTS Services



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Locator Slide






UMTS Air Interface

Day 1 Roundup


UTRAN

UMTS Core Network


UMTS Mobiles

UMTS Services

Course Roundup

UTRAN


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8/1728U101 UMTS Network Systems Overview

Contents and Session AimsUTRAN

This session aims to explain the

roles and procedures behindUTRAN

To describe in detail the entitiescomprising the UTRAN

To examine the role of UTRAN

in Soft Handover To look at Call Admission,

Congestion control and RadioResource ManagementAlgorithms

To look at how the air interface

is affected by power controlalgorithms

UTRAN

RNS, RNC and Node-BHandover in UMTS

Transmit DiversityCell Search and

SynchronisationPower Control

Admission ControlLoad Control

Radio ResourceManagement



UTRAN

UTRAN is the UMTS Terrestrial Radio Access Network

For any network UTRAN consists of: One or more RNSs with their associated RNCs, Node Bs and Cells

The functions of UTRAN (as described above) are:

System access control Security and privacy

Handover

Radio resource management and control

UTRAN



Radio Network Subsystem (RNS)

A Radio Network Subsystem

consists of:A single RNC

One or more Node Bs

Cells belonging to Node Bs

The UMTS equivalent of theGSM BSS

RNC

Node

B

Cell

Cell

Cell

Node

B

Cell

Cell

Cell

Iur

Iu

Uu

UTRAN



Radio Network Controller (RNC)

Responsible for the use and

integrity of the radio resourceswithin the RNS

Responsible for the handoverdecisions that require signallingto the UE

Provides a combining/splittingfunction to support macrodiversity between different NodeBs

UTRAN

RNC

Node

B

Cell

Cell

Cell

Node

B

Cell

Cell

Cell

IurIu

Uu



Node B

Logical node responsible for

radio transmission / reception inone or more cells to/from theUE

Dual mode Node B can supportFDD and TDD mode

Not necessarilya single siteaccording to the standards Most current implementations

use a single site

UTRAN

RNC

Node

B

Cell

Cell

Cell

Node

B

Cell

Cell

Cell

IurIu

Uu



Cell

A cell is an area of radio

coverage serviced by one ormore carriers

UTRAN

RNC

Node

B

Cell

Cell

Cell

Node

B

Cell

Cell

Cell

IurIu

Uu



UTRAN Security and privacy

Use of temporary identifier

Encryption for radio channel

Decryption for radio channel

UTRAN

UTRAN



Use of Tempory Identifier

There are a number of different types of equipment anduser identifiers used by UMTS

They have been taken directly from GSM to provide somebackwards compatibility

International Mobile Subscriber Identity (IMSI)

Tempory Mobile Subscriber Identity (TMSI)

Tempory Logical Link Identity (TLLI)

Mobile Station ISDN (MSISDN)

International Mobile Station Equipment Identity (IMEI)

UTRAN

UTRAN



IMSI and TMSI

IMSI is a unique 15 digit

identifier for each user andserves as the primary identifier

It consists of: Mobile Country Code (MCC), 3

digits

Mobile Network Code (MNC),2/3 digits

Mobile Subscriber IdentityNumber (MSIN), 9/10 digits

The TMSI is used to add a level

of security to the SubscriberIdentity

The TMSI is 32 bits long

It may be allocated by either anMSC/VLR or an SGSN

If it is allocated by an SGSN it isknown as a P-TMSI

It is only valid within thenetwork domain that it has beenawarded by and both types maybe simultaneously allocated

MCC MNC MSIN3 bits 2/3 bits 9/10 bits

UTRAN

UTRAN



UTRAN Handover

Radio environment survey

Handover decision

Macro diversity control

Handover control

Handover execution Handover completion

SRNS relocation

Inter-system handover

UTRAN

UTRAN



Handover in UMTS

There are three basic types of handover Intra frequency handovers

Handovers between 2 UMTS carriers at the same frequency

These can be soft handovers

Inter frequency handovers

Handovers between 2 UMTS carriers at different frequencies These are hard handovers

Inter system handovers

Handovers between UMTS and GSM carriers

These are hard handovers

UTRAN

UTRAN



Handover Sets in UMTS

Active Set Cells forming a soft handover connection to the mobile

Candidate Set Cells not presently used in soft handover but who qualify for soft

handover

Neighbour Set Those cells which are continuously monitored but do not yet

qualify for the Candidate Set

UTRAN


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UTRAN


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Macrodiversity between Cells on theSame Node B

If an active set consists of two

connections to cells parentedto the same Node B then thecombining of the two channelsoccurs at the Node B

This is known as a softerhandover

This has no transmissionimplication if cells arecollocated.

RNC

Node

B

Cell

Cell

Cell

Node

B

Cell

Cell

Cell

Iur

Iu

Uu

UTRAN

UTRAN


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Macrodiversity between Node Bs

If an active set consists of

two connections to cellsparented to different NodeBs then the combining ofthe two channels occurs atthe RNC

This is known as a sof thandover

This doubles thetransmission cost of thecall

RNC

Node

B

Cell

Cell

Cell

Node

B

Cell

Cell

Cell

Iur

Iu

Uu

UTRAN

UTRAN


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Macrodiversity between RNSs

RNC

NodeBNodeB

Iu

Uu

RNC

NodeBNodeB

Iur

Iu

Serving RNS Drift RNS

UTRAN

UTRAN


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Macrodiversity between RNSs

SRNS provides link between the Core Network and theUE

SRNS also provides the selection function for the differentchannels

DRNS relays frames to SRNS through Iur

As the UE moves then some diversity paths may bedropped and others established

When the DRNS has more paths than the SRNS the twocan exchange function

Reduces traffic on Iur

UTRAN

UTRAN


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UTRAN

Site Selection Diversity Transmit PowerControl

Site selection diversity transmit power control (SSDT) is

an optional macro diversity method in soft handovermode.

The UE selects one of the cells from its active set to beprimary, all other cells are classed as non primary.

The main objective is to only transmit data on the downlinkfrom the primary cell Reducing the interference caused by multiple transmissions in a

soft handover mode.

A second objective is to achieve fast site selection withoutnetwork intervention

Maintaining the advantage of the soft handover.

UTRAN


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UTRAN

SSDT

Each cell is assigned a

temporary identification (ID) andUE periodically informs theprimary cell ID to the connectingcells.

The non-primary cells selectedby UE switch off thetransmission power for thedownlink data.

The primary cell ID is deliveredby UE to the active cells viauplink FBI field

The cell with the highest CPICHRSCP is the primary cell.

Primary CellNon-Primary Cell

Non-Primary Cell

UE

Control

Data

UTRAN


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Hierarchical Cell structuresUTRAN

Cell Layers in UMTS work on a per carrier basis

Microcell/Macrocell Scenario Hotspot ScenarioFrequency 1 Frequency 2 Frequencies 1 & 2

UTRAN


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Hierarchical Cell Structures

Typically operators will be

awarded 2 or 3 carriers If they are awarded 3 carriers it

is then possible to implementHCS by

Using 2 paired carriers for the

macrocell layer Using 1 paired carrier for the

microcell layer

Using any unpaired spectrumallocated for the picocell layerusing TDD mode

Macro

Micro

Picro

FDD

FDD

TDD

Carrier 1

Carrier 2Carrier 3

Carrier 4

UTRAN

UTRAN


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Inter Frequency Measurements at theUE

GSM: Discontinuous transmission

Room for measurements required for Mobile Assisted Hand Off

Downlink

TX TXUplink

Idle time for measurements

Downlink

Uplink

UTRAN

RXRX

TX TX TX TX TX TX TX TX TX TX TX TX TX TX

RX RX RX RX RX RX RX RX RXRXRX RX RX RX

UMTS FDD: Continuous transmission No idle time for measurements required for MAHO

UTRAN


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Compressed Mode In Compressed Mode a Transmission Gap is created

This allows inter-frequency and inter-systemmeasurements

Probably only required for inter-frequency handover andinter-mode handover to GSM1800

GSM900 dual mode terminals will probably have separatereceivers

UTRAN

Spanningtwo frames

Spanning asingleframe

One Frame,10ms

UTRAN


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Compressed Mode The Transmission Gap is

created by not transmitting for a

number of slots Other slots in the frame

impacted are then forced totransmit at a higher bit rate, alower spreading factor and a

higher power to maintain theuser bit rate

It is possible to have gaps of 3,4, 7, 10 and 14 slots

It is only possible to have gapsof 10 or 14 slots by using twoframes

UTRAN

12 13 14 0 1 2 3 4 510 11 12 13 14 0 1 2 3 4 5 6 7

4 slot gap

UTRAN


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Radio Environment Survey

Received Signal Code Power The received code power of the pilot

Received Signal Strength Indicator The total in-band signal strength of the carrier

E

c/I

ocan be derived from these two items

UTRAN


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UTRAN System Access Control

Admission control

Congestion control

System information broadcasting

UTRAN


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Admission Control

If loading is allowed to increase excessively then the

coverage area of the cell reduces below that planned -Admission Control aims to avoid this

Admission Control functionality is located at the RNC totake the impact on multiple cells into account

The Admission Control algorithm estimates the impact ofadding an additional bearer on both uplink and downlink Only if both pass is the call admitted

There are two broad categories of algorithm

Wideband Power Based Admission Control algorithms Throughput based Admission Control algorithms

UTRAN


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Wideband Power Based AdmissionControl

Uplink Algorithm:

Downlink Algorithm:

Itotal_old+DItotal> Ithreshold

Ptotal_old+DPtotal> Pthreshold

Interference

load

Max Planned Noise Rise

Itotal_old

Ithreshold

DItotal

DL

UTRAN


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Throughput Based Admission Control

Uplink Algorithm

Downlink Algorithm

hUL+DL> hUL_threshold

hDL+DL> hDL_threshold

UTRAN


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Congestion (Load) Control Admission control should ensure that the system is not

overloaded

If it is then congestion control returns the system back tothe targeted load

Possible actions include Downlink fast load control (deny downlink power up commands)

Uplink fast load control (reduce uplink Eb/Notarget)

Reduce packet data traffic throughput

Handover to another WCDMA carrier

Handover to GSM

Decrease bit rates for real time users (e.g. AMR bit rates)

Drop calls in a controlled fashion

UTRAN


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UTRAN Radio Resource Management

Radio bearer set up and release

Reservation and release of physical radio channels

Allocation and release of physical radio channels

Allocation of downlink channelisation codes

Packet data transfer over radio function Radio channel coding and control

Initial access detection and call handling

Power control

UTRAN


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Packet Data Transfer

Packet Access is controlled in UMTS by a Packet

Scheduler (PS) The tasks of the PS are to:

Divide the available air interface capacity between packet users

Decide which transport channels to use for each users packet data

Monitor the packet allocations and the system load

The PS is typically located at the RNC

UTRAN


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Common Transport channels for packetdata

The Common Transport channels

that can be used for packet accessare:

RACH

FACH

Low setup time

Link level performance worse thanthat of dedicated channels due tolack of closed loop power controland soft handover

Most Suitable for small individualpackets

SMS Text only email

Web Page request

Bitrate

Time

User1

User2

User3

User4

User5

User6

User7

Time based packetscheduling is the mechanismemployed when using the

common and sharedchannels

D di t d T t h l fUTRAN


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Dedicated Transport channels forpacket data

Slow setup time

Link level performance betterthan that of common channelsdue to fast closed loop powercontrol and ability to use softhandover

Most Suitable for medium orlarge amounts of data

Bitrate

Time

Code/Transmit based packetscheduling is the mechanism

employed when using thededicated channels

User 1

User 5

User 3

User 4

User 2

UTRAN


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Shared Transport channels for packetdata

The shared Transport channels that can be used for

packet access are DSCH

CPCH

Targetted at bursty packet data

Share a code amongst many users

Can use fast power control

Cannot use soft handover

Suitable for medium amounts of data

UTRAN


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Packet scheduling in UMTS

In reality the packet scheduler

users a combination of time andcode based packet scheduling

The packet scheduler will workwith the admission controlalgorithm to achieve the targetload at a cell

Bitrate

User A

User E

User C

User D

User B

User1

User2

User3

User4

User5

User6

User7

TimeLoad

Target Load

Non Controllable Real TimeLoad

FreeCapacity

D li k M lti l i d Ch lUTRAN


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Downlink Multiplexing and ChannelCoding Chain

CRC Attachment

Transport BlockConcatenation/ CodeBlock Segmentation

Channel Coding

Rate Matching

Insertion of DTXIndication (fixedPositions only)

First Interleaving(20, 40 or 80ms)

Radio FrameSegmentation

OtherTransportChannels Transport

ChannelMultiplexing

Insertion of DTX

indication (WithFlexible Positions only)

PhysicalChannel

Segmentation

SecondInterleaving

(10ms)

PhysicalChannelMapping

DPDCH#1

DPDCH#2

DPDCH#n

U li k M lti l i d Ch l C diUTRAN


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Uplink Multiplexing and Channel CodingChain

CRC Attachment

Transport BlockConcatenation/ CodeBlock Segmentation

Channel Coding

Radio FrameEqualisation

Rate Matching

First Interleaving(20, 40 or 80ms)

Radio FrameSegmentation

OtherTransportChannels Transport

ChannelMultiplexing

PhysicalChannel

Segmentation

SecondInterleaving

(10ms)

PhysicalChannelMapping

DPDCH#1

DPDCH#2

DPDCH#n

UTRAN


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CRC Attachment

The Cyclic Redundancy Check is used to detect errors in

the transport blocks at the receiving end There are five lengths of CRC that can be inserted

0, 8, 12, 16 and 24 bits

The more bits the CRC contains the lower the probabilityof undetected error

C d Bl kUTRAN


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Code BlockConcatenation/Segmentation

The received transport block is either concatenated to

other transport blocks or segmented to allow it to fit into anappropriate block size for the channel coding schemechosen

It is typically better to concatenate as:

It reduces the encoder tail bits overhead It can improve the performance of channel coding to have larger

block sizes

However over a certain limit segmentation is required tolimit complexity

UTRAN


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Channel Coding

In UTRA two channel coding method are used 1/2 and 1/3 rate convolutional coding

1/3 turbo coding

8 state Parallel Concatenated Convolutional Code

UTRAN


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Interleaving

Two different levels of interleaving are used: Inter Frame interleaving

When the delay budget allows more than 10ms of interleaving

It is possible to have interleaving over 20, 40 and 80ms timeperiods

Intra Frame Interleaving

Over a 10ms time period

DTX Indication for Fixed and FlexibleUTRAN


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DTX Indication for Fixed and FlexiblePositions

The use of fixed positions

means that a given transportchannel always occupies thesame positions whenmultiplexed with others

If there is no data DTXindication symbols are inserted

The use of flexible positionsmeans that bits unused by oneservice can be used by another

TFCI TrCH A TPC TrCH B Pilot

TFCI A TPC TrCH B PilotDTX

TFCI TrCH A TPC B PilotA

TFCI TPC TrCH B PilotA B DTX

Fixed Positions: Aand B Full Rate

Fixed Positions: BFull Rate and A 1/3

Rate

Flexible PositionsPositions: A Full

Rate and B 1/3 Rate

Fixed Positions: A1/3 Rate and B 2/3

Rate

UTRAN


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Downlink Transmit Diversity

Transmit DiversityMethod Description

TSTD Time Switched Transmit antennaDiversity (open loop)

STTD Space Time block coding Transmitantenna Diversity (open loop)

Closed Loop Mode 1 Different Orthogonal PilotsClosed Loop Mode 2 Same Pilot

UMTS explicitly allow the use of transmit diversity from the base

station However it is not possible to simply transmit simultaneously form two

close antennas as this would cause an interference pattern - thefollowing methods negate this issue

Channels Using Downlink TransmitUTRAN


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Channels Using Downlink TransmitDiversity

Physical channeltype

Open loop mode

TSTD STTD

ClosedloopMode

P-CCPCH X

SCH X

S-CCPCH X

DPCH X X

PICH X

PDSCH X X

AICH

X

CSICH X

Time Switched Transmit antenna

UTRAN


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Time Switched Transmit antennaDiversity (TSTD)

Even numbered slots transmitted on Antenna 1, odd numbered slots on Antenna 2

Antenna 1

Antenna 2

P-SCH

Slot #0 Slot #1 Slot #14Slot #2

P-SCH

P-SCH P-SCH

S-SCH

S-SCH

S-SCH S-SCH

Space Time block coding TransmitUTRAN


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b0 b1 b2 b3

b0 b1 b2 b3

-b2 b3 b0 -b1

Antenna 1

Antenna 2

Channel bits

STTD encoded channel bits

for antenna 1 and antenna 2.

Space Time block coding Transmitantenna Diversity (STTD)

STTD encoding is optional in UTRAN. STTD support is mandatory at

the UE Channel coding, rate matching and interleaving is done as in the non-

diversity mode.

STTD encoding is applied on blocks of 4 consecutive channel bits

The bit biis real valued {0} for DTX bits and {1, -1} for all otherchannel bits.

Cl d L M dUTRAN


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Closed Loop Mode

Channel coding, interleaving and spreading are done as in

non-diversity mode The spread complex valued signal is fed to both TX

antenna branches, and weighted with antenna specificweight factors w1 and w2

The weight factors are complex valued signals in general. The weight factors are determined by the UE, and

signalled using the D-bits of the FBI field of uplinkDPCCH.

Cl d L M dUTRAN


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Closed Loop Mode

Spread/scramble

w1

w2

DPCHDPCCH

DPDCH

Rx

Rx

CPICH1

Tx

CPICH2

Ant1

Ant2

Tx

Weight Generation

w1 w2

Determine FBI message

from Uplink DPCCH

C ll S h d S h i tiUTRAN


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Cell Search and Synchronisation

In UMTS base stations are not tightly synchronised (s-level) to a

common reference, e.g. GPS Makes for easier deployment, e.g. in indoor environments

All cells transmit different scrambling codes plus commonsynchronisation code

UE searches for primary synchronisation code with matched filter

Synchronises to new cell and acquires time slot clock

UE decodes secondary synchronisation code

Identification of new cell

Radio frame synchronisation

Can now find cells scrambling code from the CPICH to decode thePrimary CCPCH

P C t lUTRAN


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Power Control

Two Levels of Power Control Outer Loop

The RNC sets the target Eb/Nobased upon the BER of the receiveddata

Inner loop

Open loop based upon estimating the path loss from the pilot

Fast closed loop Power control on both the uplink and the downlink

Based upon TPC bits

2 algorithms

Every received bit causes an adjustment in transmit power, either up ordown

A set of commands is sent starting with a sequence of 4 0s. Only if all 5command the bits indicate up is the power increased, all the bits down isthe power decreased. Otherwise power remains the same

P C t l i S ft H dUTRAN


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Power Control in Soft Handover

In Soft Handover multiple power control measurements

might be received In this case a simple rule is used

If any command says power down, then power down

If all commands say power up, then power up

Q tiUTRAN


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Questions

What is the difference between load control and

congestion control? How does handover for UMTS differ from that in

cdmaOne?

If we are continuously receiving data, how do we take

measurements for MAHO?

S i SUTRAN


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Session Summary

In this session we have discussed the major elements and

procedures for UTRAN In the next session we are going to look at the Core

Network

L t SlidUMTS Core Network


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Locator Slide




CDMA Mobile Technology

Overview UMTS Architecture Overview

UMTS Air Interface

Day 1 Roundup


UTRAN UMTS Core Netwo rk


UMTS Mobiles

UMTS Services Course Roundup

UMTS Core Network


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UMTS Core Network

ContentsUMTS Core Network


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Contents

Core Network Overview

Entities Shared between the Circuit Switched Domain andthe Packet Switched Domain

Entities in the Circuit Switched Domain

Entities in the Packet Switched Domain

Contents and Session AimsUMTS Core Network


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Contents and Session Aims

This session aims to go intomore detail about the entities inthe Core Network

It contains:A revisit of the core network

overview

Entities in the different corenetwork domains

Areas in UMTS

The CS and PS

Domains

Shared EntitiesEntities in the CSDomain

Entities in the PSDomain

UMTS System Areas

Core Network (CN)UMTS Core Network


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Core Network (CN)

The Core Network consists of:A Circuit Switched Domain

A Packet Switched Domain

Some CN entities may belong to both domains

CS Entities PS EntitiesCommonEntities

General Core Network ArchitectureUMTS Core Network


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General Core Network Architecture

IUCN

MSC/VLR

SGSN GGSN

GMSC

HLR

ServingGSN

GatewayGSN

GatewayMSC

MobileSwitching

Centre

HomeLocationRegister

Other SGSN

Other MSC

UTRAN

UTRAN

ExternalCircuit

Switched

Networks

External

Packet

Switched

Networks

Iu-cs

Iu-ps

Gs

Gn

Gn

Gr Gc

DD

Gi

FF

AuthenticationCentre

AuC

EquipmentIdentity

RegisterEIR

CS Entities

Common Entities

PS Entities

Why Separate CS domains and PSUMTS Core Network


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Why Separate CS domains and PSdomains?

Advantages of separation

Simple evolution fromGSM/GPRS

Low Risk

Early Availability

Service Continuity

Disadvantages of separation

Build and manage 2 networks Separate engineering and

dimensioning

Greater Infrastructure Cost

Duplicated Functions

MM in VLR and SGSN

Shared Entities in the Core NetworkUMTS Core Network


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Shared Entities in the Core Network

All other entities are shared between the CS and PS

domains Home Location Register

Authentication Centre

Equipment Identity Register

SMS-Service Centre

Home Location RegisterUMTS Core Network


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Home Location Register

A data base in charge of the management of mobile

subscribers. A PLMN may contain one or several HLRs: it depends on

the number of mobile subscribers, on the capacity of theequipment and on the organisation of the network

Contains: Subscription information;

Location information enabling the charging and routing of callstowards the MSC where the MS is registered

Equipment Identity RegisterUMTS Core Network


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Equipment Identity Register

The Equipment Identity Register (EIR) is the logical entity

which is responsible for storing in the network theInternational Mobile Equipment Identities (IMEIs)

The equipment is classified as "white listed", "grey listed","black listed" or it may be unknown

The white listis composed of all number series of equipmentidentities that are permitted for use

The black listcontains all equipment identities that belong toequipment that need to be barred

Equipment on the grey listare not barred, but are tracked by thenetwork (for evaluation or other purposes)

Authentication CentreUMTS Core Network


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Authentication Centre

The Authentication Centre (AuC) is associated with an

HLR, and stores an identity key for each mobile subscriberregistered with the associated HLR. This key is used togenerate:

data which are used to authenticate the International MobileSubscriber Identity (IMSI);

a key used to cipher communication over the radio path betweenthe mobile station and the network.

SMS Service CentreUMTS Core Network


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SMS Service Centre

The SMS-SC deals with the transfer of short of short text

messages This works on a store and forward basis

Circuit Switched DomainUMTS Core Network


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Circuit Switched Domain

The CS domain deals with circuit switched type

connections and the associated signalling i.e. those connections that require a dedicated resource

Entities specific to the CS domain are: MSC

GMSC VLR

Mobile Switching CentreUMTS Core Network


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Mobile Switching Centre

The Mobile-services Switching Centre (MSC) constitutes

the interface between the radio system and the fixednetworks.

The MSC performs all necessary functions in order tohandle the circuit switched services to and from the mobilestations

UMTS MSCs can be expected to be identical in hardwareto latest generation GSM MSCs, although with a differentsoftware version

Gateway MSCUMTS Core Network


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Gateway MSC

If a network delivering a call to the PLMN cannot

interrogate the HLR, the call is routed to an MSC. This MSC will interrogate the appropriate HLR and then

route the call to the MSC where the mobile station islocated.

The MSC which performs the routing function to the actuallocation of the MS is called the Gateway MSC (GMSC).

Visitor Location RegisterUMTS Core Network


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Visitor Location Register A mobile station roaming in an MSC area is controlled by

the Visitor Location Register in charge of this area.

When a Mobile Station (MS) enters a new location area itstarts a registration procedure.

The MSC in charge of that area notices this registration

and transfers to the Visitor Location Register the identityof the location area where the MS is situated.

If this MS is no yet registered, the VLR and the HLRexchange information to allow the proper handling of calls

involving the MS. A VLR may be in charge of one or several MSC areas.

Packet Switched DomainUMTS Core Network


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Packet Switched Domain

The PS domain deals with packet switched type

connections and associated signalling i.e. those that are comprised of concatenations of bits formed into

packets, each of which can be routed independantly

Entities specific to the PS domain are:

SGSN GGSN

Serving GPRS Support NodeUMTS Core Network


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Serving GPRS Support Node Essentially a router supporting packet data transfer within

UMTS

For packet switched data performs additionally the role ofthe VLR and contains: Subscription information:

The IMSI;

One or more temporary identities;

Zero or more PDP addresses.

Location information:

Depending on the operating mode of the MS, the cell or the routeing areawhere the MS is registered;

The VLR number of the associated VLR (if the Gs interface is

implemented);

The GGSN address of each GGSN for which an active PDP context exists

Gateway GPRS Support NodeUMTS Core Network


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Gateway GPRS Support Node

Acts as a gateway into the packet switched network much

as the GMSC subscription information:

the IMSI;

zero or more PDP addresses.

location information:

the SGSN address for the SGSN where the MS is registered.

UMTS System AreasUMTS Core Network


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UMTS System Areas Location Area

UEs registered on the CS domain report their position in terms of LA

UEs in idle mode monitor Location Area Identities (LAIs) and report changes

Stored in the VLR

Routing Area UEs registered on the PS domain report their position in terms of RA

UEs in both idle and connected mode monitor Routing Area Identities (RAIs) andsupport changes

Stored in the SGSN

UTRAN Registration Area Used once a signaling/traffic connection is established

A subset of a RA

Only relevant to PS mode of operation

Used by the RNC (not really relevant to the CN)

QuestionsUMTS Core Network


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Questions

What are the advantages and disadvantages of having

separate CS and PS Domains in the core network? Which entities are involved in Mobility Management of

visiting users?

Session SummaryUMTS Core Network


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Session Summary

In this session we have looked at the major UMTS CN

entities in: The CS Domain

The PS Domain

Shared entities

In the next session we shall look at the fixed networkinterfaces in UMTS

Locator SlideUMTS Fixed Network Interfaces


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Locator Slide






UMTS Air Interface

Day 1 Roundup


UTRAN UMTS Core Network

UMTS Fixed NetworkInterfaces

UMTS Mobiles

UMTS Services

Course Roundup



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Contents and Session AimsUMTS Fixed Network Interfaces


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Contents and Session Aims

This session aims to explore theFixed Network Interfaces inUMTS in more detail

A general model for theinterfaces

ATM in UMTS

The Fixed Network Interfaces

General Protocol Model

IP vs ATMATM

IubIurIu

General Protocol Model for UTRANUMTS Fixed Network Interfaces


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Terrestrial Interfaces

DataStream(s)

ApplicationProtocol

Control Plane User PlaneRadioNetwork

Layer

TransportNetwork

Layer

Transport Network

User PlaneTransport Network

User PlaneTransport Network

Control Plane

SignallingBearer(s)

DataBearer(s)

SignallingBearer(s)

ALCAP(s)

Physical Layer

Horizontal Layers in the GeneralUMTS Fixed Network Interfaces


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Protocol Model All UTRAN related issues are only visible in the Radio

Network Layer The Transport Layer simply represents standard transport

technology for use in UTRAN

e.g. ATM and appropriate adaptation layers

Vertical Planes in the General ProtocolUMTS Fixed Network Interfaces


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Model The Control Plane is for all UMTS specific control signalling including:

Application Protocol Signalling Bearer

The User Plane is for all data sent and received by the user including: Data Streams

Data Bearers

Transport Network Control Plane contains all signalling within theTransport Layer

Transport Network User Plane contains the Signalling and DataBearers for the Radio Network Layer Protocols

IP vs. ATMUMTS Fixed Network Interfaces


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One of the major uncertainties over the fixed network

interfaces in UMTS is whether IP or ATM will be used ATM is a mature technology and specified in the release

99 of the 3GPP standards

IP v6 is required, if IP is to be used by UMTS, due to its

QoS improvements

ATMUMTS Fixed Network Interfaces


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ATM is the default transport network layer for a UMTS

network There are two types of ATM interconnections defined

NNI Network-Network Interfaces

Interfaces between two ATM switches

UNI User-Network Interfaces Interfaces between a user terminal and an ATM switch

ATM LayerUMTS Fixed Network Interfaces


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y

ATM provides the data linkconnection across a network

An ATM cell consists of:A five octet header containing:

Virtual Path Identifier

Virtual Channel Identifier

A 48 octet payload

3

2

1

OSI

Data Link Layer

Physical

ATM Layer

ATM AdaptationLayer

Higher LayerProtocols

Physical Layer

ATM Service ClassesUMTS Fixed Network Interfaces


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ATM Adaption Layer Connection

Mode

Bit Rate Example Use

AAL 1 ConnectionBased

Constant Digital voice

AAL 2 ConnectionBased

Variable Variable ratevideo

AAL 3 Connection Variable X.25, FrameRelay

AAL 4 Connectionless Variable TCP/IP, SMDS

AAL 5 Connectionless Variable TCP/IP

UMTS uses:AAL2 to provide a synchronous connection based service

AAL5 to provide an asynchronous connectionless service

Major Interfaces in UMTSUMTS Fixed Network Interfaces


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j

There are four major newinterfaces defined in UMTS

IuThe interface betweenUTRAN and the CN

Iur

The Interface between

different RNCs

Iub

The interface between theNode B and the RNC

Uu

The air interface

RNC

Node-

B

RNC

UE

CN

Uu

Iu

Iub

Iur

IubUMTS Fixed Network Interfaces


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ub The Iubis the interface between the RNC and the Node-B

The Node B effectively performs a relay function betweenthe Iuband the Uu

Thus the Iubneeds to carry: Layer 2+ signalling between the UE and the UTRAN

Signalling directly to the Node B

To control radio resource allocation

General control of the Node-B

O&M Functionality

IubProtocol StackUMTS Fixed Network Interfaces


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NBAPControl Plane User Plane

Radio

NetworkLayer

TransportNetwork

Layer

Transport Network

User Plane

Transport Network

User Plane

AAL2

Physical Layer

ATM

AAL5SSCOP

SSCF-UNI

DCHFP

RACHFP

FACHFP

PCHFP

DSCHFP

ub

In the Iubthe ApplicationProtocol is the Node B

Application Protocol (NBAP) This is carried over the

Signalling ATM AdaptationLayer UNI (SAAL-UNI) whichitself comprises

Service Specific Co-ordinationFunction - UNI (SSCF-UNI)

Service Specific ConnectionOrientated Protocol (SSCOP)

AAL5

A dedicated AAL2 connection isreserved for each User Planeservice

IubRadio Network Layer User PlaneUMTS Fixed Network Interfaces


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ub y

The DCH Frame Protocol (FP) consists of: IubDCH Data Frames

The Iubinterface provides means for transport of uplink anddownlink DCH Iubframes between RNC and Node B.

The DCH Iubframe header includes uplink quality estimates andsynchronisation information

IubDCH Control Frames These are used to carry control information such as power and

timing control

Iub RACH FP, FACH FP, PCH FP and DSCH FP carry theequivalent channels

IubRadio Network Layer Control PlaneUMTS Fixed Network Interfaces


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ub y The Iubinterface allows the RNC and the Node B to negotiate about radio

resources

The protocol used is the Node B Application Part (NBAP)

Main Functions Radio Channel Management

Radio Resource Management

Radio Network Performance Measurement

Cell Configuration Management

Operations and Maintenance

IubLink Management

Example NBAP messages are: measurement request

radio link set-up

cell set-up

cell delete

Implementation of the IubUMTS Fixed Network Interfaces


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ub

Transmission sharing between the GSM/GPRS Abis

interface and the Iubinterface is allowed The functional division between RNC and Node B has as

few options as possible

Neither the physical structure nor any internal protocols of

the Node B are visible over Iuband are thus not limitingfactors, e.g.

When introducing future technology

In multi vendor networks

IurUMTS Fixed Network Interfaces


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u The Iuris the interface between two RNCs

It enables the transport of air interface signalling betweenan SRNC and a DRNC

Thus the Iurneeds to support: Basic Inter RNC Mobility

Dedicated Channel Traffic

Common Channel Traffic

Global Resource Management

Iur Protocol Stack



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RNSAP

Control Plane User PlaneRadio

NetworkLayer

TransportNetwork

Layer

Transport Network

User Plane

Transport Network

User Plane

AAL2

Physical Layer

ATM

AAL5

DCHFP

CCHFP

SSCOP

SSCF-NNI

MTP3-B

IP

SCTP

M3UA

SCCP

In the Iubthe Application Protocol is the RadioNetwork Subsystem Application Protocol(RNSAP)

This is carried over the Broad Band SS7 (BBSS7) protocols comprising Signalling Connection Control Part (SCCP)

Message Transfer Part (MTP3-b)

Service Specific Co-ordination Function - NNI(SSCF-NNI)

SSCOP

AAL5

An alternative IP based signalling protocol canbe used comprising

SS7 MTP3 User Adaptation Layer (M3UA)

Simple Control Transmission Protocol (SCTP)

Internet Protocol (IP)

A dedicated AAL2 connection is reserved for

each User Plane service

IurRadio Network Layer User PlaneUMTS Fixed Network Interfaces


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The DCH Frame Protocol (FP) consists of: IurDCH Data Frames

The Iurinterface provides means for transport of uplink anddownlink DCH Iurframes between RNCs.

The DCH Iurframe header includes uplink quality estimates andsynchronisation information

Sometimes called Iur/IubDCH Data Frames as they are the same as

on the Iub IubDCH Control Frames

These are used to carry control information such as power andtiming control

Sometimes called Iur/IubDCH Control Frames as they are the same

as on the Iub

Similarly for CCH FP


IurRadio Network Layer Control Plane


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The Iur interface allows the RNCs to communicate regarding the The protocol used is the Radio Network Subsystem Application Part (RNSAP)

Split into 4 parts Iur1: Basic Inter-RNC Mobility

SRNC Relocation

Inter RNC cell and URA Update

Inter RNC Packet Paging

Reporting of Protocol Errors

Iur2: Dedicated Channel Traffic

Support of DCH transfer across the Iur

Iur3: Common Channel Traffic

Transport of CCH transfer across the Iur

Iur4: Global Resource Management

Transfer of Cell Measurements

Transfer of Node B Timing Information

Implementation of the IurUMTS Fixed Network Interfaces


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Some Vendors are suggesting collocated RNCs to rmove

the necessity for high data rate Iurs

IuUMTS Fixed Network Interfaces


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The Iuis the interface between the Core Network and theUTRAN

There are two instances of the Iu: The Iu-ps connecting UTRAN to the Packet Switched Network

The Iu-csconnecting UTRAN to the Circuit Switched Network

Iu-ps Protocol Stack

I th I th A li ti P t l i th



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RANAP


Network

Layer

TransportNetwork

Layer

Transport Network

User Plane

Transport Network

User Plane

AAL2

Physical Layer

ATM

AAL5

SSCOP

SSCF-NNI

MTP3-B

IP

SCTP

M3UA

SCCP

IuUser Planeprotocol

IP

UDP

GTP-U

In the Iu-psthe Application Protocol is theRadio Access Network Application Protocol(RANAP)

This is carried over the Broad Band SS7 (BB

SS7) protocols comprising SCCP

MTP3-b

SSCF-NNI

SSCOP

AAL5

An alternative IP based signalling protocol canbe used comprising

M3UA

SCTP

IP

A User Plane Protocols are carried over GPRS Tunneling Protocol - User Plane (GTP-U)

User Datagram Protocol (UDP)

IP

AAL2

Iu-cs Protocol Stack



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RANAP


NetworkLayer

TransportNetwork

Layer

Transport Network

User Plane

Transport Network

User Plane

AAL2

Physical Layer

ATM

AAL5

SCCP

IuUser Planeprotocol

MTP3b

SSCF-NNI

SSCOP

In the Iu-csthe ApplicationProtocol is the RANAP

This is carried over the BB SS7protocols comprising

SCCP

MTP3-b

SSCF-NNI

SSCOP

AAL5

A User Plane Protocols arecarried over AAL2

RANAP Protocol The RANAP functions are:



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The RANAP functions are: SRNS Relocation and Hard Handover

Radio Access Bearer Management

Reporting Unsuccessfully Transmitted Data

Common ID Management

Paging

Management of Tracing

UE-CN signalling transfer

Security mode control

Management of Tracing

UE-CN Signalling Transfer

Security Mode Control

Management of Overload over the Iuinterface

Reset of the Iuinterface

Location Reporting

QuestionsUMTS Fixed Network Interfaces


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What functions does the Iurhave other than transporting

data and control channels to the SRNS? What are the two horizontal layers of the General Protocol

Model and how do they differ?

Which ATM Adaptation Layers are used in UMTS and

what are their properites?

Session SummaryUMTS Fixed Network Interfaces


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In this session we have looked at the major UMTS

interfaces Iu

Iub

Iur

We have also seen how these interfaces are split into ageneral model and how this applies to specific instances

Locator SlideUMTS Mobiles


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UMTS Air Interface

Day 1 Roundup


UTRAN UMTS Core Network


UMTS Mobiles

UMTS Services Course Roundup

UMTS Mobiles


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UMTS Mobiles

Contents and Session AimsUMTS Mobiles


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UE Service StatesIdle Mode Processes

This session aims to explore thefunctionality of the UE and the

processes that it directs UE States and Idle Mode

Processes

UE measurements

Mobile Trends

UE MeasurementsUTRAN Measurements

Phones of the FutureMobile Trends

UE Power Classes and ModesUMTS Mobiles


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Power Class Maximum output power

TDD

Maximum output power

FDD

1 [+33] dBm +33 dBm

2 [+27] dBm +27 dBm

3 [+24] dBm +24 dBm

4 [+21] dBm +21 dBm

5 [+10] dBm

6 [ 0 ] dBm

User Equipment Service StatesUMTS Mobiles


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Detached

CS-Connected PS-Connected

Idle

The UE operates in one of threebasic states

Detached

Not registered to the network

Idle

Registered to the network andperforming both LA and RA updates

Connected

CS-Connected

Does not perform LA updates

CS Signalling/Traffic LinkEstablished

PS-Connected

PS Signalling/Traffic LinkEstablished

RA updates for boundarycrossings

Idle ModeUMTS Mobiles


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Idle mode is when the UE has: Selected a PLMN

Selected a cell

Carried out Location Registration

Once in Idle mode the UE continually reassess its serving cell Monitoring the serving cells and neighbouring cells radio performance

The UE should be served by the most reliable cell

Monitoring signalling information

P-CCPCH for cell and system parameters which could provoke cellreselection

S-CCPCH for paging or notification resulting in connection establishment

SynchronisationUMTS Mobiles


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In order to select a PLMN or cell the UE must first be

synchronised to the network As we discussed earlier the procedure for this is:

Derive timing from P-SCH

Derive scrambling code group from S-SCH

Derive scrambling code from CPICH Once the UE has this information it can then decode the

P-CCPCH since it already knows it s rate andchannelisation code which are fixed

Cell SelectionUMTS Mobiles


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There are two possibilities for cell selection procedures:

Initial Cell Selection The UE has no knowledge of which radio channels th ePLMN is

using.

The UE scans all channels within the UMTS band

Once a carrier belonging to the required PLMN is found the UE will

begin cell selection Stored Information Cell Selection

The UE has previously stored information on the carrier frequenciesof the required PLMN

Cell Selection CriteriaUMTS Mobiles


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Cell Selection is based upon S where

S = Qmeas- Qmin - Pcompensation Q meas is the Signal to Interference Ratio for the candidate cell

Qminis the minimum required SIR

Pcompensation is a correction value for different power classes ofmobile

If S>0 then the cell is a valid candidate

The UE will camp on the cell with the highest S

Cell ReselectionUMTS Mobiles


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The causes for cell reselection are:

A better cell has been found S has fallen below 0

Communication with the serving cell has failed

The serving cell has become barred or forbidden

Cell Reselection Criteria Cell Reselection is based upon R where:

UMTS Mobiles


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Cell Reselection is based upon R where:

Rs= Qmaps+ Qhysts

Rn= Qmapn- Qoffset- TOn.(1-Ln) Rsis the rank for the serving cell

Rnis the rank for a neighbouring cell

Qmapsis the quality measurement from the serving cell

Qmapnis the quality measurement from a neighbouring cell

Qhysts

and Qoffset

are broadcast by the serving cell and used to control thetraffic distribution in the system

TOn is a tempory offset present until a timer expiry to prevent short termreselection

Lndetermines whether TOnis used

The cell with the highest ranking is selcted

If this is a neighbour cell this is only occurs if this status is maintainedfor a period in time

Immediate Cell EvaluationUMTS Mobiles


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Just prior to a RACH the UE will perform a search to

ensure that it is using the correct cell Cell reselection occurs if Sn> 0

Qmapn > Qmaps+ Qoffset

Measurements at the UE UTRA carrier RSSI

UMTS Mobiles


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UTRA carrier RSSI Received Signal Strength Indicator, wideband received power within the channel

bandwidth

CPICH RSCP CPICH Received Signal Code Power, received power on CPICH after despreading

CPICH Ec/No

CPICH Energy/chip to Noise power spectral density,

(CPICH Ec/Io) = (CPICH RSCP) / RSSI

CPICH ISCP CPICH Interference on Signal Code Power, interference on received signal after

despreading

CPICH SIR

CPICH Signal to Interference Ratio, (CPICH SIR) = (CPICH RSCP) / (CPICH ISCP)

Measurements at the UEUMTS Mobiles


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SIR

Signal to Interference Ratio, SIR = (DPCCH RSCP) / (DPCCH ISCP)

Transport channel BLER Estimation of transport channel block error rate

UE transmitted power Total transmitted power of the UE measured at the antenna

connector/indication of TX power reaching threshold

Measurements at the UTRANUMTS Mobiles


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Transport channel BLER

Estimation of transport channel block error rate Physical channel BER

Physical channel BER measured on control part after RLcombining

Transport channel BER Transport channel BER measured on data part after RL combining

Measurements at the UTRANUMTS Mobiles


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RSSI

Received Signal Strength Indicator, the wideband received powerwithin the UL channel

Transmitted carrier power The transmitter carrier power is the ratio between the total

transmitted power on one DL carrier and the maximum power to

use on that carrier

Transmitted code power The transmitted power on one carrier, scrambling and

channelisation code combination

Some UMTS OptionsUMTS Mobiles


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3GCore

Phone

InformationManager

PC Card

Voice + low data

384 kbits/s data

2 Mbits/s data

Phone of the Future: DoCoMoUMTS Mobiles


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Phone of the Future: EricssonUMTS Mobiles


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Phone of the future: PanasonicUMTS Mobiles


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Phone of Today: NokiaUMTS Mobiles


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Phone of Today: UbineticsUMTS Mobiles


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Handheld Products: Small Runs...UMTS Mobiles


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1998 figures:

3 m total PDA sales (US) 62 models in the marketplace!

Average product lifetime ~1 year

A successful GSM phone model might sell 10 m Quite a difference in volume

Which will model UMTS follow???

PA Technology PredictionsUMTS Mobiles


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Vast range of products by 2005, changing fast

Some will be palmtops, most will not Diverse range of services, using GSM, GPRS, UMTS, fixed line or

a combination

UMTS needs to accommodate the take up of services which arestarting now over 2G and 2.5G technologies

Most of the UK may never have UMTS coverage UMTS is just another modem

Should be product independent

Must be cheap for consumer products

GSM/GPRS multi-mode is vital

Terminal TypesUMTS Mobiles


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Source: UMTS Forum

Parts Cost: 3G PDA

UMTS Inside becomes a small

UMTS Mobiles


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$ 0.00

$ 50.00

$ 100.00

$ 150.00

$ 200.00

$ 250.00

$ 300.00

GSM UTRA UTRA PDA

Sundry

Keypad

LCD screenWinCE license

CPU

8 Mbyte ROM

8 Mbyte RAM

Baseband

RF

UMTS Inside becomes a smallpart of product parts cost,compared with eg

B&W LCD screen (~ $80)

WinCE CPU (eg MIPS, ARM ($5 -15)

Pentium II ($500)

OtherItems

UMTSInside

QuestionsUMTS Mobiles


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What does the UE do before making a random accessattempt?

What are the four UE Service States?

What are the major components of cost for a PDA stylemobile?


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Locator SlideUMTS Services


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UMTS Air Interface

Day 1 Roundup


UTRAN

UMTS Core Network


UMTS Mobiles

UMTS Services

Course Roundup

UMTS Services


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UMTS Services

Contents and Session AimsUMTS Services

UMTS Services and


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Applications In this session we shall look atservices and QoS issues in

UMTS UMTS services

QoS Bearer Architecture andAttributes

Service Classes

Major Service Types

Architecture of a UMTSBearer ServiceUMTS Bearer Attributes

UMTS QoS Classes

Example UMTS

Services

UMTS Services and Applications

Offi I f ti

UMTS Services


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InformationIntelligentSearch and FilteringagentsInternet SurfingOn-line mediaOn-line translationLocal informationBooking & ReservationNews

Office InformationVirtual Working GroupsTele-working

Schedule Synchronisation

Special ServicesSecurity ServiceHotlineTele-medecine

CommunicationsVideo TelephonyVideo ConferencingSpeechEmailAnnouncing ServicesSMSElectronic Postcards

Financial ServicesOn-line bankingUniversal SIM & Credit CardHome ShoppingStock Quotes

TelemetricServicesMachine-MachineServicesLocation Based TrackingNavigation AssistanceTravel InformationFleet ManagementRemote Diagnostics

Public ServicesPublic Elections/VotingPublic InformationHelp

Broadcast ServicesYellow Pages

LeisureVirtual Book StoreMusic on DemandGames on DemandVideo-clipsVirtual Sight Seeing

Lottery Services

EducationVirtual SchoolOn-line Laboratories

On-line LibraryOn-line TrainingRemote Consultation

Architecture of a UMTS bearer serviceUMTS Services


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TE TEUE UTRANCN

edge nodeCN

gateway

End-to-End Service

TE/UE LocalBearer Service UMTS Bearer Service

Radio Access Bearer Service

External BearerService

CN BearerService

Radio BearerService

IuBearerService

Backbone NetworkService

UTRA FDD/TDDService

Physical BearerService

QoS Bearer AttributesUMTS Services


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Maximum bitrate (kbps)

Guaranteed bitrate (kbps)

Delivery order (y/n)

Maximum SDU size (octets)

SDU format information (bits)

SDU error ratio Residual bit error ratio

Delivery of erroneous SDUs(y/n/-)

Transfer delay (ms)

Traffic handling priority

Allocation/Retention Priority

Maximum bitrateUMTS Services


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Maximum bitrate (kbps)

Maximum bitrate can be used to make code reservations in thedownlink of the radio interface

Its purpose is

to limit the delivered bitrate to applications or external networks withsuch limitations

to allow maximum wanted user bitrate to be defined for applicationsable to operate with different rates

Guaranteed bitrate

G d b f bi d li d b UMTS i hi

UMTS Services


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Guaranteed number of bits delivered by UMTS within atime period

Guaranteed bitrate may be used to facilitate admission control based on available resources and

resource allocation within UMTS.

Quality requirements expressed by e.g. delay andreliability attributes only apply to incoming traffic up to theguaranteed bitrate

Delivery order

I di t h th th UMTS b h ll id i

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Indicates whether the UMTS bearer shall provide in-sequence SDU delivery or not.

The attribute is derived from the user protocol (PDP type)and specifies if out-of-sequence SDUs are acceptable ornot.

This information cannot be extracted from the traffic class.

Whether out-of-sequence SDUs are dropped or re-ordered depends on the specified reliability

Maximum SDU size

Th i ll d SDU i

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The maximum allowed SDU size

The maximum SDU size is used for admission control andpolicing.

SDU format information

Li t f ibl t i f SDU

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List of possible exact sizes of SDUs

UTRAN needs SDU size information to be able to operatein transparent RLC protocol mode, which is beneficial tospectral efficiency and delay when RLC re-transmission isnot used.

Thus, if the application can specify SDU sizes, the beareris less expensive

SDU error ratio

I di t th f ti f SDU l t d t t d

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Indicates the fraction of SDUs lost or detected aserroneous.

Note that by reserving resources, SDU error ratioperformance is independent of the loading conditions,whereas without reserved resources, such as inInteractive and Background classes, SDU error ratio is

used as target value. Used to configure the protocols, algorithms and error

detection schemes, primarily within UTRAN.

Residual bit error ratio

I di t th d t t d bit ti i th d li d

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Indicates the undetected bit error ratio in the deliveredSDUs.

If no error detection is requested, Residual bit error ratioindicates the bit error ratio in the delivered SDUs.

Used to configure radio interface protocols, algorithms anderror detection coding

Delivery of erroneous SDUs

I di t h th SDU d t t d h ll b

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Indicates whether SDUs detected as erroneous shall bedelivered or discarded.

Used to decide whether error detection is needed andwhether frames with detected errors shall be forwarded ornot.

Transfer delay

Indicates maximum delay for 95th percentile of the distribution of

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Indicates maximum delay for 95th percentile of the distribution ofdelay for all delivered SDUs during the lifetime of a bearer service

Delay for an SDU is defined as the time from a request to transfer anSDU at one SAP to its delivery at the other SAP.

Used to specify the delay tolerated by the application.

It allows UTRAN to set transport formats and ARQ parameters

Transfer delay of an arbitrary SDU is not meaningful for a burstysource, since the last SDUs of a burst may have long delay due toqueuing, whereas the meaningful response delay perceived by theuser is the delay of the first SDU of the burst.

Traffic handling priority

Specifies the relative importance for handling of all SDUs

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Specifies the relative importance for handling of all SDUsbelonging to the UMTS bearer compared to the SDUs ofother bearers.

Within the interactive class, there is a definite need todifferentiate between bearer qualities.

This is handled by using the traffic handling priorityattribute, to allow UMTS to schedule traffic accordingly.

By definition, priority is an alternative to absoluteguarantees, and thus these two attribute types cannot beused together for a single bearer.]

Allocation/Retention Priority

Specifies the relative importance compared to other

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Specifies the relative importance compared to otherUMTS bearers for allocation and retention of the UMTSbearer. The Allocation/Retention Priority attribute is asubscription parameter which is not negotiated from themobile terminal.

Priority is used for differentiating between bearers when

performing allocation and retention of a bearer. In situations where resources are scarce, the relevant

network elements can use the Allocation/Retention Priorityto prioritise bearers with a high Allocation/RetentionPriority over bearers with a low Allocation/RetentionPriority when performing admission control

Asymmetric Bearers

Uni directional and bi directional bearer services are

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Uni-directional and bi-directional bearer services aresupported.

For bi-directional bearer services, the attributes Maximumbitrate and Guaranteed bitrate can be set separately foruplink/downlink in order to support asymmetric bearers.


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Conversational Class

Preserve time relation between information entities of the

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Preserve time relation between information entities of thestream - transmission and reception in the same order

Conversational pattern - symmetric

Real time - low delay required

Typically between peers

Example Applications: Voice

Videotelephony

Video Games

Streaming

Preserve time relation between information entities of the

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Preserve time relation between information entities of thestream - transmission and reception in the same order

Highly asymmetric

Real time - relatively low delay required

Typically between server and client

Example Applications Web broadcast

Video on demand

Miscellaneous streaming multimedia

Interactive

Request response pattern

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Request response pattern

Preserve data integrity Relatively delay sensitive but not real time

Treated as non-real time packet based

Example applications: Web browsing

Network games

Location based services

Database retrieval

Background

Destination is not expecting the data within a certain time

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Destination is not expecting the data within a certain time

Preserve data integrity Treated as non-real time packet based

Example Applications Download of emails

SMS

Reception of measurement records


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UMTS AMR Speech Codec

Standard codec likely to be the multirate coder developed

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16

U101 UMTS Network Systems Overview

Standard codec likely to be the multirate coder developedfor GSM

provides EFR quality for good channel

provides good quality in poor conditions

The multirate codec has 14 combined channel and codecmodes

codec produces 8 source rates (4.75, 5.15, 5.9, 6.7(PDC-EFR),7.4(IS-641), 7.95, 10.2 and 12.2 kbps(GSM-EFR))

employs variable protection coding according to channel

coding rate between 1/2 and 1/5

puncturing used to match bit rate to channel

Universal Personal Telecommunications

UPT means a user can be contacted wherever they are

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UPT means a user can be contacted wherever they arethrough a single number

User mobility rather than terminal mobility

The number translation capability of IN can be used toroute a call to a convenient and suitably equipped localterminal

A number is associated with a person not a terminal or ID card

Virtual Home Environment

The VHE means that a roaming user can access the

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The VHE means that a roaming user can access theservices that he would have access to on his home

network

Ideally the user should not notice he is not in his homenetwork

Again VHE can be implemented in UMTS through the inclusion of

IN functionality

SIM Application Toolkit

SIM Application Toolkit Features include:

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S pp cat o oo t eatu es c ude

Profile Download

To verify support of the SIM Application Toolkit by both SIM and ME

Data Download

To enable SMS to transfer data directly to an application on the SIM

Proactive SIM

To allow the SIM to operate the call control functions of the ME

Menu Selection

To enable an application on the SIM to create and operate a menu on theME

Call Control by SIM

All dialled digits may be passed to an application on the SIM which may bar,modify or allow the call

Location Based Services In many regions a Location Function is a condition of the

license

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license

Location information may be provided on request from aclient application (in either the UE or CN)

There are three main types of location derivation Cell Identity Based

Giving a position within the cells coverage area

Timing Based

Derived from relative timing measurements made on radiotransmissions

Network Assisted GPS

A UE is equipped with a GPS, whose performance may beimproved by the network

Questions

What are the four UMTS QoS Classes?

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What are the four UMTS QoS Classes?

How might location be determined for location basedservices in UMTS?

What is the maximum and minimum rate of the AMRspeech codec?

Session Summary

In this session we have investigated

UMTS Services


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In this session we have investigated

QoS Architecture in UMTS

Bearer attributes

QoS Classes

Example services such as the AMR

Locator Slide

Introductory Session Day 2 Introductory Session

Course Roundup


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y





UMTS Air Interface

Day 1 Roundup

y y

UTRAN

UMTS Core Network


UMTS Mobiles

UMTS Services

Course Roundup

Course Roundup


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Course Roundup


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UMTS Network Systems Overview Day 2

Documents

Transcript of UMTS Network Systems Overview Day 2