1. WCDMA RAN Overview
1
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WCDMA RAN Overview
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Objectives
 Upon completion of this course, you will be able to:
 Describe the development of 3G
 Outline the advantage of CDMA principle
 Characterize code sequence
 Outline the fundamentals of RAN
 Describe feature of wireless propagation

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Contents
1. 3G Overview
2. CDMA Principle
3. WCDMA Network Architecture and protocol structure
4. WCDMA Wireless Fundamental
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Different Service, Different Technology
AMPS
TACS
NMT
Others
1G 1980s
Analog
GSM
CDMA
IS-95
TDMA
IS-136
PDC
2G 1990s
Digital
Technologies
drive
3G
IMT-2000
UMTS
WCDMA
cdma
2000Demands
drive
TD-SCDMA
3G provides compositive services for both operators and subscribers
WIMAX

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3G Evolution
 Proposal of 3G
 IMT-2000: the general name of third generation mobile
communication system
 The third generation mobile communication was first proposed
in 1985，and was renamed as IMT-2000 in the year of 1996
 Commercialization: around the year of 2000
 Work band : around 2000MHz
 The highest service rate :up to 2000Kbps
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3G Spectrum Allocation

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Bands WCDMA Used
 Main bands
 1920 ~ 1980MHz / 2110 ~ 2170MHz
 Supplementary bands: different country maybe different
 1850 ~ 1910 MHz / 1930 MHz ~ 1990 MHz (USA)
 1710 ~ 1785MHz / 1805 ~ 1880MHz (Japan)
 890 ~ 915MHz / 935 ~ 960MHz (Australia)
 . . .
 Frequency channel number＝central frequency×5, for main
band:
 UL frequency channel number ：9612～9888
 DL frequency channel number : 10562～10838
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3G Application Service
Time Delay
Error
Ratio
background
conversational
streaming
interactive

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The Core technology of 3G: CDMA
CDMA
WCDMA
CN: based on MAP and GPRS
RTT: WCDMA
TD-SCDMA
CN: based on MAP and GPRS
RTT: TD-SCDMA
cdma2000
CN: based on ANSI 41 and MIP
RTT: cdma2000
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Contents
1. 3G Overview
2. CDMA Principle
3. WCDMA Network Architecture and protocol structure
4. WCDMA Wireless Fundamental

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Multiple Access and Duplex Technology
 Multiple Access Technology which used to differentiate user
 Frequency division multiple access (FDMA)
 Time division multiple access (TDMA)
 Code division multiple access (CDMA)
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Multiple Access Technology
Power
FDMA
Power
TDMA
Power
CDMA

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Multiple Access and Duplex
Technology
 Duplex Technology which used to discriminate UL and DL
 Frequency division duplex (FDD)
 Time division duplex (TDD)
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Duplex Technology
Time
Frequency
Power
TDD
USER 2
USER 1
DL
UL
DL
DL
UL
FDD
Time
Frequency
Power
UL DL
USER 2
USER 1

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Contents
1. 3G Overview
2. CDMA Principle
3. WCDMA Network Architecture and protocol structure
4. WCDMA Wireless Fundamental
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WCDMA Network Architecture
RNS
RNC
RNS
RNC
Core Network
Node B Node B Node B Node B
Iu-CS Iu-PS
Iur
Iub IubIub Iub
CN
UTRAN
UE
Uu
CS PS
Iu-CSIu-PS
CSPS

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WCDMA Network Version Evolution
3GPP Rel99
3GPP Rel4
3GPP Rel5
2000 2001 2002
GSM/GPRS CN
WCDMA RTT
IMS
HSDPA 3GPP Rel6
MBMS
HSUPA
2005
CS domain change to
NGN
WCDMA RTT
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WCDMA Network Version Evolution
 Features of R6
 MBMS is introduced
 HSUPA is introduced to achieve the service rate up to 5.76Mbps
 Features of R7
 HSPA+ is introduced, which adopts higher order modulation and
MIMO
 Max DL rate: 28Mbps, Max UL rate:11Mbps
 Features of R8
 New HSPA+ technology is introduced, which adopts 64QAM+MIMO
or 64QAM+DC in downlink (Defined by 3GPP 25.XXX)
 Max DL rate: 42Mbps, Max UL rate: 11Mbps

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WCDMA Network Version
Evolution(Cont.)
 Features of R9
 Some new HSPA+ technology is introduced, include DC-HSDPA
+MIMO+64QAM and DC-HSUPA
 Max DL rate: 84Mbps, Max UL rate: 23Mbps
Page
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Uu Interface protocol structure
L3
control
control
control
control
C-plane signaling U-plane information
PHY
L2/MAC
L1
RLC
DCNtGC
L2/RLC
MAC
RLC
RLC
RLC
Duplication avoidance
UuS boundary
L2/BMC
control
PDCPPDCP L2/PDCP
DCNtGC
RRC
RLC
RLC
RLC
RLC
BMC

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General Protocol Mode for UTRAN
Terrestrial Interface
 The structure is based on the principle that the layers and planes
are logically independent of each other.
Application
Protocol
Data
Stream(s)
ALCAP(s)
Transport
Network
Layer
Physical Layer
Signaling
Bearer(s)
Control Plane User Plane
Transport Network
User Plane
Transport Network
Control Plane
Radio
Network
Layer
Signaling
Bearer(s)
Data
Bearer(s)
Transport Network
User Plane
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Iu-CS Interface (based on IP)
Control Plane User planeRadio
Network
Layer
Transport Network
User Plane
Transport
Network
Layer
RANAP
IP
Physical Layer
IP
SCTP
Iu UP
Transport Network
User Plane
DATA LINK DATA LINK
M3UA
SCCP
RTP/RTCP
UDP

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Iu-PS Interface (based on IP)
Control Plane User planeRadio
Network
Layer
Transport Network
User Plane
Transport
Network
Layer
RANAP
IP
Physical Layer
IP
SCTP
Iu UP
Transport Network
User Plane
DATA LINK DATA LINK
M3UA
SCCP
GTP-U
UDP
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Iub Interface (based on IP)
Control Plane User planeRadio
Network
Layer
Transport Network
User Plane
Transport
Network
Layer
Transport Network
User Plane
NBAP
IP
DATA LINK
Physical Layer
IP
Iub FP
NCP CCP
DATA LINK
SCTP UDP

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Iur Interface (based on IP)
Control Plane User planeRadio
Network
Layer
Transport Network
User Plane
Transport
Network
Layer
RNSAP
IP
Physical Layer
IP
SCTP
Iur Data
Stream
Transport Network
User Plane
DATA LINK DATA LINK
M3UA
SCCP
UDP
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Contents
1. 3G Overview
2. CDMA Principle
3. WCDMA Network Architecture and protocol structure
4. WCDMA Wireless Fundamental

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Processing Procedure of WCDMA System
Source
Coding
Channel Coding
& Interleaving
Spreading Modulation
Source
Decoding
Channel Decoding
& Deinterleaving
Despreading Demodulation
Transmission
Reception
chip
modulated
signal
bit symbol
Service
Signal
Radio
Channel
Service
Signal
Receiver
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WCDMA Source Coding
 AMR (Adaptive Multi-Rate)
Speech
 A integrated speech codec with 8
source rates
 The AMR bit rates can be controlled
by the RAN depending on the system
load and quality of the speech
connections
 Video Phone Service
 H.324 is used for VP Service in CS
domain
 Includes: video codec, speech codec,
data protocols, multiplexing and etc.
CODEC Bit Rate (kbps)
AMR_12.20 12.2 (GSM EFR)
AMR_10.20 10.2
AMR_7.95 7.95
AMR_7.40 7.4 (TDMA EFR)
AMR_6.70 6.7 (PDC EFR)
AMR_5.90 5.9
AMR_5.15 5.15
AMR_4.75 4.75

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Processing Procedure of WCDMA System
Transmitter
Source
Coding
Channel Coding
& Interleaving
Spreading Modulation
Source
Decoding
Channel Decoding
& Deinterleaving
Despreading Demodulation
Transmission
Reception
chip
modulated
signal
bit symbol
Service
Signal
Radio
Channel
Service
Signal
Receiver
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WCDMA Block Coding - CRC
 Block coding is used to detect if there are any uncorrected
errors left after error correction.
 The cyclic redundancy check (CRC) is a common method of
block coding.
 Adding the CRC bits is done before the channel encoding
and they are checked after the channel decoding.

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WCDMA Channel Coding
 Effect
 Enhance the correlation among symbols so as to recover the signal when
interference occurs
 Provides better error correction at receiver, but brings increment of the delay
 Types
 Convolutional Coding (1/2, 1/3)
 Turbo Coding (1/3)
Code Block
of N Bits
1/2 Convolutional
Coding
1/3 Convolutional
Coding
1/3 Turbo Coding
Coded 2N+16 bits
Coded 3N+24 bits
Coded 3N+12 bits
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WCDMA Interleaving
 Effect
 Interleaving is used to reduce the probability of consecutive bits error
 Longer interleaving periods have better data protection with more delay
















1110
1.........
............
...000
0100
0 0 1 0 0 0 0 . . . 1 0 1 1 1
















1110
1.........
............
...000
0100
0 0 … 0 1 0 … 1 0 0 … 1 0 … 1 1
Inter-column
permutation
Output bits
Input bits
Interleaving periods:
20, 40, or 80 ms

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Processing Procedure of WCDMA System
Source
Coding
Channel Coding
& Interleaving
Spreading Modulation
Source
Decoding
Channel Decoding
& Deinterleaving
Despreading Demodulation
Transmission
Reception
chip
modulated
signal
bit symbol
Service
Signal
Radio
Channel
Service
Signal
Receiver
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Correlation
 Correlation measures similarity between any two arbitrary signals.
 Identical and Orthogonal signals:
Correlation = 0
Orthogonal signals
-1 1 -1 1

-1 1 -1 1
1 1 1 1
+1
-1
+1
-1
+1
-1
+1
-1
Correlation = 1
Identical signals
-1 1 -1 1

1 1 1 1
-1 1 -1 1
C1
C2
+1
+1
C1
C2

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Orthogonal Code Usage - Coding
UE1: ＋1 －1
UE2: －1 ＋1
C1 : －1 ＋1 －1 ＋1 －1 ＋1 －1 ＋1
C2 : ＋1 ＋1 ＋1 ＋1 ＋1 ＋1 ＋1 ＋1
UE1×c1： －1 ＋1 －1 ＋1 ＋1 －1 ＋1 －1
UE2×c2： －1 －1 －1 －1 ＋1 ＋1 ＋1 ＋1
UE1×c1＋ UE2×c2： －2 0 －2 0 ＋2 0 ＋2 0
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Orthogonal Code Usage - Decoding
UE1×C1＋ UE2×C2: －2 0 －2 0 ＋2 0 ＋2 0
UE1 Dispreading by c1: －1 ＋1 －1 ＋1 －1 ＋1 －1 ＋1
Dispreading result: ＋2 0 ＋2 0 －2 0 －2 0
Integral judgment: ＋4 (means＋1) －4 (means－1)
UE2 Dispreading by c2: ＋1 ＋1 ＋1 ＋1 ＋1 ＋1 ＋1 ＋1
Dispreading result: －2 0 －2 0 ＋2 0 ＋2 0
Integral judgment: －4 (means－1) ＋4 (means＋1)

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Spectrum Analysis of Spreading & Dispreading
Spreading code
Spreading code
Signal
Combination
Narrowband signal
f
P(f)
Broadband signal
P(f)
f
Noise & Other Signal
P(f)
f
Noise+Broadband signal
P(f)
f
Recovered signal
P(f)
f
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Spectrum Analysis of Spreading & Dispreading
Max allowed interference
Eb/No
Requiremen
t
Power
Max interference caused
by UE and others
Processing Gain
Ebit
Interference from
other UE
Echip
Eb / No = Ec / No ×PG

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Process Gain
 Process Gain
 Process gain differs for each service.
 If the service bit rate is greater, the process gain is smaller, UE
needs more power for this service, then the coverage of this
service will be smaller, vice versa.
)
ratebit
ratechip
log(10GainocessPr 
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Spreading Technology
 Spreading consists of 2 steps:
 Channelization operation, which transforms data symbols into chips
 Scrambling operation is applied to the spreading signal
scramblingchannelization
Data
symbol
Chips after
spreading

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WCDMA Channelization Code
 OVSF Code (Orthogonal Variable Spreading Factor) is used as
channelization code
SF = 8SF = 1 SF = 2 SF = 4
Cch,1,0 = (1)
Cch,2,0 = (1,1)
Cch,2,1 = (1, -1)
Cch,4,0 = (1,1,1,1)
Cch,4,1 = (1,1,-1,-1)
Cch,4,2 = (1,-1,1,-1)
Cch,4,3 = (1,-1,-1,1)
Cch,8,0 = (1,1,1,1,1,1,1,1)
Cch,8,1 = (1,1,1,1,-1,-1,-1,-1)
Cch,8,2 = (1,1,-1,-1,1,1,-1,-1)
Cch,8,3 = (1,1,-1,-1,-1,-1,1,1)
Cch,8,4 = (1,-1,1,-1,1,-1,1,-1)
Cch,8,5 = (1,-1,1,-1,-1,1,-1,1)
Cch,8,6 = (1,-1,-1,1,1,-1,-1,1)
Cch,8,7 = (1,-1,-1,1,-1,1,1,-1)
……
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WCDMA Channelization Code
 SF = chip rate / symbol rate
 High data rates → low SF code
 Low data rates → high SF code
Radio bearer SF Radio bearer SF
Speech 12.2 UL 64 Speech 12.2 DL 128
Data 64 kbps UL 16 Data 64 kbps DL 32
Data 128 kbps UL 8 Data 128 kbps DL 16
Data 144 kbps UL 8 Data 144 kbps DL 16
Data 384 kbps UL 4 Data 384 kbps DL 8

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Purpose of Channelization Code
 Channelization code is used to distinguish different physical
channels of one transmitter
 For downlink, channelization code ( OVSF code ) is used to
separate different physical channels of one cell
 For uplink, channelization code ( OVSF code ) is used to
separate different physical channels of one UE
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Scrambling Code
 Scrambling code: GOLD sequence.
 There are 224 long uplink scrambling codes which are used for
scrambling of the uplink signals. Uplink scrambling codes are
assigned by RNC.
 For downlink, 512 primary scrambling codes are used.

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Purpose of Scrambling Code
 Scrambling code is used to distinguish different transmitters
 For downlink, scrambling code is used to separate different
cells in one carrier
 For uplink, scrambling code is used to separate different UEs
in one carrier
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Primary Scrambling Code Group
Primary
scrambling
codes for
downlink
physical
channels
Group 0
…
Primary
scrambling code 0
……
Primary
scrambling code
8*63
……
Primary
scrambling code
8*63 +7
512 primary
scrambling
codes
…………
Group 1
Group 63
Primary
scrambling code 1
Primary
scrambling code 7
64 primary
scrambling code
groups
Each group consists of 8
primary scrambling codes

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Code Multiplexing
 Downlink Transmission on a Cell Level
Scrambling code
Channelization code 1
Channelization code 2
Channelization code 3
User 1 signal
User 2 signal
User 3 signal
NodeB
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Code Multiplexing
 Uplink Transmission on a Cell Level
NodeB
Scrambling code 3
User 3 signal
Channelization code
Scrambling code 2
User 2 signal
Channelization code
Scrambling code 1
User 1 signal
Channelization code

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Processing Procedure of WCDMA System
Source
Coding
Channel Coding
& Interleaving
Spreading Modulation
Source
Decoding
Channel Decoding
& Deinterleaving
Despreading Demodulation
Transmission
Reception
chip
modulated
signal
bit symbol
Service
Signal
Radio
Channel
Service
Signal
Receiver
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Modulation Overview
1 00 1
time
Basic steady radio
wave:
carrier = A.cos(2pFt+f)
Amplitude Shift
Keying:
A.cos(2pFt+f)
Frequency Shift
Keying:
A.cos(2pFt+f)
Phase Shift Keying:
A.cos(2pFt+f)
Data to be transmitted:
Digital Input

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Modulation Overview
 Digital Modulation - BPSK
1
t
1 10
1
t
-1
NRZ coding
fo
BPSK
Modulated
BPSK
signal
Carrier
Information
signal
f=0 f=p f=0
1 102 3 4 9875 6
1 102 3 4 9875 6
Digital Input
High Frequency
Carrier
BPSK Waveform
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Modulation Overview
 Digital Modulation - QPSK
-1 -1
1 102 3 4 9875 6
1 102 3 4 9875 6
NRZ Input
I di-Bit Stream
Q di-Bit Stream
I
Component
Q
Component
QPSK Waveform
1
1
-1
1
-1
1
1
-1
-1
-1
1 1 -1 1 -1 1 1 -1

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Modulation Overview
NRZ
coding
90o
NRZ
coding
QPSK
Q(t)
I(t)
fo
±A
±A ±Acos(ot)
±Acos(ot + p/2)
f
1 1 p/4
1 -1 7p/4
-1 1 3p/4
-1 -1 5p/4
)cos(2: f tAQPSK o
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Demodulation
 QPSK Constellation Diagram
1 102 3 4 9875 6
QPSK Waveform
1,1
-1,-1
-1,1
1,-1
1 -11 -1 1 -1-11-1 1
-1,1
NRZ Output

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I
Page
WCDMA Modulation
 Different modulation methods corresponding to different
transmitting abilities in air interface
HSDPA: QPSK or 16QAMR99/R4: QPSK
00
01 10
11
I
Q
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Processing Procedure of WCDMA System
Source
Coding
Channel
Coding
Spreading Modulation
Source
Decoding
Channel
Decoding
Despreading Demodulation
Transmission
Reception
chip
modulated
signalbit symbol
Service
Signal
Radio
Channel
Service
Signal
Transmitter
Receiver

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Wireless Propagation
Received
Signal
Transmitted
Signal
Transmission Loss:
Path Loss + Multi-path Fading
Time
Amplitude
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Propagation of Radio Signal
Signal at Transmitter
Signal at Receiver
-40
-35
-30
-25
-20
-15
-10
-5
dB
0
0
dBm
-20
-15
-10
-5
5
10
15
20
Fading

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Fading Categories
 Fading Categories
 Slow Fading
 Fast Fading
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Diversity Technique
 Diversity technique is used to obtain uncorrelated signals for
combining
 Reduce the effects of fading
 Fast fading caused by multi-path
 Slow fading caused by shadowing
 Improve the reliability of communication
 Increase the coverage and capacity

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Diversity
 Time diversity
 Channel coding, Block interleaving
 Frequency diversity
 The user signal is distributed on the whole bandwidth
frequency spectrum
 Space diversity
 Polarization diversity
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Principle of RAKE Receiver
Receive set
Correlator 1
Correlator 2
Correlator 3
Searcher correlator Calculate the
time delay and
signal strength
Combiner
The
combined
signal
tt
s(t) s(t)
RAKE receiver help to overcome on the multi-path fading and enhance the receive
performance of the system

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Soft Handover
Page
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Summary
 In this course, we have discussed basic concepts of WCDMA:
 Spreading / Despreading principle
 UTRAN Voice Coding
 UTRAN Channel Coding
 UTRAN Spreading Code
 UTRAN Scrambling Code
 UTRAN Modulation
 UTRAN Transmission/Receiving

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Thank you
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