3G CDMA - WCDMA and cdma2000
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Transcript 3G CDMA - WCDMA and cdma2000
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
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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* 2k 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
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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 )
clong,1
May 28-June1, 2001
clong,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 data 2
DPCCH
Pilot
0.667 ms
slot i
slot 14
radio frame = 10 ms
N data2 N data2 10* 2k 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 Gn
Primary
Sync Code
e j t
CP
GP
Secondary
Sync Code
clong,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
clong,I
+
clong,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
01
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
YI
+
-
pulse
shape
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
01
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
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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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