CDMA 2000 Principle Issue4.0

Objectives
After this presentation, you will be familiar with:
 the development of mobile communication system
 the structure of CDMA2000 network
 the number planning in CDMA2000 network
 the techniques used by CDMA system including:
source coding, channel coding, interleaving, scrambling,
spreading and modulation etc.
power control, soft handoff, RAKE receiver
F-PCH,F-PICH,F-SYNCH,F-FCH,F-SCH,R-ACH,R-PICH
 Long code, short code and Walsh code

Course Organization
Chapter 1: Introduction
Chapter 2: CDMA Techniques & Technologies
Chapter 3: CDMA Air Interface
Chapter 4: CDMA Number Planning

1st
Generation
1980s (analog)
2nd
Generation
1990s (digital)
3rd
Generation
current (digital)
3G provides:
 Complete integrated service
solutions
 High bandwidth
 Unified air interface
 Best spectral efficiency and
……………… a step towards PCS
AMPS
Analog to Digital
TACS
NMT
OTHERS
GSM
CDMA
IS95
TDMA
IS-136
PDC
UMTS
WCDMA
CDMA
2000
TD-
SCDMA
Development of Mobile Communications
Introduction
Voice to Broadband

Transmission Techniques
Traffic channels: different
users are assigned unique
code and transmitted over
the same frequency band,
for example, WCDMA and
CDMA2000
FDMA
Traffic channels: different frequency bands
are allocated to different users,for example,
AMPS and TACS
Traffic channels: different time slots
are allocated to different users, for
example, DAMPS and GSM
Frequency
Time
Power
Frequency
Time
Power
Frequency
Time
Power
TDMA
CDMA
User
User
User
User
User
User
Introduction

Standards for3G
3G system
CDMA2000
3GPP2
FDD mode
WCDMA
3GPP
FDD mode
TD-SCDMA
CWTS
TDD mode
Introduction

A Comparison b/w 3G standards
WCDMA CDMA2000 TD-SCDMA
Receiver type RAKE RAKE RAKE
Close loop power
control Supported Supported Supported
Handoff Soft/hard handoff
Demodulation
mode
Coherent
Chip rate (Mcps) 3.84 N*1.2288 1.28
Transmission
diversity mode
TSTD, STTD
FBTD
OTD, STS No
Synchronization
mode
Asynchronous Synchronous Asynchronous
Core network GSM MAP ANSI-41 GSM MAP
CoherentCoherent
Soft/hard handoffSoft/hard handoff
Introduction

IS95A
9.6kbps
IS95A
115.2kbps
CDMA2000 307.2kbps
 Heavier voice
service capacity ;
 Longer period of
standby time
CDMA2000
3X
CDMA2000
1X EV
1X EV-DO
1X EV-DV
1995 1998
2000
2003
Development of CDMA
 Higher spectrum efficiency and network capacity
 Higher packet data rate and more diversified services
 Smooth transit to 3G
Introduction

Frequency Allocation In CDMA2000
Band Class 0 and Spreading Rate 1
Introduction
Transmit Frequency Band (MHz)
Block
Designator
CDMA Channel
Validity
CDMA
Channel
Number
Mobile Station Base Station
A(10MHz) Valid 1-311 825.030-834.330 870.030-879.330
B(10MHz) Valid 356-644 835.680-844.320 880.680-889.320
A’(1.5MHz) Valid 689-694 845.670-845.820 890.670-890.820
B’(2.5MHz) Valid 739-777 847.170-848.310 892.170-893.310
The transmit frequence point for Base Station is computed by:
F=870+N*0.03
N: CDMA Channel Number

Frequency Allocation In CDMA2000
Band Class 1 and Spreading Rate 1
Introduction
Transmit Frequency Band (MHz)
Block
Designator
CDMA
Channel
Validity
CDMA
Channel
Number
Mobile Station Base Station
A(15MHz) Valid 25-275 1851.250-1863.750 1931.250-1943.750
D(5MHz) Valid 325-375 1866.250-1868.750 1946.250-1948.750
B(15MHz) Valid 425-675 1871.250-1883.750 1951.250-1963.750
E(5MHz) Valid 725-775 1886.250-1888.750 1966.250-1968.750
F(5MHz) Valid 825-875 1891.250-1893.750 1971.250-1973.750
C(15MHz) Valid 925-1175 1896.250-1908.750 1976.250-1988.750
The transmit frequence point for Base Station is computed by:
F=1930+N*0.05
N: CDMA Channel Number

CDMA2000 1XNetworkStructure
MS: Mobile Station BTS: Base Transceiver Station
BSC: Base Station Controller MSC: Mobile Switching Center
HLR :Home Location Register VLR: Visitor Location Register
PCF: Packet data Control Function PDSN: Packet Data Service Node
HA: Home Agent FA: Foreign Agent
SCP: Service Control Point Radius: Remote Authentication Dial-in User Service
Abis
A1(Signaling)
A2(Traffic)
A11(Signaling)
A10(Traffic)
A3(Signaling &
Traffic)
A7(Singaling)
Introduction

Course Contents
Chapter 1 Introduction
Chapter 2 CDMA Techniques & Technologies
Chapter 3 CDMA Air Interface
Chapter 4 CDMA Number Planning

Correlation
(a)
Correlation 100% so the
functions are parallel
Correlation 0% so the
functions are orthogonal
CDMA Techniques & Technologies
+1
-1
+1
-1
(b)
+1
-1
+1

Orthogonal Function
 Orthogonal functions have zero correlation. Two binary sequences
are orthogonal if their “XOR” output contains equal number of 1’s
and 0’s
0000
0101
0101
EXAMPLE:
1010
0101
1111

Information spreading overorthogonal codes
1 0 0 1 1
0110 0110 0110 0110 0110
1001 0110 0110 1001 1001
User Input
Orthogonal
Sequence
Tx Data
+1
-1
+1
-1

Information recovery CDMA Techniques & Technologies
1 0 0 1 1
+1
-1
Rx Data
1001 0110 0110 1001 1001
0110 0110 0110 0110 0110
1111 0000 0000 1111 1111
Correct Function
? ? ? ? ?
Rx Data
1001 0110 0110 1001 1001
0101 0101 0101 0101 0101
1100 0011 0011 1100 1100
Incorrect Function

Spreading and De-spreading
information pulse interference White noise
The improvement of time-domain information rate means that the bandwidth of spectrum-domain
information is spread.
S(f) is the energy density.
f
S （ f ）
The spectrum before spreading
information
f0
The spectrum before despreading
information
Interference/noise
S （ f ）
f0 f f0
The spectrum after despreading
information
Interference/noise
S （ f ）
f
The spectrum after spreading
information
f0
S （ f ）
f

Signal flow
InterleavingSource
coding
Convolution
&
Interleaving
Scrambling Spreading Modulation
RF
transmission
Source
decoding
deinterleaving
Decovolution
&
Deinterleaving
Unscrambling De-spreading Demodulation RF receiving

Common Technical Terms
 Bit, Symbol, Chip:
 A bit is the input data which contain information
 A symbol is the output of the convolution, encoder, and the block
interleaving
 A chip is the output of spreading
 Processing Gain:
 Processing gain is the ratio of chip rate to the bit rate.
 The processing gain in IS-95 system is 128, about 21dB.
 Forward direction: Information path from base station to mobile station
 Reverse direction: Information path from mobile station to base station

In a typical duplex call, the duty ratio is less than 35%. To achieve
better capacity and low power consumption, base station reduces
its transmission power.
Source Coding
 Vocoder:
8K QCELP
13K QCELP
EVRC
 Characteristics
Support voice activity

Channel Coding
Convolution code or TURBO code is used in channel encoding
Constraint length=shift register number+1.
Encoding efficiency= (total input bits / total output symbols)
convolution encoder
Input
(bits)
Output (symbols)

Turbo Code
Turbo code is used during the transmission of large data packet.
 Characteristics of the Turbo code:
 The input information is encoded twice and the two output codes can
exchange information with each other during decoding.
 The symbol is protected not only by the neighborhood check bits, but also
by the separate Check Bits.
The performance of a Turbo code is superior to that of a convolution code.

Interleaving
The direction of the data stream
1 2 873 64 5
1 2 873 64 5
1 2 873 64 5
1 2 873 64 5
1 2 873 64 5
1 2 873 64 5
1 2 873 64 51 2 873 64 51 2 873 64 5
1 2 873 64 5
1 1 111 11 1
2 2222
7 7 777 77 7
6 6 666 66 6
3 3 333 33 3
4 4 444 44 4
1 2 873 64 51 2 873 64 55 5 555 55 5
8 8 888 88 8
interleaving
2 2 2

Out
0 0 1
1 1 0
Scrambling (M) sequence
 Two points are important here:
 Maximum number of shift register (N)
 Mask
 The period of out put sequence is 2N
-1 bits
 Only sequence offset is change when the mask is changed
 PN stands for Pseudorandom Noise sequence

Long Code
 The long code is a PN sequence with period of 242
-1chips
 The functions of a long code:
 Scramble the forward CDMA channel
 Control the insertion of power control bit
 Spread the information on the reverse CDMA channel to identify the
mobile stations

PNa
PNc
PNb
Short Code
 Short code is a PN sequence with period of 215
chips
 Sequence with different time offset is used to distinguish different
sectors
Minimum PN sequence offset used is 64 chips, that is, 512 PN
offsets are available to identify the CDMA sectors (215
/64=512).

Walsh Code
W2n=
Wn Wn
Wn Wn
W1=0
W2=
0 0
0 1
W4 =
0 0
0 1
0 0
0 1
0 0
0 1
Walsh code
64-order Walsh function is used as a spreading function and
each Walsh code is orthogonal to other.
Walsh Code is one kind of orthogonal code.
A Walsh can be presented by Wi
m
where ith
(row) is the
position and m is the order. For example, W2
4
means 0101
code in W4 matrix
1 1
1 0

 In forward direction, each symbol is spread with Walsh code
 Walsh code is used to distinguish the user in forward link
 For IS95A/B, in the reverse, every 6 symbols correspond to one Walsh code.
For example, if the symbol input is 110011,the output after spreading is W51
64
(110011=51).
 For CDMA2000, in the reverse, Walsh function is used to define the type of
channel (RC 3-9)
Walsh Code

Variable Walsh codes
64
4
8
16
32
1
2
9600 19200 38400 76800 153600 307200 614400
Data rate -bps-
W0
1 =0
W0
2=00
W1
2=01
W0
4=0000
W2
4=0011
W1
4=0101
W3
4=0110
W0
8=00000000
W4
8=00001111
W2
8=00110011
W6
8=00111100
W1
8=01010101
W5
8=01011010
W3
8=01100110
W7
8=01101001
( W0
16,W8
16)
( W4
16,W12
16)
( W2
16,W14
16)
( W6
16,W14
16)
( W1
16,W9
16)
( W5
16,W13
16)
( W3
16,W11
16)
( W7
16,W15
16)
The different Walsh codes
corresponding to different data rates

Modulation-QPSK
I
Q
I channel PN sequence
1.2288Mcps
Q channel PN sequence
1.2288Mcps
Baseband filter
Baseband filter
Cos(2pfct)
Sin(2pfct)
I(t)
Q(t)
s(t)
A
1.2288Mcps: the PN chip rate of the system
.
After being spread, all the forward channels in the same carrier are
modulated by means of QPSK(OQPSK in the reverse), converted
into simulation signals and transmitted after clustering.

Power Control
Handoff
Diversity and RAKE

PowerControl
Reverse power control
Open loop power control
Closed loop power control
− Inner loop power control: 800 Hz
− Outer loop power control
Forward power control
Message transmission mode:
− threshold transmission
− periodic transmission
Closed loop power control
.

Reverse Open Loop PowerControl
• The transmission power required by the mobile station is determined by
the following factors:
 Distance from the base station
 Load of the cell
 Circumstance of the code channels
• The transmission power of the mobile station is relative to its received
power.
BTSMobile
Reverse Open Loop
Power Control
BTS
BTS
Transmitting
Power

Reverse Closed Loop PowerControl
BTS
Power Control Bit
Eb/Nt Value FER Value
Inner Loop Power Control
Outer Loop Power Control
Change in Eb/Nt Value
BSC
BTS

Forward PowerControl
 MS measures the frame quality and informs the base station to the
result i.e. whether it is in the threshold or periodical mode. Base station
determines whether to change the forward transmitting power or not.
 In IS-95 system, the forward power control is slow but in CDMA2000
system it is fast.
Message Transmission Mode

Forward Closed Loop PowerControl
 Compared with IS-95 system, CDMA2000 the forward quick
power control is fast.
Power Control Bit
Eb/Nt Value
BTS

Handoff
Soft handoff
It is a process of establishing a link with a target sector before
breaking the link with the serving sector
Softer handoff
Like the soft handoff, but the handoff is occurred between multi-
sectors in the same base station
Hard handoff
Hard handoff occurs when the two sectors are not synchronized
or are not on the same frequency. Interruption in voice or data
communication occurs but this interruption does not effect the
user communication

Soft/SofterHandoff
• Multi-path combination in the BSC during soft handoff
• Multi-path combination in the BTS during softer handoffs
Combine all the
power from each
sector
Power received from
a single sector

Pilot Set
Active
Set
Candidate
Set
Neighbor
Set
Remaining
Set
The pilot set, corresponding to the base
station being connected
The pilot set, not in the active set but
potential to be demodulated
The pilot set, not included in the active set or
the candidate set but being possible to be
added in the candidate set
Other pilot sets
the set of the pilots having same frequency but different PN sequence offset

T_ADD,T_DROP,T_TDROP
Time
Ec/Io
Sector
A Sector
B
Guard Time(T-TDROP)
Add Threshold
(T_ADD)
DropThreshold
(T_DROP)
Soft Handoff Region
T_ADD, T_DROP and T_TDROP affect the percentage of MS in handoff.
T_ADD & T_DROP is the standards used to add or drop a pilot.
T_DROP is a timer.

Comparison Threshold
t0 t1 t2
Pilot P1
Pilot P2
Pilot P0
T_COMP×0.5dB
T_ADD
Pilot strength
P0-Strengh of Pilot P0 in Candidate Set.
P1,P2-Stength of Pilot P1,P2 in Active Set.
t0-Pilot strength Measurement Message Sent, P0>T_ADD
t1-Pilot strength Measurement Message Sent, P0>P1+T_COMP*0.5dB
t2 -Pilot strength Measurement Message Sent, P0>P2+T_COMP*0.5dB

Transition Between Pilot Sets
T_ADD
T_DROP
Pilot 1
Pilot
strength
Pilot 2
T_TDROP
Neighbor
Set
Candidate
Set
Active
Set
Neighbor
Set
TIME1 2 3 4 5 6

Transmit Diversity
 Time diversity
 Block interleaving, error-correction
 Frequency diversity
 The CDMA signal energy is distributed on the whole 1.23MHZ
bandwidth.
 Space diversity
 The introduction of twin receive antennas .
 The RAKE receivers of the mobile station and the base station can
combine the signals of different time delay.
 During a handoff, the mobile station contacts multiple base stations
and searches for the strongest frame

Transmission Diversity
 The forward transmission diversity types in CDMA2000 1X are
 TD (Transmit Diversity)
− OTD (Orthogonal Transmit Diversity)
▪ The data stream is divided into two parts, which will be
spread by the orthogonal code sequence, and
transmitted by two antennas.
− STS (Space Time Spreading)
▪ All the forward code channels are transmitted by the
multi-antennas.
▪ Spread with the quasi-orthogonal code
 Non-TD

Transmission Diversity
The Transmission Diversity Technology enhances the receive performance of MS.
Transmission
diversity
processing
Data stream 1
Data stream 2
Data stream Restoring data stream
Path 1
Path 2
Antenna 2
Antenna 1

The Principle of RAKE Receiver
RAKE antennas help to overcome on the multi-path fading and enhance
the receive performance of the system
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)

Course Contents
Chapter 1 Introduction
Chapter 2 CDMA Techniques & Technologies
Chapter 3 CDMA Air interface
Chapter 4 CDMA Number Planning

Physical Channel in IS-95A
Forward channel
 Forward Pilot Channel
 Forward Sync Channel
 Forward Paging Channel
 Forward Traffic Channel (including power control sub-
channel)
Reverse channel
 Access Channel
 Reverse Traffic Channel
CDMA Air Interface

Pilot channel
(all-zeros)
W0
64
Pilot Channel
A pilot channel:
 Assist mobile station to be connected with CDMA network
 Handles multi-path searching
 Provide the phase reference for coherent demodulation and help the mobile station
estimate the transmission power
 The mobile station measures and compares the pilot channel powers from the base
stations during the handoff
Forward pilot channel is spread over W0 and modulated with short code directly
BTS transmits the pilot channel continuously
CDMA Air Interface

ToQPSKcoder
2.4kbps 4.8kbps 4.8kbps
Code
symbol
Repetitive
code
symbol
1.2kbps
Convolution
encoder
r=1/2,K=9
symbol
repetition
Block
interleaving
Sync Ch bits
W32
64
Sync Channel
 The sync channel is used by the mobile station to synchronize with the network.
W32 is used to spread Sync Channel.
 The synchronization message includes:
− Pilot PN sequence offset: PILOT_PN
− System time: SYS_TIME
− Long code state: LC_STATE
− Paging channel rate: P_RAT
 Here note that, sync channel rate is 1200bps
CDMA Air Interface

ToQPSKcoder
Paging
channel bits
Paging channel address
mask
Long
code PN
generator
decimator
1.2288Mcps
Paging Channel
 The paging channel transmits:
− System parameters message
− Access parameters
− Neighbors list
− CDMA channels list message
 The paging channel accomplishes:
− Paging to MS
− Assign traffic channel to MS
 The frame length of a paging channel is 20ms
 W1~W7 are spared for the Paging Channels spreading
CDMA Air Interface
19.2/9.6Kbps 19.2kbps
19.2kbps
Code
symbol
9.6/4.8 kbps
Convolution
encoder
r=1/2,K=9
Symbol
repetition
Block
interleaving
19.2kbps
Repetitive
code
symbol
W1
64

Forward Traffic Channel
CDMA Air Interface
I Ch PN sequence (1.2288 Mcps)
PN 1.2288 Mcps
Repetitive
symbol
19.2kbps
8.6kbps
9.6kbps
4.8kbps
2.4kbps
1.2kbps
Add frame
quality indicator
bits(12,10,8,6)
Add 8
encoded tail
bits
Convolution
encoder
r=1/2,K=9
Symbol
repetition
Forward traffic
channal
(172/80/40
or
16bits/frame
)
Block
interleaver
19.2kbps
MUX
Long code
generator
Power control bits
Q Ch PN sequence (1.2288 Mcps)
Baseband
filter
I(t)
Q(t)
decimator
+
∑QPSK Modulation
4.0kbps
2.0kbps
0.8kbps
19.2ksybps
9.6ksybps
4.8ksybps
2.4ksybps
Sin(2pfct)
Cos(2pfct)
is used to transmit data and signaling information.
Walsh code
decimator
+
+
Baseband
filter
+
+

Reverse Access Channel
used by MS to initiate communication or respond to Paging Channel
CDMA Air Interface
4.8 kbps
(307.2kbps)
PN chips
1.2288 McpsOrthogonal spreading
Repetitive
symbol
8.8 kbps
Code
symbol
14.4 kbps4.4 kbps 4.8 kbpsAdd 8
encoder tail
bits
Convolution
encoder
r=1/3,K=9
Symbol
repetitionAccess
channel
(80
bits/frame)
Block
interleaving
28.8 kbps
Data burst
randomizer
Long code
PN
generator
Frame rate
Long code mask
Repetitive
symbol
Walsh code
Baseband
filter
I(t)
Q(t)
∑
QPSK Modulation
Sin(2pfct)
Cos(2pfct)
+
+
Baseband
filter
+
+
1/2 PN chips Delayed
time=406.9ns

Reverse Traffic Channel CDMA Air Interface
used to transmit data and signaling information
8.6kbps
9.6kbps
4.8kbps
2.4kbps
1.2kbps
Add frame
quality indicator
bits(12,10,8,6)
Add 8
encoded tail
bits
convolution
encoder
r=1/3,K=9
Symbol
repetition
Reverse traffic
channel
(172/80/40 or
16
bits/frame)
Block
interleaver
4.0kbps
2.0kbps
0.8kbps
28.8Ksybps
14.4Ksybps
7.2Ksybps
3.6Ksybps
4.8 kbps
(307.2kbps)
PN chips
1.2288 Mcps
Orthogonal spreading
Data burst
randomizer
Long code
PN
generator
Frame rate
Long code mask
Walsh code
Baseband
filter
I(t)
Q(t)
∑
QPSK Modulation
Sin(2pfct)
Cos(2pfct)
+
+
Baseband
filter
+
+
1/2 PN chips Delayed
time=406.9ns

Initialization of the MS
 Synchronous Channel message contains the LC_STATE, SYS_TIME,
P_RAT, and synchronizes with the system.
CDMA Air Interface
BTS
Pilot channel
Synchronous channel
Paging channel
Access channel

CDMA2000 Forward Channel
Forward CDMA2000 channel
F-CACH F-CPCCH F-PICH F-CCCH
F-DCCH F-FCH
F-PC F-SCCH F-SCH
F-PICH F-TDPICH F-APICH F-ATDPICH
F-SYNCH F-TCH F-BCH F-PCH F-QPCH
subchannel (RC1~2) (RC3~9)
Note: Only the channels with black color are being implemented in
Huawei equipment. The function of F-PICH, F-SYNCH, F-FCH, F-PC, F-
SCCH, F-PCH are the same as those of IS95. We will only discuss F-SCH,
F-QPCH F-DCCH in the following slides.
CDMA Air Interface

Forward channel
These channels are newly
defined in CDMA2000 system.
CDMA physical channels are classified in common channels and dedicated channels:
Common physical channels:
Forward Pilot Channel(F-PICH)
Forward Synchronous Channel(F-SYNC)
Forward Paging Channel(F-PCH)
Forward Broadcast Control Channel(F-BCCH)
Forward Quick Paging Channel(F-QPCH){not compatible wid is95}
Forward Common Power Control Channel(F-CPCCH)
Forward Common Assignment Channel(F-CACH)
Forward Common Control Channel(F-CCCH)
These channels are compatible
with IS-95 system
Dedicated physical channel:
Forward Dedicated Control Channel(F-DCCH)
Forward Fundamental Channel(F-FCH)
Forward Supplemental Channel(F-SCH)
These channels are used to establish the connection between a base station and a
specific mobile station.
The CDMA2000 system adopts multiple data rates and the different combinations of
channels can achieve a performance superior to that in IS-95 system.
CDMA Air Interface

F-QPCH
 It transmits OOK-modulated signal which can be demodulated by MS
simply and rapidly.
 The channel adopts 80ms as a QPCH timeslot. Each timeslot is divided into
paging indicators, configuration change indicators and broadcast
indicators, all of which are utilized to inform the MS whether to receive
paging message, broadcast message or system parameters in the next F-
PCH.
 Rapid and simple demodulation. MS no need to monitor F-PCH for long
time, so the standby time is prolonged.
CDMA Air Interface

F-SCH
 F-SCH is typically used for high speed data
applications, while F-FCH is used for common voice
and low speed data application.
 When a data call is established, firstly, F-FCH will be
allocated to the user. If the speed of data for user
exceeds 9.6kbps, F-SCH will be allocated.
CDMA Air Interface

F-DCCH
 It is used for the transmission of specific user signaling
information during a call.
 Each forward traffic channel may contain one F-DCCH.
 Support 5ms frame.
 Support discontinuous transmission.
CDMA Air Interface

Forward Radio Configuration (RC)
Radio Configuration(RC):
A set of Forward Traffic channel and Reverse Traffic Channel transmission
formats that are characterized by physical parameters such as data rates,
modulation characteristics, and spreading rate.
Spreading Rate: Equivalent to chips rate, e.g., 1.2288Mcps.
Radio
Configuration
Spreading
Rate
Max Data Rate*
(kbps)
Effective FEC
Code Rate
OTD
Allowed
FEC Encoding Modulation
1** 1 9.6 1/2 No Conv. BPSK
2** 1 14.4 3/4 No Conv BPSK
3 1 153.6 1/4 Yes Conv and Turbo QPSK
8 3 460.8 1/4 or 1/3 Yes Conv and Turbo QPSK
9 3 1036.8 1/2or 1/3 Yes Conv and Turbo QPSK
CDMA Air Interface

Reverse Channel
Reverse CDMA2000 channel
R-ACH
R-TCH
operation
(RC1~2)
R-EACH
operation
R-CCCH
operation
R-SCCH
R-FCH
R-TCH
operation
(RC3~6)
R-EACH
R-PICH
R-CCCH
R-PICH
R-DCCH
R-PICH
0~7 0~1
R-SCH
R-FCH
0~2
0~1
subchannel
R-PC
Only the channels in dark color are used in Huawei
equipment. The function of R-ACH,R-FCH,R-SCCH
are the same as those in IS95. We will only discuss
R-PICH,R-SCH in the following slides.
CDMA Air Interface

Types of Reverse Channel
 Reverse channel includes reverse common channel and reverse
dedicated channel.
 Reverse common channel:
 Reverse Access Channel(R-ACH)
 Reverse Enhanced Access Channel(R-EACH)
 Reverse Common Control Channel(R-CCCH)
 Reverse Dedicated Channel
 Reverse Pilot Channel(R-PICH)
 Reverse Dedicated Control Channel(R-DCCH)
 Reverse Fundamental Channel(R-FCH)
 Reverse Supplemental Channel(R-SCH)
 Reverse Supplemental Code Channel (R-SCCH)
CDMA Air Interface

MUX A
Pilot( all '0's)
Power Control Bit
N is the Spreading Rate number
Pilot Power
Control
Power Control Group
= 1536 NPN Chips
384 NPN Chips
Reverse Pilot Channel
R-PICH
 The Function of Reverse Pilot Channel
 Initialization
 Tracing
 Reverse Coherent Demodulation
 Power Control Measurement
 Base station enhances the received
performance and increases the capacity by
means of coherent demodulation of the Reverse
Pilot Channel.
CDMA Air Interface

Reverse Channels
 Fundamental Channel:
 Fundamental Channel is used for the transmission of user information
to the base station during a call, and can be used to transmit defaulted
voice services as an independent Traffic Channel.
 Dedicated Control Channel
 The Dedicated Control Channel is used for the transmission of user
and signaling information to a base station during a call.
 Supplemental Channel/Supplemental Code Channel
 These channels are used for the transmission of user information,
mainly data services, to the MS. The Reverse Traffic Channel contains
up to two supplemental channels and up to seven supplemental code
channels.
CDMA Air Interface

Reverse Radio Configuration (RC)
RC: Radio Configuration
RC1~RC2:IS-95A/B
RC3~RC4:CDMA2000 1X
RC5~RC6: CDMA2000 3x
Radio
Configuration
Spreading
Rate
Max Data Rate*
(kbps)
Effective FEC
Code Rate
OTD
Allowed
FEC Encoding Modulation
1** 1 9.6 1/3 No Conv 64-ary ortho
2** 1 14.4 1/2 No Conv 64-ary ortho
3 1 153.6 1/4 Yes Conv or Turbo BPSK
(307.2) (1/2)
4 1 230.4 3.8 Yes Conv or Turbo BPSK
(614.4) (1/3)
(1036.8) (1/2)
** Same as IS95
CDMA Air Interface

RC 1
RC 2
RC 3
RC 4
RC 5
RC 1
RC 2
RC 3
RC 4
RC 5
RC 3
RC 4
RC 4
RC 3
F-FCHRCs
R-DCCH/SCHRCsF-DCCH/SCHRCs
R-FCHRCs
RC Combination Regulation
 RC1 and RC2 corresponds respectively to
rate set 1 and rate set 2 in IS- 95A/B system.
 CDMA2000 Forward RC: RC1~RC5
Reverse RC: RC1~RC4
 Rules:
 Forward RC1, Reverse RC1
 Forward RC3 or RC4,Reverse RC3
CDMA Air Interface

Definition of Coverage Areas
Location area
MSC area
PLMN area
Service area
Sector
area
CDMA Number Planning
Cell area

Parameters Involved
In a CDMA system, the following parameters are defined to
identify a user and his location:
MIN/IMSI
 MDN
 ESN
 TLDN
 SID/NID
 LAI
 GCI
 SIN
 SSN

MIN/IMSI
Mobile subscriber identity/international mobile subscriber identity
For example, 0907550001/460030907550001
Not more than 15 digits
3 digits 2 digits
IMSI
MCC MNC MSIN
NMSI

MDN
CC + MAC + H 0
H1
H 2
H 3 + ABCD
International mobile subscriber DN
National valid mobile subscriber number
Mobile directory number
For example, 8613307550001

ESN
A unique Electronic Serial Number (ESN) is used to identify single
MS. An ESN includes 32 bits and has the following structure:
31......24 23......18 17......0 bit
Manufacturer’s number retained equipment SN
For example, FD 03 78 0A (the 10th Motorola 378 mobile phone)
The equipment serial number is allocated by a manufacturer.

TLDN
+CC MAC H0H 1H2 ABC+ ++44
Temporary local directory number
For example, 8613344755001

SID/NID
MSCID (Exchange Identity)
= System Identity (SID) + Exchange number (SWIN)
is used to represent a certain set of equipment in an
NSS network. For example,
Unicom CDMA Shenzhen MSC is labeled as 3755+01

Location Area Identity (LAI)
 PAGING message is broadcast within a local area, the size of which depends on
traffic, paging bearer capability, signaling flow , etc.
 Format: MCC+MNC+LAC
 MCC: Mobile Country Code, 3 digits. For example, China is 460.
 MNC: Mobile Network Code, 2 digits. For example, the MNC of
Unicom is 03.
 LAC: Location Area Code, a 2-byte-long hexadecimal BCD code.
0000 cannot be used with FFFE.
 For example, 460030100

Global Cell Identity (GCI)
 The unique ID of a cell in PLMN
 Format: LAI+CI
 CI: Cell Identity, a 2-byte-long hexadecimal BCD code, pre defined
by the engineering department. The first 3 digits and the last digit
represent the base station number and the sector number
respectively. For an omni-directional site, the last digit of CI is 0.
 For example, 4600301001230 shows base station number 123
contains an omni-directional site

Sender Identification Number(SIN)
MSC number
The MSC number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 +
1000.
HLR number
The HLR number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 +
0000.
SMC number
The SMC number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 +
2000.
SCP number
The SCP number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 +
3000.

Sub-System Number(SSN)
 SSN of MSC: 8
 SSN of VLR: 7
 SSN of HLR: 6
 SSN of AC: 10
 SSN of SMC: EE
 SSN of SCP: EF
 SSN of A interface: FE/FC
 SSN of SCCP management: 1

Review
 Chips rate: 1.2288Mcps
 IS-95A/B is a subset, RC1/RC2
 Apply the coherent demodulation to the reverse pilot channel
 Forward transmit diversity: OTD and STS
 Forward quick power control at 800HZ rate
 Improve the standby time by introducing the quick paging channel.
 Variable frames: 5ms, 20ms, 40ms and 80ms
 Introduce TURBO code into channel encoding
 The maximum rate of a physical layer is up to 307.2K
CDMA Technology

Why CDMA2000?
 Increase the system capacity
 Forward quick power control
 Forward transmit diversity: OTD,STS
 Coherent modulation applied on the pilot channel.(about
3dB)
 The introduction to Turbo code
 The stronger ability to resist interference
 The improved error-correcting encoding (applying Turbo
code in medium/high rate data transmission)

Why CDMA2000?
 Support high rate SCH, with the maximum rate of a single
channel being up to 307.2kbps.
 Improve the standby time
 Use the quick paging channel
 Forward compatibility
 Radio-frequency part
 Baseband part, such as RC

Summary
 Brief Development History of Mobile Communication
 Analog--digital--code division
 Objectives of 3G and comparison of 3 systems
 Technical features of CDMA
 Key technologies: power control, soft handoff,RAKE receiver and
cell breath
 Other technologies: source coding, channel coding, interleaving,
scrambling, spreading and modulation
 Channel structure: pilot, synchronization, paging, access and
service
 Technical features of CDMA2000 1X
 Walsh and Turbo codes

Questions
 What power control modes are there in CDMA2000 system
and how are they implemented?
 Describe the soft handoff process?
 Describe the process and functions of cell breath?
 Describe the implementation process of service channels
(forward and reverse)?
 Describe the technical features of CDMA2000?
 Describe the initialization process of a mobile phone?
 What are the functions of a long code, short code and Walsh
code in CDMA system?

CDMA 2000 Principle Issue4.0

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