UMTS Introduction & Wcdma HSDPA Fundmental JP

7/27/2019 UMTS Introduction & Wcdma HSDPA Fundmental JP

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For internal use only

2 Nokia Siemens Networks UMTS Introduction & WCDMA/HSDPA Fundamentals / 16th April 2010 / JP

Some Terminology

IMT-2000

International Mobile Telecommunication system

ITU name for 3rd generation mobile communication

There will be several IMT-2000 systems (WCDMA, EDGE, cdma2000,...)

UMTS

Universal Mobile Telecommunication System

ETSI name for 3rd generation mobile communication

UTRA UMTS Terrestrial Radio Access

UTRA is the radio-access part of UMTS

WCDMA

WCDMA = Wideband Code Division Multiple Access

WCDMA (Wideband DS-CDMA) is the radio access technology used forUTRA


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Cellular Evolution


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1st and 2nd Generation Systems

Analogue systems (e.g TACS, NMT, AMPS) are firstgeneration systems

First commercial services, giving voice capability

Digital systems gradually replaced these during 1990s

GSM 900/1800/1900

PDC cdmaOne (IS-95)

US-TDMA (IS-136)

Enhancements made to existing 2nd generation systemsare sometimes called 2.5G. Examples are:

GPRS and EDGE in GSM

PDC-Packet in PDC


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Why 3rd Generation?

Second generation systems are fundamentally limited

in their expandability by the underlying technologiesinvolved

Purpose of 3rd generation is to allow flexible, high bit-rate communications to be performed, allowing a

variety of new multi-media applications to bedeveloped

Target is also to have much greater convergence ofstandards worldwide than existing second generationsystems


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3rd Generation Requirements

Bit rates up to 10Mbps (384kbps is max with R99 and 10Mbps with HSDPA)

Variable bit rate to offer bandwidth on demand

Multiplexing services with different QoS on single connection

Satisfy differing delay requirements from real-time (voice) tobest-effort packet (data) services

Co-existence with 2nd generation systems

Support asymmetric up/down link traffic (e.g. web browsinghas much more downlink than uplink traffic)

High spectrum efficiency: use scarce resource in most

efficient manner


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3rd Generation in Europe

Basic research into different access technologies was startedin earnest in the early 1990s

By 1997, five basic technologies had been identified by ETSIas possible candidates for 3rd generation air interface

Wideband CDMA (WCDMA)

Wideband TDMA (WTDMA)

Wideband TDMA/CDMA (WTDMA/CDMA)

OFDMA

ODMA

Decision was taken in Jan 98: WCDMA for paired spectrum bands (I.e. uplink and downlink on

separate frequencies offset from each other, Frequency Division DuplexFDD)

WTDMA/CDMA for unpaired spectrum bands (I.e. uplink and downlinkon same frequencies, but separated in time, Time Division Duplex TDD)


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3rd Generation in Japan

DoCoMo have been doing basic research on WCDMA formany years, in conjunction with their Mova suppliers

Experimental system was developed during 1996-1998 toprove basic technology

Nokia were part of Mova family for this development JuDI project in Oulu developed proto systems, which were tested in

Japan ARIB (the Association for Radio Industries and Businesses)

selected WCDMA as the chosen solution for Japan in 1997


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3rd Generation in US/Korea

US government adopts a "technology neutral" approach,which has resulted in multitude of standards. Ones withmost support were:

WCDMA N/A (North America) in T1P1 (Technical committee -similar to ARIB/ETSI WCDMA)

UWC-136 (narrow and wide band TDMA)

cdma2000 (wideband version of IS95)Telecomms Technology Assoc (TTA) adopted two trackapproach in Korea

Synchronous WCDMA (similar to ARIB/ETSI WCDMA)

Asynchronous WCDMA (similar to US cdma2000)


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Creation of 3GPP and 3GPP2

Became clear that there was a great deal of commonalitybetween many of the standards being developed

all parties could see advantage of striving to achievecommonality

3GPP (3rd Generation Partnership Project) was formed inlate 1998

ETSI (Europe), ARIB (Japan), TTA (Korea), T1P1 (US), TTC(Japan) and CWTS (China) are members

But in practice, the representatives of these organizations areequipment vendors and network operators

3GPP produce specifications Regional standards bodies (e.g. ETSI, ARIB) are thenresponsible for issuing these as standards in the geographicregions for which they have a remit


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3GPP and 3GPP2

3GPP focus on developing standards for Direct Sequence WCDMA (DS-WCDMA)

FDD is stable in Release 99 of 3GPP All of the first 3rd generation products are based on this standard. Licences

being auctioned in Europe and those in Japan use this technology

Clear evolution path for GSM operators

TDD was not stable enough for implementation until Release00 of 3GPP

TDD based products became available in later time frame, as capacity increasingsolution

3GPP2 focuses on Multi Carrier WCDMA (MC-WCDMA) for cdma2000

Evolution path for US operators, as based on IS-41 Core Network with MC-WCDMA radio access

Long term: any radio access method should be possible to be used withany core network solution

Core network will probably evolve to All-IP based core


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CDMA was selected as multiple access technology for the radio interface

solution. The UMTS radio interface solution is often called WCDMA, because

CDMA is used on 5 MHz. Two duplex transmission solutions are available with UMTS Release 99, one

based on the TDD and one based on the FDD mode.

The introduction of a new radio interface solution required a new design of the

whole radio access network, which is called UTRAN.

CN evolution

There are more than 400 GSM operators worldwide. So one requirement to

UMTS Release 99 was to enable a smooth evolution from 2G to 3G.

Therefore, the UMTS Rel99 CN is an enhanced GSM NSS.

UMTS Release 99 (cont.)


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3GPP Release 4

The 3GPP Release 4 was functionally frozen in March 2001.

3GPP Release 4 is a further enhancement of 3GPP Release

1999.

3GPP Release 4 contains, but is not limited to

UTRA FDD repeater function

low chip rate TDD option

700 MHz support for GERAN,

e2e transparent packet streaming service

Tandem Free Operation

Transcoder Free Operation

IP transport of CN protocols

bearer independent CS core network

CAMEL enhancements and OSA enhancements.


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3GPP Release 5

The 3GPP Release 5 was functionally frozen in March 2002 and

the remaining part in June 2002.3GPP Release 5 is a further enhancement of the previousreleases.

3GPP Release 5 contains, but is not limited to,

High Speed Downlink Packet Access (HSDPA)

Initial phase of the IP Multimedia Subsystem (IMS)

Wideband AMR

Location Services enhancements

UMTS in 1800/1900 MHz bands (release independent)

IP transport in the UTRAN

UTRAN sharing in connected mode and security enhancements.


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3GPP Release 6The 3GPP Release 6 was functionally frozen in 2H/2004

3GPP Release 6 contain, but will not be limited to

FDD Enhanced Uplink (HSUPA)

FDD Enhanced Uplink - Physical Layer FDD Enhanced Uplink - Layer 2 and 3 Protocol Aspects

FDD Enhanced Uplink - UTRAN Iub/Iur Protocol Aspects

FDD Enhanced Uplink - RF Radio Transmission/ Reception, System PerformanceRequirements and Conformance Testing

Location Services enhancements 2

WLAN-UMTS Interworking Rel-6 Security

WLAN charging

USIM enhancements for WLAN Interworking

IMS Phase 2

Multimedia Broadcast/Multicast Service (MBMS)

Multimedia Messaging (MMS) enhancements

AMR-WB extension for high audio quality

Push Services and Presence

Network Sharing


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3GPP Release 7The 3GPP Release 7 was released during June 2007

3GPP Release 7 contain, but will not be limited to

HSPA Evolution (HSPA+)

Enhanced uplink, other spectrum, Multiple Input Multiple Output antennas (MIMO) and higher-order modulation

28 Mbit/s DL peak data rate

11 Mbit/s UL peak data rate

CPC - continuous packet connectivity

Always on user experience


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UMTS Release 99

UMTS Release 4

UMTS Release 5

UMTS Release 6

UMTS CN = enhanced GSM NSS

UTRAN & WCDMA

Bearer independent CS domain

Low chip rate TDD mode

UTRA repeater

MMS

etc.

High Speed Downlink Packet Access (HSDPA)

Wideband AMR

Initial phase of the IP Multimedia Subsystem

IP transport in the UTRAN

Location Services enhancements etc.

FDD Enhanced Uplink (HSUPA)

IMS Phase 2

Wireless LAN/UMTS Inter-working

Multimedia Broadcast/Multicast Service (MBMS)

Push Services and Presence.

etc.

1999

2001

2002

2006

UMTS Releases

UMTS Release 7 HSPA Evolution (HSPA+) Enhanced uplink, other spectrum,

Multiple Input Multiple Output antennas (MIMO)

and higher-order modulation

2007


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WCDMA Services

UMTS QoS Classes


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UMTS QoS Classes

UMTS attempts to fulfil QoS requests from the user

Four traffic classes have been identified Conversational

Streaming

Interactive

Background Main distinguishing feature is delay sensitivity

Conversational Class


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Conversational Class

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

Video telephony

Video Games

Streaming


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Streaming

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


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Interactive

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


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Background

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

UMTS QoS Classes


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UMTS QoS Classes

Conversational class Voice and video

Streaming class Streaming video

Interactive class

Web browsing

Background class

Mail downloading

WCDMA Applications


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WCDMA Applications

Information

IntelligentSearch and FilteringagentsInternet Surfing

On-line media

On-line translation

Local information

Booking & Reservation

News

Office InformationVirtual Working Groups

Tele-working

Schedule Synchronisation

Special ServicesSecurity Service

Hotline

Tele-medecine

Communications

Video TelephonyVideo Conferencing

Speech

Email

Announcing Services

SMS

Electronic Postcards

Financial Services

On-line bankingUniversal SIM & Credit Card

Home Shopping

Stock Quotes

TelemetricServicesMachine-Machine

Services

Location Based Tracking

Navigation Assistance

Travel Information

Fleet ManagementRemote Diagnostics

Public ServicesPublic Elections/Voting

Public Information

Help

Broadcast Services

Yellow Pages

LeisureVirtual Book Store

Music on Demand

Games on Demand

Video-clips

Virtual Sight Seeing

Lottery Services

EducationVirtual School

On-line Laboratories

On-line Library

On-line Training

Remote Consultation


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UMTS Air Interface Technologies

UMTS Air Interface technologies


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UMTS Air Interface technologies

UMTS Air interface is built based on two technologicalsolutions

WCDMA FDD

WCDMA TDD

WCDMA FDD is the more widely used solution FDD: Separate UL and DL frequency band

WCDMA TDD technology is currently used in limited numberof networks

TDD: UL and DL separated by time, utilizing same frequency

WCDMA FDD technology


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WCDMA FDD technology

Multiple access technology is wideband CDMA (WCDMA) All cells at same carrier frequency

Spreading codes used to separate cells and users

Signal bandwidth 3.84 MHz

Multiple carriers can be used to increase capacity

Inter-Frequency functionality to support mobility between frequencies

Compatibility with GSM technology Inter-System functionality to support mobility between GSM and UMTS

IMT-2000 frequency allocations


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q y

2200 MHz20001900 1950 2050 2100 21501850

JapanIMT-2000PHS

IMT-2000

ITUMobile

Satellit

e

IMT-2000 IMT-2000

EuropeUMTS

(FDD)DECT

UMTS(TDD)

GSM

1800

UMTS(TDD)

UMTS

(FDD)

USAPCS

unlicensed

PCSPCS

UMTS(TDD)

IMT-2000(TDD)

Mobile

Satellite

Mobile

Satellite

Mobile

Satellite

Mobile

Satellite

Mobile

Satellite

Mobile

Satellite

Mobile

Satellite

UMTS FDD Frequency band evolution


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q y

Release 99 I 1920 1980 MHz 21102170 MHz UMTS only in

Europe, Japan

II 18501910 MHz 19301990 MHz US PCS,GSM1900New in Release 5 III 1710-1785 MHz 1805-1880 MHz GSM1800

New in Release 6 IV 1710-1755 MHz 2110-2155 MHz US 2.1 GHz band V 824-849MHz 869-894MHz US cellular,

GSM850 VI 830-840 MHz 875-885 MHz Japan

New in Release 7 VII 2500-2570 MHz 2620-2690 MHz

VIII 880-915 MHz 925-960 MHz GSM900 IX 1749.9-1784.9 MHz 1844.9-1879.9 MHz Japan


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Differences Between WCDMA and GSM


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High bit rates

Spectralefficiency

Different qualityrequirements

Efficientpacket data

Downlinkcapacity

GSM system is TDMA based


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f1

f2

f1

f1

f2

f2

f3

f1

f1

f2

f2

f3

f3

f1

f2

f1

f3

f1M

S

1

M

S

2

M

S

3

M

S

4

BTS

Time

200 kHz

BTS

Typical GSM

Frequency

Usage

Pattern

MS = Mobile Station

Users divide the common

frequency by time slots

UMTS system is CDMA based


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f1 f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

MS1

MS2

MS3MS4

BS

Time

5 MHz

CDMA

Frequency

Usage

Pattern

MS1

MS2

MS3MS4

BSFDD = Frequency-division

duplex

Uplink and Downlink operate

in separated frequency bands

TDD = Time-division duplex

Uplink (UL) and downlink (DL)

use the same frequency band,

which is time-shared by the

UL and DL

All users share the same

frequency/time domain

WCDMA Key Benefits


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WCDMA Key Benefits

Soft Handover

Call is connected before handoff is completed, reducing

the probability of a dropped callProcessing Gain

basic CDMA benefit => the wider is the transmittedbandwidth compared to the user datarate the less poweris needed for the transmission

Advanced Radio Resource Management (RRM)

RRM will control call admission and packet schedulingand all RRM building blocks are closely related to eachother

Multipath Signal Processing

Combines power for increased signal integrity => RAKEreceiver


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UMTS Network Architecture

UMTS Network Architecture


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USIM

HLR

GMSC

RNC

MSC/

VLR

SGSN

RNC

Node B

Node B

Node B

Node B

ME

GGSN

PLMN: PSTN,

ISDN etc

Internet

Uu

Cu

Iub Iu r

Iu

UE UTRAN CN External Networks

UE and UTRAN


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User Equipment (UE) consists of two parts:

Mobile equipment (ME) is the radio terminal used for radiocommunication over the Uu interface.

UMTS Subscriber Identity Module (USIM) is a smartcard thatholds the subscriber identity, performs authenticationalgorithms, stores authentication and ciphering keys and alsosome user information

UTRAN (UMTS Terrestrial Radio Access Network) consistsof two types of entity:

Node B - base station

RNC - Radio Network Controller controls the Node Bs

connected to it

Node B Tasks and Functions


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Iub InterfaceATM

Uu InterfaceWCDMA

Cellular Transmission managementManaging ATM switching and multiplexing

over the Iub interface. Control of AAL2/AAL5connections. Control of the physical

transmission interfaces E1, PDH, SDH ormicrowave.

Air Interface management.Controlling Uplink and Downlink

radio paths on the Uu AirInterface. Baseband to RFconversion. Antenna multi-

coupling.

O&M Processing.Interfacing with NMS

and RNC for alarm andcontrol (Operations andMaintenance) functions.

Radio Channel functions.Transport to physical channel

mappings. Encoding/Decoding

Spreading/Despreading usertraffic and signalling.

RNC

Node B Tasks and Functions


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Core Network


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Core Network elements are:

HLR (Home Location Register) is a database that contains the

user's service profile. It is located in the user's home network.Typical information is allowed services, status of callforwarding etc. It also stores MSC/VLR when roaming, so thatincoming calls can be routed

MSC/VLR (Mobile Switching Centre/Visiting Location Register)

is the switch and database used by UE in its current locationfor circuit switched services

GMSC (Gateway MSC) is the point at which UMTS PLMN isconnected to externally circuit switched networks

SGSN (Serving GPRS Support Node) is similar to MSC/VLR,but for packet switched connections

GGSN (Gateway GPRS Support Node) is similar to GMSC butfor packet switched services

External Network


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The external networks can be divided into twogroups:

CS networks. These provide circuit-switchedconnections, like the existing telephony service. ISDNand PSTN are examples of CS networks.

PS networks. These provide connections for packetdata services. The Internet is one example of a PSnetwork.

Open interfaces of UMTS


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CN

Circuit

switched(cs)

domain

packetswitched

(ps)domain

UTRAN

Radio Network Subsystem (RNS)

Radio Network Subsystem (RNS)

Iub

Iub

Iur

Iu-PS

Iu-CS

Uu

Uu

UE

UE

MSC/VLR

SGSN

RNC

RNC



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Cu interface : This is the electrical interface between the USIMsmartcard and the ME.

Uu interface : This is the WCDMA radio interface, which is theinterface through which the UE accesses the fixed part of thesystem, and is therefore probably the most important openinterface in UMTS. There are many more UE manufacturers than

manufacturers of fixed network elements.

Iu interface : This connects UTRAN to the CN. Similarly to thecorresponding interfaces in GSM, A (Circuit Switched) and Gb(Packet Switched), the open Iu interface gives UMTS operatorsthe possibility of acquiring UTRAN and CN from differentmanufacturers.



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Iur interface : The open Iur interface allows soft handoverbetween RNCs from different manufacturers, and therefore

complements the open Iu interface.

Iub interface : The Iub connects a Node B and an RNC. UMTSis the first commercial mobile telephony system where theControllerBase Station interface is standardised as a fully openinterface.


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Radio Access Bearer Single Call (RU10)


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CS = circuit switched

PS = packet switched

QoS class Radio Access Bearer

PS Interactive / Background

PS I/B DCH/DCH

PS I/B DCH(16,64,128,384)/DL:HS-DSCH

PS I/B UL:E-DCH/DL:HS-DSCH

PS Streaming PS S DCH(8,16,32,64,128)/DCH(8,16,32,64,128,256)PS S DCH(16,64,128)/DL:HS-DSCH (not supported by NB/RSxxx via C-Iub)

PS S UL:E-DCH/DL:HS-DSCH (not supported by NB/RSxxx via C-Iub)


Speech AMR 12.2

AMR (12.2, 7.95, 5.90, 4.75)

AMR (5.90, 4.75)AMR-WB (12.65, 8.85, 6.6)

CS Conversational CS C DCH:64/DCH:64

CS Streaming CS S DCH(14.4)/DCH(14.4)

CS S DCH(57.6)/DCH(57.6)

Radio Access Bearer Multi Call (RU10)


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CS = circuit switched

PS = packet switched


Speech + 1-3 PS Interactive / BackgroundPS I/B DCH(0,8,16,32,64,128,256,384)/DCH(0,8,16,32,64,128,256,384)

PS I/B DCH(16,64,128,384)/HS-DSCH

PS I/B E-DCH/HS-DSCH

Speech + PS StreamingPS S DCH(8,16,32,64,128)/DCH(8,16,32,64,128,256,384)

PS S DCH(8,16,32,64,128)/HS-DSCH (not supported by NB/RSxxx via C-Iub)

PS S E-DCH/HS-DSCH (not supported by NB/RSxxx via C-Iub)

+ 0-3 PS Interactive / BackgroundPS I/B DCH(0,8,16,32,64,128,256,384)/DCH(0,8,16,32,64,128,256,384)

PS I/B DCH(16,64,128,384)/HS-DSCH


PS StreamingPS S DCH(8,16,32,64,128)/DCH(8,16,32,64,128,256,384)

PS S DCH(8,16,32,64,128)/HS-DSCH (not supported by NB/RSxxx via C-Iub)

PS S E-DCH/HS-DSCH (not supported by NB/RSxxx via C-Iub)

+ 1-3 PS Interactive / BackgroundPS I/B DCH(0,8,16,32,64,128,256,384)/DCH(0,8,16,32,64,128,256,384)

PS I/B DCH(16,64,128,384)/HS-DSCH


2-3 PS Interactive / BackgroundPS I/B DCH(0,8,16,32,64,128,256,384)/DCH(0,8,16,32,64,128,256,384)

PS I/B DCH(16,64,128,384)/HS-DSCH


CS Conversational CS C DCH(64)/DCH(64)

+ 1-3 PS Interactive / BackgroundPS I/B DCH(8,16,32,64,128,256,384)/DCH(8,16,32,64,128,256,384)

(0-2PS I/B with NB/RSxxx via C-Iub)

Multiple PS

RBs always

use the same

type of

transport

channel!


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WCDMA Fundamentals

Multiple Access Technologies


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The resource cube

in the radio environment many usersshare the same (common) resource

the whole resource space can becharacterized by:

Frequency plane Time plane

Code plane (sharing of signal power)

realization of multiple access technologies is achieved by sharingone or more of the planes between many users

Frequency

Multiple Access Techniques


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FDMA

User separation in the frequency domain

Ex. AMPS (30 KHz Channels each)

TDMA

User separation in the time domain

Ex. GSM

CDMA

User separation in the code (signal) domain

All users transmit data at the same time

and on the same frequency !!

Ex. IS 95, WCDMA

t

fS

1 2 3 4 5 6 1

t

S

11

11

11

f

t

f

1

2

3

4

5

6

S

FDD TDD


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FDD (Frequency Division Duplex)

separated frequency bands for Up- and Downlink

most suited for symmetrical services, e.g. voice, video telephony paired frequency bands needed

used in most of the WCDMA networks

TDD (Time Division Duplex) Up- and Downlink signal within the same frequency band, but separated in

time

also suited for asymmetrical services, e.g web browsing

Time synchronization needed

Preferable in indoor services

UL DL

5 MHz 5 MHz

t

DL

5 MHz

t

UL

The CDMA Cocktail Party


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..

Characteristics of (W)CDMA


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Multiple users can use the same frequency at the same time

Neighboring cells (can) use the same frequency

Separation of user access by assignment of different codes the user equipment scans all received signals for its own code, i.e. the input

signal is correlated to the assigned code

all signals with codes different from the own code appear as noise

High immunity to interference (interference rejecting technology) Increased bandwidth required due to(IS-95/cdma2000 1.25 MHz, W-CDMA 5 MHz)

Wid b d Di t S C d Di i i M lti l A

WCDMA Concept and Characteristics


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Wideband Direct Sequence Code Division Multiple Access

3.84 Mcps chip rate

Carrier spacing 4.4 to 5 MHz (200 kHz steps) Asynchronous base stations supported, no need for GPSsynchronization

Variable spreading and multi-code operation, SF = 4512 support for multi-rate services and bandwidth-on-demand concept

Coherent in both up- and downlink based on pilotsymbols/channels

FDD, standard supports coexistence of FDD and TDD modes

Frame length 10 ms user data rate can be changed

on a frame basis Designed for GSM co-existence

f

t

10 ms frame

4.4-5.0

MHzMultiplexed variable rate users

P

WCDMA Carrier


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5 MHz

3.84 MHz

f

5+5 MHz in FDD mode5 MHz in TDD mode

Fre

quency

Time

Direct Sequence (DS) CDMA

WCDMACarrier

WCDMA

5 MHz, 1 carrier

TDMA (GSM)

5 MHz, 25 carriers

Users share same time and frequency

Chip and Symbol Two Kinds of Bits


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Bit is binary representation of Information

A chip is a bit of the code signal used for signalmultiplication.

The code signal bit rate, which is hereafter referred to as

the chip rate, is fixed in WCDMA at 3.84 million chips persecond (Mcps/s).

With this chip rate the size of one chip in time is

1 / 38,40,000 seconds.


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Spreading Factor


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Spreading factor is a multiplier describing the number of chipsused in the WCDMA radio path per one symbol.

Spreading factor K can be expressed mathematically as follows:

K = 2k, where k = 0, 1, 2 8

For instance, if k = 6, the spreading factor K is 64, indicating thatone symbol uses 64 chips in the WCDMA radio path.

Another name for spreading factor is processing gain (Gp), and itcan be expressed as a function of used bandwidths.

B UU System Chip Rate

Gp= ----------------------- = ------------------------------- = Spreading Factor

B Bearer Bearer Symbols Rate

CDMA principle - Chips & Bits & SymbolsBits (In this drawing 1 bit = 8 Chips SF=8)


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Spreading Code

Spread Signal

Data

Air Interface

Bits (In this drawing, 1 bit = 8 Chips SF=8)

Baseband Data

-1

+1

+1

+1

+1

+1

-1

-1

-1

-1

ChipChip

Direct Sequence Spread Spectrum


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1

C

Bit Rate Ri=1/Bit Duration Ti

Different SSTs:

FH-CDMA

DS-CDMA

SST

Spread-

Spectrum

Technology

Only DS-CDMA

used for

civil mobile

communication

1

bit

1

0

1

1

1

0

0

0

1

.

.

.

SFchip

Chip Rate Rc=

1/Chip Duration Tc

Binary

data

Code

Signal

Code Sequence inverse Code Sequence

1

0

Bipolar

data

sequence

1Bit

+1

-1

+1

-1

+1

-1

0 1

1

Chip

DS-CDMA

Direct Sequence CDMA

Spreading Factor SF=

Chip Rate Rc/Bit Rate Ri

DS-CDMA Principle


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f

P 3NBI

WBI

MOD DEM LP DET(960 kb/s)

(3,84 Mc/s)

54321

Spreading Factor

g=R

chipR

bitP 4

P 5P

2

P1

f

Interference Rejection (Interference Averaging)

P Spread Spectrum


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The use of spreading codes results in an pulse-like peakfor the wanted signal after de-spreading and in a smallresidual signal level for all interferers.

f

f

PSpread Spectrum

Noise Floor Level

Wanted signal

Interferer 1

Interferer 2

Interferer n

f

P

Spectrum after De-spreading

(Processing)

Noise Floor Level

Interferer 1

Interferer 2

Interferer n

Combined level for

Noise and Interference

Wanted signal

C/I = 39 dB

Spreading & Processing Gain


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FrequencyPowerdensity(Watts/Hz)

Unspread narrowband signal Spread wideband signal

Bandwidth W (3.84 Mchip/sec)

User bitrate

R

sec84.3

MchipconstW

RW

dBGp Processinggain:

V i (R 12 2 kbit/ )

Processing Gain Examples


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Frequency (Hz)

Voice user (R=12,2 kbit/s)

Packet data user (R=384 kbit/s)

Powerdensity(W/Hz)

R

Frequency (Hz)

Gp=W/R=24.98dB

Powerdens

ity(W/Hz)

R

Gp=W/R=10 dB

Spreading sequenceshave a different length Processing gain dependson the user data rate

(User data rate) x(spreading ratio)=const.=W=3,84 Mcps

Unspread"narrowband"

signal

Unspread narrowband

signal

Spread widebandsignal

Spread widebandsignal

Transmission Power


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Frequency

5MHz

Power density

Time

High bit rate user

Low bit rate user


68/127


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WCDMA Codes

Scrambling Code

Only one primary scrambling code is allocated for a cell in the DL.


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The Primary CCPCH, which carries the cell information on thelogical BCCH channel, is transmitted by using the scrambling code.

The other downlink physical channels may use either the primaryscrambling code or a secondary scrambling code from the setassociated with the primary scrambling code of the cell.

In the uplink direction, there are millions of scrambling codesavailable. All uplink channels may use either short or longscrambling codes. Long codes are used if the base station usesthe RAKE receiver.

In the downlink direction, always long scrambling codes are used.

Channelization code : OVSF Codes


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Channelization codes are used for channel separation both inuplink and downlink direction.

In the downlink direction, only one dedicated physical channel isshared by the signaling and the application data. As a result,channel separation is the same as the user separation.

Channelization codes have different spreading factor values andtherefore different symbol rates.

There are a total of 256 short codes available under certainconditions.

The channelization code length is one symbol. For example, if thespreading factor is 4, then the channelization code contains 4

chips. One base band bit of data in the air interface is thereforedescribed with a 4-chip code.

Channelization code : OVSF Codes

Orthogonal variable spreading factor (OVSF) codes


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used as channelization codes in WCDMA

each channel from one transmitter is assigned its unique OVSF code

Code Properties:

code period is equal to one symbol period (channelization codes are used forsignal spreading!)

based on Walsh-functions

very good auto-correlation properties orthogonal cross-correlation properties, if perfectly synchronized different channels can be transmitted on the same scrambling code without

mutual interference, i.e. full separation of channels is possible in the receiver

strong synchronization requirement

maximum number of available codes is dependent on the codelength 2, 8, 16, 32, 64, 128, 256 (or 512) chips in WCDMA

Tree of Orthogonal Short Codes in DL

Hierarchical selection of short codes from a "code tree" to


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maintain orthogonality

Several long scrambling codes can be used within onesector to avoid shortage of short codes

C1(0) = [ 1 ]

C2(0) = [ 1 1 ]

C2(1) = [ 1 0 ]

C4(0) = [ 1 1 1 1 ]

C4(1) = [ 1 1 0 0 ]

C4(2) = [ 1 0 1 0 ]

C4(3) = [ 1 0 0 1 ]

C8(0) = [ 1 1 1 1 1 1 1 1 ]

C8(1) = [ 1 1 1 1 0 0 0 0 ]

. . .

. . .

Spreading factor:

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

C8(2) = [ 1 1 0 0 1 1 0 0 ]

C8(3) = [ 1 1 0 0 0 0 1 1]

. . .

. . .

C8(4) = [ 1 0 1 0 1 0 1 0 ]

C8(5) = [ 1 0 1 0 0 1 0 1 ]

. . .

. . .

C8(6) = [ 1 0 0 1 1 0 0 1 ]

C8(7) = [ 1 0 0 1 0 1 1 0 ]

. . .

. . .

Example ofcode allocation

Spreading in WCDMA

The spreading operation in WCDMA is done in two phases, both in uplink anddownlink


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downlink.

The first phase is done by using short codes.

The length of the short code is one symbol in chip units and the length is thusvarying according to the symbol rate.

The short codes are called spreading codes.

in downlink they orthogonalize the transmitted physical channels of one cell.

The second phase is done by using long codes.

The length of the long code is 36864 radio frames in uplink and one radio framein downlink.

The long codes are called scrambling codes.

The scrambling code of the downlink identifies the cell (sector), while in theuplink it identifies the call.

The spreading codes and in uplink also the scrambling codes are allocated by the system andrequire no actions in radio network planning. Allocating the downlink scrambling codes of thecells, or actually the scrambling code groups of the cells, can be part of the planning process.

PN Codes (pseudo noise)

Truncated Gold Codes


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used as scrambling codes in WCDMA

each base station and terminal is assigned a unique scrambling code (512primary codes and 15 secondary per primary available)

Code properties:

defined block length of an equal number of 1 and 0 with random statisticaldistribution in the blocks (noise-like = pseudo noise)

rather simple code generation by use of feedback shift registers

code period is much longer than the symbol (transmitted signal) period good auto-correlation properties (clear signal peak for correct code)

no major degradation in auto-correlation properties, if the codes are notperfectly synchronized between transmitter and receiver

maximizes probability of correct synchronization

Long and Short Codes

Short code = Channelisation code Long code = Scrambling code


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Short code = Channelisation code Long code = Scrambling code

Usage Uplink: Separation of physical data(DPDCH) and control channels

(DPCCH) from same terminalDownlink: Separation of downlinkconnections to different users withinone cell

Uplink: Separation of mobile

Downlink: Separation of sectors (cells)

Length 4256 chips (1.066.7 s)

Downlink also 512 chips

Different bit rates by changing the

length of the code

Uplink: (1) 10 ms = 38400 chips or (2)66.7 s = 256 chips

Option (2) can be used with advanced

base station receiversDownlink: 10 ms = 38400 chips

Number of codes Number of codes under one scramblingcode = spreading factor

Uplink: 16.8 million

Downlink: 512

Code family Orthogonal Variable Spreading Factor Long 10 ms code: Gold code

Short code: Extended S(2) code family

Spreading Yes, increases transmission bandwidth No, does not affect transmissionbandwidth

Spreading and Scrambling


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Single cell view:

all mobiles need to share the same frequency carrier - CDMA

orthogonal codes separate between the users and betweendifferent communication channels to one user (multi-codeoperation)

Channelization codes

Network view:

multiple transmitters (Node B, UE) need to coexist on thesame frequency and in the same geographic area - SSMA

nearly orthogonal codes to distinguish between thecommunication channels from different transmitters

Scrambling codes



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CC2CC1

CC3

CCn

Data

User 1

Cell

combiner

Filtering

Modulator,

Transmitter

Node B, sector 1

Data

User 2

Data

User 3

Data

User n

CC1CC2CC3

CCn

SC1

Data

User 1Filtering

Receiver,

Demodulator

UE 1CC1SC1

Data

User 2Filtering

Receiver,

Demodulator

UE 2CC2SC1

User

Data

1

User

Data

2

User

Data

3 User

Data

n

SC1

User

Data

1Noise

Noise Noise

CC2CC1

CC3 CCn

SC1



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CC2CC1

CC3

CCn

Data

User 1

Cell

combiner

FilteringModulator,

Transmitter

Node B, sector 1

Data

User 2

Data

User 3

Data

User n

CC1CC2CC3

CCn

SC1

Data

User 1Filtering

Receiver,

Demodulator

UE 1CC1SC1

Data

User 2Filtering

Receiver,

Demodulator

UE 2CC2SC1

User

Data

1

User

Data

2

User

Data

3 User

Data

n

SC1

User

Data

1Noise

Noise Noise

CC2CC1

CC3 CCn



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CC2CC1

CC3

CCn

Data

User 1

Cell

combiner

FilteringModulator,

Transmitter

Node B, sector 1

Data

User 2

Data

User 3

Data

User n

CC1CC2CC3

CCn

SC1

Data

User 1Filtering

Receiver,

Demodulator

UE 1CC1SC1

Data

User 2Filtering

Receiver,

Demodulator

UE 2CC2SC1

User

Data

1

User

Data

2

User

Data

3 User

Data

n

SC1

User

Data

1Noise

Noise Noise

SSMA - scrambling

CDMA - channelization

Physical Layer Bit Rates (Downlink)

Spreading Channel Channel DPDCH Maximum user


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Spreadingfactor

Channelsymbol

rate

(ksps)

Channelbit rate(kbps)

DPDCHchannel bitrate range

(kbps)

Maximum userdata rate with -

rate coding

(approx.)512 7.5 15 36 13 kbps

256 15 30 1224 612 kbps

128 30 60 4251 2024 kbps

64 60 120 90 45 kbps

32 120 240 210 105 kbps

16 240 480 432 215 kbps8 480 960 912 456 kbps

4 960 1920 1872 936 kbps

4, with 3parallel

codes

2880 5760 5616 2.3 Mbps

The number of orthogonal channelization codes = Spreading factor The maximum throughput with 1 scrambling code ~2.5 Mbps or ~100 full ratespeech users

Half rate speech

Full rate speech

128 kbps384 kbps

2 Mbps

The Radio Channel

M lti th ti Ti di i


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Multipath propagation Time dispersion

h()

0

0

1

23

1 2 3

WCDMA Receiver Input Signal


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tkl

Single user

tkl

Multiple users

tkl

Rake receiver principle

RAKE Receiver

Multipath signals reflected from obstacles and signals fromdifferent basestations can be combined using RAKE receiver


84/127



different basestations can be combined using RAKE receiver

RAKE receiver takes different factors (attenuation, timing) into

account and receiver fingers combine multipath signals to onesignal

X

X

X

a1

a2

a3

X

RAKE receiver

shadowing

distanceattenuation

multipath

Phase adjusting

delay1

delay2

delay3

The Rake Receiver

Each multipath component is called a finger


85/127



p p g

Estimation of radio channel properties for each finger:

delay

amplitude and

phase

The Rake receiver combines multipath componentswith a separation in time one chip period Tchip

WCDMA: 3.84 Mcps Tchip = 0.26 s 78 m

Increased chip rate resolves more paths (requiresmore processing)


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WCDMA Basic Functionality

What?

Power Control


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- The transmitter adapts the output power according to the Path Loss

Why?

-Mainly to solve the Near-Far problem.

- The goal is that all users should experience the same SIR (Signal to

Interference Ratio).

How?

- Outer quality control loop (Between Node B and RNC)

Open loop power control(Initially no signaling).

Closed loop power control(Signaling channel, continuously);1500 times/s, relative changes; up or down.

Power Control

Fast power control is vital for WCDMA performance. It aims tot l th t itt d th l l ith i d


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With Optimum

Power Control

Without

Power Control

MS1

MS2

MS3

MS4

MS1 MS2 MS3 MS4

ReceivedpoweratBS

ReceivedpoweratBS

MS1MS2

MS3

MS4

control the transmitted power on the same level with receivedpower. This leads to minimised interference and small powerconsumption

Power is controlled by parameters and needs to be definedduring network optimisation

P(SIR T t UL)

Power Control


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BLER = Block Error Rate

SIR = Signal to Interference Ratio

TPC = Transmit Power Control

P(Startvalue)

Open loop

P(SIR-Target,UL)

P(SIR-Target, DL)

Closed loop

DL-TPC UL-TPC

SIR-Target,DL

BLER-Measured,DL

DL-Outer loop

RNC

SIR-Target,UL

SIR-Error,UL

UL-Outer loop


90/127

Downlink Outer Loop PC

This function is implemented in the UE in order to set the SIR target for theDL closed loop PC.


91/127



DL closed loop PC.

This SIR value is adjusted according to an autonomous function of the UE

in order to achieve the same measured quality as the quality target set bythe RNC.

In order to control the downlink outer loop PC quality target in UE,Admission Control (AC) determines the value of the DL BLER target foreach DCH mapped on a DPCH.

After Admission Control functionality has determined the DL BLER target foreach transport channel, the RNC sends these values to the UE.

DL outer loop PC during the compressed mode (CM)

Different SIR targets are used during and after compressed frames

CM parameters provided by admission control are communicated to UE by RNC(Implemented in RAN 1.5)

Fast closed loop power control

20The closed loop power


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0 200 400 600 800

-20

-15

-10

-5

0

5

10

15

20

Time (ms)

Relativ

epower(dB)

Channel

Transmitted powerReceived power

control scheme is fast

enough to follow multipathfading for a wide range ofmobile speeds

Received Eb/No can bekept stable but on the

other hand transmittedpower is peaky

=> Received Eb/No can bekept low in spite ofmultipath fading, but fading

margin must be added totransmitted powers

Power control - Uplink

RNC Node-B UE


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qualityNew SIR target

Quality(BLER)target

Send TPC

(up/down)

to UEAdjust power

According to

Received TPCMeasure

received SIR

Measure quality

e.g. CRC Error

Outer loop Inner loop

Power Control combats fast fading

Without power control With power control


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TX power TX power

RX power RX power

t

t t

t

WCDMA medium bit rates

Service coverage

WCDMA high bit rate


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GSM voice

WCDMA voice and low bit rate

64/128 kbps 128/384 kbps

The power requirement determines the service coverage in WCDMA users will require different amount of power depending on environment, service,

system load

System load or rather intereference will depend on:

- Number of users in other/own cells, i.e. other/own average cell power usage

- distribution of users and their service usage

384 kbps

Load in neighboring cell impact the capacity and or thecoverage


96/127



Time

interference

Cell breathing

Max power High bit rate


97/127



The service coverage shrinks with increasing traffic in the cell

Medium bit rates

Low bit rate

Soft Handover

A UE communicates with several Node-Bs simultaneously

Soft handover possible and necessary with a one-cell frequencyreuse


98/127



From Cell ACell A Cell B

From Cell B

reuse.

Handover need to be very fast, since going a few dB into theneighbor cell will cause severe capacity loss.

Soft handover yields diversity gain less fast fading

New cell adjusts timing of the new dedicated channel

Why Soft Handover?

Soft handover essential for power control


99/127



p

Soft handover reception combines signals from different base stations

BS 1 BS 2

RNC

Different cell sets defined in 3GPP


100/127



= Active set

= Monitored set = Detected set

Active set - Cells the UE is connected to,- Size 1-4

M it d t C ll UE f t

Soft Handover


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Monitored set - Cells UE performs measurements on

- Union of all neighbor cells of the cells in active set Detected set - Strong intra freq. cells detected by UE.

- Cell reported as detected scrambling code

A UE need to detect and connect to a new good cell fast- Time constraints around 0.5 s

The terminal performs measurements on the CPICH- Three available quality estimates

Quality estimate Purpose- CPICH Ec/I0 Best quality- CPICH RSCP Received strongest- DL pathloss Nearest Node B

Softer Handover

The UE receives transmission from two or more cells in thesame Node-B


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Radio

Network

Controller

Maximum ratio combining in one RAKE in Node-B


103/127

GSM Inter-system Handover

Inter frequency measurements are needed to support inter system handover

Compressed mode supports these measurements


104/127



Inter system

WCDMAGSM time for measurementsTf= 10 ms

SF=SF0

SF=SF0/2

SF=SF0

Compressed mode

Handover types

Node B

Sector 1f1

Sector 2f1

Multipath Signalthrough Sector 1

Node B

Node B


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Soft Handover

Hard/Inter-Frequency Handover

SofterHandover

Inter-SystemHandover

Frequencyf1

Frequencyf1

Frequencyf1

Frequencyf2

UMTS GSM900/1800

Sector 3f1

through Sector 1

Multipath Signalthrough Sector 3

Frequencyf1

Frequencyf1

RNC RNC

Iur

Iub IubNode B Node B

Node B

Node B

Node B BTS

Channel Switching

Channel Type Switching


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Switch to

dedicated

Release dedicatedchannel

Random-AccessRequest

Random-Access Channel

Packet Packet Packet

Dedicated Channel

TTime-outSwitch tocommon

Random-AccessRequest

User 1 User 2

Channel Rate Switching

Channel rate switching

High bit rate


107/127



Channel rate switching provides contiguous packet service coverage

Provides high bit rates when possible

Provides robust service delivery

Medium bit rates

Low bit rate

Variable bitrate

Admission Control

Guarantees the overall Quality of Service bycontrolling the number of users


108/127



Interference

Capacity / Load

Planned load

Planned coverage

Coverage

New users blockedabove this point

User added

Admission

threshold

Logical description of Load Control

The purpose of load control is to optimise the capacity of a celland prevent overload situation.


109/127



Load control consists of Admission Control (AC) and PacketScheduler (PS) algorithms, and Load Control (LC), whichupdates the load status of the cell based on resourcemeasurements and estimations provided by AC and PS.

LC

AC

PSNRT load

Load changeinfo

Load status


110/127

Air Interface Access Stratum

L3Radio Resource

Control RRC

Control Plane

SignallingUser Plane

Information


111/127



L2

L1

Radio Link

Control RLC

Medium AccessControl MAC

Physical Layer

Logical

Channels

Transport

Channels

Physical

Channels

Logical Channels

Used with MAC layer (layer 2) for data transfer forhigher layers


112/127



g y

Broadcast Control Channel (BCCH)Paging Control Channel (PCCH)

Common Control Channel (CCCH)

Dedicated Control Channel (DCCH)

Dedicated Traffic Channel (DTCH)Common Traffic Channel (CTCH) *

Traffic Channels

Control Channels

* Implemented in RAN2.0

Transport Channels

Used for data transfer between MAC layer and Physical layer (L1)


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Broadcast Channel (BCH)

Random Access Channel (RACH)

Paging Channel (PCH)

Forward Access Channel (FACH)

Dedicated Channel (DCH)

Downlink Shared Channel (DSCH) *

Dedicated transport channels

Common transport channels


Physical Channels

In Layer 1, used for data transfer for MAC and higher layers


114/127



Physical Random Access Channel (PRACH)

Dedicated physical channels

Common physical channels


Common Pilot Channel (CPICH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

Synchronisation Channel (SCH)

Physical Downlink Shared Channel (PDSCH) *

Acquisition Indicator Channel (AICH)

Paging Indicator Channel (PICH)

Dedicated Physical Control Channel (DPCCH)

Dedicated Physical Data Channel (DPDCH)

Channel Mapping DL (Network Point of View

S-SCH

P-SCH

Logical

Channels

Transport

Channels

Physical

Channels


115/127



P-CCPCH

PCH

BCH

CTCH

DCCH

CCCH

PCCH

BCCH

DCH

CPICH

S-SCH

FACH

DSCH

CD/CA-ICH

AICH

PDSCHDPDCH

S-CCPCH

DTCH

PICH

DPCCH

Channel Mapping UL (Network Point of ViewLogical

Channels

Transport

Channels

Physical

Channels


116/127



DCCH

DCH DPDCHDTCH

CPCH

RACHCCCH

PCPCH

PRACH

DPCCH


117/127

Transport to Physical Channel Mapping

Transport Channels

DCH

Physical Channels



118/127



DCH

RACH

CPCH

BCH

FACH

PCH

DSCH


Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Common Pilot Channel (CPICH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

Synchronisation Channel (SCH)

Physical Downlink Shared Channel (PDSCH)

Acquisition Indication Channel (AICH)

Page Indication Channel (PICH)

Example of channel usage

SMS


119/127



UplinkDownlink

LogicalChannels

TransportChannels

PhysicalChannels

BCCHPCCH CCCHDCCH DTCH CCCH DTCH DCCH

BCH PCH FACH DCH DCHRACH CPCH

SCH1/2CCPCH-1CCPCH-2 DPCH(DPDCH+DPCCH)

PRACHDPDCHDPCCHPCPCH

CTCH

Signalling to Terminal

User Data to Terminal

Signalling to Network

User Data to Network

DSCH

PDSCH


120/127



HSDPA Basics

What is HSDPA?

HSDPA is an acronym for High Speed Downlink Packet Access.

HSDPA is part of the 3GPP standards since release 5. It wasintroduced in RNC in RN2 1


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introduced in RNC in RN2.1.

HSDPA is based on a technique where scheduling, link adaptationand physical layer retransmission handling is in the BTS improvingthe downlink packet data performance with the achieved highthroughput, peak rates and reduced delays.

HSDPA uses High-Speed Downlink Shared Channel (HS-DSCH)

as a transport channel. It is shared between users using channel-dependent scheduling to make the best use of available radioconditions.

HSDPA user traffic handling is divided so that downlink and uplinkdirections are using different transport channel i.e. HS-DSCH isused only for downlink direction and corresponding user planetraffic in uplink direction is transport via separate channel.

What is HSDPA?

HSDPA contains several technological enhancements. The increasein the downlink data rate and the actual cell throughput are due tothree main factors adaptive modulation and coding fast scheduling


122/127



three main factors, adaptive modulation and coding, fast scheduling,

and fast retransmission.

For HSDPA, the data rates used in the module are mainly peak data

rates. The actual data rates experienced by the user will be lowerbecause the radio channel used to transmit data to the subscribers istime shared between all HSDPA users in the cell. The channelconditions may also vary and cause more interference, which in turndecreases downloading speeds.

HSDPA General principle

Channel qualityinformation


123/127



Terminal 1

Terminal 2

L1 Feedback

L1 Feedback

Data

Data

Shared DL data channel

Fast link adaptation,scheduling and L1 errorcorrection done in BTS

1-5 codes in RAN05(max.15 codes RAN06)

QPSK or 16QAMmodulation

User may be time and/orcode multiplexed.

Error correctionAck/Nack

Maximum Bit Rates

Coding rate Coding rate 5 codes 10 codes 15 codes

HSDPABoth HSDPA and HSUPA aim to

increase

individual connection


124/127



QPSK

1/4

2/4

3/4

600 kbps 1.2 Mbps 1.8 Mbps

1.2 Mbps 2.4 Mbps 3.6 Mbps


16QAM

2/4

3/4

4/4




RAS05CD

RAS05 RAS06

throughput total cell throughput

Marketed bit rates do notrepresent RLC layerthroughput

HSDPA RLC throughputs are:

RAS05 1.6 Mbps

RAS05 CD 3.2 Mbps

RAS06 9.6 Mbps

Functionality

R99 DCH HSDPA


125/127



Notes:

3GPP allows multi-code transmission for R99 DCH but in practise only 1 code isused

The HSDPA user plane channel cannot use soft handover, although the associatedDCH may use soft handover

Variable spreadingfactor

Yes No

Multicode transmission Yes Yes

Adaptive modulation No Yes

Fast power control Yes No

Soft handover Yes NoNode B scheduling No Yes

Fast L1 HARQ No Yes

TTI 10, 20, 40 ms 2 ms

Main HSDPA featuresRAS05

PS interactive and background traffic classes

QPSK modulation

Max. 5 HS-PDSCH codes

RAS05.1

PS interactive and background traffic classes


No code multiplexing on HS-PDSCH


126/127



No code multiplexing on HS-PDSCHRound robin scheduling

Channel type switching to FACH on SHO areas

Max. 1 WSPC/BTS for HSDPA (16 users/BTS)

Theoretical max. throughput 1.6Mbit/s per BTS

Proportional fair schedulingHS-DSCH serving cell change

Associated DCH SHO

AMR + HSDPA calls

Max. 1 WSPC/cell (3 WSPC/BTS, 16 users/cell)

Theoretical max. throughput 3.6Mbit/s per cell

RAS05 CD

16QAM modulation

RAS06


Code multiplexing on HS-PDSCHDynamic resource allocation

48 users per cell

HSUPA


127/127



Thank You

UMTS Introduction & Wcdma HSDPA Fundmental JP

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