Cdma and Umts Basics

W-CDMA ExplainedW-CDMA Explained

Presented by Dr Tony VernonPresented by Dr Tony Vernon

Course ContentCourse Content

�� Section 1Section 1-- IntroductionIntroduction

�� Section 2Section 2-- Codes and their characteristicsCodes and their characteristics

�� Section 3Section 3-- CDMA implementationCDMA implementation

�� Section 4Section 4-- CDMA in operationCDMA in operation

�� Section 5 Section 5 –– UMTS TechnologyUMTS Technology

�� Section 6 Section 6 –– UMTS Air InterfaceUMTS Air Interface

�� Section 7 Section 7 -- UTRANUTRAN

Course ObjectivesCourse Objectives

�� Understand the process and benefits of CDMAUnderstand the process and benefits of CDMA

�� Understand the application of direct sequence CDMAUnderstand the application of direct sequence CDMA

�� Understand synchronisation requirements Understand synchronisation requirements

�� Understand modulation requirements and techniquesUnderstand modulation requirements and techniques

�� Appreciate the different code types available and their propertiAppreciate the different code types available and their propertieses

�� Understand how codes may be applied in CDMA systemsUnderstand how codes may be applied in CDMA systems

�� Understand the use of complex spreadingUnderstand the use of complex spreading

�� Understand the importance, application and principles of rake reUnderstand the importance, application and principles of rake receiverceiver

�� Understand the importance of power control in CDMA systemsUnderstand the importance of power control in CDMA systems

�� Appreciate the impact of cell breathing effectsAppreciate the impact of cell breathing effects

CDMA ExplainedCDMA Explained

Section 1Section 1

IntroductionIntroduction

Multiple Access SchemesMultiple Access Schemes

User 1

User 2

User 3

User 4

FDMA

Time

Frequency

TS0 TS1 TS2 TS3 TS0 TS1 TS2 TS3TDMATime

Frequency

User 1 & User 2 & User 3 & User 4CDMATime

Frequency

CDMA PrincipleCDMA Principle

FrequencyBB

Code 1Code 1 CDMACDMA

FrequencyBB

FrequencyWW FrequencyWWCDMA

Code 2Code 2

Frequency

WW

CDMACDMA--1 1 ((~ ~ CDMA)CDMA)

Code 1Code 1

GGpp= W/B

Shannon’s Equation & CDMAShannon’s Equation & CDMA

C= W x log2 (1+S/N)

C= Channel capacityW= Channel bandwidthS/N= Energy per bit/ Noise power

CDMA Systems ClassificationCDMA Systems Classification

CDMA

Hybrid CDMAPure CDMA

Direct

Sequence

Frequency

Hopping

Time

Hopping

Fast FH Slow FHNarrowband Wideband

DS/ FH

DS/ TH

FH/ TH

DS/ FH/ TH

TDMA/ CDMA

MC-CDMA

MT-CDMA

Frequency Hopping CDMAFrequency Hopping CDMA

Power

Frequency

Time

Direct Sequence SpreadingDirect Sequence Spreading

0 1 0

Chip

SymbolData

Code

Data x Code

Spreading Factor (SF)= Chip rate / Symbol rate

DS-CDMA Transmitter/ ReceiverDS-CDMA Transmitter/ Receiver

XWideband Modulator

CarrierGenerator

CodeGenerator

Wideband Demodulator

CarrierGenerator

De-spreading

CodeGenerator

Code Sync/Tracking

Transmitter block diagram Receiver block diagram

FrequencyFrequencyCarrier FrequencyCarrier Frequency

Chip rateChip rate


Symbol rateSymbol rate

2 x Symbol rate2 x Symbol rate

DS- Frequency DomainDS- Frequency Domain

Gp = Chip rate/ Symbol rate

Direct Sequence De-spreadingDirect Sequence De-spreading

0 1 0

Chip

Symbol

De-Spread Data

Local Code

Received Data

Hybrid System: DS/ (Fast) FHHybrid System: DS/ (Fast) FH

PN-Code 1

PN-Code 2

PN-Code 3

PN-Code 4

PN-Code 5

Frequency

Time

Data bit period

Hybrid System: MC-CMDAHybrid System: MC-CMDA

OR

S/P

QAM modulator

ΣΣΣΣX X

CM Cos(2πf+φM)t

X X

C1 Cos(2πf)t +

QAM modulator

S1

SN

To antenna

Input

S/P

QAM modulator

ΣΣΣΣ

X X

C1…q Cos(2πf)t

QAM modulator

S1

SN

X X

C1…q Cos(2πfN)t

To antennaInput

Separating users- example- DS spreadingSeparating users- example- DS spreading

A Data

A Code

Data x Code

B Data

B Code

A + B

(A + B)x A Code

Local A Code

Integrator Output

Comparator

Output

Data x Code

© Bcomms Ltd 2000

CDMA and Cell Reuse CDMA and Cell Reuse

Cell 4Cell 6

Cell 7

Cell 5

Cell 1

Cell 3

Cell 2

Cell 4Cell 6

Cell 7

Cell 5

Cell 1

Cell 3

Cell 2

Cell 4Cell 6

Cell 7

Cell 5

Cell 1

Cell 3

Cell 2

Cluster

FDMA or TDMA cellular system

Cell 1Cell 1

Cell 1

Cell 1

Cell 1

Cell 1

Cell 1

Re-use distance Re-use distance

CDMA cellular system

Cell Capacity ConsiderationCell Capacity Consideration

X ~ X ~ GpGp

EbEb/No/No

InterferenceInterference

X ~ X ~ GpGp

[[Eb/No]xEb/No]x 1.61.6

Interference Limited- FactorsInterference Limited- Factors

Activity factorEb

Noeff

=1

No

Eb

+2

3G(M-1) 1+K)( αα

Intercell vs intracell interference

Energy per bit

To

Noise density

No of users per cell

Processing Gain

Received energy per bit

Noise Density

Bandwidth ConsiderationsBandwidth Considerations

�� Base_band bandwidthBase_band bandwidth

�� Average (n~GAverage (n~Gpp/n/n00))�� Statistical approximationStatistical approximation

�� Law of large numberLaw of large number

�� MultipathMultipath�� No. Components increase with No. Components increase with

bandwidthbandwidth

�� Less energy per componentLess energy per component

�� Receiver complexityReceiver complexity

�� Spectrum allocation/ operating Spectrum allocation/ operating conditionsconditions

�� OthersOthers…………

Performance Loss

0

20

40

60

80

100

0 500 1000 1500

Processing Gain

Eff

icie

nc

y

CDMA BenefitsCDMA Benefits

�� Increased capacityIncreased capacity

�� Good call qualityGood call quality

�� Digital systemDigital system

�� No break during softNo break during soft--handoverhandover

�� Fading rejection due to large bandwidthFading rejection due to large bandwidth

�� PrivacyPrivacy

�� Power control Power control �� battery savingbattery saving

�� FlexibilityFlexibility

�� System planningSystem planning

�� Bandwidth on demandBandwidth on demand

Spread Spectrum Application: WLANSpread Spectrum Application: WLAN

Independent Basic

Service Set(IBSS)

Station 3

Station 1

Station 2

IEE 802.11 : DSSS and FHSSIEE 802.11 : DSSS and FHSS

Characteristics FHSS DSSS

Data Rate (Air Interface) Up to 3Mbps Up to 11Mbps

Net Data Throughput Up to 2.4Mbps Up to 5.5Mbps

Number of co-locatedcells / systems

Maximum 26 per

hopping set. There are 3 sets of 26

Maximum 3. Channels 1,7 & 13

Modulation per carrierRF 2.4 GHz

2-level Gaussian FSK (1Mbps)4-level Gaussian FSK (2Mbps)

Differential BPSK(1Mbps)Differential QPSK(2Mbps)

Spread Spectrum Application: GPSSpread Spectrum Application: GPS

�� 24 satellites/ 6 orbits24 satellites/ 6 orbits

�� Altitude: 20.200 kmAltitude: 20.200 km

�� Repeat pattern= 1 dayRepeat pattern= 1 day

�� User determines position/ User determines position/

time from a minimum of 3 time from a minimum of 3

satellitessatellites

�� Time received/ Time of Time received/ Time of

ArrivalArrival

�� Local error corrected by Local error corrected by

44thth satellitesatellite

~20.200 km

orbit

CDMA and GPSCDMA and GPS

Coarse Acquisition Code

Satellite PRN ID

NAV Data

+

+Precise Code

Precise Code(encryption)

+

Modulation

50 bps

Modulation

L1 carrier

L1/ L2 carriers

L2 signal

L1 signal

1.023 Mchip/s

Processing Gain= 30 dB

10.23 Mchip/sSmall receiver

Spread Spectrum Application:

Cellular- e.g. IS-95

Spread Spectrum Application:

Cellular- e.g. IS-95

Reverse(Uplink) link

Forward (Downlink) link

CDMA- User multiplexing

CDMA- Cell identification

CDMA- Channel separation


Section 2Section 2

Codes and their CharacteristicsCodes and their Characteristics

Code CharacteristicsCode Characteristics

[Data1 x Code1 +Data2 x Code2] x Code1shift(n)

+

Data2 x Code2 x Code1shift(n)


Code ClassificationsCode Classifications

�� Code LengthCode Length�� Short CodeShort Code

�� Long CodeLong Code

�� Code FamilyCode Family�� PseudoPseudo--Random CodesRandom Codes

�� Combinational CodesCombinational Codes

�� Orthogonal CodesOrthogonal Codes

1 0 0 1

1 0 0 1

Code Length

Code Length

Pseudo-random Code GenerationPseudo-random Code Generation

1 2 3 4

Maximum Length Sequence

1 2 3 4Input

Input

0 1 1 1 1

1 0 1 1 10 1 0 1 1

1 0 1 0 1

1 1 0 1 0

0 1 1 0 1

0 0 1 1 01 0 0 1 1

0 1 0 0 1

0 0 1 0 0

0 0 0 1 0

1 0 0 0 11 1 0 0 0

1 1 1 0 0

1 1 1 1 0

0 1 1 1 1

1 0 1 1 1

Output

24-1= 15

�� Balance PropertyBalance Property

�� RunRun--length Distributionlength Distribution

�� ““PerfectPerfect”” AutocorrelationAutocorrelation

�� ““BadBad”” XcorrelationXcorrelation

�� Limited number of sequencesLimited number of sequences

�� Not usable for securityNot usable for security

Pseudo-random Code: Autocorrelation (1)Pseudo-random Code: Autocorrelation (1)

Original Sequence: 1 1 1 1 0 1 0 1 1 0 0 1 0 0 0

Shifted by 1 chip: 0 1 1 1 1 0 1 0 1 1 0 0 1 0 0

Similarity x �� x x x x �x � x x �� Σ = 7-8= -1


Shifted by 2 chips: 0 0 1 1 1 1 0 1 0 1 1 0 0 1 0

Similarity x x � �x �� x x x x �x � Σ = 7-8= -1


Shifted by 15 chips: 1 1 1 1 0 1 0 1 1 0 0 1 0 0 0

Similarity �� Σ = 15

Pseudo-random Code: Autocorrelation (2)Pseudo-random Code: Autocorrelation (2)

Autocorrelation function

-2

0

2

4

6

8

10

12

14

16

0 10 20 30 40

Delay

Au

toco

rre

lati

on

Pseudo-random Code: Cross-correlation (1)Pseudo-random Code: Cross-correlation (1)

First Sequence: 1 1 1 1 0 1 0 1 1 0 0 1 0 0 0

Second Sequence: 1 1 1 1 0 0 0 1 0 0 1 1 0 1 0

Similarity � ��x � � x � x � � x � Σ = 11- 4= 7

First Sequence: 1 1 1 1 0 1 0 1 1 0 0 1 0 0 0

Second Sequence shifted: 0 1 1 1 1 0 0 0 1 0 0 1 1 0 1

Similarity x � �� x x �x �� x � x Σ = 9- 6= 3

First Sequence: 1 1 1 1 0 1 0 1 1 0 0 1 0 0 0

Second Sequence: 1 1 1 0 0 0 1 0 0 1 1 0 1 0 1

Similarity �� x � x x x x x x x x � x Σ = 5- 10= -5

Pseudo-random Code: Cross-correlation (2)Pseudo-random Code: Cross-correlation (2)

Cross correlation

-6

-4

-2

0

2

4

6

81 4 7

10

13

16

19

22

25

28

31

34

Relative delay

Cro

ss c

orr

ela

tio

n

Pseudo-random Code: Code SetsPseudo-random Code: Code Sets

Register length Sequence length No. m-sequences

23

45678

91011

37

153163

127255

51110232047

22

2661816

4860

176

Limited number of sequences

Gold Code GenerationGold Code Generation

�� Large number of codesLarge number of codes

�� ““ControlledControlled”” ((PredictablePredictable) ) XcorrelationXcorrelation

�� UniformUniform

�� BoundedBounded

1 2 3 4 5

1 2 3 4 5

Gold Code Sequence

Initial value = “all 1”

Different initial values = Different Gold code Sequences

Gold Code: AutocorrelationGold Code: Autocorrelation

Autocorrelation function

-2

0

2

4

6

8

10

12

14

16

0 10 20 30 40

Delay

Au

toco

rre

lati

on

We are definitively loosing here!..

BUT….

Preferred pairsPreferred pairs�� CrossCross--correlation: correlation:

�� 3 values 3 values

�� Auto and crossAuto and cross--

correlationcorrelation

�� UniformUniform

�� BoundedBounded

Hadamard MatrixHadamard Matrix

General Formula: Hn=Hn-1 Hn-1

Hn-1 - Hn-1

H0 = [1]

H1 =1 1

1 -1

H2 =

1 1

1 -1

1 1

1 -11 11 -1

-1 -1-1 1

OVSF Code GenerationOVSF Code Generation

1

1 1

1 0

1 1 1 1

1 1 0 0

1 0 1 0

1 0 0 1

1 1 1 1 1 1 1 1

1 1 1 1 0 0 0 0

1 1 0 0 1 1 0 0

1 1 0 0 0 0 1 1

1 0 1 0 1 0 1 0

1 0 1 0 0 1 0 1

1 0 0 1 1 0 0 1

1 0 0 1 0 1 1 0

�� OrthogonalOrthogonal (I.e (I.e

XcorrelationXcorrelation = 0)= 0)

�� Must be synchronousMust be synchronous

�� SF= code lengthSF= code length

�� DonDon’’t spread equallyt spread equally

�� Code AllocationCode Allocation

�� Consumes all downConsumes all down--

stream codestream code

�� Consumes all upConsumes all up--

stream codestream code

OVSF Codes in OperationOVSF Codes in Operation

Data A

Code A (SF4)

Data A x Code A

Data B

Code B (SF4)

Data B x Code B

Sum

Sum x Code A

1 -1 -1 1

11-1-1 11-1-1 11-1-1 11-1-1

11-1-1 -1-111 -1-111 11-1-1

1 1 -1 -1

1-1-11 1-1-11 1-1-11 1-1-11

1-1-11 1-1-11 -111-1 -111-1

2 0-2 0 0-2 0 2 -2 0 2 0 0 2 0-2

2 0 2 0 0-2 0-2 -2 0-2 0 0 2 0 2

After Integration

1 -1 -1 1

Generalised Hierarchical Golay SequenceGeneralised Hierarchical Golay Sequence

A= Pattern(1,-1) of length k

X= {Repeat or invert A, n times}

Cm= X x hnk, m’

hnk, m = row m’ of Hadamard(nk)

A=<1,1,-1,1>

X= <A,-A>

(X= <1,1,-1,1,-1,-1,1,1>)

C0 = X x H8,0

H8,0 = <1,1,1,1,1,1,1,1>

C0 = <1,1,-1,1,-1,-1,1,1>

C1 = X x H8,4

H8,4 = <1,-1,1,-1,1,-1,1,-1>

C1 = <1,-1,-1,-1,-1,1,1,-1>

Code requirements in cellular systemsCode requirements in cellular systems

�� ChannelisationChannelisation

�� Good Good xcorrelationxcorrelation

(orthogonal codes)(orthogonal codes)

�� User/ Cell identificationUser/ Cell identification�� Good compromise between Good compromise between

autoauto-- & cross& cross--correlationcorrelation

�� Good Spreading Good Spreading

�� White Noise likeWhite Noise like

Σ Σ

Channelisation Channelisation

Cell identification

(Scrambling)

Codes in Cellular System: IS-95 (DL)Codes in Cellular System: IS-95 (DL)

x

x

Long pseudo-random Sequence (242-1)

Long code mask(user n/ p)

x

Decimated

64:1

x

Walsh code n/p

Coded Data Traffic (user n)/ paging 19.2 Kbps

IQ

modΣ

Pilot (0 kbps) x

Walsh code 0

~RF carrier

Coded sync data19.2 Kbps x

Walsh code 32

I-Pilot

pseudo-random Sequence (215-1)

Q-Pilot

pseudo-random

Sequence (215-1)

1.2288 Mcps

PN-offset

PN-offset

Codes in Cellular System: IS-95 (UL)Codes in Cellular System: IS-95 (UL)

x

xLong pseudo-random

Sequence (242-1)

Long code mask

(from ESN)

xCoded Data Traffic

28.8 KbpsIQ

Offset

mod

Walsh codes

~RF carrier

I-Pilot

pseudo-random Sequence (215-1)

Q-Pilot

pseudo-random

Sequence (215-1)

1.2288 Mcps

PN-offset

PN-offset

64-ary orthogonal

modulator

307.2 Kb/s

Codes in Cellular System: UTRA (DL)Codes in Cellular System: UTRA (DL)

S/P

x

x

OVSF(SF= 4, 8, 16, 32, 64, 128, 256, 512)

ScramblingGold code

(length 218 –1)

3.84 Mcps

3.84 Mcps

IQ

mod

~RF carrier

Any Downlink Physical Channel

(except SCH)

Σ

x

x....x

Gi

Gj

Gk

Σx

Gp

x

Gs

P-SCH

code

S-SCH

code

Data +

Control

(Generalised Hierarchical Golay)

Codes in Cellular System: UTRA (UL)Codes in Cellular System: UTRA (UL)

x

OVSF(SF= 256)

Scrambling

Gold code

(length 225 –1)Or

S(2) code

(length 256)

3.84 Mcps

3.84 Mcps

IQ

mod

~RF carrier

x

GdData

x

GcControl

OVSF(SF= 4, 8, 16, 32, 64, 128, 256)

x


Section 3Section 3

CDMA ImplementationCDMA Implementation

Modulation and Spreading (1)Modulation and Spreading (1)

x

Cos (ωt)

x

Sin (ωt)

+S/P

I-branch

Q-branch

Input data

To Transmission

QPSK modulation

x

x

Spreading

Discontinuous TransmissionDiscontinuous Transmission

Data present Data presentData absent

Data present Data presentData absent

User information Control information

EMC (uplink)

IQ/Code multiplexing

Time multiplexing

IQ/ MultiplexingIQ/ Multiplexing

x

Cos (ωt)

x

Sin (ωt)

+

I-branch

Q-branch

user data

To Transmission

x

x

Spreading

control data

Spreading

Complex ScramblingComplex Scrambling

x

x

x x

+

+

PN1

PN1

PN2

+

-

+

+

PN2

I-branch

Q-branch

Equivalent to

[I+jQ][PN1 +jPN2]

Receiver Building BocksReceiver Building Bocks

�� Coherent IQ demodulatorCoherent IQ demodulator

�� DeDe--spreading functionspreading function

�� IQ to data mappingIQ to data mapping

�� Synchronisation loopsSynchronisation loops

�� IFIF--carriercarrier

�� Chip frequencyChip frequency

Wideband Demodulator

CarrierGenerator

De-spreadingIQ

CodeGenerator

Code Sync/Tracking

PLL

Synchronisation loops

PN Decorrelator: Matched FilterPN Decorrelator: Matched Filter

InputTcTc

TcTcTcTc

TcTc

xh0

xh1

xh2

xhn-2

xhn-1

+Output

Delay Line

Output

Time

“1”

“0”

PN Decorrelator: Active CorrelatorPN Decorrelator: Active Correlator

∫period

dt0

(.)xThresholddetector

Thresholddetector

Code

generatorCode

generator

Input output

IntegrateDump

Output

Time

“1”

“0”

Code SynchronisationCode Synchronisation

�� Time uncertaintyTime uncertainty

�� Phase difference (carrier, code Phase difference (carrier, code sequencesequence-- uplink)uplink)

�� Propagation delayPropagation delay

�� Relative clock shiftsRelative clock shifts

�� Frequency uncertaintyFrequency uncertainty

�� Relative velocityRelative velocity-- Doppler shift)Doppler shift)

�� Two stepsTwo steps

�� AcquisitionAcquisition--

�� sliding sliding correlatorcorrelator

�� or or

�� matched filter (short codes)matched filter (short codes)

�� TrackingTracking

∫period

dt0

(.)xThresholddetector

Thresholddetector

Search controlSearch controlChip clock

generatorChip clock

generator

Code

generatorCode

generator

Input

Sliding Correlator

Tracking PhaseTracking Phase

Time

0 Tc 2Tc-Tc-2Tc

Late Early

Autocorrelation

Delay

0Tc/2

-Tc/2

Late

Early

Autocorrelation

Tracking point

Tracking ImplementationTracking Implementation

∫period

dt0

(.)

x

Threshold

detectorThreshold

detector

Code

generatorCode

generator

Input

Delay +Tc/2

Delay +Tc/2

∫period

dt0

(.)

∫period

dt0

(.)

LatchLatch

LatchLatch

-

+

Chip clock GeneratorChip clock Generator

Early

Late

Delay -Tc/2

Delay -Tc/2

x

xPrecise Decoded output

Synchronisation: Pilot SequencesSynchronisation: Pilot Sequences

Uplink link synchronisation

Downlink link synchronisation

Pilot or preamble

Pilot channel • Common channel

• Channel associated

Radio ImpairmentsRadio Impairments

�� FadingFading

�� InterInter--SymbolSymbol--InterferenceInterference

Multi-path

‘Rake’ Receiver‘Rake’ Receiver

RF/ IF

Downconverter

Analog-to-Digital

Correlator # 1

Correlator # 2

Correlator # n

.....

Searcher

......... Co

mb

ine

r

To Decoder

Controller

Code 1

Sw

itch m

atr

ix

Code 2

Code k

Code 1


Section 4Section 4

CDMA in OperationCDMA in Operation

CDMA System Requirements-Power Control


8 Km8 Km

80 m80 m

Distance Ratio: 8,000/80 = 100Distance Ratio: 8,000/80 = 100

Jamming Margin Required= Jamming Margin Required= 40 dB40 dB

CDMA System Requirements-

Fast Power Control


Fast Power Control

Power UPPower UP

(Building shadow)(Building shadow)

Power DownPower Down

(and QUICK!(and QUICK!…… or or

degradation of other degradation of other

mobilemobile’’s signal)s signal)

CDMA System Requirements-Soft Handover


Base Station ABase Station A

Base Station BBase Station B

Power ControlPower Control


Power ControlPower ControlPower ControlPower Control




Types of HandoverTypes of Handover

Softer HandoverNode

B

Node

B

Soft Handover

F1

F1

�� Soft HandoverSoft Handover

�� Hard handoverHard handover

�� InterInter--frequency/ Intrafrequency/ Intra--systemsystem

�� InterInter--systemsystem

RNC

Cell A

Handover RegionHandover Region

Cell B

Cell A

Soft handover

(Cell A & B)

Cell B

Two-cell scenario

Cell A Cell B

Cell C

Three-cell scenario

Handover: Reporting Events Examples

Handover: Reporting Events Examples

Measurement

Quality

Time

Possible Reporting Events

Cell A- Pilot

Cell B-Pilot

Cell C- Pilot

Cell D- Pilot

Note: Cell D is not yet in active set

Reporting rangeA

B

CD

E

Soft & Softer HandoverSoft & Softer Handover

�� Best instantaneous uplink frameBest instantaneous uplink frame

�� ““Make before breakMake before break”” connection connection �� No break No break

in communicationsin communications

�� No ping pong effectNo ping pong effect

�� Reduced no. of dropped callsReduced no. of dropped calls

�� Hardware decoder required at more Base Hardware decoder required at more Base

stationsstations

�� More interference created in the downlink/ More interference created in the downlink/

more code used per usermore code used per user

Soft handover region?

Cell BreathingCell Breathing

Becomes out of range

Inter-frequency HandoverInter-frequency Handover

Frequency F1

Frequency F1

Frequency F1

Frequency F2

Rake receiver doesn't see F2

Compressed ModeCompressed Mode

�� PurposePurpose

�� Measurements at Measurements at ≠≠ frequencyfrequency

�� Reduction of Processing GainReduction of Processing Gain

�� CDMA: SF/2 orCDMA: SF/2 or

�� Coding: puncturingCoding: puncturing

�� Power increasedPower increased

Transmission gap for inter-

frequency measurements

Data Transmission Data Transmission

Site Selection Diversity TransmitSite Selection Diversity Transmit

Cell C

Cell ACell B

A Primary cell

Data + control

(Power Control)

(Power Ctl)

Data+ control

B Primary cell

(Power Control)

(Power Ctl)

Benefit of SSDTRef: TS 25.922

Benefit of SSDTRef: TS 25.922

Syste

m load [

kbps/ M

Hz/c

ell

0

100

200

300

400

5.4 11 110

Mobile Speed [km/h]

w/ UE's space

diversity

w/o UE's space

diversity

SSDT

SSDT

Conventional TPC

Conventional TPC

55224.3

Closed Loop Transmit DiversityClosed Loop Transmit Diversity

Spreading/Scrambling

Data + control

(Downlink)

x

x

w1

w2 Σ

Σ

Pilot Channel #1 Antenna 1

Antenna 2

Decode

Tx

Tx

Rx

Rx

Weight GenerationPilot Channel #2

Diversity SummaryDiversity Summary

�� Frequency diversityFrequency diversity

�� Spatial diversitySpatial diversity

�� Path diversityPath diversity

�� Time diversityTime diversity

Fade:

12.5 dB

400 kHz

5MHz channel

Overall drop

~ 12.5 x 400/ 5000 = 1dB

Open Loop Power ControlOpen Loop Power Control

Initial

Preamble Power

Time

Output power

Time-out

Power_step

Time-out

Power_step

Preamble

acknowledgement

User Data(e.g. initial access)

Power Control SummaryPower Control Summary

�� Open LoopOpen Loop

�� Close LoopClose Loop

�� UplinkUplink

�� DownlinkDownlink

Node B

UE Transmits Preamble at computed Power

BCCH

Node B

SIRest> SIRtarget ?∆dB

Up/ Down


Up/ Down

BCCH

Antenna ConsiderationsAntenna Considerations

3-sectors, 90°beamwidth 6-sectors, 60°beamwidth

Multi-User Detection (MUD)Multi-User Detection (MUD)

FrequencyBB

FrequencyBB

FrequencyBB

FrequencyWW

CDMACDMACode 1Code 1

CDMACDMA

Code 2Code 2CDMACDMA

Code 3Code 3

WW

WW

WW

Noise estimation


Section 5Section 5

UMTS Technology OverviewUMTS Technology Overview

Asynchronous Transfer ModeAsynchronous Transfer Mode

�� Switching technologySwitching technology�� HardwareHardware…………..but also software..but also software

�� Statistical multiplexingStatistical multiplexing

�� Packet mode transmissionPacket mode transmission�� Cell= 53 octetsCell= 53 octets

�� Header carries virtual path/ virtual circuit identitiesHeader carries virtual path/ virtual circuit identities

�� Connection orientedConnection oriented�� PrePre--established virtual circuitsestablished virtual circuits

VPI & VCI HEC Payload (48 octets)

ATM Layers & Service ClassesATM Layers & Service Classes

Physical Layer

ATM Layer

ATM Adaptation Layer

Higher Layer Higher Layer

Control Plane User Plane

Management Plane

ATM Layers

A B C DClasses

User Bit Rate

End-to-End

Synchronisation

Connection Oriented ?

Constant Variable

Required Not Required

NoYes

Service Classes

AAL-1

AAL-2

AAL-3/4AAL-5 (data)

VP and VC SwitchingVP and VC Switching

VPI = 4 VPI = 5

VCI= 1

VCI= 2

VCI= 10

VCI= 12

VP Switch

VC Switch

VPI = 1

VCI= 3

VCI= 4

VCI= 1

VCI= 12VPI = 3

VPI = 2

VCI= 3 VCI= 4 VCI= 1

VCI= 12

Physical

LayerPhysical

Layer

ATM LayerATM Layer

Peer-to-peer protocolsPeer-to-peer protocols

AALAAL

Upper

Layer

Protocols

Upper

Layer

Protocols

Physical

LayerPhysical

Layer

ATM LayerATM Layer

Physical

LayerPhysical

Layer

ATM LayerATM Layer

Physical

LayerPhysical

Layer

ATM LayerATM Layer

AALAAL

Upper

Layer

Protocols

Upper

Layer

Protocols

UNI NNI UNI

CDMA PrincipleCDMA Principle

FrequencyBB

Code 1Code 1 CDMACDMA

FrequencyBB

FrequencyWW FrequencyWWCDMA

Code 2Code 2

Frequency

WW

CDMACDMA--1 1 ((~ ~ CDMA)CDMA)

Code 1Code 1

GGpp= W/B

Direct Sequence SpreadingDirect Sequence Spreading

0 1 0

Chip

SymbolData

Code

Data x Code

Spreading Factor (SF)= Symbol rate/ Chip rate


Chip rateChip rate


Symbol rateSymbol rate

2 x Symbol rate2 x Symbol rate

DS- Frequency DomainDS- Frequency Domain

Gp = Chip rate/ Symbol rate

Direct Sequence De-SpreadingDirect Sequence De-Spreading

0 1 0

Chip

Symbol

De-Spread Data

Local Code

Received Data

Cell Capacity ConsiderationCell Capacity Consideration

X ~ X ~ GpGp

EbEb/No/No

InterferenceInterference

X ~ X ~ GpGp

[[Eb/No]xEb/No]x 1.61.6

Separating users- exampleSeparating users- example

A Data

A Code

Data x Code

B Data

B Code

A + B

(A + B)x A Code

Local A Code

Integrator Output

Comparator

Output

Data x Code

© Bcomms Ltd 2000

Code CharacteristicsCode Characteristics

[Data1 x Code1 +Data2 x Code2] x Code1shift(n)

+



Code ClassificationsCode Classifications

�� Code LengthCode Length�� Short CodeShort Code

�� Long CodeLong Code

�� Code FamilyCode Family�� PseudoPseudo--Random CodesRandom Codes

�� Combinational CodesCombinational Codes

�� Orthogonal CodesOrthogonal Codes

1 0 0 1

1 0 0 1

Code Length

Code Length

Code RequirementsCode Requirements

�� ChannelisationChannelisation

�� Good Good xcorrelationxcorrelation

(orthogonal codes)(orthogonal codes)

�� User/ Cell identificationUser/ Cell identification�� Good compromise between Good compromise between

autoauto-- & cross& cross--correlationcorrelation

�� Good Spreading Good Spreading

�� White Noise likeWhite Noise like

Σ Σ

Channelisation Channelisation

Cell identification

(Scrambling)

Uplink/ Downlink Scrambling CodesUplink/ Downlink Scrambling Codes

Cell CCell A Cell B

User codeCell B code

Cell A code

User code

Cell A code

User code

Cell C code



20 Km20 Km

200 m200 m

Distance Ratio: 20/0.2 = 100Distance Ratio: 20/0.2 = 100

Jamming Margin Required= Jamming Margin Required= 40 dB40 dB


Fast Power Control


Fast Power Control

Power UPPower UP

(Building shadow)(Building shadow)

Power DownPower Down

(and QUICK!(and QUICK!…… or or

degradation of other degradation of other

mobilemobile’’s signal)s signal)



Base Station ABase Station A

Base Station BBase Station B



Power ControlPower ControlPower ControlPower Control




Types of HandoverTypes of Handover

Node

B

Node

B

F1

F1

�� Soft HandoverSoft Handover

�� Hard handoverHard handover

�� InterInter--frequency/ Intrafrequency/ Intra--systemsystem

�� InterInter--systemsystem

RNC

Soft HandoverSofter Handover

Radio ImpairmentsRadio Impairments

�� FadingFading

�� InterInter--SymbolSymbol--InterferenceInterference

Multi-path

Rake ReceiverRake Receiver

RF/ IF

Downconverter

Analog-to-Digital

Correlator # 1

Correlator # 2

Correlator # n

.....

Searcher

......... Co

mb

ine

r

To Decoder

Controller

Code 1

Sw

itch m

atr

ix

Code 2

Code k

Code 1

Cell BreathingCell Breathing

Becomes out of range

Multi-User Detection (MUD)Multi-User Detection (MUD)

FrequencyBB

FrequencyBB

FrequencyBB

FrequencyWW

CDMACDMACode 1Code 1

CDMACDMA

Code 2Code 2CDMACDMA

Code 3Code 3

WW

WW

WW

Noise estimation


Section 6Section 6

UMTS Air Interface ProtocolsUMTS Air Interface Protocols

Access Stratum- Protocol ArchitectureAccess Stratum- Protocol Architecture

Physical layer

Physical channels

Transport channels

Medium Access Control (MAC)

Logical channels

Radio Link Control (RLC)

PDCP BMC

Radio Resource Control(RRC)

Layer 1

Layer 2

Layer 3


Physical

Control

MAC

Control

RLC

Control

Channel TypesChannel Types

Logical ChannelsLogical Channels

Control Channels

Traffic Channels

Control PlaneControl Plane

User PlaneUser Plane

Ma

pp

ing/

Ma

pp

ing/

Mu

ltip

lexin

gM

ultip

lexin

g Common

Channels

Dedicated

Channels

Transport ChannelsTransport Channels

Mu

ltip

lexin

g/

Mu

ltip

lexin

g/

Sp

littin

gS

plit

tin

g ............

Physical ChannelsPhysical Channels

ChannelisationChannelisation

OVSF= Orthogonal Variable Spreading FactorOVSF= Orthogonal Variable Spreading Factor

ΣΣ

ScramblingScrambling

Logical Channels-R99Logical Channels-R99

Broadcast

ControlChannel(BCCH)

Paging

ControlChannel(PCCH)

Common

ControlChannel(CCCH)

Dedicated

ControlChannel(DCCH)

Shared Channel

ControlChannel(SHCCH)

Dedicated

TrafficChannel(DTCH)

Common

TrafficChannel(CTCH)

Transport Channels- R99Transport Channels- R99

Broadcast

Channel(BCH)

Paging

Channel(PCH)

Random

AccessChannel(RACH)

Forward

AccessChannel(FACH)

Downlink

SharedChannel(DSCH)

Dedicated

Channel(DCH)

Uplink

SharedChannel(USCH)

Common

PacketChannel(CPCH)

(TDD only) (FDD only)

Logical to Transport Channels

(FDD)

Logical to Transport Channels

(FDD)�� Broadcast Control Channel Broadcast Control Channel

(BCCH)(BCCH)

�� Broadcast Channel (BCH)Broadcast Channel (BCH)

�� Forward Access Channel (FACH)Forward Access Channel (FACH)

�� Paging Control Channel (PCCH)Paging Control Channel (PCCH) �� Paging Channel (PCH)Paging Channel (PCH)

�� Common Control Channel Common Control Channel (CCCH)(CCCH)

�� Random Access channel (RACH)Random Access channel (RACH)


�� Common Traffic Channel (CTCH)Common Traffic Channel (CTCH) �� Forward Access Channel (FACH)Forward Access Channel (FACH)

�� Dedicated Traffic Channel Dedicated Traffic Channel (DTCH)(DTCH)

&&

�� Dedicated Control Channel Dedicated Control Channel (DCCH)(DCCH)


�� Dedicated Channel (DCH)Dedicated Channel (DCH)

�� Downlink Shared Channel (DSCH)Downlink Shared Channel (DSCH)

�� Random Access channel (RACH)Random Access channel (RACH)

�� Common Packet Channel (CPCH)Common Packet Channel (CPCH)

MAC- Physical Layer Data Exchange

(example)

MAC- Physical Layer Data Exchange

(example)

10 ms

Time

Transport channel #1, transmission time interval = 20ms



Uplink Physical ChannelsUplink Physical Channels

Physical RandomAccess Channel

(PRACH)

Physical CommonPacket Channel

(PCPCH)

Physical UplinkShared Channel

(PUSCH)

Dedicated Physical Data Channel

(DPDCH)

Dedicated Physical Control Channel

(DPCCH)

Downlink Physical ChannelsDownlink Physical Channels

Physical Downlink Shared Channel

(PDSCH)

Dedicated Physical

Channel(DPCH)

Acquisition Indicator Channel (AICH)

Collision Detection Channel Assignment

Indicator Channel (CD/CAICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Common Pilot Channel

(CPICH)

Common Control Physical Channel

(CCPCH)

Synchronisation Channel

(SCH)

• Primary

• Secondary

• Primary

• Secondary

• Primary

• Secondary

Frame StructureFrame Structure

Slot 0 Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 13Slot 14

Time

….

Frame= 10ms

Slot 0 Slot 1 ….

Slot = 666.67 µµµµs

Chiprate= 3.84 Mcps2560 chips

Spreading and Codes-FDD mode 1

Spreading and Codes-FDD mode 1

Spreading

Channelisation

+

Scrambling

�� OVSFOVSF

�� SF= code length per symbolSF= code length per symbol

�� SFSFmaxmax= = 256 (Uplink)256 (Uplink)

512 (Downlink)512 (Downlink)

�� SFSFminmin= 4= 4

�� Gold Codes Gold Codes

�� Per frame basisPer frame basis-- 38 400 chips38 400 chips

�� Downlink 2Downlink 21818-1

� Uplink 225 -1

�� S(2) codesS(2) codes

�� 256 chips256 chips

�� UplinkUplink-- if MUD usedif MUD used

FDD Synchronisation ChannelsFDD Synchronisation Channels

Slot 0 Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 13 Slot 14Time

….Frame= 10ms

….

….

P-SCH- Same code continuously

S-SCH- Code Pattern repeated over frames

Slot synchronisation

Frame synchronisation

Pattern Cell scrambling groupCell scrambling group

Frame Information Content-e.g. Downlink DCH

Frame Information Content-e.g. Downlink DCH


Time

….

Frame= 10ms

User

Data 1TPC TFCI

User

Data 2Pilot

10x 2k bits (k= 0…7)

2, 4, 8 or 16 bits

0, 2, 4, 8 or 16 bits

2, 4, 8, 16 or 32 bits

Multi-channel TransmissionMulti-channel Transmission

Physical Channel #1

Physical Channel #2

Physical Channel #n

User

Data 1

TPC TFCIUser

Data 2

Pilot

User

Data 1

User

Data 2

User

Data 1

User

Data 2

........

TransmissionPower

Transmission

Power

Transmission

Power

Frame Information Content-e.g. Uplink DCH

Frame Information Content-e.g. Uplink DCH


Time

….

Frame= 10ms

User Data

10x 2k bits (k= 0…6)

Pilot TFCI FBI TPC

1 or 2 bits

0, 1 or 2 bits

0, 2, 3 or 4 bits

10 bits

DPDCH

DPCCH

Contention-based Access SlotsContention-based Access Slots

Time

5120 chips

Radio frame = 10ms Radio frame = 10ms

Random Access Transmission




…..

Random Access BurstRandom Access Burst

Preamble Message part

10 or 20ms

Slot= 2560 chips

Data

10, 20, 40 or 80 bits

Pilot (8 bits) TFCI

Time

4096 bits

256x 16-chip signature≅ SF16

“Cell specific” scrambling code

Random Access ProcedureRandom Access Procedure

�� Signature setSignature set

�� Scrambling codeScrambling code

�� Preamble ack timerPreamble ack timer

�� Message lengthMessage length

�� Power offsetsPower offsets

�� Preamble/ controlPreamble/ control

�� control/ datacontrol/ data

Initial Preamble Power(open loop power control)

Uplink Access Slots

Signature

Generate Preamble

Transmit Preamble

Wait Acknowledgement(AICH)

Transmit Data/ Control Part

Retry (next access slot)

�� Power_rampPower_ramp

�� Max No. RTXMax No. RTX

Exit Procedure

No ACK

Any Downlink Physical Channel

(except SCH)

S/P

I

Q

Downlink SpreadingDownlink Spreading

x

x

OVSF

x

+ x

Complex value

Downlink scrambling code

Σ

x

x....x

Gi

Gj

Gk

Σx

Gp

x

Gs

To QPSK modulator

P-SCH

S-SCH

Physical Channel #1

j

I+jQ

+ x

Complex valueUplink Scrambling Code

x xDPDCH1

Spreading Code 1

Gain factor (data)

x xDPCCH

Fixed Spreading Code Gain factor (control)

x

j

I

Q

To QPSK modulator

Σ

x xDPDCH2

Spreading Code 2

Σx xDPDCH3

Spreading Code 3

x xDPDCH4

Spreading Code 4

x xDPDCH5

Spreading Code 5

x xDPDCH6

Spreading Code 6

Uplink Spreading (DCH)Uplink Spreading (DCH)

ModulationModulation

Separate

Real &

Imaginary

Real

Imaginary

Pulse Shaping

Pulse Shaping

x

Cos (ωt)

x

-Sin (ωt)

+

From spreading

(complex values)

To Transmission

FDD Power ControlFDD Power Control

�� Open LoopOpen Loop

�� Close LoopClose Loop

�� UplinkUplink


Node B

UE Transmits Preamble at computed Power

P-CCPCH

(BCH)

Node B


Up/ Down


Up/ Down

P-CCPCH

FDD Compressed modeFDD Compressed mode

�� PurposePurpose

�� Measurements at Measurements at ≠≠ frequencyfrequency

�� Reduction of Processing GainReduction of Processing Gain

�� CDMA: SF/2 orCDMA: SF/2 or

�� Coding: puncturingCoding: puncturing

�� Power increasedPower increased

Fame Fame Fame Fame

Transmission gap for inter-

frequency measurements

1 or 2 frames

Site Selection Diversity TransmitSite Selection Diversity Transmit

Cell C

Cell ACell B

FBI

(Primary cell)

DPCH

DPCCH

(Power Control)

DPCCH

(Power Ctl)

DPCH

FBI

(Primary cell)

DPCCH

(Power Control)

DPCCH

(Power Ctl)

Closed Loop Transmit DiversityClosed Loop Transmit Diversity

Spreading/Scrambling

DPCH

(Downlink)

x

x

w1

w2 Σ

Σ

CPICH1

CPICH2

Antenna 1

Antenna 2

FBI

Tx

Tx

Rx

RxWeight Generation

TDD Frame Structure ExamplesTDD Frame Structure Examples

Frame = 10msSlot = 2560 chips

Multi-switching-point/ symmetric DL/ UP allocation

Multi-switching-point/ asymmetric DL/ UP allocation

Single-switching-point/ symmetric DL/ UP allocation

Single-switching-point/ asymmetric DL/ UP allocation

TDD Burst StructuresTDD Burst Structures

Data Symbols TFCI Midamble TFCITPC Data Symbols GP

96 chipsBurst type 1 512 chips

Burst type 2 256 chips



(UL

optional)(UL/ DL

optional)

Data Symbols Midamble Data Symbols GP

192 chips512 chips976 chips 880 chips

RACH Burst

976/ 1104 chips

TDD specific spreadingTDD specific spreading


�� SF= 16 nominallySF= 16 nominally

�� SF= 1 possibleSF= 1 possible

�� UplinkUplink

�� SF= 1 to 16SF= 1 to 16

�� Two codes max per slot Two codes max per slot

per UEper UE

Symbol spreading/ channelisation

Data Symbols

Scrambling

Chips

Scrambling code

(16 chips long)

Channelisation code

(1-16 chips long)

Transmitted chips


Section 7Section 7

Universal Terrestrial Radio Access Universal Terrestrial Radio Access

NetworkNetwork

UTRAN InterfacesUTRAN Interfaces

Core

Network

Iu

RNC

IubIub

RNC

Iub Iub

Iu

IurSRNC

DRNC

General Protocol ModelGeneral Protocol Model

Application

Protocol

Radio

Network

Layer

Transport

Network

LayerSignallingBearer(s)

Data Stream(s)

DataBearer(s)

Transport Network

Control Plane

SignallingBearer(s)

ALCAP(s)

Transport Network

User Plane

Transport Network

User Plane


Physical Layer

Iu Interface ArchitectureIu Interface Architecture

Iu

Core Network

RNC

Circuit--switched Packet--switched

Iu-CSIu-PS

Broadcast

Iu-BC

Iu Interface CapabilitiesIu Interface Capabilities

�� Procedures to establish, maintain and release Radio Access Procedures to establish, maintain and release Radio Access Bearers;Bearers;

�� Procedures to perform intraProcedures to perform intra--system handover, intersystem handover, inter--system system handover and SRNS relocation;handover and SRNS relocation;

�� Procedures to support the Cell Broadcast service;Procedures to support the Cell Broadcast service;

�� General procedures between CN and UTRAN, not related to a General procedures between CN and UTRAN, not related to a specific UE;specific UE;

�� UE addressing capability for user specific signalling managementUE addressing capability for user specific signalling management;;

�� Transfer of NAS signalling messages between UE and CN;Transfer of NAS signalling messages between UE and CN;

�� Location based services;Location based services;

�� Simultaneous access to multiple CN domains for a single UE;Simultaneous access to multiple CN domains for a single UE;

�� Mechanisms for resource reservation for packet data streams.Mechanisms for resource reservation for packet data streams.

Iu CS Protocol ArchitectureIu CS Protocol Architecture

Radio

Network

Layer

Transport

Network

Layer

ATM

Physical Layer

UP Protocol Layer

AAL2

Transport Network

User Plane

User Plane

AAL2 SAR

RANAP

Transport Network

User Plane

Control Plane

AAL5

SCCP

Convergence layers

Transport Network

Control Plane

AAL5

AAL2 Signalling Protocol

Convergence layers

Iu PS Protocol ArchitectureIu PS Protocol Architecture

Radio

Network

Layer

Transport

Network

Layer

Transport Network

Control Plane

UP Protocol Layer

AAL5

Transport Network

User Plane

User Plane

IP

UDP

GTP-U

ATM

Physical Layer

RANAP

Transport Network

User Plane

Control Plane

ATM

Physical Layer

AAL5

SCCP

Convergence layers

Iu BC Protocol ArchitectureIu BC Protocol Architecture

Radio

NetworkLayer

Transport

Network

Layer

SABP Protocol Layer

AAL5

Transport Network

User Plane

SA Broadcast Plane

IP

TCP

ATM

Physical Layer

User Plane (UP) ProtocolsUser Plane (UP) Protocols

�� Transparent ModeTransparent Mode

�� Support Mode for predefined SDU sizeSupport Mode for predefined SDU size

Radio

Inte

rface

Pro

tocols

Iu UP layer inTransparent mode

Iu UP layer inTransparent mode

NAS

AS

Iu Interface

Radio

Inte

rface

Pro

tocols

Support modeFunctions

Support modeFunctions

NAS

AS

Iu Interface

Iu UP

Protocol frames

Iur Interface CapabilitiesIur Interface Capabilities

SRNC DRNC Iub

Iur

Radio application related signalling

Transport channel

data stream

Iur Protocol ArchitectureIur Protocol Architecture

Radio

Network

Layer

Transport

Network

Layer

Iur Data Stream

AAL2

Transport Network

User Plane

User Plane

AAL2 SAR

RNSAP

Transport Network

User Plane

Control Plane

AAL5

SCCP

Convergence Layers

Transport Network

Control Plane

AAL5

AAL2 connection Signalling

Convergence Layers

ATM

Physical Layer

SRNC RelocationSRNC Relocation

Core

Network

Iu

Iur

SRNC DRNC

1-R

eloc

atio

n re

quire

d

4-R

eloc

atio

n co

mm

and

2- Relocation request

3- Relocation request Ack

5- Relocation commit

6- Relocation detect

7- ID exchange with UE

8- Relocation com

plete9-Iu

Rel

ease

com

man

d

10-Iu

Rel

ease

com

plet

e

Iub Interface CapabilitiesIub Interface Capabilities

RNC

Iub

Transport Channel Data Stream

Radio application related signalling

& Node management

Iub Protocol ArchitectureIub Protocol Architecture

Radio

Network

Layer

Transport

Network

Layer

ATM

Physical Layer

Iur Data Stream

AAL2

Transport Network

User Plane

User Plane

AAL2 SAR

NBAP

Transport Network

User Plane

Control Plane

AAL5

SSCOP

SSCF-NNI

Transport NetworkControl Plane

AAL5

SSCF-NNI

AAL2 Signalling Transport

converter

AAL2 connection Signalling

SSCOP

RAB Establishment within UTRAN

Example (no DRNC)

RAB Establishment within UTRAN

Example (no DRNC)

CNCNRNCRNCNode BNode BUEUE

RANAPRANAPRAB Assignment

Request (establish)NBAPNBAP

Radio Link Setup

Request

NBAPNBAPRadio Link Setup

Response

ALCAP Iub Data Transport Bearer Setup

ALCAP Iu Data Transport Bearer Setup(not required towards PS)

RRCRRCRadio Bearer Setup


Response

Not required

For RACH/ FACH

RAB Release within UTRAN

Example (no DRNC)

RAB Release within UTRAN

Example (no DRNC)

CNCNRNCRNCNode BNode BUEUE


Request (release)

NBAPNBAP

Radio Link

ReconfigurationRequest

NBAPNBAP

RL Reconfiguration

Response

ALCAP Iub Data Transport Bearer Setup

ALCAP Iu Data Transport Bearer Setup

(not required towards PS)

RRCRRCRadio Bearer Release


Response

Not required

For RACH/ FACH

Synchronisation IssuesSynchronisation Issues

Core Network

RNS

NodeB

NodeB

NodeB

….

Vocoder

RNC

NodeB

NodeB

….

UTRAN

RNC

UE1 UE2

Time

AlignmentHandling

Transport

ChannelSynchronisation

Radio

InterfaceSynchronisation [TDD] Radio

InterfaceSynchronisation

Cdma and Umts Basics

Documents

operation section

characteristics section

cdma systemsunderstand

different code types

ds fast fhpncode

synchronisation requirements

importance of power

w x log2