250
UMTS System Survey

UMTS System Survey

Embed Size (px)

DESCRIPTION

3G System Survay

Citation preview

Page 1: UMTS System Survey

UMTS System Survey

Page 2: UMTS System Survey

Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines

1. Before We Start

2. UMTS Introduction

4. UMTS Network Architecture.

3. WCDMA Concepts.

5. UMTS Air Interface Principles.

6. UMTS Procedures

7. UMTS services and applications

Page 3: UMTS System Survey

Before We Start Before We Start 11

Delegates for this course should be aware of the following topics:‐

Detention of Communication System.

Type of Communication according to medium typeType of Communication according to medium type.

Wire Communication.

Wireless Communication.

Type of Communication according to medium accessibility.

Simplex communication.

Half & Full duplex communication.

Concept of the modulation in the communication system, as well as different types of analog and digital modulation.

AM  ASK.

FM FSK.

PM PSK

Page 4: UMTS System Survey

Before We Start Before We Start 22

Delegates for this course should be aware of the following topics:‐

Digital Vs Analog communication.

Digital communication principlesDigital communication principles.

Sampling.

Quantization.

Source coding and channel coding.

Modulation and Shannon theory. 

Different Multiple access techniques.

TDMA

FDMAFDMA

CDMA

Circuit switching and Packet switching concept.

Page 5: UMTS System Survey

Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines

1. Before We Start

2. UMTS Introduction

4. UMTS Network Architecture.

3. WCDMA Concepts.

5. UMTS Air Interface Principles.

6. UMTS Procedures

7. UMTS services and applications

Page 6: UMTS System Survey

00G: MTS Mobile telephone SystemG: MTS Mobile telephone System

System DescriptionSystem DescriptionIntroduced in the late 40’s, by AT&T.

High power transmitter at high elevationHigh power transmitter, at high elevation.

First time to introduce the mobility.

Analog System FM; 120KHz BW enhanced to 30KHz….Max 12CH

No coverage continuity.

Initially half duplex system; upgraded to a full duplex one in 1950.

Very limited capacity and low quality

CallWashington Baltimoredropped

g

Page 7: UMTS System Survey

11G:AMPS Advanced Mobile Phone ServiceG:AMPS Advanced Mobile Phone Service

System DescriptionSystem DescriptionThe first introduction of the cellular concept.

F t Wh f h thFreq reuse concept When you are far‐enough away you can re‐use the channel

Many Cells with low power; instead of few cells with high power.

Analog based system (FM).

Low quality.

Introducing the Handover concept.

Ch #1 Ch #2 Ch #3 Ch #1

Reuse DistanceReuse Distance

Page 8: UMTS System Survey

First generation different standardFirst generation different standard

Page 9: UMTS System Survey

22G:GSM global system of mobile communicationG:GSM global system of mobile communication

System DescriptionSystem DescriptionA complete digital system (FDMA / TDAM).FSK modulation (GMSK).Better quality (coding) and quality (encryption) than 1G.124 Ch at 900MHz.45MHz duplex distance45MHz duplex distance.Voice service only.Better Utilization TDMA vs. analog.

Page 10: UMTS System Survey

GSM SpectrumGSM Spectrum

GSM900 890‐915 / 935‐960 MHz

E‐GSM 880‐915 / 925‐960 MHz

GSM1800 1710‐1785 / 1805‐1880

GSM1900 1850 1910 / 1930 1990 MHzGSM1900 1850‐1910 / 1930‐1990 MHz

GSM‐R 876‐880 / 921‐925 MHz

GSM450 450.4‐457.6 / 460.4‐467.6 MHz

GSM480 478.8‐486 / 488.8‐496 MHz

GSM850 824‐849 / 869‐894 MHz

Page 11: UMTS System Survey

PDC

Second generation different standardSecond generation different standard

GSM:Global System for 

PDC:Personal Digital Cellular

since 1993/94J lMobile Communication

since 1992world‐wide:

≈ 165 countries

Japan only800 & 1500 MHz

≈ 70 M. subscriber

900, 1800 & 1900 MHz

subscriber: ≈ 550 M.

IS‐95:Interim Standard‐95

since 1995

D‐AMPS:Digital AMPS

welt‐wide, America & S. Korea

800 & 1900 MHz, 1700 MHz (Korea)

since 1991/92USA, Canada800 & 1900 MHzAMPS/D‐AMPS ( )

≈ 100 M. subscribersubscriber: ≈ 90 M.

Page 12: UMTS System Survey

22G system Evolution.G system Evolution.

22

Page 13: UMTS System Survey

22G system Evolution.G system Evolution.

Page 14: UMTS System Survey

22G system Evolution.G system Evolution.

GPRS (GPRS (22..5 5 G)G)Stands For General Packet Radio System.Introduced in the late 90’s.System is capable of packet switching in addition to circuit switchingSystem is capable of packet switching in addition to circuit switching.GSM structured network; (Core network impacted).Data rate up to 20Kb/s per time slot and maximum of 160Kb/s.Pure PS rather than HSCSD.

EDGE (EDGE (22..75 75 G)G)Stands Enhanced data GPRS evolution.

d dIntroduced in 2001.GSM/GPRS structure network.Enhancing data rate up to 59Kb/s per time slot and 473Kb/s.8 PSK modulation instead of GMSK.

2Radio network impact.

2

Page 15: UMTS System Survey

UMTS UMTS 33G DriversG Drivers

Consumer demand for widebandConsumer demand for widebandservices

Imaging

Wireless postcardMobile transactions

Increased network capacity

More airtime Access anytime, anyplaceMore Subscribers

Page 16: UMTS System Survey

Mobile TrendMobile Trend

100 VoiceData

60

80

[%]

Data

40

60

Traf

fic [

20

T

Trend: Voice ⇒ Data

01996 2001 2005 2007

YYear

Page 17: UMTS System Survey

Mobile TrendMobile Trend

Page 18: UMTS System Survey

UMTS DriverUMTS Driver

Video conferences

video telephony

Tele‐Shopping

Electronic newspapersImages / Sound files

Tele‐BankingFinancial services

Images / Sound filesUMTS offers

flexible & dynamicdata rates:

8 kbit/ 2 Mbit/Data base access

Information services

E il

8 kbit/s ‐ 2 Mbit/s

E‐mail

Voice

10 100 1000 10.000Data rate [kbit/s]

Page 19: UMTS System Survey

33G ServicesG Services

VOICE Improved Voice Quality 

CAPACITY Voice & Data Usage 

Mobile TV Streaming TV session with data rate 128Kb/s

SPEED Higher bit rates: up to 384 kbps

Mobile TV

Video telephone Video Telephony with data rate starting from 64kb/s

Mobile Navigation Precise Location based Services

Page 20: UMTS System Survey

UMTS developmentUMTS development

ETSI(Europe) TIA, T1

(USA)

ARIB, TTC(Japan)

( )

CATT( )

TTA(South Korea)

(China)

ESA Iridium(South Korea)

ICO, Inmarsat

ESA, Iridium(MSS)

(MSS)

Page 21: UMTS System Survey

UMTS developmentUMTS development

Page 22: UMTS System Survey

UMTS development UMTS development 33GPP foundationGPP foundation

ETSIEuropean Telecommunication

Standards Institute ARIB/TTCAssociation of Radio IndustriesTTA

3GPP

& Business / TelecommunicationTechnology Committee, Japan

GSAGlobal Mobile Supplier

Association

TSACCTelecommunication

Standards Advisory Council

Telecommunications TechnologyAssociation, South Korea

IPv63GPP3rd Generation

Partnership Project

UMTSForum

TIATelecommunicationIndustry Association,

USA

of Canada

UWCCUniversal WirelessC i ti

IPv6Forum

ACIF

CWTSChina Wireless

Telecommunications GSM

CommunicationsConsortiumWMF

Wireless MultimediaForum

MWIFMobile WirelessInternet Forum3G.IP

Forum

ACIFAustralian Communications

Industry Forum

Standards Association

MPR: Market Representation Partner

Organisational Partner

Observership status

ANSI T1Committee T1

Telecommunications

Page 23: UMTS System Survey

UMTS developmentUMTS development

Page 24: UMTS System Survey

IMTIMT--2000 2000 road maproad map

Page 25: UMTS System Survey

UMTS standardization UMTS standardization

• Standardization organizations such as 3GPP, 3GPP2 were established3GPP2 were established 

WCDMA CDMA2000

3G system

WCDMA

3GPP

FDD/TDD mode

CDMA2000

3GPP2

Page 26: UMTS System Survey

Spectrum AllocationSpectrum Allocation

Page 27: UMTS System Survey

33G system Evolution.G system Evolution.

UMTS RUMTS R99 99 ((33G)G)Stands for Universal mobile telecommunication systemIntroducing the WCDMA technique for mobile communication.60MH t ll ti t 2G60MHz spectrum allocation at 2G.12 CHs at 5MHz BW per channel.QPSK modulation.Different stream of services as data rate increases and extra capcity.p y

HSDPA (HSDPA (33.X G).X G)Stands Enhanced High speed data packet access.h h d h h h f ll hEnhancing the data rate through the following technique.5 simultaneously codes 2Mb/s.5 simultaneously codes & 16 QAM modulation 3.6Mb/s.10 simultaneously codes & 16 QAM modulation 7.2Mb/s.

20 s u ta eous y codes & 6 Q odu at o b/s15 simultaneously codes & 16 QAM modulation 14.4Mb/s.

HSDPA speed is increasing rapidly.(MIMO, 32QAM, 2 carrier coherent 80Mb/s)2

Page 28: UMTS System Survey

Egypt’s Mobile Spectrum AllocationEgypt’s Mobile Spectrum Allocation

GSM 900

Vodafone

Mobinil

Etisalat

Purchased & Active

Reserved for operator

MHz        880 890 902.5                               915 925 935 947.5                              960                               

UL

E‐GSM

DL

E‐GSM

Etisalat

GSM 1800

Channels                               1                                           62 63                                        124                             975  1023  0

MHz          1710     1715                              1751     1756      1761       1766                      1785                       1805     1810                             1846      1851     1856       1861                    1880

1763 5 1858 5

Channels   512         538                              716        741       766  778 791                       885

DL

1763.5 1858.5

UL

UMTS

UL

MHz             1920          1925          1930          1935        1940          1945          1950          1955          1960          1965 1970          1975          1980  

DL

MHz            2110         2115          2120         2125          2130          2135          2140          2145          2150          2155 2160          2165          2170  

Channels                     9612               9637              9662              9687            9712              9737 9762 9787              9812 9837 9862               9887

DL

Channels                    10562            10587             10612           10637            10662            10687          10712              10737  10762           10787            10812            10837                        

Page 29: UMTS System Survey

TerminologiesTerminologies

UMTSUMTSUniversal mobile telecommunication system.Refer to the entire network.All h id d d i b llAll the systems can considered under its umbrella.

WCDMA  (UTRAWCDMA  (UTRA‐‐FDD)FDD)The Access network that based on the WCDMA‐FDD slandered .

UTRANUTRANUniversal terrestrial radio access network.Include the WCDMA access network; except for the UE (userInclude the WCDMA access network; except for the UE (user 

equipment) 

RANRANRadio access network

2Radio access network.Define the different types of the radio access networks (WCDMA‐GSM‐

GPRS….etc). 2

Page 30: UMTS System Survey

Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines

1. Before We Start

2. UMTS Introduction

4. UMTS Network Architecture.

3. WCDMA Concepts.

5. UMTS Air Interface Principles.

6. UMTS Procedures

7. UMTS services and applications

Page 31: UMTS System Survey

W(W)CDMA history (evolution)(W)CDMA history (evolution)

19001900 First human voice transmission  (Reginald Fessenden)

19481948 J h Pi d ib CDMA M lti l i

19061906 First radio broadcast (Fessenden)

19481948 John Pierce describes CDMA Multiplexing

19491949 Claude Shannon & John Pierce describe major CDMA effects

19561956 "Anti‐multi path" RAKE receiver patented

19701970ss CDMA used in several military communication and navigation systems

19801980ss Studies for narrowband CDMA for commercial mobile networks

19931993 USA used CDMA standardised in 2nd generation

19901990ss Studies for wideband (~5 MHz) CDMA for mobile cellular systems 

19961996 UMTS forum established

g

19971997 ITU requests proposals for candidate radio transmissiontechnologies for IMT‐2000 radio interface

Page 32: UMTS System Survey

(W)CDMA history (evolution)(W)CDMA history (evolution)

19981998 3GPP formed to develop of a joint 3G system based on evolved GSM core and UTRA air interface

19991999 ETSI starts UMTS project20032003 Commercial use of WCDMA network20052005 First commercial launch of HSDPA networkFirst commercial launch of HSDPA network

Page 33: UMTS System Survey

Old and New school in RF Bandwidth Utilization Old and New school in RF Bandwidth Utilization 

Multiple Access different techniquesMultiple Access different techniques

Page 34: UMTS System Survey

CDMA optionsCDMA options

Di t d f h i CDMADi t d f h i CDMADirect sequence and freq hopping CDMADirect sequence and freq hopping CDMA

Page 35: UMTS System Survey

The CDMA PartyThe CDMA Party

What do YOU hear...

•If you only speak Japanese?

•If you only speak English?

•If you only speak Italian?y y p

•If you only speak Japanese, but the Japanese-speaking person is all the way across the room?

•If you only speak Japanese, but the Spanish-speaking person is talking very loudly?

Page 36: UMTS System Survey

One Cell Frequency ReuseOne Cell Frequency Reuse

In WCDMA, all cells may use the same carrier frequency but different scrambling codes. This means no frequency planning, but scrambling code and power planning instead!

FDMA/TDMA (reuse > 1) CDMA/WCDMA (reuse = 1)

Page 37: UMTS System Survey

CDMA conceptCDMA concept

(C1D1 + Perfect orthogonally

C1 * C2 = 0

C1 * C3 = 0

(C1D1 + C2D2 + C3D3)

Perfect orthogonally  

Number of users (capacity) are C1   C3   0

C1 * C1 = 1

C2 * C3 = 0

Number of users (capacity) are related to the number of codes.

Rate of codes must be higher than 

C2 * C2 = 1

C3 * C3 = 1

the data. (as the code length increase the code rate increase)

So spreading must be used which p gminimize power per user

Page 38: UMTS System Survey

Coding Concept …Coding Concept …

Receiver and Transmitter use identical code at same time offset

Input Data +1 -1 +1

+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1PN code used

in Transmitter

x x x

Transmitter

+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1TransmittedSequence

= = =

+1 +1 +1 +1 +1 +1 +1 +1 -1 –1 –1 –1 –1 –1 –1 -1 +1 +1 +1 +1 +1 +1 +1 +1

= = =

+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1PN CodeUsed in Receiver

x x x

Receiver

1 1 1Divide by

+8 -8 +8

IntegrateResult

Integrate Integrate Integrate

+1 -1 +1Divide byCode Length

Page 39: UMTS System Survey

Coding Concept…Coding Concept…

Input Data +1 1 +1

Receiver and Transmitter use two uncorrelated codes at same time offset

Transmitter

Input Data +1 -1 +1

Orthogonal codein Transmitter

x x x

= = =+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1

TransmittedSequence

= = =

x x x

+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1

+1 +1 +1 +1 +1 +1 +1 +1

+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1

Orthogonal different Code

used in Receiver

x x x

= =Receiver

+1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1

=

0 00

IntegrateResult

0Divide by

Integrate IntegrateIntegrate

0 00Code Length 0 0

Page 40: UMTS System Survey

Coding conceptCoding concept

+1

‐1

ChipChip

Rate matched baseband 

Data

Code +1

‐1

ChipChip

Data xCode

+1

‐1Scrambling

Code +1DespreadingDespreading

Uu

‐1

Data +1

‐1

Page 41: UMTS System Survey

Interference limited system Interference limited system

Page 42: UMTS System Survey

Spreading concept in CDMASpreading concept in CDMA

de

Two Transmitters at the same frequency

PN Code 1Frequency

Am

plit

ud

Signal 1

Both signals combinedin the air interface

Am

plit

ude

Signal 2

PN Code 2Frequency

A

Spread SpectrumAT THE RECEIVER...

⎟⎠⎞

⎜⎝⎛=

Rate DataRate Code PN

Spread SpectrumProcessing Gain

Both signals arereceived together

AT THE RECEIVER...

PN Code 1 Signal 1 is reconstructedSignal 2 looks like noise

Page 43: UMTS System Survey

Spreading and Power Spectral DensitySpreading and Power Spectral Density

The shapes of power spectral density (Power / Hz) are very different between b(t) and y(t).

The total power (total area) is equal, however it has been spread over a greater bandwidth.

Spreading does not change total power. Spreading p g g p p gchanges how the power is distributed over frequency

Page 44: UMTS System Survey

Spreading and Power Spectral DensitySpreading and Power Spectral Density

As Power of b(t) = Power of y(t)

fPSDfbPSD

Having fc >> fb we can now define Processing Gain G

fcPSDfbPSD tytb .. )()( =∴

g g

ctb

ff

PSDPSD

=∴ )(

G (processing gain) = fc/fb 

fb =1/Tb (the bit rate of the input signal)

bty fPSD )(

fb =1/Tb (the bit rate of the input signal) 

fc =1/Tc (the chip rate of the spreading code) 

Page 45: UMTS System Survey

processing gain conceptprocessing gain concept

• Digital SNR: Eb/No

bb R

SE = Energy per bit (Eb) equals the average signal power (S) divided by the data bit rate (Rb)

BNN =0

Noise power density (N0)The total noise power in the signal bandwidth, divided by the signal bandwidth

Energy per bit (Eb) - to - Noise RatioThe Signal-to-Noise Ratio (SNR) times the SSMA Processing Gain

pbb

b GSNRRB

NS

NRS

NE

⋅=⎟⎟⎠

⎞⎜⎜⎝

⎛=⎟⎟

⎞⎜⎜⎝

⎛=

00

1

Page 46: UMTS System Survey

CDMA Rx ConceptCDMA Rx Concept

• Correlation of channel codes in receiver• Own channel correlates well, i.e. peaks (Signal)• Other channels appear as noise (Interference)• More users → increased interference

Power

• More users → increased interference

Signal (Eb)

1 Carrier (5MHz)

Interference (No)

Power need to be adjusted to retain the Signal to Interference Ratio (SIR)I.e. fulfilling the BLER requirements for that specific service

Page 47: UMTS System Survey

CDMA Rx Concept (CDMA Rx Concept (22//22))

If the BLER requiresPower

+G

+5 dB

If the BLER requiresA Eb/No of 5dB for a certain service and the processing gain (Gp) is

Gp Signal (Eb)

p g g p25dB for the service,

it means a C/I down to

Interference& Noise (No)

–20 dB

–20 dB is still acceptable

Gp

1 Carrier (5MHz)

)Rc/Rilog(10 ⋅−= NoEb

IC

Rc : Chiprate 3.84 Mc

Gp

Ri : Service bitrate

Page 48: UMTS System Survey

Drivers behind Spread Spectrum signals Drivers behind Spread Spectrum signals 

•• SecuritySecurity

• Harder for eavesdropper to detect, jam and interfere. 

•• Wider Scope of ApplicationsWider Scope of Applications

Narrow Signal

PowerWider Scope of ApplicationsWider Scope of Applications− Higher Bandwidth available for user gives more varieties 

for supported applications.

•• Higher System CapacityHigher System Capacity− Depending on unique nature of codes spreading to− Depending on unique nature of codes spreading to 

distinguish different users on same carrier.− Simplified system planning from a frequency reuse of 

1, which allows the same RF carrier frequency to be used in every cell or sector throughout a system. y g y

•• Better system quality.Better system quality.− Enhanced RF channel performance (reduced fading) due 

to unique reception techniques. − Enhanced call quality Better and more consistent sound

Spread Spectrum Signal

Frequency

Enhanced call quality. Better and more consistent sound. − A more reliable transport mechanism for wireless data 

communications. − Reduced interference from other sources. − Lower transmit RF power levels, longer battery life, andLower transmit RF power levels, longer battery life, and 

increased talk time for hand‐held units. 

Page 49: UMTS System Survey

Related Terms and DefinitionsRelated Terms and Definitions

TermTerm DefinitionDefinition• Narrow Band Signal Signal occupies a relatively small bandwidth 

i.e. (GSM signal has 200KHz bandwidth)

• Wide Band Signal Signal occupies relatively wide bandwidthi.e. (WCDMA signal has 5 MHz bandwidth)

• Pseudo Noise Signal Signal has a noise like behaviour actual noise never repeats ‐

• Spreading Converting a signal with low bit rate into another signal p g g g gwith much higher bit rate 

• Scrambling Converting a signal into another coded version of it keeping the same bit ratep g

Page 50: UMTS System Survey

Related Terms and DefinitionsRelated Terms and Definitions

• Auto Correlation                   Measurement for how much a signal is related to another version of  itself

• Cross Correlation     Measurement for how a signal is related  to another   different signal

• Orthogonal Codes Codes has Auto Correlation = 1 and

Cross Correlation = 0

• Pseudo Noise Codes  Codes has Auto Correlation very close to 1 and

Cross Correlation very close to 0

Page 51: UMTS System Survey

Multiple users spreading and dispreadingMultiple users spreading and dispreading

Page 52: UMTS System Survey

Multiple users spreading and dispreadingMultiple users spreading and dispreading

Page 53: UMTS System Survey

Repeated Spreading and ScramblingRepeated Spreading and Scrambling

Repeated spreading and scrambling used inRepeated spreading and scrambling used in

• Channel identification 

• Transmitter identification

Page 54: UMTS System Survey

Types of Codes in WCDMATypes of Codes in WCDMA

• Two important types of digital codes are specified. 

Scrambling Codes

Pseudo Noise sequences that appear as random noise to all but the service– Pseudo Noise sequences that appear as random noise to all but the  service provider and its particular client. But they actually do repeat. 

– Have very good correlation properties, but not completely orthogonal.

Channelization/Spreading Codes (TheWalsh functions Orthogonal codes )Channelization/Spreading Codes (The Walsh functions, Orthogonal codes )

– Data channels channelization code length depends on user data rate

– Control channels channelization code length fixed by standard

– Have the highly desirable property of orthogonality

Page 55: UMTS System Survey

Properties of MProperties of M--Sequences (PN codes)Sequences (PN codes)

1- Blanca property: – Number of one’s = Number of zero + 1

2- Run property:2 Run property:The total number of runs = (N + 1) / 2

– Sequence contains one run of ones, length m– One run of zeros, length m-1, g– One run of ones and one run of zeros, length m-2– Two runs of ones and two runs of zeros, length m-3– 2m-3 runs of ones and 2m-3 runs of zeros, length 1

3 A t l ti P t3- Autocorrelation Property – The periodic autocorrelation of a ±1 m-sequence is

( ) otherwise

... 2N, N,0,

11 =

⎩⎨⎧−

τR

Page 56: UMTS System Survey

PN Code GenerationPN Code Generation

• PN Codes:  Generation using a Shift Register

D D D D

β1 β2 β3 βN

clock

1010010010001110101...

• βn values are 0 or 1 (determined by the specified “generator polynomial”)

• Maximal-length (m-sequence) has a repetitive cycle of ( 2N - 1 ) bits

• A code of 32,768 bits can be replicated using only a 15-bit “key”

Page 57: UMTS System Survey

Generation of Scrambling CodeGeneration of Scrambling Code

• Generated using  Linear Feedback Shift Register Circuitry

• Codes in uplink uses 25 bit key to differentiate between different UEs

• Codes in downlink uses 18 bit key to differentiate between different Node Bs

• Both DL and UL code length is only first 38400 chip of the generated sequence

• Only 8192 Codes used in downlink speed up search process for Node BOnly 8192 Codes used in downlink speed up search process for Node B

• The 8192 codes are divided into 

• 64 code group ( each has 8 primary codes) , so 512 Primary code

• Each primary code has 15 secondary codes

Page 58: UMTS System Survey

Properties of MProperties of M--SequencesSequences

1 0 0O/P

The output m sequence = 0011101

CLK

1 0       0

1.Balance property

No of ones = 4 , No of Zeros = 3

1        1 0

1        1       1

0 1 1

2.Run property

Total no of runs = 40        1       1

1        0       1

0        1       0

o/p = 00 111 0 1

–Sequence contains one run of ones, length m= 3

One run of zeros length m 1 = 20         0      1

–One run of zeros, length m-1 = 2

–One run of ones and one run of zeros, length m‐2 = 1

Page 59: UMTS System Survey

Gold Sequences

• Gold sequences constructed by the XOR of two m-sequences with the same clocking

• They can supply large number of code.y pp y g• They have very good cross correlation properties

Page 60: UMTS System Survey

Generation ofGeneration of Scrambling CodeScrambling Code

• Downlink Scrambling CodesU d di i i h B S i i i– Used to distinguish Base Station transmissions on Downlink

• Each Cell is assigned one and only one Primary Scrambling Codeg y y g

• The Cell always uses the assigned Primary Scrambling Code for the Primary and Secondary CCPCH’s

• Secondary Scrambling Codes may be used over part of a cell, or for other data channels

8192 Downlink Scrambling CodesEach code is 38,400 chips of a 218 - 1 (262,143 chip) Gold Sequence

Code Group #1 Code Group #64

Primary SC0

Secondary Scrambling

Codes

(15)

Secondary Scrambling

Codes

(15)

Secondary Scrambling

Codes

(15)

Secondary Scrambling

Codes

(15)

Primary SC7 Primary SC504 Primary SC511

( ) ( ) ( ) ( )

Page 61: UMTS System Survey

Scrambling CodeScrambling Code

Uplink: PN Code used to distinguish each Mobile StationDownlink: PN Code used to distinguish each Base Station

PN1 PN1

Cell Site “1” transmits using PN code 1

g

PN3 PN4

PN2 PN2

Cell Site “2” transmits using PN code 2

PN5 PN6

Page 62: UMTS System Survey

SSMA PN Code PlanningSSMA PN Code Planning

Spread Spectrum Code Planning Example

N

PN2

PN2

PN3

N

W E

PN2

PN1

PN2

PN3PN7

PN6 PN4

PN1

PN3PN7

PN6 PN4

PN5 PN1

PN2

PN3PN7S

PN1

PN2

PN3PN7

PN6 PN4

PN1

PN3PN7

PN6 PN4

PN5 PN1

PN2

PN3PN7

PN5 PN6 PN4

PN5

PN6 PN4

PN5

PN5 PN1

PN6 PN4

PN5

Page 63: UMTS System Survey

Orthogonal Code CorrelationOrthogonal Code Correlation

• Orthogonal Code correlation– Code correlated with itself ‐‐> 100% correlationCode correlated with itself  > 100% correlation

– Code is correlated with another orthogonal code ‐‐> 0% correlation

– Code time alignment is essential

Autocorrelation of Walsh 34 Walsh 3460 Autocorrelation of Walsh 34, Walsh 34Integration Sum = 64 at time offset = 0

-20

02040

60

Cross-correlation of Walsh 34, Walsh 47Integration Sum = 0 at time offset = 0

10 20 30 40 50 60-60-40

4060

Integration Sum = 0 at time offset = 0

-60-40-20

02040

Poor cross-correlation properties at time shifts other than zero!10 20 30 40 50 60

Page 64: UMTS System Survey

Orthogonal Codes conceptsOrthogonal Codes concepts

• When you send data using Orthogonal Codes...Orthogonal Code

Transmitted “chips”Data

Orthogonal Code

User 1 Data:

1 0 1

XOR with Walsh Code

1010

User 1 Walsh-spread Data:

0101 1010 0101

You send one orthogonal (e.g., Walsh) code for every data bit!

If you want to send a “0”, you transmit the assigned Walsh Code

If you want to send a “1”, you transmit the inverted Walsh Code

Page 65: UMTS System Survey

Orthogonal Codes conceptsOrthogonal Codes concepts

• Orthogonal Code Transmitter

Data Channel 1

0 1 0

Data Channel 2

XOR with OC1

( 1111 )

XOR with OC2

After XOR

(1111)(0000)(1111)

After D/A Mapping

(----)(++++)(----)

After XOR After D/A Mapping

0 0 1 ( 1100 )∑

Data Channel 3

1 0 1

XOR with OC3

( 1010 )

(1100)(1100)(0011) (--++)(--++)(++--)

After XOR

(0101)(1010)(0101)

After D/A Mapping

(+-+-)(-+-+)(+-+-)

C it T itt d D t

Data Channel 4

0 0 0

XOR with OC3

( 1001 )

After XOR

(1001)(1001)(1001)

After D/A Mapping

(-++-)(-++-)(-++-)

Composite Transmitted Data:

(-2 -2 +2 -2) (-2 +2 +2 +2) (0 0 0 -4)4-chip Orthogonal Code Set

1) 1 1 1 12) 1 1 0 03) 1 0 1 03) 1 0 1 04) 1 0 0 1

Page 66: UMTS System Survey

Orthogonal Codes Orthogonal Codes conceptsconcepts

• Orthogonal Code ReceiverComposite Received Data:

4-chip Orthogonal Code SetAnalog representation)

1) -1 -1 -1 -12) -1 -1 +1 +1

Integrate & Result:

“Correlation”

(-2 -2 +2 -2)(-2 +2 +2 +2)(0 0 0 -4)

XOR with OC1

3) -1 +1 -1 +14) -1 +1 +1 -1

Map A→DIntegrate &

Normalize

Integrate &

Result:

1 -1 1

Result:

XOR with OC1

(-1 -1 -1 -1)

XOR with OC2

Map A→D

0 1 0

Map A→D

Normalize

Integrate &

Normalize

1 1 -1

Result:

-1 1 -1

(-1 -1 +1 +1)

XOR with OC3

(-1 +1 -1 +1)

0 0 1

Map A→D

1 0 1

Integrate &

Normalize

Result:

1 1 1XOR: Exclusive-Or multiplication

( )

XOR with OC4

(-1 +1 +1 -1)

Map A→D

0 0 0

Integrate: Sum four consecutive values after XOR

Normalize: Multiply by [ 1 / code length]

Page 67: UMTS System Survey

Orthogonal Codes conceptsOrthogonal Codes concepts

Downlink: Orthogonal Codes used to distinguish data channelsC i f h B St ti

OC1, OC2OC3, OC4

Coming from each Base Station

OC5, OC6, OC7

Uplink: Orthogonal Codes used to distinguish data channelscoming from each Mobile Station

OC1 , OC2, OC3OC1, OC2

OC1, OC2, OC3, OC4

Page 68: UMTS System Survey

Orthogonal Code GenerationOrthogonal Code Generation

• Generation of Orthogonal (Walsh) Codes1

11 1011 10

1111 1100 1010 1001

11111111 11110000 11001100 11000011 10101010 10100101 10011001 1001011011111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110

Digital/Analog Mapping

logic 0 ↔ analog +1logic 1 ↔ analog - 1

1100110011001100

Page 69: UMTS System Survey

Orthogonal Codes conceptsOrthogonal Codes concepts

• orthogonal Code Space:  5 users; one user has 4x data bandwidth

Chi R t 3 840 M1

User with 2x Bit Rate

1 92 MSymbol/s

Chip Rate = 3.840 Mcps

11 101.92 MSymbol/s11 10

1111 1100 1010 1001

11111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110

= Unusable Code Space

480 kSymbol/s 480 kSymbol/s

11111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110

Page 70: UMTS System Survey

Orthogonal Codes Orthogonal Codes conceptsconcepts

• Spreading Factor=Processing Gain= Rc/Rb

• Different spreading is done according to the service bit rate as the chip rate is constant.

٧٠

Page 71: UMTS System Survey

Code Locking Concept (PN Codes)Code Locking Concept (PN Codes)

• PN codes is generated not stored 

• Synchronization between Node B and  UEl l d dis extremely important to correctly decode 

original information

WCDMA bil C d L ki• WCDMA mobiles use Code Lockingcircuitry to lock on Scrambling code. 

Page 72: UMTS System Survey

Code Locking Concept (Orthogonal Codes)Code Locking Concept (Orthogonal Codes)

• TX, RX use same codes and same time offset

• Orthogonal Codes 100% gcorrelation

• TX, RX use same codes, but different time offset

• Orthogonal Codes Unpredictable results Orthogonality lost

• TX, RX use different codes• Orthogonal Codes 0% Correlation

Page 73: UMTS System Survey

Code CorrelationCode Correlation

Case I: Autocorrelation using a PN CodeReceiver and Transmitter use identical code at same time offset

Input Data +1 -1 +1

+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1PN code used

in Transmitter

x x x

Transmitter

+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1TransmittedSequence

= = =

+1 +1 +1 +1 +1 +1 +1 +1 -1 –1 –1 –1 –1 –1 –1 -1 +1 +1 +1 +1 +1 +1 +1 +1

= = =

+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1PN CodeUsed in Receiver

x x x

Receiver

1 1 1Divide by

+8 -8 +8

IntegrateResult

Integrate Integrate Integrate

+1 -1 +1Divide byCode Length

Page 74: UMTS System Survey

Code CorrelationCode Correlation

Case II: Cross-Correlation using PN CodesReceiver and Transmitter use different codes

Input Data +1 -1 +1

+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1PN code used

in Transmitter

x x x

Transmitter

+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1TransmittedSequence

= = =

-1 +1 –1 +1 +1 –1 -1 +1 +1 -1 +1 –1 +1 +1 –1 -1 -1 +1 +1 +1 –1 -1 +1 +1

-1 –1 –1 +1 –1 +1 –1 -1 -1 –1 –1 +1 +1 +1 +1 -1 -1 –1 +1 +1 +1 +1 +1 -1

PN CodeUsed in Receiver

x x x

= = =Receiver

-4 0 2

IntegrateResult

Divide by

Integrate Integrate Integrate

-0.5 0 0.25Divide by

Code Length

Page 75: UMTS System Survey

Code CorrelationCode Correlation

Input Data +1 1 +1

Case III: Correlation using Orthogonal Codes(a) Same Orthogonal code (b) Different Orthogonal codes (c) Same code with non-zero time offset

Transmitter

Input Data +1 -1 +1

-1 +1 –1 +1 +1 –1 +1 -1 -1 +1 –1 +1 +1 –1 +1 -1 -1 +1 –1 +1 +1 –1 +1 -1Orthogonal code

in Transmitter

x x x

= = =-1 +1 –1 +1 +1 –1 +1 -1 +1 –1 +1 –1 –1 +1 –1 +1 -1 +1 –1 +1 +1 –1 +1 -1Transmitted

Sequence

= = =

x x x

1 Chip shift

-1 +1 –1 +1 +1 –1 +1 -1 +1 +1 +1 +1 +1 +1 +1 +1 -1 -1 +1 –1 +1 +1 –1 +1

+1 +1 +1 +1 +1 +1 +1 +1 +1 –1 +1 –1 –1 +1 –1 +1 +1 –1 –1 –1 +1 –1 –1 -1

Orthogonal Codeused in Receiver

x x x

= = =Receiver

8 0 -4

IntegrateResult

+1 0 0 5Divide by

Integrate Integrate Integrate

+1 0 -0.5Code Length

Page 76: UMTS System Survey

Scrambling and Channeliztion codesScrambling and Channeliztion codes

Page 77: UMTS System Survey

SummarySummary

SC1

SC1SC1

SC1

SC1

Page 78: UMTS System Survey

Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines

1. Before We Start

2. UMTS Introduction

4. UMTS Network Architecture.

3. WCDMA Concepts.

5. UMTS Air Interface Principles.

6. UMTS Procedures

7. UMTS services and applications

Page 79: UMTS System Survey

Different UMTS releasesDifferent UMTS releases

Release Release 99 99 feature. feature. New Radio Interface (UTRA)

FDD and TDD at 3.84 Mcps.GSM/GPRS HandoverGSM/GPRS Handover.Support for Multi-call (CS & PS) simultaneously.Location service over Air Interface.Basic UMTS security.yCore network was compatible with the GSM/GPRS networks

Release Release 4 4 feature feature TDD at 1 28 McpsTDD at 1.28 Mcps.Evolution of core network transport to IP.

ReleaseRelease 55 featurefeatureRelease Release 5 5 feature feature Evolution of UTRAN transport to IPIP based Multimedia service.High-Speed Downlink Packet access (HSDPA).g p ( )

Page 80: UMTS System Survey

WCDMA RWCDMA R99 99 Network ArchitectureNetwork ArchitecturePSTNISDN

GSM /GPRS BSS

BTS

BSC

MSC/VLR GMSC

HLR/AUC

ISDN

BTS

RNC

PCU

SMS

SCE

HLR/AUC

SS7

NodeB SCP

SMS

SGSN

GPRS backbone/ Internet,Intranet

SGSN GGSN

User  UTRAN Network Core NetworkEquipment Domain Access Network 

Domain

Access stratum

Non Access stratum

Access stratum

Page 81: UMTS System Survey

WCDMA RWCDMA R99 99 Network ArchitectureNetwork Architecture

Page 82: UMTS System Survey

11--Core Network DomainCore Network Domain

Structure of the CN.Structure of the CN.

Page 83: UMTS System Survey

11--Core Network DomainCore Network Domain

F ti f th CNF ti f th CNFunction of the CN.Function of the CN.Connection Management (CM),

Provides the bearer services and the procedures for circuit-switched connections (RAB handling; Call control handling).switched connections (RAB handling; Call control handling).

Session Management (SM)Responsible for the set up, monitoring and release of a packet-

switched connection (PDP handling).Mobility Management (MM)

Determine the location of a User Equipment so a connection can be set up. 

Circuit switching (Detach; Ideal and activeCircuit switching (Detach; Ideal and activelocation update and paging).Packet switching (Idle; ready and standby routing area update and paging).

Handling the mobility of the user in order to keep cell continuity in the active mode.

Page 84: UMTS System Survey

11--Core Network DomainCore Network Domain

Connection management.Connection management.

Page 85: UMTS System Survey

11--Core Network DomainCore Network Domain

S i M tS i M tSession ManagementSession Management

Page 86: UMTS System Survey

11--Core Network DomainCore Network Domain

M bilit M tM bilit M tMobility ManagementMobility Management

Page 87: UMTS System Survey

11--Core Network DomainCore Network DomainCircuit Switching DomainCircuit Switching Domain

MSC FunctionMSC FunctionSignaling switching and call routing to or from MS.Charging.Service provisioningService provisioning.Control of connected RNC’s.One MSC controls more than one RNC.

GMSC FunctionGMSC FunctionAccess to PSTN.Access to PSTN.Provides the gateway functionality/Interface

to other networks.

Page 88: UMTS System Survey

11--Core Network DomainCore Network DomainCircuit Switching DomainCircuit Switching Domain

VLR FunctionVLR FunctionAssociated with MSCSubscriber Management in MSC area.Authentication co ordinationAuthentication co-ordination.Commands start of ciphering.

VLR DataVLR Data

MSC/VLR

VLR Data.VLR Data.A temp data base that holding the following information

Subscriber data from HLR.MSISDN; IMSI…etc.Services available and restrictions.

Temp subscriber information.TMSI; LAI; triples….etc.

The VLR hold these data for the subscriber included in theThe VLR hold these data for the subscriber included in the MSC area only.

Page 89: UMTS System Survey

11--Core Network DomainCore Network DomainRegister and Service domainRegister and Service domain

HLR FunctionHLR FunctionThe HLR is a centralized (unique) network database that stores and manages all mobile subscriptions.

IMSI, MSISDNServices subscribedService restrictions (e.g. roaming restrictions)Parameters for additional servicesParameters for additional servicesInfo about user equipment (IMEI)Authentication data

Temporary informationTemporary information Link to current location of the user:Current VLR address (if avail)Current MSC address (if avail)MSRN (if user outside PLMN)

Page 90: UMTS System Survey

11--Core Network DomainCore Network DomainRegister and Service domainRegister and Service domain

Other nodes for the register domain.Other nodes for the register domain.AUC: authentication center.EIR: equipment identity register. IN: intelligent network.BGW: belling gateway.SMSC: short message service center.

Page 91: UMTS System Survey

11--Core Network DomainCore Network DomainPacket switching domainPacket switching domain

SGSN FunctionSGSN FunctionForwards incoming and outgoing IP packets addressed

to/from a mobile station that is attached within the SGSN service areaservice area.

Provides packet routing and transfer to and from the SGSN service area.

Ciphering and authenticationSession managementMobility managementLogical link management toward the MSOutput of billing dataOutput of billing data.

SGSN

Page 92: UMTS System Survey

11--Core Network DomainCore Network DomainPacket switching domainPacket switching domain

GGSN FunctionGGSN FunctionThe interface towards the external IP

packet networks.pActs as a router Exchanges routing information with the

external network.GPRS session managementGPRS session management,

communication setup toward external network.

Output of billing data.

Page 93: UMTS System Survey

22. Access Network Domain. Access Network Domain

Page 94: UMTS System Survey

22--Acess NetworkAcess Network

F ti f th A t kF ti f th A t kFunction of the Access network.Function of the Access network.Responsible of the radio resources management.Consists of several Radio network subsystem (similar of BSS in GSM).

One RNCOne RNC.Several node Bs.

Page 95: UMTS System Survey

22--Acess NetworkAcess NetworkRNC functionRNC function

F ti f th RNCF ti f th RNCFunction of the RNC.Function of the RNC.Control several node Bs/ interface with the core network (MSC/SGSN).Radio resources management.Admission and congestion control.Admission and congestion control.Handover and power control (outer loop).Ciphering/deciphering. Can softly be divided into 3 types

CRNC ControlCRNC ControlSRNC ServingDRNC Drift

Page 96: UMTS System Survey

22--Acess NetworkAcess NetworkRNC functionRNC function

P C t l i RNCP C t l i RNCPower Control in RNC.Power Control in RNC.Open loop power controlclosed loop power controlOuter loop power controlOuter loop power control

Page 97: UMTS System Survey

22--Acess NetworkAcess NetworkNode B functionNode B function

F ti f th N d BF ti f th N d BFunction of the Node B.Function of the Node B.Contains the RF equipment that provide

the radio link in the air interface.More intelligent than BTS.More intelligent than BTS.Perform spreading/dispreading, channel

coding, also responsible of a part of the power control (inner loop).

Ciphering using the ciphering key.Records and passes to the RNC the

Signal strength measurements

Mapping of Transport channels into physical channels

Page 98: UMTS System Survey

33-- User Equipment domain User Equipment domain

Function of the User Equipment domain .Function of the User Equipment domain .The end user node; that provide the services/application to the users.The new generation of UMTS phones will combine the advantages of g p g

wireless communication with the demand for multimedia applications Consists of.

User Terminal.

UMTS Subscriber Identity Module (USIM)

UE

Page 99: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

F ti f UTF ti f UTFunction of UT.Function of UT.Radio transmission termination.Radio channel management.Speech encoding / decoding.Speech encoding / decoding.Flow control of data.Mobility management.Call control. Performance meas rement of radio linkPerformance measurement of radio link.SIM card interface service provider and network registration/ deregistrationlocation updatepsetup of connectionless / connection-oriented servicesunalterable equipment identification (IMEI). basic identification of the User Equipment's capabilitiesemergency calls without a SIMemergency calls without a SIM execution of algorithms required for authentication and encryption

Page 100: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

N F ti f UTN F ti f UTNew Functions of UT.New Functions of UT.

Page 101: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

M lti d i tM lti d i tMultimode user equipmentMultimode user equipment

Page 102: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

M lti d i tM lti d i tMultimode user equipmentMultimode user equipment

Page 103: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

T f i t (TT f i t (T 11 / T/ T 22))Types of user equipment (Type Types of user equipment (Type 11 / Type / Type 22))

Page 104: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

T f i t (TT f i t (T 33 / T/ T 44))Types of user equipment (Type Types of user equipment (Type 33 / Type / Type 44))

Page 105: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

IMEI f t d f tiIMEI f t d f ti

Final Assembly Codes (FAC)

IMEI format and function.IMEI format and function.UE is uniquely identified by the IMEI.Used by the EIR for terminal authentication and for capabilities identification

TAC(6 digits)

FAC (2 digits)

SNR (6 digits)

SVN (2 digits)

Final Assembly Codes (FAC)

01 ,02 AEG

07 ,40  MotorolaTAC: Type Approval CodeTAC: Type Approval Code10 ,20   Nokia

40,41,44,  Siemens

l l

TAC: Type Approval CodeTAC: Type Approval CodePlaces that is centrally assigned by a GSM body.

47 Optional International

51 Sony

51 Siemens

SNR: Serial NumberSNR: Serial NumberUnique serial number assigned by the manufacturer

51 Ericsson

60 Alcatel

SVN: Software version NumberSVN: Software version NumberRefer to the version of software

Page 106: UMTS System Survey

33-- User Equipment domain User Equipment domain User TerminalUser Terminal

USIM USIM function.function.

Stores user addressesIMSI,MSISDN,TIMSI, rooming, etc

Authentication and encryption features

subscriber’s secret authentication key (Ki)subscriber s secret authentication key (Ki)

Security Algorithm & Keys (for Authentication, Ciphering,..).

PersonalizationSIM t fil ( b ib d i )SIM stores user profile (subscribed services)RAM available for SMS, short numbers, user’s directory, etcProtection codes PIN ,PUK

Page 107: UMTS System Survey

Core Network Evolution.Core Network Evolution.RR99 99 Vs RVs R44

SCP HLR SCP HLR

CS domain evolution

TUP/ISUP

MAP Over TDM MAP Over TDM/IP

ATM/IP/TDMMSC MSC

TDMMSC Server

ATM/IPMGW MGW

MSC ServerTUP/ISUP

ATM/IP

ATM/IP/TDM

RAN RAN RAN RAN RAN RAN

ATM/IP

R99 R4

PS domain structure remain unchangedPS domain structure remain unchanged

Page 108: UMTS System Survey

WCDMA RWCDMA R4 4 Network ArchitectureNetwork Architecture

MGWMGW MGWMGW

IP/ATM Backbone

PSTN

HLR/AUC

MSC Server GMSC Server

PSTNISDN

NodeB

RNC

SMS

SCE

HLR/AUC

SS7

UTRAN SCP

SMS

SGSNGGSN

GPRS backbone Internet,IntranetUTRAN Network

GGSNUser

Equipment Domain

Access Network Domain

Access stratumCore Network

Access stratumNon Access stratum

Page 109: UMTS System Survey

MSC ServerMSC Server

MSC server.MSC server.Call control and routing for mobile-

originated and mobile-terminated calls; gMobility managementintegrates with (VLR) which holds

location information;Providing authentication functions;Providing authentication functions;terminates signaling

Page 110: UMTS System Survey

Media GatewayMedia Gateway

Media gateway server.Media gateway server.This translates media traffic between different

types of network.ypTermination of bearer channels;MSC server is able to support several MWGs;

Page 111: UMTS System Survey

SummarySummary

Page 112: UMTS System Survey

Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines

1. Before We Start

2. UMTS Introduction

4. UMTS Network Architecture.

3. WCDMA Concepts.

5. UMTS Air Interface Principles.

6. UMTS Procedures

7. UMTS services and applications

Page 113: UMTS System Survey

WCDMA Frequency AllocationsWCDMA Frequency AllocationsWCDMA Frequency AllocationsWCDMA Frequency Allocations

2025 2110FDD UPLINK TDD FDD DOWNLINK

1920 1980 2010 2170

WCDMA /EUROPE

1850 1910

FDD UPLINK1930 1990

WCDMA / USA FDD DOWNLINKTDD

TDD1900

2025 2110

IMT-2000 MSS MSS IMT-2000 MSS MSS

1885 1980 2010 2160 2170 2200

ITU/WARC-95

2025 2110

IMT-2000 MSS IMT-2000 MSS

1900 1980 2010 2170 2200

DECT

1880

Europe

2025 2110

IMT-2000 MSS Terrestrial MSS

1918.1 1980 2010 2170 2200

PHS

18951885

Japan

2025 2110

MSS MSS

1900 1980 2010 2170 2200

FDD WLL

1880

CDMA

1865 1920 1945 1960

TDD WLL CDMA FDD

WLLChina

2025 21101900 1980 2010 2170 220018801865 1920 1945 1960

2025 2110

MSS

2185 2200

A

1850 1910 1930 1990

D B E F C A D B E F C MSS BroadcastAuxiliary Reserved

2150

USA

Part 4:  113 of 65

Page 114: UMTS System Survey

WCDMA StandredsWCDMA StandredsWCDMA StandredsWCDMA Standreds

3GPP WCDMA O i• 3GPP WCDMA OverviewBoth FDD (2x 5 MHz) and TDD (1x 5 MHz)modes supported

• Operation specified in bands between 1850 and 2170 MHzBS time synchronization not required for FDD mode 

• GPS not required• Fast Synchronization Codes allow asynchronous operation and handoverS h i i ll d ll f i i i i f• Synchronous operation is allowed; allows faster acquisition, interference reduction

Multi‐Code and Variable Spreading Factor modes supportedNetwork interface compatible with GSM ‐MAP / GPRSNetwork interface compatible with GSM  MAP / GPRS

• * To be made compatible with ANSI‐41 per OHG requirementPhysical Parameters:

• Chip rate = 3.840 Mcps• RF Bandwidth =  5 MHz• Physical Layer data rates of 15, 30, 60, 120, 240, 480, 960, and 1920 kb/sec• Payload data rates of 12.2, 64, 128, 144, 384, 768, and 2048 kb/sec• Frame length = 10 mSec and15 time slot = 0.667 mSec• Fast Power Control:  Bi‐directional; 1500 updates/sec

Page 115: UMTS System Survey

WCDMA moduleWCDMA moduleWCDMA moduleWCDMA module

Page 116: UMTS System Survey

WCDMA Physical ChannelsWCDMA Physical ChannelsWCDMA Physical ChannelsWCDMA Physical Channels

P-CCPCH- Primary Common Control Physical ChannelSCH - Synchronization Channel

Channels broadcast to all UE in the cell

P-CPICH - Primary Common Pilot ChannelS-CPICH - Secondary Common Pilot Channel(s)

PICH - Paging Indicator Channel

Paging Channels

S-CCPCH - Secondary Common Control Physical Channel

BaseStation

(BS)

UserEquipment

PICH Paging Indicator Channel

PRACH - Physical Random Access Channel

AICH - Acquisition Indicator Channel

Random Access and Packet Access Channels

( )(UE)PCPCH – Physical Common Packet Channel

AP-AICH - Access Preamble Acquisition Indicator ChannelCD/CA-AICH -Collision Detection/Ch.Assignment Indicator Ch.CSICH - CPCH Status Indicator Channel

DPDCH - Dedicated Physical Data Channel

DPCCH - Dedicated Physical Control Channel

PDSCH Ph i l D li k Sh d Ch l

Dedicated Connection Channels

PDSCH - Physical Downlink Shared Channel

Page 117: UMTS System Survey

UMTS Channels mappingUMTS Channels mappingUMTS Channels mappingUMTS Channels mapping

Page 118: UMTS System Survey

Release Release 4 4 ChannelsChannelsRelease Release 4 4 ChannelsChannels

Page 119: UMTS System Survey

Release Release 5 5 channelschannelsRelease Release 5 5 channelschannels

Page 120: UMTS System Survey

PCCPCHPCCPCHPCCPCHPCCPCH

Page 121: UMTS System Survey

PCCPCHPCCPCHPCCPCHPCCPCH

Page 122: UMTS System Survey

PCCPCHPCCPCHPCCPCHPCCPCH

Page 123: UMTS System Survey

CPICHCPICHCPICHCPICH

Page 124: UMTS System Survey

(P & S)(P & S)‐‐CPICHCPICH(P & S)(P & S)‐‐CPICHCPICH

Page 125: UMTS System Survey

SCHSCHSCHSCH

Page 126: UMTS System Survey

SCCPCHSCCPCHSCCPCHSCCPCH

Page 127: UMTS System Survey

PICHPICHPICHPICH

Page 128: UMTS System Survey

PRACH and FACHPRACH and FACHPRACH and FACHPRACH and FACH

Page 129: UMTS System Survey

AICHAICHAICHAICH

Page 130: UMTS System Survey

SCCPCHSCCPCHSCCPCHSCCPCH

Page 131: UMTS System Survey

DPDCHDPDCH

Page 132: UMTS System Survey

DPDCH & DPCCHDPDCH & DPCCHDPDCH & DPCCHDPDCH & DPCCH

Page 133: UMTS System Survey

DL DPDCHDL DPDCHDL DPDCHDL DPDCH

Page 134: UMTS System Survey

UL DPDCHUL DPDCHUL DPDCHUL DPDCH

Page 135: UMTS System Survey

UL DPDCHUL DPDCHUL DPDCHUL DPDCH

Page 136: UMTS System Survey

Downlink Data RatesDownlink Data RatesDownlink Data RatesDownlink Data Rates

• Variable Data Rates on the Downlink:  ExamplesBits/Frame Bits/ Slot Channel Bit

R t Channel S b l

SF

DPCCH Rate

(kbps) Symbol

Rate (ksps)

TOTAL DPDCH DPCCH TOTAL DPDCH

TFCI TPC PILOT

15 7 5 512 150 60 90 10 4 0 2 4 15 7.5 512 150 60 90 10 4 0 2 4

120 60 64 1200 900 300 80 60 8 4 8

1920 960 4 19,200 18,720 480 1280 1248 8 8 16

Channel Coding

Coded Data1.920 Mb/sec

(19,200 bits per 10 mSec frame)

S/P Converter

(OVSF codes at 3.84 Mcps)

960 kb/sec

per 10 mSec frame)

Page 137: UMTS System Survey

Downlink DPDCH/DPCCH Slot FormatsDownlink DPDCH/DPCCH Slot FormatsDownlink DPDCH/DPCCH Slot FormatsDownlink DPDCH/DPCCH Slot Formats

DPDCHBits/Slot

DPCCHBits/Slot

SlotFormat

#i

ChannelBit Rate(kbps)

ChannelSymbol

Rate(k )

SF Bits/Slot

Transmittedslots per

radio frameN

3GPP TS 25.211¶ 5.3.2

(ksps) NData1 NData2 NTPC NTFCI NPilotNTr

0 15 7.5 512 10 0 4 2 0 4 150A 15 7.5 512 10 0 4 2 0 4 8-140B 30 15 256 20 0 8 4 0 8 8-141 15 7.5 512 10 0 2 2 2 4 15

1B 30 15 256 20 0 4 4 4 8 8 14

Notes:

1) Z TFCI l t f t 1B 30 15 256 20 0 4 4 4 8 8-142 30 15 256 20 2 14 2 0 2 15

2A 30 15 256 20 2 14 2 0 2 8-142B 60 30 128 40 4 28 4 0 4 8-143 30 15 256 20 2 12 2 2 2 15

3A 30 15 256 20 2 10 2 4 2 8-143 60 30 128 0 2 8 1

1) Zero-TFCI slot formats are used when there is only one data service on the DCH.

2) Slot formats A and B are used during

14 480 240 16 320 56 232 8 8* 16 1514A 480 240 16 320 56 224 8 16* 16 8-14

3B 60 30 128 40 4 24 4 4 4 8-14 compressed mode operation

14B 960 480 8 640 112 464 16 16* 32 8-1415 960 480 8 640 120 488 8 8* 16 15

15A 960 480 8 640 120 480 8 16* 16 8-1415B 1920 960 4 1280 240 976 16 16* 32 8-1416 1920 960 4 1280 248 1000 8 8* 16 15

16A 1920 960 4 1280 248 992 8 16* 16 8-14

Part 4:  137 of 65

Page 138: UMTS System Survey

Uplink DPDCH/DPCCHUplink DPDCH/DPCCHUplink DPDCH/DPCCHUplink DPDCH/DPCCH

• Uplink DPDCH/DPCCH Slot Formats 3GPP TS 25.211 ¶ 5.2.1

DPDCH (Dedicated Physical Data Channel) Slot Formats

Slot Format #i Channel Bit Rate (kbps)

Channel Symbol Rate (ksps)

SF Bits/ Frame

Bits/ Slot

Ndata

0 15 15 256 150 10 10 1 30 30 128 300 20 20 2 60 60 64 600 40 40 3 120 120 32 1200 80 80

DPDCH (Dedicated Physical Data Channel) Slot Formats

4 240 240 16 2400 160 160 5 480 480 8 4800 320 320 6 960 960 4 9600 640 640

Slot Channel Bit Channel Symbol SF Bits/ Bits/ Npilot NTPC NTFCI NFBI T ransmitted DPCCH (Dedicated Physical Control Channel) Slot Formats

Format #i

Rate (kbps) y

Rate (ksps) Frame Slot p ot C C

slots per radio frame

0 15 15 256 150 10 6 2 2 0 15 0A 15 15 256 150 10 5 2 3 0 10-14 0B 15 15 256 150 10 4 2 4 0 8-9 1 15 15 256 150 10 8 2 0 0 8-15 2 15 15 256 150 10 5 2 2 1 15

2A 15 15 256 150 10 4 2 3 1 10-142A 15 15 256 150 10 4 2 3 1 10-142B 15 15 256 150 10 3 2 4 1 8-9 3 15 15 256 150 10 7 2 0 1 8-15 4 15 15 256 150 10 6 2 0 2 8-15 5 15 15 256 150 10 5 1 2 2 15

5A 15 15 256 150 10 4 1 3 2 10-14 5B 15 15 256 150 10 3 1 4 2 8-9

Part 4:  138 of 65

Page 139: UMTS System Survey

UMTS  TimingUMTS  Timing

Page 140: UMTS System Survey

UMTS timingUMTS timing

Page 141: UMTS System Survey

Physical channels timingPhysical channels timing

Page 142: UMTS System Survey

Physical Channels summaryPhysical Channels summary

Page 143: UMTS System Survey

WCDMA Downlink Physical ChannelsWCDMA Downlink Physical Channels

• Common Downlink Physical Channels

• P‐CCPCH Primary Common Control Physical Channel‐ Broadcasts cell site information‐ Broadcasts cell SFN; Timing reference for all DL channels

• SCH Synchronization Channel‐ Fast Synch. codes 1 and 2; time‐multiplexed with P‐CCPCH

• S‐CCPCH Secondary Common Control Physical Channel‐ Transmits idle‐mode signaling and control information to 

UE’s• P‐CPICHCommon Pilot Channel • S‐CPICHSecondary Common Pilot Channel (for sectored cells)• PDSCH Physical Downlink Shared Channel

‐ Transmits high‐speed data to multiple users

• Dedicated Downlink Physical Channels• DPDCH Dedicated Downlink Physical Data Channel• DPCCH Dedicated Downlink Physical Control Channel

‐ Transmits connection‐mode signaling and control to UE’s

Page 144: UMTS System Survey

WCDMA Downlink Physical ChannelsWCDMA Downlink Physical Channels

• Downlink Indication ChannelsAICH (Acquisition Indicator Channel)

• Acknowledges that BS has acquired a UE Random Access attempt• Acknowledges that BS has acquired a UE Random Access attempt• (Echoes the UE’s Random Access signature)

PICH (Paging Indicator Channel)• Informs a UE to monitor the next paging frame

AP‐AICH (Access Preamble Acquisition Indicator Channel)• Acknowledges that BS has acquired a UE Packet Access attempt• (Echoes the UE’s Packet Access signature)

CD/CA ICH (C lli i D t ti /Ch l A i t I di t Ch l)CD/CA‐ICH (Collision Detection/Channel Assignment Indicator Channel)• Confirms that there is no ambiguity between UE in a Packet Access attempt• (Echoes the UE’s Packet Access Collision Detection signature)• Optionally provides available Packet channel assignments p y p g

CSICH (CPCH Status Indicator Channel)• Broadcasts status information regarding packet channel availability

Page 145: UMTS System Survey

WCDMA Uplink Physical ChannelsWCDMA Uplink Physical Channels

• Uplink Physical Channels

Common Uplink Physical Channels• PRACH Physical Random Access ChannelPRACH Physical Random Access Channel

‐ Used by UE to initiate access to BS

• PCPCH Physical Common Packet Channel‐ Used by UE to send connectionless packet data

Dedicated Uplink Physical Channels• DPDCH Dedicated Physical Data ChannelDPDCH Dedicated Physical Data Channel 

• DPCCH Dedicated Physical Control Channel‐ Transmits connection‐mode signaling and control to BS

Page 146: UMTS System Survey

WCDMA Downlink (FDD)WCDMA Downlink (FDD)

BCCHBroadcast Control Ch

BCHBroadcast Ch

P‐CCPCH(*)Primary Common Control Physical Ch

Logical Channels(Layers 3+)

Transport Channels(Layer 2)

Physical Channels(Layer 1)

CPICHCommon Pilot Channel

Null Data

Data Encoding

S/P

S/P

Cch 256,0

PSC

Sync Codes(*)Gain

Broadcast Control Ch.

PCCHPaging Control Ch.

CCCHCommon Control Ch.

Broadcast Ch.

PCHPaging Ch.

FACHForward Access Ch.

Primary Common Control Physical Ch.

S‐CCPCHSecondary Common Control Physical Ch.

SSCi

DPCH (Dedicated Physical Channel)CTCHCommon Traffic Ch.

Data Encoding

Data Encoding

Encoding

S/P

Cch

Cch 256,1

GS

GP ΣGain

Gain

SCH (Sync Channel)

DCCHDedicated Control Ch.

DPDCH (one or more per UE) Dedicated Physical Data Ch.

DownlinkRF Out

DPCH (Dedicated Physical Channel)One per UE

Common Traffic Ch.

S/P

Cell‐specificScrambling

Code

I+jQI/Q

IC Σ

Σ FilterGain

DTCHDedicated Traffic Ch. 1

DCHDedicated Ch.

Data Encoding

MUX

MUX

CCTrCHDCHDedicated Ch.

Data Encoding

DTCHDedicated Traffic Ch. N

DCHDedicated Ch.

DPCCH (one per UE)Dedicated Physical Control Ch.Pilot, TPC, TFCI bits

DSCHDownlink Shared Ch.

Data Encoding

Data Encoding

PDSCHPhysical Downlink Shared Channel

AICH

S/P

/Modulator

Q

Cch

Cch Σ

* Note regarding P‐CCPCH and SCH 

Sync Codes are transmitted only in bits 0‐255 of each timeslot;P‐CCPCH transmits only during the remaining bits of each timeslot

FilterGain

Gain

AICH (Acquisition Indicator Channel)

PICH (Paging Indicator Channel )

Access Indication data

Paging Indication bits

AP‐AICH(Access Preamble Indicator Channel )

Access Preamble Indication bits

CSICH (CPCH Status Indicator Channel )

CPCH Status Indication bits

S/P

S/P

S/P

S/P

C

Cch

Cch

Cch

P‐CCPCH transmits only during the remaining bits of each timeslot

Gain

Gain

Gain

GainCD/CA‐ICH (Collision Detection/Channel Assignment )

CPCH Status Indication bits

Cch

S/PCch Gain

Gain

Page 147: UMTS System Survey

WCDMA Uplink (FDD)WCDMA Uplink (FDD)

Logical Channels(Layers 3+)

Transport Channels(Layer 2)

Physical Channels(Layer 1)

Σ

CCCHCommon Control Ch.

RACHRandom Access Ch.

PRACHPhysical Random Access Ch.

Data Coding

Chd Gd

RACH Control Part

UplinkUE

ScramblingCode

Chc

DTCH (packet mode)Dedicated Traffic Ch.

CPCHCommon Packet Ch.

PCPCHPhysical Common Packet Ch.

Data Coding

Gc j

Σ

Chd Gd

RACH Control Part

RF OutCode

I+jQ I/QMod.

Q

IFilter

Filter

DPDCH #1Chd,1 Gd

Chc

Σ

Gc j

PCPCH Control Part

Σ

CCTrCH

ΣI

DPDCH #1Dedicated Physical Data Ch.

DPDCH #3 (optional)Dedicated Physical Data Ch.

DPDCH #5 (optional) Dedicated Physical Data Ch.

DPDCH #2 (optional)

Chd,3 Gd

Chd,5 Gd

Chd,2 Gd

Σ

DCCHDedicated Control Ch.

DTCHDedicated Traffic Ch. 1

DCHDedicated Ch.

Data Encoding M

UX

CCTrCH

DCHDedicated Ch.

Data Encoding

DPDCH #2 (optional) Dedicated Physical Data Ch.

DPDCH #4 (optional) Dedicated Physical Data Ch.

DPDCH #6 (optional) Dedicated Physical Data Ch.

ΣQ

Chd,4 Gd

Chd,6 Gd

Chc Gd

Σ

j

DTCHDedicated Traffic Ch. N

DCHDedicated Ch.

Data Encoding

Part 4:  147 of 65

DPCCHDedicated Physical Control Ch.Pilot, TPC, TFCI bits

c d

Page 148: UMTS System Survey

UMTS U Cell statusUMTS U Cell status

Page 149: UMTS System Survey

UMTS UMTS U Cell U Cell statusstatus

Cell_DCH

When we have a dedicated channel open for a subscriber (for example, if we are usingid ) th t b ib i i C ll DCH t t I thi t t th UE i divideo), we say that subscriber is in Cell_DCH state. In this state the UE is sendingmeasurement reports to the network, thus the system can control the dedicated bearerand perform handovers.

Cell_FACH

If the mobile is only sending small pieces of information for exampleIf the mobile is only sending small pieces of information, for exampleInternet based traffic or for signalling, then the RRC can be in a mode known as Cell_FACHand is different from the previous state as no dedicated channel is used. The network doesnot perform handovers as the mobile moves from one cell to another. The UE just informsthe network of its current location.

Page 150: UMTS System Survey

UMTS UMTS U Cell U Cell statusstatus

Cell_PCH

In addition to the Cell FACH, if the network finds that the bearer is not being used for a long_ , g gtime, it can move the connection to a Cell_PCH mode (Paging Channel), where the mobile isstill know to a cell level but can only be reached via the PCH..

URA_PCH

The final state is the URA_PCH. This state is similar to the Cell_PCH. But, instead ofmonitoring the connection on a cell level, it is now on a RNC level.

Page 151: UMTS System Survey

Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines

1. Before We Start

2. UMTS Introduction

4. UMTS Network Architecture.

3. WCDMA Concepts.

5. UMTS Air Interface Principles.

6. UMTS Procedures

7. UMTS services and applications

Page 152: UMTS System Survey

Data transmissionData transmission

Page 153: UMTS System Survey

The TDMA Transmitter

Sync. Bits

The Multiplexer allows various data channels to share the same timeslot.

Control/Signaling

Data

Error Protection

Timeslot

The timeslot selector allows multiple transmitters to share the same carrier frequency, by assigning a unique timeslot to each transmitter.

Data Multiplexer Transmit

G ti g

Filtering+

RF

RF Out

Selector

VocoderError

ProtectionGating RF

Modulation

User Data Channel 1

Error Protection

User Data Error Channel N Protection

Page 154: UMTS System Survey

The CDMA Transmitter

Sync. Bits

Orthogonal Code 1

Orthogonal Codes provide unique identification of each data channel

Control/Signaling

Data

Bits

Error Protection

Spread Spectrum (PN) Codes provide unique identification of each transmitter

Orthogonal Code 2

Filtering+

RF Out

Linear

S ti

Data

VocoderError

Protection

SpreadSpectrum

(PN or Gold)Code

Orthogonal Code 3

RF Modulation

Summation

User Data Channel 1

Error Protection

otect o

U 1

Orthogonal Code 4

Channel 1 Protection User 1

User 2

User 3

...Orthogonal

Code N

User Data Channel N

Error Protection

Frequency

Page 155: UMTS System Survey

Cellular CDMA Transmitter

Orthogon

Pre-coded data (bits)

Symbols Chips

Pulse

Data Channel

1

Spread Spectrum Code

(PN Code or Gold Code)

FEC Coding

Orthogonal Code 1

CRC Coding

Inter-leaving D/A SSC_QSSC_I

I I IShaping Filter

RF Out

D t

Linear

Summation

Orthogonal Code N

1:2Demux

Pulse Shaping Filter

I/Q Modulato

r

Complex Multiplie

r (I + jQ)

I

Q

I

Q

I

Q

Data Channel

N

CRC Coding

FEC Coding

Inter-leaving D/A

Allows for error

detection in the receiver

Allows for error

correction in the receiver

Improves error

correction in the

receiver

Gives a unique

identity to each data

stream

Maps digital bits to analog signals

Provides 2x higher data rate

(WCDMA,

Gives a unique identity to this

transmitter

Contains transmitte

d frequency spectrum

Allows both signals from 1:2 Demux to share

the same RF bandwidthreceiver receiver stream

0 → +1

1 → -1

(cdma2000 downlink)

spectrum bandwidth

Page 156: UMTS System Survey

Voice Coding

• VocodingHuman Voice:

‘ss’, ‘ff’, ‘sh’ … ~20% of time‘ah’, ‘v’, ‘mm’ , … ~80% of time

Voice Re-Synthesis at the Receiver

White Noise Generator

Noise

H(s)

SpeechVocoder

Pulse GeneratorΣ

Noiseparameters

Pitch Filter poles correspond to

SpeechOutput

H(s)

Transmitted Parameters8~12 kb/s typical,

parameters correspond to resonances of the

vocal tract

vs.64 kbps for log-PCM32 kbps for ADPCM

Page 157: UMTS System Survey

ACELP/AMR Voice Coding

A/D

Linear Predictive

Coding(LPC)

Voice, Tone Activity

Detectors

FilterCodebook

SpeechGenerator • Mode Indication bits

• Comfort Noise

• Tone EmulationΣ

(+)

(-)Filter

Codebook

Codebook Tone Emulation

• DTX IndicationΣ

PredictionIndex Perceptual

WeightingError

Analysis

VocoderOutput BitsMUX

Error

Benefits of Activity Detection:

1)

2)

Page 158: UMTS System Survey

CRC Coding

• Cyclic‐Redundancy Check (CRC) Coding

Identifies corrupted data

If there is an error, the receiver can request that data be re‐sent

For voice data errors, the vocoder discards any bad dataTransmitter

Checksum011010

Original Data 100101101010

CRC Generator

Original Data 100101101010

Receiver

If Checksums do not match Received Data Received Checksum

RF Transmission Path

CRC Generator

Re-Generated Checksum011011

If Checksums do not match, there is an error

Received Data 100101001010

Received Checksum 011010

Page 159: UMTS System Survey

CRC Algorithms

• CRC Algorithms

3GPP TS 25.212¶ 4.2.1.1

g– 0, 8, 12, 16, or 24 parity bits (determined by upper layers)pp y )

g(CRC24) D24 + D23 + D6 + D5 + D + 1• g(CRC24) = D24 + D23 + D6 + D5 + D + 1

• g(CRC16) = D16 + D12 + D5 + 1

• g(CRC12) = D12 + D11 + D3 + D2 + D + 1

• g(CRC8) = D8 + D7 + D4 + D3 + D + 1g( )

Page 160: UMTS System Survey

FEC Coding: The Convolutional Coder

Convolution Coding

Transmitter

Original Data 00011011...

FECGenerator

FEC Encoded data 1010011100110110...

Transmitter

RF Transmission Path

Original Data 00011011

Viterbi Decoder

Receiver

Page 161: UMTS System Survey

FEC Coding: Convolutional Coder

• Convolutional Coding: ExampleConvolutional Coding: ExampleX2k

clock

D DInput Data 1010...

MUX Coder Output

clock

X2k+1

R = 1/2 , k=2 Convolutional Coder

• For every input bit, there are two output bits

• The maximum time delay is 2 clock cycles

Page 162: UMTS System Survey
Page 163: UMTS System Survey

FEC Coding RulesFEC Coding Rules• FEC Coding

3GPP TS 25.212¶ 4.2.3

Transport Channel Coding Method Coder Rate

BCH Convolutional Coding 1/2

PCH Convolutional Coding 1/2

RACH Convolutional Coding 1/2 RACH Convolutional Coding 1/2

No Coding

Convolutional Coding 1/2 or 1/3 DCH, DSCH, CPCH FACH CPCH, FACH

Turbo Coding 1/3

Page 164: UMTS System Survey

WCDMA Convolutional Code Generators3GPP TS 25.212¶ 4.2.3.1

DD D D D D D DDataIn

Rate 1/2,  k=9 coder:

2:1MUX

DataOut

DD D D D D D DData

Rate 1/3 , k=9 coder:

In

3:13:1MUX

DataOut

Page 165: UMTS System Survey

WCDMA Turbo Code Generator

Xk3GPP TS 25.212¶ 4.2.3.2

D t I

Xk

Zk

Data InRate = X

MUX

Data Out3x input bits

Xk D D D

3x input bits + 12 Termination bits

TurboInterleaver

Z’k

D D D

X’k

At end of data block, both switches go “down” to provide 12‐bit Trellis Termination: [ x z x z x z x' z' x' z' x' z' ][ xK+1, zK+1, xK+2, zK+2, xK+3, zK+3, x K+1, z K+1, x K+2, z K+2, x K+3, z K+3 ]

Page 166: UMTS System Survey

Turbo Coding

T b C d• Turbo Codes

Outperform Convolution codes

Requires much more processing power; data packets may be decoded off‐line

Used for high‐bit rate data and packet data

Interleaving (time diversity) enhances error correction

DataDecodedData

D D

1

Turbo Encoder Turbo Decoder

Decoder #1

Encoder #1

MUX DE-MUXP1

P1

Interleaver

terlea

ver

nte

rlea

ver

Encoder #1

Encoder #2 Decoder #2P2 D

Interleaver

Int

De-

I

P2

Page 167: UMTS System Survey

Interleaving 1st level

Interleaving Matrix

Transmitter

Original Data Samples1 2 3 4 5 6 7 8 9 1 2 3

4 5 67 8 9

Interleaved Data Samples1 4 7 2 5 8 3 6 9

RF Transmission Path

Time

Am

plitu

de

De-Interleaving

Receiver

TimeTo Viterbi decoder

Interleaved Data Samples1 4 7 2 5 8 3 6 9

Errors Clustered

Interleaving Matrix

1 2 34 5 67 8 9

De-Interleaved Data Samples1 2 3 4 5 6 7 8 9

Errors Distributed

Page 168: UMTS System Survey

Interleaving 2nd level

I l i (‘K’ bl k i i (R C) bi h)• Interleaving (‘K’ blocks containing (R x C) bits each)

0, 1, 2, 3,  ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ , (RC ‐ 1)Before Interleaving

0C••(R‐1)C

1C+1••(R‐1)(C+1)

‐ ‐ ‐‐ ‐ ‐

mC+m••(R‐1)(C+m)

C‐12C‐1••RC‐1

‐ ‐ ‐‐ ‐ ‐

Write Data into MatrixRow‐wise

C0 C1 Cm CC‐1‐ ‐ ‐ ‐ ‐ ‐Permute Matrix

Columns

0C••(R 1)C

mC+m••(R 1)(C )

1C+1••(R 1)(C 1)

C‐12C‐1••RC 1

Read Data from MatrixColumn‐wise

(R‐1)C (R‐1)(C+m) (R‐1)(C+1) RC‐1

C0 Cm C1 CF‐1

After Interleaving 0, C, … , (R‐1)C , m, C+m, … (R‐1)(C+m) , … , 1, C+1 , (R‐1)(C+1), ..,  C‐1 , 2C‐1 , … RC‐1g

Page 169: UMTS System Survey

Rate Matching

• Rate Matching

– When coded data rates of services are incompatible, “Rate Matching” is used to equalize the data rates.

– Rate Matching may be performed by:

• Padding with extra bits

• Puncturing of bits using a pseudo‐random algorithmPuncturing of bits using a pseudo random algorithm

– For complete rate matching rules, see 3GPP TS25.212 ¶ 4.2.7

Page 170: UMTS System Survey

Rate matching

Page 171: UMTS System Survey

I/Q Modulation

• Graphical representation of an I/Q modulated signal Qsignal Q

( I = 1, Q = 1 )( I = -1, Q = 1 )

I

RF Carrier amplitude

RF Carrier phase angle

( I = -1, Q = -1 ) ( I = 1, Q = -1 )

1 Modulation Symbol represents 2 data bits

Modulation efficiency = 2 bits/symbol

Page 172: UMTS System Survey

I/Q Modulation

• I/Q (In‐phase/Quadrature) Modulation:  Definition

Two data streams are multiplied by a common carrier frequency, but p y q y,at phase offsets of 0 degrees (cosine)and 90 degrees (sine)

Data Stream #1 “ I ”+1

90o

I sin (2 π fRF t)

+ Q cos (2 π fRF t)

+1

-1

SUM

cos ( 2 π fRF t)

Q ( RF )

Data Stream #2 “ Q ”+1

-1

Page 173: UMTS System Survey

I/Q Modulation

• By multiplying by the sin and cosine at the receiver, the original I and Q data streams are recovered

Data Stream #1 “ I ”+1

90oSUM

I sin (2 π fRF t)

+ Q cos (2 π fRF t)

LPF-1

SUM

cos (2 π fRF t)

D t St #2 “ Q ”

LPF

Data Stream #2 “ Q ”+1

-1

Page 174: UMTS System Survey

The WCDMA Transmitter

BS code (DL) or

UE code (UL)

Spread Spectrum Code

(Gold Code)“Scrambling

Code”

OVSF CodeGenerator

RF

FIRFilterComplex

Spreading

“ChannelizationCode”Data

Channel Code

Data 011010

1….

Add CRC Bits

Add FEC Bits

I/Q Mod.

Out

FIR

Inter-leaver

p g(DL)

HPSKSpreading

(UL)

S/P

FIRFilter

Error Detection

Error Correction

Orthogonal Coding

SSMA Spreading,

PAPRReduction

SpectralContainment

RF Modulation

FadingResistance

Page 175: UMTS System Survey

Summary voice coding

Traffic data (122x2)

Add CRC bits 244T il 8

CRC16

T il 896

96CRC 16

Add CRC bits

Layer 3 Control data244

Traffic @ 12.2 kbps L3 Data @ 2.4 kbps

Conv. Coding R=1/3

360

Add Tail bits

804

260

Tail 8

360

112

Tail 8

1st interleaving

Add Tail bits

Conv. Coding R=1/3

1st interleaving804

402

110 110 110 110Rate Matching

402Frame Segmentation

#1a   490 #2a   490 #1b   490 #2b   490

Frame Segmentation 90 90 90 90

6002nd  interleaving 600 600 600

490 110

slot segmentation 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40

490 110 490 110 490 110

Radio frame FN=4N+1 Radio frame FN=4N+2 Radio frame FN=4N+3Radio frame FN=4N

slot segmentation

30 ksps DPDCH

40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40

600 bits (300 symbols) 600 bits (300 symbols) 600 bits (300 symbols) 600 bits (300 symbols)

Page 176: UMTS System Survey

Summary data coding

Traffic data (3840x2)

3840

CRC16

96

96CRC 16

Layer 3 Control data3840

Traffic @ 384 kbps L3 Data @ 2.4 kbps

3840

CRC16

3840

Add CRC bits Add CRC bits

Turbo Coding R=1/3

36023160

11568

7712

3840

Terminationbits

360

112

Tail 896

1st interleaving

Conv. Coding R=1/3

1st interleaving

3840

Concatenate Concatenate

Add CRC bits Add CRC bits

12 11568 12

360

9525

23160

11580

75 75 75 75Rate matching

1st interleaving

Frame Segmentation

1st interleaving

11580

9525 9525 9525

Frame Segmentation 90 90 90 90

9600

9525 75

2nd  interleaving 9600 9600 9600

9525 75 9525 75 9525 75

slot segmentation 640 640 640 640 640 640 640 640 640 640 640 640

Radio frame FN=4N+1 Radio frame FN=4N+2 Radio frame FN=4N+3Radio frame FN=4N

slot segmentation

480 ksps DPDCH 9600 bits (4800 symb.) 9600 bits (4800 symb.) 9600 bits (4800 symb.) 9600 bits (4800 symb.)

640 640 640 640 640 640 640 640 640 640 640 640

Page 177: UMTS System Survey

Summary

Page 178: UMTS System Survey

S h i tiSynchronization

Page 179: UMTS System Survey

Acquisition and Synchronization

• Physical Layer Procedures1) UE Acquisition and Synchronization P-CCPCH1) UE Acquisition and Synchronization

Initiate Cell Synchronization

(PSC + SSC + BCH)

UE Monitors Primary SCH code, detects peak in matched filter output

Slot Synchronization Determined ------>

UE Monitors Secondary SCH code, detects SCG and frame start time offset

Frame Synchronization and Code Group Determined ------>

UE Determines Scrambling Code by correlating all possible codes in group

Scrambling Code Determined ------>

UE Monitors and decodes BCH data

Cell Synchronization Complete

Page 180: UMTS System Survey

Synchronization Codes

Synchronization Codes (PSC, SSC)

Broadcast by BS• First 256 chips of every SCH time slot

3GPP TS 25.213 ¶ 5.2.3

Allows UE to achieve fast synchronization in an asynchronous system

Primary Synchronization Code (PSC)• Fixed 256‐chip sequence with base period of 16 chips

• Provides fast positive indication of a WCDMA system

• Allows fast asynchronous slot synchronization

Secondary Synchronization Codes (SSC)• A set of 16 codes, each 256 bits long

• Codes are arranged into one of 64 unique permutations

• Specific arrangement of SSC codes provide UE with frame timing, BS “code group”

Page 181: UMTS System Survey

Primary Synchronization Code

• Primary Synchronization Code (PSC)l t 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

3GPP TS 25.213 ¶ 5.2.3

let a = <1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1>

PSC(1...256) = < a, a, a, -a, -a, a, -a, -a, a, a, a, -a, a, -a, a, a >

Note: PSC is transmitted “Clear” (Without scrambling)

2304 Chips256 ChipsSCH BCH

Broadcast Data (18 bits)SSCi

pp

PSC

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1 Frame = 15 slots = 10 mSec

Page 182: UMTS System Survey

Slot Synchronization

• Slot Synchronization using Primary Synchronization Code

3GPP TS 25.214 Annex C

BCH Data

PSC[1]

BCH Data

PSC[2]

BCH Data

PSC[3]

BCH Data

PSC[4]

BCH Data

PSC[15]

Matched Filter(Matched to PSC)

10 mSec Frame (15 slots x 666.666 uSec)

P-CCPCH

(PSC)

MatchedFilterOutput

time

Page 183: UMTS System Survey

Secondary Synchronization Code Group

3GPP TS 25.213 ¶ 5.2.3

• 16 Fixed 256‐bit Codes; Codes arranged into one of 64 patterns

slot number Scrambling Code Group

#1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15

G 1 1 1 2 8 9 10 15 8 10 16 2 7 15 7 16

SSC1 SSC2

SSCi

Group 1 1 1 2 8 9 10 15 8 10 16 2 7 15 7 16

Group 2 1 1 5 16 7 3 14 16 3 10 5 12 14 12 10

Group 3 1 2 1 15 5 5 12 16 6 11 2 16 11 15 12

• • •

SSC2 SSC3 SSC4 SSC5 SSC6 SSC1 SSC15• • •

• • •

Group 62 9 10 13 10 11 15 15 9 16 12 14 13 16 14 11

Group 63 9 11 12 15 12 9 13 13 11 14 10 16 15 14 16

Group 64 9 12 10 15 13 14 9 14 15 11 11 13 12 16 10

SSC6 SSC7 SSC8 SSC9 SSC10

1 15

Group 64 9 12 10 15 13 14 9 14 15 11 11 13 12 16 10

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1 Frame = 15 slots = 10 mSec

SSC10 SSC11 SSC12 SSC13 SSC

Note:

The SSC patterns positively identify one and only one of the 64 Scrambling Code Groups.

This is possible because no cyclic shift of any SSC is equivalent to any cyclic shift of any other SSC.

1 Frame 15 slots 10 mSecSSC14 SSC15 SSC16

Page 184: UMTS System Survey

Frame Synchronization

• Frame Synchronization using Secondary Synchronization Code

BCH Data

SSC[1]

BCH Data

SSC[2]

BCH Data

SSC[3]

BCH Data

SSC[4]

BCH Data

SSC[15]

10 mSec Frame (15 slots x 666.666 uSec)

Matched Filter

Matched to SSC code group pattern

SSC[2]

SSC[3]

SSC[4]

SSC[1]

SSC[6]

SSC[7]

SSC[8]

SSC[5]

SSC[10]

SSC[11]

SSC[12]

SSC[9]

SSC[14]

SSC[15]

SSC[13]

code g oup patte

MatchedFilterOutput

SSC Code Group Pattern provides

• Frame Synchronization

• Positive ID of Scrambling Code Group

Remember no cyclic shift of any SSC is equal to any other SSCRemember, no cyclic shift of any SSC is equal to any other SSC

time

Page 185: UMTS System Survey

Call SetupCall Setup

Page 186: UMTS System Survey

PRACH procedure

Page 187: UMTS System Survey

Random Access

• Random Access Attempt and AICH Indication3GPP TS 25.211 ¶ 7.3

AICH

RACH

PPre-

bl

Pre-amble

RACH

message part

4096 chips(1.066 msec)

Pre-amble

amble

A

message part(UE Identification)UE

NoInd.

NoInd.

Acq.Ind.BS

Page 188: UMTS System Survey

Random Access Procedure

• Prior to initiating a Random Access attempt, the UE receives:

The preamble scrambling code for this cell

The available random access signatures and set of available RACH sub-channels

The available spreading factors for the message part

The message length (10 ms or 20 ms)

Initial preamble power parameter

The power-ramping factor Power Ramp Step [integer > 0]The power-ramping factor Power Ramp Step [integer > 0]

The parameter Preamble Retrans Max [integer > 0]

The AICH transmission timing parameter [0 or 1]

The power offset ΔPp-m between preamble and the message part.

Transport Format parameters

Page 189: UMTS System Survey
Page 190: UMTS System Survey
Page 191: UMTS System Survey

Random Access Preamble Signatures

Random Access Preamble Signature Symbols Signature P0 P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 P13 P14 P15

3GPP TS 25.213 ¶ 4.3.3.3

Signature P0 P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 P13 P14 P15

0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 2 1 1 -1 -1 1 1 -1 -1 1 1 -1 -1 1 1 -1 -1 3 1 -1 -1 1 1 -1 -1 1 1 -1 -1 1 1 -1 -1 1 4 1 1 1 1 -1 -1 -1 -1 1 1 1 1 -1 -1 -1 -1 5 1 -1 1 -1 -1 1 -1 1 1 -1 1 -1 -1 1 -1 1 6 1 1 -1 -1 -1 -1 1 1 1 1 -1 -1 -1 -1 1 1 7 1 -1 -1 1 -1 1 1 -1 1 -1 -1 1 -1 1 1 -1 8 1 1 1 1 1 1 1 1 -1 -1 -1 -1 -1 -1 -1 -1 9 1 -1 1 -1 1 -1 1 -1 -1 1 -1 1 -1 1 -1 1 10 1 1 -1 -1 1 1 -1 -1 -1 -1 1 1 -1 -1 1 1 11 1 -1 -1 1 1 -1 -1 1 -1 1 1 -1 -1 1 1 -1 12 1 1 1 1 -1 -1 -1 -1 -1 -1 -1 -1 1 1 1 1 13 1 -1 1 -1 -1 1 -1 1 -1 1 -1 1 1 -1 1 -1 14 1 1 -1 -1 -1 -1 1 1 -1 -1 1 1 1 1 -1 -1 15 1 -1 -1 1 -1 1 1 -1 -1 1 1 -1 1 -1 -1 1 15 1 -1 -1 1 -1 1 1 -1 -1 1 1 -1 1 -1 -1 1

• Preamble codes are 16-long Orthogonal Codes.

• Preamble = [ P0, P1, … P15 ] repeated 256 times (4096 chips total).

• Preamble codes help the BS distinguish between UE making simultaneous Random Access Attempts.

Page 192: UMTS System Survey

Random Access Scrambling Codes

• Random Access Preamble Scrambling Codes

Preamble Scrambling Code is a 4096‐chip segment of a 225‐long Gold CodePreamble Scrambling Code is a 4096‐chip segment of a 2 ‐long Gold Code

The UE targets one BS by using the BS’s indicated preamble scrambling code

“All UE accessing this cell shall use Random Access Preamble Spreading Code

n2 ”

“All UE accessing this cell shall use Random Access Preamble Spreading Code

n1 ” n2n1

Page 193: UMTS System Survey

Random Access

• Physical Layer Procedures

2) UE Requests System Access and Registration P-CCPCH

(PSC + SSC + BCH)

Cell Synchronization Complete

UE Reads Random Access parameters from BS;Calculates Random Access probe power

Initiate Random Access Attempt; Respond to Authentication challenge

When system Registration is complete, UE enters Idle mode

Page 194: UMTS System Survey

Paging procedure

Page 195: UMTS System Survey

Paging procedure

Page 196: UMTS System Survey

Admission ControlAdmission Control

Page 197: UMTS System Survey

Admission Control

The most important − and the most difficult − to control in WCDMA is theinterference occurring in the radio path.

One of the basic criteria for planning is to define the acceptable interferenceOne of the basic criteria for planning is to define the acceptable interferencelevel, with which the network is expected to function correctly.

This planning based on the actual signals the UE transmit set practical limitsf th U i t f itfor the Uu interface capacity.

A value called SIR (Signal-to-Interference Ratio) is used in this context.

In the BTS receiver, the interference and the signal must have a certain levelof power difference in order to extract one signal (code) out from the othersignals using the same carrier.

Every UE having a bearer active through this cell “consumes” a part of theSIR. The cell is used up to its maximum level when the BTS receiver is notable to extract the signal from the carrier

Page 198: UMTS System Survey

The main task of admission control is to estimate whether a new call can haveaccess to the system without sacrificing the bearer requirements of existing calls.

The AC algorithm should predict the load of the cell if the new call isThe AC algorithm should predict the load of the cell if the new call isadmitted.

Based on the admission control, the Radio Network Controller(RNC) either grants or rejects the access.

When applying mathematics, it can be found out that the Signal-to-InterferenceRatio (SIR) or Interference Margin has direct relationship with the cell load If weRatio (SIR) or Interference Margin has direct relationship with the cell load. If weexpress the cell load with a Load_Factor (10 % load gives value 0.1) and markthe Interference Margin with I, it leads to the following equation:

⎟⎟⎠

⎞⎜⎜⎝

⎛−

⋅=FactorLoad

LogI_1

110

Page 199: UMTS System Survey

Admission Control

In te r fe re n c e M a rg in (d B ) a n d L o a d F a c to r

2 0

2 5(d

B)

5

1 0

1 5

2 0

erfe

renc

e M

argi

n (

00 0 .1 0 .2 0 .3 0 .4 0 .5 0 .6 0 .7 0 .8 0 .9 1

L o a d F a c to r

Inte

Based on the graph it is fairly easy to indicate that when the cell loadexceeds 70 %, the interference in that cell will be very difficult to control.

This is h the WCDMA radio net ork is normall dimensioned ithThis is why the WCDMA radio network is normally dimensioned withexpected capacity equivalent to Load Factor value 0.5 (50 %). This valuehas a safety margin in it and the network will behave as expected.

Page 200: UMTS System Survey

Admission Control Factors

Transmission 

availability

Codes available

Node B

Processing Capabilities

Admission

Control

SoftPower 

recourses

Soft handover & upgrades 

Margins

Interference limitation

Page 201: UMTS System Survey

Cell breathing conceptCell breathing conceptCell breathing conceptCell breathing concept

C ll b thi i CDMA h d b th lti l i t f d d l th t d ff b t d itCell breathing is a CDMA phenomena caused by the multiple access interference, and models the trade-off between coverage and capacity

Desired Signal

InterferingSignals

Max TX powerMax TX power

Page 202: UMTS System Survey

Cell breathing conceptCell breathing conceptCell breathing conceptCell breathing concept

C ll b thi i CDMA h d b th lti l i t f d d l th t d ff b t d itCell breathing is a CDMA phenomena caused by the multiple access interference, and models the trade-off between coverage and capacity

Desired Signal

InterferingSignals

( f )( f ) b fb fNoise rise (interference margin) Noise rise (interference margin) αα number of usersnumber of users

Page 203: UMTS System Survey

H dHandover

Page 204: UMTS System Survey

WCDMA Handover Types

2 Categories of Handovers exist in WCDMA based on connection status

Soft Handover :(Make before Break)

H d H d (B k b f M k )Hard Handover: (Break before Make)

Each Category further divided into types depending on the action taken in the Handover commandin the Handover command

Page 205: UMTS System Survey

WCDMA Handover Types

Hard Handover : can by divided into three typesInter Frequency HandoverUE change WCDMA carrier frequencyUE change WCDMA carrier frequency

Inter Radio Access Technology Handover - (I-RAT) Handover -UE change WCDMA carrier to GSM network or vice versag

Inter Radio Access Technology Cell Change - (I-RAT) Cell Change -UE change WCDMA carrier to GPRS network or vice versa

In all Hard Handover types Traffic and control channels are disconnected thenIn all Hard Handover types Traffic and control channels are disconnected then reconnected – Break Before Make –

Page 206: UMTS System Survey

WCDMA Handover Types

Soft Handover : can by divided into two typesSoft Handover

UE connected to more than one RBSs at same time – Theoretically up to number of RAKE Receiver fingers, practically by Active set

Softer HandoverSofter HandoverUE connected to another cell within the same RBS

UE has the ability to add, remove and replace radio links for different cells on same radio frequencycells on same radio frequency

Continuous data flow is maintained as data is combined at RAKE receiver

Soft Handover degrade system capacity where UE is connected to more than RBS in same time

Page 207: UMTS System Survey

Soft Handover 

BTSBTSBTS

Soft Handover

Frequencyf1

Frequencyf1

Soft Handover

Soft handover is performed between two cells belonging to different Node Bsbut not necessarily to the same RNC. The source and target cell of the softhandover has the same frequency.

Page 208: UMTS System Survey

CDMA Soft HandoverCDMA Soft Handover

Monitor Neighbor BS Pilots Add Destination BS Drop Originating BS

– One finger of the RAKE receiver is constantly scanning neighboring Pilot g y g g gChannels.

– When a neighboring Pilot Channel reaches the t_add threshold, the new BS is added to the active set

– When the original Base Station reaches the t_drop threshold, originating Base Station is dropped from the active set

Page 209: UMTS System Survey

WCDMA Soft Handover

• Each cell uses a different Scrambling Code• Each cell has an independent time reference• CPICH and System Frame timing between cells is arbitrary

D ti ti BSDestination BSOriginating BS SC5 SC6

SC1SC4SC7 SC8 SC4SC7 SC8

Page 210: UMTS System Survey

WCDMA Handover Scenarios

Core Network

3GPP TS 25.832

RNS RNS

Iu Iu

RNC RNCIur

Iub IubIub Iub←UTRAN →

Node B Node B Node B Node B

Inter‐Node( d f )

Intra‐Node( f )

Inter‐RNS( f i h(Hard or Soft) (Softer)(Soft with Iur;Hard with no Iur)

Page 211: UMTS System Survey

The WCDMA Soft Handover Problem...

• WCDMA Base Stations have Asynchronous timing references• IS‐95/cdma2000 BS’s are synchronized to GPS!

Data 2TFCIData 1 TPC Pilot

0.666 msec DPCCH/DPDCH slot

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

10 msec DPCCH/DPDCH frame

CPICH 2CPICH 2CPICH 2

CPICH 1CPICH 1CPICH 1

CPICH 2

CPICH 1

10 msecframe

BS 1

BS 2DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH

DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH

Toffset

Page 212: UMTS System Survey

WCDMA Soft Handover

• Soft Handover Initiation

(2)UE measures

(3)UE Reports measurements

(1)UTRAN informs UE

(4)UTRAN decidesUE measures 

CPICH power and time delay from adjacent cells

UE Reports measurements to UTRAN

UTRAN informs UE of neighboring cell information

UTRAN decides the handover strategy

BS 2

CPICH 2CPICH 2CPICH 2

CPICH 1CPICH 1CPICH 1

DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH

CPICH 2

CPICH 1

DPCCH/DPDCH

10 msecframe

BS 1

BS 2

DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH

ToffsetUE Reports Toffsetto UTRANto UTRAN

UTRAN

Page 213: UMTS System Survey

Softer Handover 

BTSSector 1f1

Sector 2f1Multipath Signal

through Sector 1

Sector 3f1

through Sector 1

Multipath Signalthrough Sector 3

f1g

Softer Handover

In softer handover the UE transmits and receives signals via two air interfacechannel concurrently, one for each sector separately. Both channels are received aty, p ythe same Node B by maximal ratio combining RAKE processing.

Page 214: UMTS System Survey

WCDMA Soft Handover

S f H d E i(6)UE Rake Receiver Synchronizes to BS2 

(7)UE in soft handover with BS1 and BS2 

(5)UTRAN Commands BS2 to adjust DPCH timing by 

(8)When BS2 sufficiently strong, drop BS1.

• Soft Handover Execution

DPCCH/DPDCH DPCCH/DPDCH’sToffset (Handover complete)

CPICH 2CPICH 2CPICH 2CPICH 2BS 2

CPICH 1CPICH 1CPICH 1

DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH

CPICH 1

DPCCH/DPDCH

10 msecframe

BS 1 DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH

Toffset

ToffsetUE Reports Toffsetto UTRAN

UTRAN

UTRAN Commands BS2to adjust DPCH timingby Offset

Page 215: UMTS System Survey

RAKE Reception Concept

Interference in WCDMA plays greater rule than thermal noise

Multi paths reception for same signal can cause fading phenomenon

Delay between multi paths is typically 1-2 μSec in urban areas and 20 μSec in Hilly areas

WCDMA chip time is 0.26 μSec

WCDMA system uses RAKE receiver to overcome fading problem

Page 216: UMTS System Survey

Rake Reception Concept

Rake Receiver consists of number of reception fingers

Dedicated finger assigned to do measurements on NeighbourDedicated finger assigned to do measurements on Neighbour Node-Bs

Each finger locks on same signal but for different delays – different pathspaths –

Delay resolution within finger is ± ½ chip, total delay within receiver 30 μSec

The alignment of the fingers done by correlating the decoded CPICHwith an internally generated version at receiver. Applying suitable amount of delay at each finger

After Alignment a Combined signal will be generated – constructive addition –

Page 217: UMTS System Survey

The RAKE ReceiverThe RAKE Receiver

• CDMA Mobile Station RAKE Receiver Architecture– Each finger tracks a single multipath reflection

• Also be used to track other base station’s signal during soft handoverAlso be used to track other base stations signal during soft handover– One finger used as a “Searcher” to identify other base stations

Finger #1

Finger #2

Sum ofindividual multipath components

Combinercomponents

Finger #N

Searcher Finger

Power measurement of Neighboring Base Stations

Page 218: UMTS System Survey

The RAKE Receiver ArchitectureThe RAKE Receiver Architecture

CDMA RAKE Receiver Architecture

“I” PN(2 f

CarrierFrequencyTrackingLoop Rake Receiver

“Finger”

BPF LPF

I PNCode(+1/-1)

ΣIntegrate

over‘SF’ chips

De-Interleave

Data

Viterbi/Turbo

Decoder

DecodedOutputBits

bit rate = chip rate / SF

cos(2πfIFt)

ΣDI/Q

Demod

“Q” PNCode

(+1/-1)

Orthogonal

Code(+1/-1)

p

CRCVerification

cos(2πfRFt)

Ti i

Dd

ErrorIndication

PilotOrthogonal

Code(all zeros)

TimingAdj. Correlator

Other Rake Receiver Finger

Page 219: UMTS System Survey

Hard/Inter‐Frequency Handover

BTSBTS

Hard Handover

Frequencyf1

Frequencyf2

Hard Handover

Hard Handover functionality is same like GSM

Page 220: UMTS System Survey

Inter‐System Handover

BTSBTS

WCDMA GSM900/1800

Inter-System Handover

Inter Radio Access Technology Handover ‐ (I‐RAT) Handover ‐UE change WCDMA carrier to GSM network or vice versa

Inter Radio Access Technology Cell Change ‐ (I‐RAT) Cell Change ‐UE change WCDMA carrier to GPRS network or vice versa

Page 221: UMTS System Survey

Handover Control (HC)

BTSBTSBTSSector 1

f1Sector 2

f1Multipath Signalthrough Sector 1

Soft

Frequencyf1

Frequencyf1

Sector 3f1

Multipath Signalthrough Sector 3

Soft Handover Softer HandoverBTSBTS

Inter-System HandoverBTSBTS

WCDMA GSM900/1800

HandoverBTS

Frequencyf1

Frequencyf2

Hardf1 f2

Page 222: UMTS System Survey

Inter‐Frequency Handover

• Inter‐frequency Handover

– To allow inter‐frequency measurements, data is compressed in time so that some of the 10 mSecframe is available for measurements.

• 8 to 14 slots per frame may be used

– Data compression can be accomplished by:

• Decreasing the Spreading Factor by 2:1 – Increases Data Rate so bits get through twice as fast!– Increases Data Rate so bits get through twice as fast!

• Puncturing bits– weakens FEC coding

• Higher layer scheduling– Reduces available timeslots for user traffic

Page 223: UMTS System Survey

Compressed Mode Operation3GPP TS 25.212 ¶ 4.4.3

• 1 to 7 slots per frame diverted for hard handover processesThe complete TFCI word must be transmitted every frame, even in Compressed Mode.Compressed Mode Slot formats (A,B) contain higher proportion of TFCI bits per slot compared with normal slots

1 2 3 4 5 6 7 8 9 1 1 1 1 1 11 2 3 4 51 1 1 1 1 6

10 mSec Frames (15 slots)

Normal Operation

per slot compared with normal slots.

1 2 3 4 5 6 7 8 9 10

11

12

13

14

151 2 3 4 51

112

13

14

15

6

Compressed‐Mode; single‐frame method

1 2 3 4 5 11

12

13

14

151 2 3 4 51

112

13

14

15

6

Transmission Gap

1 2 3 4 5 6 7 8 9 10

11

12

4 511

12

13

14

15

6

Compressed‐Mode; double‐frame method

Transmission Gap

Page 224: UMTS System Survey

Handover to/from GSM

• Handover to/from GSM

– GSM handover is an explicit requirement in WCDMA

F ilit t d b lit f lti f t t– Facilitated by commonality of multi‐frame structures

12 WCDMA 10 mSec Frames (120 ms)

1 2 3 4 5 6 7 8 9 10 11 12

T T T T T T T T T T T S T T T T T T T T T T T T T I

GSM 26‐frame TCH multiframe (120 ms)

T = Traffic FrameS = SACCH FrameI = Idle Frame

Page 225: UMTS System Survey

P C lPower Control

Page 226: UMTS System Survey

WCDMA Power Control Importance

Power is a shared resource in WCDMA system

Po er tili ation is so important toPower utilization is so important toIncrease system capacityDecrease overall interference in the system (Overcome near far problem effect)far problem effect)

WCDMA system provide fast power control procedure

1500 power order command / Sec = 1 power order command / Slot

3 Loops interact to provide power control procedure

Page 227: UMTS System Survey

WCDMA Power Control Importance

All WCDMA users operating on same carrier are sources for interference

Amount of interference of all users on a Channel provide the limit of system capacity on that channel

i.e.) each channel has its minimum accepted SIR (Signal to Interference Ratio)

Having UEs in a different position from Node-B also create the near- far problem,

i.e.) Near UEs – suffer from relatively low path loss - can block the decoded signal from far UEs

Page 228: UMTS System Survey

WCDMA Power Control Importance

UE C suffers less path loss the B and finally A

Page 229: UMTS System Survey

WCDMA Power Control Importance

All Mobiles A, B and C suffers same path lossMobile A decoded signal suffers relatively little interference

All Mobiles A, B and C suffers different path lossMobile A decoded signal blocked due high interference

Page 230: UMTS System Survey

WCDMA Power Control procedure

WCDMA power control procedure consists of 3 LoopsOpen-loopOuter-loop pInner-loop

Increase Transmit Power

by 1 dBOpen-Loop Power Control

Measure

Transmit Access Preamble

Access Acknowledged?

by 1 dBNoCompute

Initial Transmit

Power

received powerfrom BS

Read BS transmit power from Broadcast

ChannelYes

MS BeginsUplink TCH

Transmission

Outer-Loop (slow) Power Control Inner-Loop (fast) Power Control

BLER Acceptable

?

Raise RxPower Target

No Received power

> target?

Increase MS Transmit Power

by 1 dB

D MS

No

Transmission ?Lower Rx

Power TargetYes

> target? Decrease MS Transmit Power

by 1 dBYes

Page 231: UMTS System Survey

CDMA Power ControlCDMA Power Control

P(SIR‐Target,UL)

Inner loopInner loop

DL‐TPC UL‐TPC RNCUL‐Outer loop

P(SIR‐Target, DL)

SIR‐Target,UL

SIR‐Error,UL

Open loopBLER‐Measured,DL

DL‐Outer loop

BLER = Block Error Rate

SIR = Signal to Interference Ratio

TPC = Transmit Power Control

P(Startvalue)SIR‐Target,DL

Page 232: UMTS System Survey

Course OutlinesCourse Outlines

1. Before We Start

2. UMTS Introduction

4. UMTS Network Architecture.

3. WCDMA Concepts.

5. UMTS Air Interface Principles.

6. UMTS Procedures

7. UMTS services and applications

Page 233: UMTS System Survey

Topics

• Person‐to‐Person Circuit Switched ServicesPerson to Person Circuit Switched Services

• Person‐to‐Person Packet Switched Services

C S i• Content‐to‐Person Services

• Location Based Services

• Fixed Mobile Convergence

Page 234: UMTS System Survey

Person‐to‐Person Circuit Switched Services

• AMR Speech Service11.4 or 22.8 Kbps

(3.65 – 10.6 Kbps) (4.75 – 12.2 Kbps)

Error Control Bits Voice Bits

• Video Telephony

CircuitS i h dCircuit

S i h dSwitchedNetworkSwitchedNetwork

Packet SwitchedNetwork

Page 235: UMTS System Survey

AMR Speech Service : Introduction

• AMR provides a set of codec's fitting in FR and HR physical channels, providing variable tradeoff between error protection and speech quality,...

• And an algorithm to change between codec's (Link Adaptation, or Codec Mode Adaptation)Adaptation)

• An algorithm to change between FR and HR codec's (Channel Mode Adaptation)

20

25

bit/s

) Channel codingSpeech coding Error Protection (FER)

10

15

l bit-

rate

(kb

0

5

FR12.2

FR10.2

FR7.95

FR 7.4 FR 6.7 FR 5.9 FR5.15

FR4.75

HR7.95

HR 7.4 HR 6.7 HR 5.9 HR5.15

HR4.75

Cha

nne

Speech Quality (MOS)

AMR codec mode

Page 236: UMTS System Survey

Video Telephony

• constant bit rate, small delay variation and continuous bit flow

• Lower BER requirements comparing to speech servicesq p g p• Available for both circuit switched and packet switched 

networks

CircuitSwitchedNetwork

CircuitSwitchedNetwork

Packet SwitchedNetwork

Page 237: UMTS System Survey

Person‐to‐Person Packet Switched Services

• Images and Multimedia

• Push‐to‐Talk over Cellular (PoC)

• Voice over IP (VoIP)

• Real Time Video Sharing (RTVS)Real Time Video Sharing (RTVS)

• Multiplayer Games

camera

file

Page 238: UMTS System Survey

Multimedia Messaging Service (1/2)

MultimediaMessagingService

music

SMS

SmartMessaging& EMS

video

textonly

Text, simple graphics,ringing tones

stills

etc.

Page 239: UMTS System Survey

Multimedia Messaging Service (2/2)

Standardised „envelope“: encapsulated messages

variable size

messages

Content:Minimum set of supported media types recommended:• text• audio• audio• images• video 

addressesMSISDN or URL

Page 240: UMTS System Survey

Push‐to‐Talk over Cellular (PoC)

Telephone communication

• Communication the mainPush to Talk communication• Virtual connection exists throughout theCommunication the main 

activity 

• Capacity is used for the whole duration of the 

Virtual connection exists throughout the session = possibility to talk at any instance, staying informed

• Capacity is used only when someone talks, one way

call, two wayy

• Near real‐time service

Page 241: UMTS System Survey

PoC is a Voice over IP serviceover a GPRS network

UMTS N t kUMTS NetworkIP Packets

IP Packets

IP PacketsIP Packets

IP PacketsIP Packets

IP Packets

IP PacketsIP Packets

IP PacketsIP Packets

IP PacketsIP Packets

Client 2

Client 1POC application servers• PoC Call Processor

PoC Register

Client 3

• PoC Register

Page 242: UMTS System Survey

Voice over IP (VoIP)

• Provide rich call (real time communication session between two or more persons)session between two or more persons)

• Complement with 2‐way video, streaming video, images, content sharing, gaming etc.

Page 243: UMTS System Survey

Multiplayer Games

Page 244: UMTS System Survey

Content‐to‐person Services

• Browsing

• Audio and Video Streaming

• Content Download

Page 245: UMTS System Survey

Browsing

Page 246: UMTS System Survey

Audio and Video Streaming

Streaming FeaturesStreaming Features– Supports both audio and video streaming

– Supports VCR‐like controls, namely PLAY, PAUSE & STOP

Pl /P /R t i hil l i– Play/Pause/Resume streaming while playing

– Stop streaming midway

– Abort streaming session

Page 247: UMTS System Survey

IP Multimedia Services (IMS)

• Enable the usage of multimedia services built on Internet applications and protocolson Internet applications and protocols

• Enable IP connectivity between users

Utili S i I iti ti P t l (SIP) t• Utilize Session Initiation Protocol (SIP) to establish peer‐to‐peer sessions

Page 248: UMTS System Survey

Location based services

L ti b d i t d i

BTSGMLC

RNC

HLR3G-SGSN

• Location can be used in smart devices(for example in a car). 

BTS

3G-MSC

Location Server

ApplicationsBSC

SMLC

• There are different ways to locate a

BTS

Location ManagementToolNetwork Management

/Planning System

• There are different ways to locate a subscriber. The most common will use BTS measurements.

• Location based information can be used for different applications. 

Page 249: UMTS System Survey

Location services ‐Methods

• Cell ID based methodP iti i ith th h l f th i b t ti– Positioning with the help of the serving base station

• GPS ‐ Global Positioning System– Accurate but limitations indoors and during bad weather conditions– Accurate, but limitations indoors and during bad weather conditions

– Terminals may be equipped with GPS receivers.

Page 250: UMTS System Survey

Location Based Service examples