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8/3/2019 ZTE CDMA Principles
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General Introduction to CDMA Mobile Communications
CDMA Business Department
Shenzhen ZTE Corporation, China
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Contents
Overview of Mobile Communications
Technical Features of CDMA
Dynamics of 3 G ( the 3rd Generation
Communications System)
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Basic Concepts of Cellular Mobile Communication
Cell/sector
Frequency Reuse
Handoff
Cell-splitting
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Mobility
flexible and convenientglobal personal
communication
Poor environment and conditions Co-channel interference, multi-path(space
and time)shadow effect and delay, power
change and other noise,
MultipleMS and channels Interferencenear and far effect
Limit of frequency resources
Reliability is a must
registration, handoff, switching, control
Characteristics of Mobile Communication
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1946 First mobile phone system , 120 KHZ( AT&T): FM
60s IMTS 25-30KHZ Bell System): FM 1 G Analog Cellular/FDMA
AMPS (US, 800 MHZ/30KHZ/10 kbps)
TACS (British, 900 MHZ/25 KHZ/8 kbps)
2 G digital cellular/TDMA GSM, DAMPS, JDC
IS-95 CDMA
3G IMT-2000 (International Mobile telecommunications)
UTRA/W-CDMA (Japan, Europe)
CDMA 2000 MC (US)
UTRA TDD (Europe) and TD-SCDMA(China)
UWC-136 (TDMA)
DECT (TDMA)
Evolution of Mobile Communications System
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Concepts: FDMA, TDMA & CDMA
FDMA TDMACDMA
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Channel: An individually-assigned, dedicatedpathway through a transmission medium for oneuser information
Any of the dimensions of the transmitted signalcan be segmented into private assigned channelsfor users. Here how the three most populartechnologies establish channels:
FDMA:Frequency Division Multiple Accesseach user on a different frequency
a channel is a frequency
TDMA: Time Division Multiple Access
each user on a different window periodin time slot
a channel is a specific time slot on aspecific frequency
CDMA: Code Division Multiple Access
each user uses the same frequency all thetime, but mixed with differentdistinguishing code patterns
a channel is a unique code pattern
Power
Power
Power
FDMA
TDMA
CDMA
Channel Structure For FDMA/TDMA/CDMA
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Frequency Reuse and Large Capacity
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Comparison between CDMA & GSM System (1)
Cell Coverage
CDMA: varies with traffic load
No load: 3 GSM coverage
20 channels/sector: 2 GSM coverage
GSM: coverage not affected by traffic load
Number of BTS
CDMA=20% GSM
1000 km2 coverage: CDMA 45 BTS, GSM 200 BTS
Capacity:
CDMA=5 GSM=10 AMPS
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Voice quality: vocoder
CDMA 8K> GSM 13K, CDMA 13K approaches 64K PCM
Handoff
CDMA : soft handoff, GSM: hard handoff, more
dropped calls Network Planning and Expansion
CDMA : simple ( N=1), GSM: more complicated (N=4/7)
Comparison between CDMA & GSM System (2)
13
2
4
3
2
4
2
4
4
1
2
3
14
2
3
1
4
GSMN4 CDMAN1
11
1
11 1
1
11
1
1
1
1
1
1
1
11
1
11
1
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Contents
Overview of Mobile Communications
Technical Features of CDMA
Dynamics of 3 G ( the 3rd Generation
Communications System)
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Technical Features of CDMA
Spread Spectrum Ensures high transmission and voice quality, security
Short PN, long PN and Wash codes are used for coding
Multiple Access Code Division:Improve frequency reuse and guarantee large capacity
Soft Handoff Seamless communication without call dropping
High communication quality
Power Control
Ensure optimum power level with least interference to other channels,reducingNear and Far Effectand thus increasing capacity
Low radiation and longer battery usage time Diversity Receiver (Rake Receiver)
Achieve signal gain and avoidMulti-path Effect
Voice Activation
Lower transmitting power and low speed
Voice Coding
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Spread Spectrum-Basis for CDMA Technology
Definition:
Spread spectrum technique ,employ a transmission bandwidth that is
several orders of magnitude greater than the minimum required signal
bandwidth.
Theoretic Basis: Shannons Law
C=Blog2(1+S/N)
C: Channel Capacity B: bandwidth S/N: signal to noise ratio
Conclusion: When C is a fixed value, S/N is a reciprocal ratio of B
Another techniques for Spread Spectrum:
DSSS: Direct Sequence Spread Spectrum
FHSS: Frequency Hopping Spread Spectrum
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Traditional radio communication systems transmit datausing the minimum bandwidth required to carry it as a
narrowband signal, e.g. FDMA and TDMA systems.
TRADITIONAL COMMUNICATIONS SYSTEM
Slow
InformationSent
TX
Slow
InformationRecovered
RX
NarrowbandSignal
Spread Spectrum Principles
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SHANON Formula
C = Blog2(1+S/N)
Spread Spectrum Principles (Continued)
Where,C is capacity of channel, b/s
B is signal bandwidth, Hz
S is average power for signal, W
N is average power for noise, W
It is the basic principle and theory for spread spectrumcommunications.
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The de-spreading gives substantial gain proportional tothe bandwidth of the spread-spectrum signal
The gain can be used to increase system performanceand range, or allow multiple coded users, or both
Processing Gain For SPREAD-SPECTRUM SYSTEM
Gp=10log (B/Bm)Where,
Gp is processing gain, dB
B is spreading signal bandwidth, Hz
Bm is original signal bandwith, Hz
E.g., it is 21 dB for IS-95A CDMA system.
Spread Spectrum Principles (Continued)
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Basic Spreading & DeSpreading Example
User Data Spread, Sent, Recovered
XORExclusive-OR
Gate
1
1
Input A: Received Signal
Input B: Spreading Code
Output: User Original Data
Input A: User Data
Input B: Spreading Code
Spread Spectrum Signal
XORExclusive-OR
Gate
At Originating Site:
Input A: Users Data @ 19,200bits/second
Input B: Walsh Code #23 @
1.2288 Mcps Output: Spread spectrum signal
At Destination Site:
Input A: Received spreadspectrum signal
Input B: Walsh Code #23 @1.2288 Mcps
Output: Users Data @ 19,200bits/second just as originally sent
via air interface
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Channel Coding
SS
Carrier
Modulation
DS-PN
Radio
ChannelSource
Coding
Channel
DecodingCarrier
Demodulation
DS-PN
Source
Decoding
Transmit Receive
Antenna
Channel
Decoding
Carrier
Demodulation
DS-PN
Radio
Channel
Source
Decoding
Channel
CodingSS
Carrier
Modulation
DS-PN
Source
Coding
TransmitReceive
Antenna
A B
Spread Spectrum1
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f
Sf
f0
Signal Frequency Before Decoding
f
Sf
f0Signal Frequency Before SS
Signal
Signal
Noise
f
Sf
f0
Signal Frequency after SS
Signal
f
Sf
f0
Signal Frequency After Decoding
Signal
Noise
Signal Pulse Noise Other Noise
Spread Spectrum (2)
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Spread Spectrum (3)- Spreading Codes
Spreading Code Rate: 1.2288Mc/s
Multi-path separation,(delay:1--100s)
Delay1 MHZ Multiples of base band rate 9.6 kbps
Spreading Codes
Forward : Walsh code Reverse: Long PN Codes (242-1)
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Spread Spectrum (4)
Advantages:
Avoid interference arising from jammingsignal or multi-path effects
SS and demodulation, noise is suppressed
and filtered
Security: difficult to detect
Privacy: Difficult to demodulate
Multiple Access: Improve Frequency Reuse
Enlarge Capacity
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CDMA Spreading Principle
Any data bitstream can be combined with a spreading sequence The resulting signal can be de-spreading and the data stream
recovered if the original spreading sequence is available andproperly timed
After de-spreading, the original data stream is recovered intact
Note - The spread sequences actually shown are icons, not accurate or toscale
ORIGINATING SITE DESTINATION
SpreadingSequence
SpreadingSequence
Input
Data
Recovered
Data
Spread Data Stream
Single spreading sequence are reversible
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CDMA Spreading Principle (Continued)
Multiple spreading sequences can be applied in succession and thenreapplied in opposite order, to recover the original data stream the spreading sequences can have different desired properties
All spreading sequences originally used must be available in propersynchronization at the recovering destination
Note - The spread sequences actually shown are icons, not accurate or toscale
Multiple successivesequence are reversible
SpreadingSequence
A
SpreadingSequence
B
SpreadingSequence
C
SpreadingSequence
C
SpreadingSequence
B
SpreadingSequence
A
Input
DataX
Recovered
DataX
X+A X+A+B X+A+B+C X+A+B X+A
Spread-Spectrum Chip StreamsORIGINATING SITE DESTINATION
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Code Division Multiple Access (1)
Orthogonal Walsh function
Forward link: Spreading and building of coded channels
Reverse link: orthogonal modulation of MS signal
Long PN Code ( cycle length: 2421) Forward link: identification of MS
Reverse link: Spreading and user MS identification
Short PN Code (cycle length: 215-1) Forward and Reverse link: both for orthogonal QPSK
modulation, with different phase for different BS and identical
phase for different MS (0 offset)
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Division of Channels Forward Link
Pilot: continuous transmission, for synchronization and handoff, no message
Synchronization : for the mobile to capture initial timing or synchronization
when initializing
Paging Channel: for the transmission of system message and paging
message, registration and traffic channel assignment
Forward Traffic Channel: transmission of voice, data and related signalling
Reverse Link
Access : used for initiating communication with BS and responding to
paging message ( 1 Paging channel corresponds to up to32 access )
Reverse Traffic: for transmission of user and signalling information during
call establishment.
Code Division Multiple Access (2)
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Code Division Multiple Access (3)
Traffic
User trafficMSpower control
Sub-channel
Forward CDMAChannels
Pilot Sync. Paging Paging Traffic Traffic
W0 W32 W1 W7 W8 W62 W63
Reverse CDMAChannels
Access Access Traffic Traffic Traffic
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CDMA Spreading Code
64Sequences, each 64chips long
Each Walsh Code isprecisely Orthogonalwith respect to all
other Walsh Codes
Walsh Code
EXAMPLE:
Correlation of Walsh Code #23 with Walsh Code #59
#23 0110100101101001100101101001011001101001011010011001011010010110
#59 0110011010011001100110010110011010011001011001100110011010011001
Sum 0000111111110000000011111111000011110000000011111111000000001111
Correlation Results: 32 1, 32 0: Orthogonal!!
Unique Properties:
Mutual Orthogonality
WALSH CODES# --------------------- ------------- 64-Chip Sequence ----------------------------------------- -
0 0000000000000000000000000000000000000000000000000000000000000000
1 01010101010101010101010101010101010101010101010101010101010101012 00110011001100110011001100110011001100110011001100110011001100113 01100110011001100110011001100110011001100110011001100110011001104 00001111000011110000111100001111000011110000111100001111000011115 01011010010110100101101001011010010110100101101001011010010110106 00111100001111000011110000111100001111000011110000111100001111007 01101001011010010110100101101001011010010110100101101001011010018 00000000111111110000000011111111000000001111111100000000111111119 0101010110101010010101011010101001010101101010100101010110101010
10 001100111100110000110011110011000011001111001100001100111100110011 011001101001100101100110100110010110011010011001011001101001100112 000011111111000000001111111100000000111111110000000011111111000013 010110101010010101011010101001010101101010100101010110101010010114 001111001100001100111100110000110011110011000011001111001100001115 011010011001011001101001100101100110100110010110011010011001011016 000000000000000011111111111111110000000000000000111111111111111117 010101010101010110101010101010100101010101010101101010101010101018 001100110011001111001100110011000011001100110011110011001100110019 011001100110011010011001100110010110011001100110100110011001100120 000011110000111111110000111100000000111100001111111100001111000021 0101101001011010101001011010010101011010010110101010010110100101
22 001111000011110011000011110000110011110000111100110000111100001123 011010010110100110010110100101100110100101101001100101101001011024 000000001111111111111111000000000000000011111111111111110000000025 010101011010101010101010010101010101010110101010101010100101010126 001100111100110011001100001100110011001111001100110011000011001127 011001101001100110011001011001100110011010011001100110010110011028 000011111111000011110000000011110000111111110000111100000000111129 010110101010010110100101010110100101101010100101101001010101101030 001111001100001111000011001111000011110011000011110000110011110031 011010011001011010010110011010010110100110010110100101100110100132 000000000000000000000000000000001111111111111111111111111111111133 010101010101010101010101010101011010101010101010101010101010101034 001100110011001100110011001100111100110011001100110011001100110035 011001100110011001100110011001101001100110011001100110011001100136 000011110000111100001111000011111111000011110000111100001111000037 010110100101101001011010010110101010010110100101101001011010010138 001111000011110000111100001111001100001111000011110000111100001139 011010010110100101101001011010011001011010010110100101101001011040 000000001111111100000000111111111111111100000000111111110000000041 010101011010101001010101101010101010101001010101101010100101010142 0011001111001100001100111100110011001100001100111100110000110011
43 011001101001100101100110100110011001100101100110100110010110011044 000011111111000000001111111100001111000000001111111100000000111145 010110101010010101011010101001011010010101011010101001010101101046 001111001100001100111100110000111100001100111100110000110011110047 011010011001011001101001100101101001011001101001100101100110100148 000000000000000011111111111111111111111111111111000000000000000049 010101010101010110101010101010101010101010101010010101010101010150 001100110011001111001100110011001100110011001100001100110011001151 011001100110011010011001100110011001100110011001011001100110011052 000011110000111111110000111100001111000011110000000011110000111153 010110100101101010100101101001011010010110100101010110100101101054 001111000011110011000011110000111100001111000011001111000011110055 011010010110100110010110100101101001011010010110011010010110100156 000000001111111111111111000000001111111100000000000000001111111157 010101011010101010101010010101011010101001010101010101011010101058 001100111100110011001100001100111100110000110011001100111100110059 011001101001100110011001011001101001100101100110011001101001100160 000011111111000011110000000011111111000000001111000011111111000061 010110101010010110100101010110101010010101011010010110101010010162 001111001100001111000011001111001100001100111100001111001100001163 0110100110010110100101100110100110010110011010010110100110010110
Hn Hn
H2n = ___Hn Hn
0110
1100
1010
0000
10
000
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CDMA Spreading Code(Continued)
Every Users Long Code is 242 chips long Generated at 1.2288 Mcps, it requires 41.4 days to complete Each phone has a world-unique User Long Code generated using its 32-bit
ESN, an Operator-Definable 10-bit User Mask, and the current long codestate expressed as a 42-bit binary number
Users Long Codes are not exactly orthogonal but are sufficiently different topermit reliable decoding on the reverse link
Long Code( G E N E R A T E D I N T A P - S UMME D S H I F T T E R )R E G I S
1 1 0 0 0 1 1 0 0 0 P E RMU T E D E S N+
=0
Long CodeState
(@ 1.2288 MCPS)
Public Long CodeMask (STATIC)
User Long Code(@1.2288 MCPS)
one chip at a time
S UM
Modulo-2 Addition
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CDMA Spreading Code(Continued)
Short Code The PN Sequence is 32,768(215)
chips long
a two-dimensional binarysector with distinct I and Q
component sequences, each32,768 chips long
The PN Sequence (and anysequence) correlates with itselfperfectly if compared at a timingoffset of 0 chips
The Short PN Sequence is special:Orthogonal compared with itselfusing any possible timing offsetother than 0
IQ
IQIQ
Total Correlation: All bits = 0
Short PN Sequence vs. Itself @ 0 Offset
IQIQ
Orthogonal: 16,384 1 + 16,384 0
Short PN Sequence vs. Itself @ Any Offset
Unique Properties:
32,768 chips long26.666 ms.
(75 repetitions in 2 sec.)
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CDMA Spreading Code(Continued)
Summary of Characteristics & Functions
Walsh Code
Short Code
Long Code
Type of Sequence
MutuallyOrthogonal
Orthogonal withitself at any timeshift value
near-orthogonalif shifted
Special Properties
64
1
1
HowMany
64 chips1/19,200 sec.
32,768 chips26-2/3 mS
75x in 2 sec.
242 chips~40 days
Length
Modulation
Quadrature Spreading(Zero offset)
Distinguish users, allowrecovery
Reverse LinkFunction
User identitywithin logic
channel
Distinguish Cells& Sectors
Data Scramblingto distinguish
users
Forward LinkFunction
Each CDMA spreading sequence is used for a specificpurpose on the forward link and a different purpose onthe reverse link
The sequences are used to form code channels forusers in both directions
Cell
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Forward CDMA channel modulation process
User data from
BS in 9600bps
4800bps 2400bps
1200bps
Convolutional
Encoder and
Repetition
interleaver
r=1/2,K=9
19.2kbps
Datascrambling
MUX
Power
contrl bit
Walsh code
Long code
generator
Long code
for userDecimator
1.2288Mcps
Decimator
4
800Hz
Base
band
Filter
Base
band
Filter
I Q
I-channel Pilot PN Sequence
Q- channel Pilot PN Sequence
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Reverse IS-95 channel modulation for a single user
Information
Bit
9600bps
4800bps
2400bps
1200bps
Conver
lutional
Encoder and
Repetition
r=1/3 K=9
Block
Inter-
leaver
Code
Symbol
28.8kbps
64-aryOrtho-
gonal
Modulator
Code
Symbol
DataBurst
Rand-
omizer
Walsh
chip
307.2
kcps
Long Code Generator
Long Code Mask
for user PN chip
1.2288Mcps
Base-
band
Filter
I-channel
PN chip
DBaseband
Filter
I(t)
Q(t)Q-channel
1/2 PN chip Delay=406.9ns
IQ :Zero-offset Pilot Sequence
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41 33 32 28 27 25 24 9 8 0
110001111 ACN PCN BASE_ID PILOT_PN
ACN:number of access channel;PCN:number of paging chBASE_ID, PILOT_PN.
Access channel long code mask:
Public long code mask:
41 32 31 0
1100011000 Permuted ESN
What is mask ?
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Different approaches to bandwidth problem
CDMA
TDMAFDMA
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Coding Process on CDMA Forward Channels
Each user is assigned one of the 64 Walsh Codes and their traffic is mixed with theWalsh code to establish a dedicated code channel Each Users Long code is applied incidentally for data scrambling
All user code signals are then analog-summed to produce one composite waveform The composite waveform is the combined with the PN sequence using a specific
offset to uniquely identify this cell sector
BTSPilot Walsh 0
Walsh 19
Paging Walsh 1
Walsh 6
Walsh 11
Walsh 20
Sync Walsh 32
Walsh 42
Walsh 37
Walsh 41
Walsh 55
Walsh 60
Walsh 55
PN OFFSET 372
PN OFFSET 116BTS
PN OFFSET 226BTS
PN OFFSET 511BTS
ANALOG
SUM
PN
372
WALSH
19
x
x
x
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Functions of the CDMA Forward channels
Pilot Walsh 0
Walsh 19
Paging Walsh 1
Walsh 6
Walsh 11
Walsh 20
Sync Walsh 32
Walsh 42
Walsh 37
Walsh 41
Walsh 55
Walsh 60
Walsh 55
PILOT: WALSH CODE 0 The Pilot is a structural beacon which does
not contain a character stream. It is a timingsource used in system acquisition and as ameasurement device during handoffs
SYNC: WALSH CODE 32
This carries a data stream of systemidentification and parameter informationused by mobiles during system acquisition
PAGING: WALSH CODES 1 up to 7
There can be from one to seven pagingchannels as determined by capacity needs.They carry pages, system parameters
information, and call setup ordersTRAFFIC: any remaining WALSH codes
The traffic channels are assigned toindividual users to carry call traffic. Allremaining Walsh codes are available,subject to overall capacity limited by noise
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Analog Summing for Multiple Access
This simplified demonstration shows analog summing using only four abbreviatedWalsh codes, each 4 bits long. Four users are talking.
Each user signal is XORed with their assigned Walsh code, and the results areanalog-summed and sent over a single medium, much like in CDMA.
At the other end, the Walsh codes are applied to recover each user data.
X
X
X
X
User A
User B
User C
User D
User A
User B
User C
User D
Walsh 0
Walsh 1
Walsh 2
Walsh 3
Walsh 0
Walsh 1
Walsh 2
Walsh 3
A + 0
B + 1
C + 2
D + 3
Analog
Summing
Input Bits
#1 #2
Spreading De-SpreadingPower
IntegrationOutput Bits
#1 #2
InCDMA,this isthe air
interface
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Coding Process on CDMA Reverse Channels
Each mobile is uniquely identified by an offset of the User Long Code, which it
generates internallyAll mobiles transmit simultaneously on the same 1.25-MHz wide frequency band
Any nearby BTS can dedicate a channel element to the mobile and successfullyextract its signal
Mobiles also use the other CDMA spreading sequences, but not for channel-identifying purposes
Short PN Sequence is used to achieve phase modulationWalsh Codes are used as symbols to give ultra-reliable communications recovery
at the BTS
User Long CodeBTS BSC MSC
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Functions of the CDMA Reverse channels
ACCESS: It is used by mobiles not yet in a call totransmit registration requests, call setup requests,
page responses, order responses, and other signalling
information
an access channel is defined by a special public
long code mask
Access channels are paired with Paging Channels.
There can be up to 32 access channels per paging
channel
TRAFFIC:It is used by individual users during theiractual calls to transmit traffic to the BTS
a traffic channel is defined by a specific UserLong Code
there are as many reverse Traffic Channels as
there are CDMA phones in the world
911
REG
BTS
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Technical Advantages of CDMA Technology
For the Telecom Service Provider
High Efficiency of Frequency Utilization
Large Capacity Network
Simple Frequency Planning
Compatible with Analog Mobile Network Smooth migration to 3G
For the Subscriber
Crystal-clear Voice Quality
Good Anti-jamming Inter system soft handoff reduces call dropping
Low radiation and Long Standby time (long battery duration)
Reliable Security
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Development of CDMA Technology
CDMA One : core technology IS95 :
IS 95A: only 1 spreading code for 1 traffic channel, 14.4 Kbps
1980, First field test by Qualcomm
1990, first version of CDMA UM interface standard by Qualcomm
1995, N-CDMA standard IS-95A by TIA
IS 95B : max. 8 codes for 1 traffic channel (one user for high-speed
packet data service
enhanced Air interface, hardware compatible with IS-95A
64 kbps dual way data service ,
CDMA 2000 :144K/384K/2M bps
CDMA 2000-1X: 144 kbps
CDMA 2000-3X: 2 Mbps (CDMA 2000-1X-EV)
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Contents
Overview of Mobile Communications
Technical Features of CDMA
Dynamics of 3 G ( the 3rd GenerationCommunications System)
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Dynamics of 3G
Background
Higher demand of QoS
Seamless internal roaming, wideband, flexible
Large capacity, frequency resource usage
IMT-2000
Naming
commercial use expected in 2002 First phase frequency band around 2 G HZ.
Requirements
QoS: voice/coverage, transmission/delay(BER
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Dynamics of 3G
UIM MT RAN CNOther CN of
IMT-2000
family
UIM: user identity module
MT: mobile terminal
RAN: radio access network
CN: core network
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RTT: Radio Transmission Technology Proposed standards: 10 (FDD: 8 , TDD 5)
Dynamics of 3G
No. RTT Proposed Duplex Proposer
1 J: WCDMA FDD, TDD Japan: ARIB
2 ETSIUTRA - UMTS FDD, TDD Europe: ETSI
3 WIMS W - CDMA FDD US: TIA
4 WCDMA/NA FDD US: TIPI
5 Global CDMA II FDD SK: TTA
6 TD - SCDMA TDD China: CATT
7 CDMA 2000 FDD, TDD US: TIA
8 Global CDMA I FDD SK: TTA
9 UWC - 136 FDD US: TIA
10 DPDECT TDD Europe: ETSI
1. 15 : similar to WCDMA, harmonization forms 3GPP WCDMA
2. 78 similar to CDMA 2000, harmonization forms 3GPP2 CDMA 2000
3. 9 : UWC 136, based on IS 136 TDMA (D-AMPS)
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Dynamics of 3G
Wireless Access Network Various standards:
W-CDMA FDD, W-CDMA TDD(TD-SCDMA), CDMA-
2000 Multi-carrier, UWC-136 TDMA
Widely accepted standards:
CDMA 2000
W-CDMA
UWC-136
Core Network
ANSI TIA/EIA-41 MAP GSM MAP
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Comparison Between W-CDMA & CDMA 2000
Item W-CDMA CDMA-2000
Min. Band Width
SS technique Single Carrier DS Multi-carrier Or DS
Code chip rate 4.096Mcpsreduced to3.84Mc
N1.2288Mcps
Sync. Between
BS
Async, Sync. Can be selected Sync. (GPS)
Frame length 10ms 20ms
Voice Coding Fixed rate Variable rate
Power Control
Rate
1600Hz 800Hz
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Dynamics of 3 G
Wireless Access Standards Development from 2 G to 3 G
GSM
GSM-----GRPS and EDGE (up to 384 kbps)---W-CDMA (5 MHZ)
CDMA
IS 95A/B(14.4-64 kbps) cdma2000-1X (144 kbps) cdma2000-3X
cdma2000-1X-EV
TDMA (TIA-EIA-136)
IS136 IS-136+(TIA/EIA 136-A/B) TDMA/EDGE/GRPS(384kbps) IS137
2.5 G 3 G
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Consolidation of ITU IMT-2000Very complicated task Technical difference:
SS, code chip rate, Sync. Mode, Pilot, core network(GSM-MAP and IS-
41)
Conflict of interest of various parties involved current market status of mobile communications, IPR, interest of service
provider and manufacturers
3GPP1998-12 Initiated by ETSI and joined by ARIBTCCTITTA
CN: GSM-MAP, RAN: UTRA 3GPP21999-1
Initiated by TIA/ANSI and joined by ARIB, TTC, TTA
CN: ANSI/IS-41, RAN: cdma2000
Dynamics of 3 G
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Typical IS95A Network Structure of ZTE
MSC/
VLR
HLR/AUC
MS
Abis
Abis
Abis
PSTN/PLMN
BSC
BSC
Abis
BSC
A-ISO2 .x
Um IS41D/E
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Evolution from 2G System to 3G System
HDR
IS-95Acdma2000-3x
1X-EV
IS-95B
cdma2000-1x
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CDMA Network Evolution of ZTE
IS95A Cdma 2000 1X
Transition
methods
Data service rate
Adopts IOS4.0 for A Interface
144K 2M
Smooth evolution
to 3G
MSS evolves from current Circuit Switching
mode to full IP mode
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CDMA2000-1X Network Structure
MSC/
VLR
HLR/AUC
2G BTS
3G BTS (1X) or 2G
BTS+upgrade
2G/3G
MS
Abis
Abis
Abis
PSTN/PLMN
2G BSC+upgrade or
3G BSC/ PCF (1X)
Internet
PDSN
HAAAA
server
router router
Ethernet
ATM
2G BTS
2G BSC
Abis
BSM
E1Um
IS95
Um
IS2000 E1STM-1
E1
STM-1
Ethernet
2G BSC+upgrade or
3G BSC/ PCF (1X)
3G BTS (1X) or 2G
BTS+upgrade
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The end !