3G CDMA - WCDMA and
cdma2000
Rodger E. Ziemer
IEEE Communications Society
Distinguished Lecturer Program
Rules for Efficient Multiple Access
 Three
laws
 Know
the channel
 Minimize interference to others
 Mitigate interference received from others
 Requirements
of wireless multiple access
 Channel
measurement
 Channel control and modification
 Multiple user channel isolation
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
2
Why CDMA?
Higher capacity
 Improved performance in multipath by diversity
 Lower mobile transmit power = longer battery life

Power control
 Variable transmission rate with voice activity detection

Allows soft handoff
 Sectorization gain
 High peak data rates can be accommodated
 Combats other-user interference = lower reuse factors

May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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What is Third Generation? [1]

Flexible support of multiple services
Voice
 Messaging – email, fax, etc.
 Medium-rate multimedia – Internet access, educational
 High-rate multimedia – file transfer, video
 High-rate interactive multimedia – video telecon-ferencing,
telemedicine, etc.

Mobility: quasi-stationary to high-speed platforms
 Global roaming: ubiquitous, seamless coverage
 Evolution from second generation systems

May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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W-CDMA Versus cdma2000 [2]
Parameter
W-CDMA
cdma2000
Carrier spacing
5 MHz
3.75 MHz
Chip rate
4.096 MHz
3.6864 MHz
Data modulation
BPSK
FW – QPSK; RV - BPSK
Spreading
Complex (OQPSK)
Complex (OQPSK)
Power control frequency
1500 Hz
800 Hz
Variable data rate implement.
Variable SF; multicode
Repet., puncturing, multicode
Frame duration
10 ms
20 ms (also 5, 30, 40)
Coding
Turbo and convolutional
Turbo and convolutional
Base stations synchronized?
Asynchronous
Synchronous
Base station acquisition/detect
3 step; slot, frame, code
Time shifted PN correlation
Forward link pilot
TDM dedicated pilot
CDM common pilot
Antenna beam forming
TDM dedicated pilot
Auxiliary pilot
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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WCDMA Uplink Frame Structure [1]
N data  10 * 2 k bits (k  0,,6)
I: data channel
DPDCH
Tslot  2560 chips
Q: sync & control
Pilot:
N pilot bits
TFCI
FBI
TPC
DPCCH
0.667 ms
slot 0 slot 1
slot i
slot 14
radio frame = 10 ms
TFCI = transmit format combination indicator
FBI = feedback information
TPC = transmit power control
May 28-June1, 2001
DPDCH = dedicated physical data channel
DPCCH = dedicated physical control channel
R. Z. Ziemer, Colorado Springs, CO
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WCDMA Uplink Modulator Structure [1]
DPDCH1
+
d
cd ,1

DPDCH3
c d ,3

I
-
pulse shape
filter (SRC)
cos(  c t )
d
+

+
DPDCH2
cd , 2
d

DPCCH
cc
Q
+
c
+

pulse shape
filter (SRC)
sin(  c t )
c long,1
May 28-June1, 2001
c long,2
R. Z. Ziemer, Colorado Springs, CO
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Orthogonal Variable Spreading Factor Codes
Cd, i selected from this tree
00000000
0000
00001111
00
00110011
0011
00111100
0
01010101
0101
01011010
01
01100110
0110
01101001
May 28-June1, 2001
Notes:
1) For fixed chip rate, desired information
rate determines length of spreading
sequence and therefore processing gain.
2) When a specific code is used, no other
code on the path from that code to the root
and or on the subtree beneath that
code may be used.
3) All the codes at any depth into the tree
are the set of Walsh Sequences.
4) Code phase is synchronous with
information symbols.
5) FDD UL processing gain between 256 and 4
FDD DL processing gain between 512 and 4
TDD UL/DL processing gain between 16 and 1
6) Multicode used only for SF = 4
R. Z. Ziemer, Colorado Springs, CO
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WCDMA Downlink Frame Structure [1]
DPDCH
DPDCH
DPCCH
Data1 N data1 TPC
TFCI
Data2
Tslot  2560 chips
slot 0 slot 1
N data2
DPCCH
Pilot
0.667 ms
slot i
slot 14
radio frame = 10 ms
N data2  N data2  10 * 2 k bits (k  0,,7)
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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WCDMA Downlink Modulator Structure [1]
dedicated
traffic channels
primary &
secondary
common pilot
channels
s/p
primary &
secondary
common
control
channels
cd ,1
Clong
s/p
G1
cd , n
pulse shape
filter (SRC)
other channels
Clong
Primary
Sync Code
Gn
e j t
CP
GP
Secondary
Sync Code
c long,2
CS
GS
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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Transmit Diversity Strategy for Downlink
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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cdma2000 Uplink Frame Structure
Radio Configuration 3
channel
bits
Bits/
Frame
16
40
80
172
350
744
1512
3048
6120
modulation
symbol
CRC
encoder
tail bits
CRC
bits
6
6
8
12
16
16
16
16
16
tail
bits
8
8
8
8
8
8
8
8
8
Convolutional
or Turbo Coder
Data Rate
kbps
1.5
2.7
4.8
9.6
19.2
38.4
76.8
153.6
307.2
Code
Rate
1/4
1/4
1/4
1/4
1/4
1/4
1/4
1/4
1/2
symbol
repetition
symbol
puncture
block
interleaver
Repeats
16
8
4
2
1
1
1
1
1
Delete
1 of 5
1 of 9
none
none
none
none
none
none
none
Symbols
1536
1536
1536
1536
1536
3072
6144
12288
12288
C
C.S.0002-A-1 Fig 2.1.3.1.1.1-8
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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cdma2000 Uplink Modulator
Secondary
Traffic 2 C
wS 2
Pilot
+ 
_
d
pulse
shape
A
cos(  c t )
Control
B
wC
+
c

+
Primary
C
Traffic
wD1
d
+
Secondary
Traffic 1 C
wS1
May 28-June1, 2001
d
c long,I
+

c long,Q
R. Z. Ziemer, Colorado Springs, CO
pulse
shape
sin(  c t )
13
cdma2000 Downlink Frame Structure
Radio Configuration 9
channel
bits
Bits/
Frame
21
55
125
267
552
1128
2280
4584
9192
20712
modulation
symbol
CRC
CRC
bits
6
8
10
12
16
16
16
16
16
16
encoder
tail bits
tail
bits
8
8
8
8
8
8
8
8
8
8
Convolutional
or Turbo Coder
Data Rate
kbps
1.8
3.6
7.2
14.4
28.8
57.6
115.2
230.4
460.8
1036.8
Code
Rate
1/2
1/2
1/2
1/2
1/2
1/2
1/2
1/2
1/2
1/2
symbol
repetition
Repeats
8
4
2
1
1
1
1
1
1
1
symbol
puncture
Delete
none
none
none
none
none
none
none
none
none
2 of 18
block
interleaver
W
Symbols
576
576
576
576
1152
2304
4608
9216
18432
36864
Other similar tables in specification.
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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+
W
modulation
symbol
rate
01
1  -1
power
control
bits
channel
gain
fwd pwr
ctrl gain
long
code
YI
YQ
puncture
timing
800 Hz
I/Q scrambling
bit extract
long
code
mask
power control
symbol puncture
cdma2000 1X DL Modulation
Processing
decimate
pwr ctrl
bit pos
C.S.0002-A-1 Fig 3.1.3.1.1.1-18
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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cdma2000 1X Downlink Modulation
other
channels
XI
+

-
pulse
shape

YI
cos(  c t )
Walsh code

QOF code
YQ

+
other
channels
+

XQ
I channel
pilot PN
May 28-June1, 2001
Q channel
pilot PN
R. Z. Ziemer, Colorado Springs, CO
pulse
shape
sin(  c t )
16
+
W
modulation
symbol
rate
01
1  -1
power
control
bits
channel
gain
fwd pwr
ctrl gain
long
code
May 28-June1, 2001
YI1
YI2
decimate
YQ2
YQ3
pwr ctrl
bit pos
R. Z. Ziemer, Colorado Springs, CO
YQ1
YI3
puncture
timing
800 Hz
I/Q scrambling
bit extract
long
code
mask
power control
symbol puncture
cdma2000 3X DL Modulation
Processing
17
cdma2000 3X Downlink Modulation
YI1
same as below
output
carrier 1
YQ1
YI2
output
carrier 2
YQ2
YI3
same as above
output
carrier 3
YQ3
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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cdma2000 vs WCDMA
 Chip
rate
 Coherent Pilot Channels
 Transmit Diversity
 Underlying Network
 Single Carrier versus Multicarrier Spreading
 Cell Site Synchronization
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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References
[1] R. L. Peterson, “Third Generation Personal Communications: Physical Layer
Status,” Presentation at Clemson University, Feb. 1, 2001
[2] Manjit Singh and Manoneet Singh, “3G Wireless with Respect to IMT-2000 and
Beyond,” Telecom 99
[3] Harri Holma and Antti Toskala, WCDMA for UMTS: Radio Access for Third
Generation Mobile Communications, New York: Wiley, 2000
[4] “CDMA Evolution from IS-95, IS-2000, to 1XTREME,” Technology Transfer
Training Class, Motorola, Inc., July 2000
[5] R. Ziemer and R. Peterson, Introduction to Digital Communications, Upper
Saddle River, NJ: Prentice Hall, Chapter 10, 2001
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
20
WCDMA: More Information?

http://www.3gpp.org
21.101  guide to all other documents
 25.XXX series  radio access network (RAN)

25.211
 25.212
 25.213
 25.214
 25.321
 25.322


 frame structure etc.
 channel coding etc.
 spreading and modulation
 physical layer procedures (tx diversity, etc.)
 medium access control (MAC)
 radio link control (RLC)
26.XXX series  voice coding
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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GSM/GPRS/EDGE: More Information?
 http://www.3gpp.org
3GPP
ETSI
description
45.001
05.01
general description
45.002
05.02
multiple access, logical channels, etc
45.003
05.03
channel coding
45.004
05.04
modulation
45.005
05.05
radio
transmission and channel
models
45.008
05.08
radio link control
45.009
05.09
link adaptation
44.060
04.60
RLC/MAC
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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cdma2000: More Information?
 http://www.3gpp2.org
Specification Group C  cdma2000
 C.S0002-A-1  Physical Layer Standard
 C.S0003-A-1  Medium Access Control (MAC)
 C.S0004-A-1  Signaling Link Access Control
 C.S00024
 1XEV-DO (high speed packet)
 C.S0005
 Upper Layer Signaling (L3)
 Technical
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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3G Information Sources




Third Generation Partnership Projects
 http://www.3gpp.org
 http://www.3gpp2.org
CDMA Development Group (CDG)
 http://www.cdg.org
International Mobile Telecommunications for the year 2000
 http://www.tiaonline.org/standards/sfg/imt2k/
Japan ARIB IMT-2000 proposal
 http://www.arib.or.jp/IMT-2000/ARIB/Document/
May 28-June1, 2001
R. Z. Ziemer, Colorado Springs, CO
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