3G overview final

UMTS Overview1
UMTS - 3G
1. Introduction to UMTS
2. WCDMA Wireless Technology
3. UMTS Network Architecture
4. WCDMA Air Interface Principles
5. Coverage and Capacity Principles

UMTS Overview2
UMTS Overview
Introduction to WCDMA/UMTS

UMTS Overview3
1980s 1990s 2000 +
same business, new machine new business, new machine
Services
Network
New mobile businesses
Wideband/multimedia
1 2
nd
generation
digital
st
generation
analogue 3 generation
wideband
rd
Basic mobile telephony
Evolution to 3G systemsEvolution to 3G systems

UMTS Overview4
 Consumer demand for
wideband services
 Increased network capacity
More airtime Access anytime, anyplace
Wireless postcard
Imaging
Mobile transactions
More Subscribers
UMTS DriversUMTS Drivers

UMTS Overview5
REDUCED DELAY Quicker response time with interactive services
CAPACITY Voice & Data Usage
SERVICES Streaming, Video Telephony, Mobile TV
3G Added Value3G Added Value
VOICE Improved Voice Quality
SPEED Higher bit rates: up to 384 kbps

UMTS Overview6
UMTS Spectrum AllocationUMTS Spectrum Allocation
900 MHz 880 915 925 960
EGSM
890 915 935 960
GSM
890 902.5 935 947.5
902.5 915 947.5 960
VFE GSM 900
1800 MHz 1710 1785 1805 1880
GSM
1756 1761 1763.5 1766 1851 1856 1858.5 1861
RX RX TX TX
1751 1756 1761 1763.5 1846 1851 1856 1858.5
RX RX TX TX
1850 1910 1930 1990
1900 MHz GSM/
TDMA/CDMA
1920 1980 2110 2170
UMTS/W-CDMA
MobiNil GSM 900
RX
RX
MobiNil GSM 1800
TX
TX
RX TX
TX
TX
TXRX
RX
TXRX
RX
VFE GSM 1800

UMTS Overview7
UMTS Overview
CDMA Wireless Technology

UMTS Overview8
 Old School
Divides RF spectrum to narrow segments
– FDMA Each user solely occupies his
segment
– TDMA Each user share his segment with
others in Time Domain
 New School
Divides RF spectrum to a much wider segments
− WCDMA Each user solely occupies his
segment
in both time and frequency domain
User differentiation done through
codes
Time
TDMA
• Frequency
• Time
Time
Frequency
WCDMA
• Frequency
• Code
Frequency
Code
Time
Frequency
FDMA
• Frequency
Old and New school in RF Bandwidth Utilization

UMTS Overview9
What do YOU hear...
•If you only speak Japanese?
•If you only speak English?
•If you only speak Italian?
•If you only speak Japanese, but the Japanese-
speaking person is all the way across the room?
•If you only speak Japanese, but the Spanish-
speaking person is talking very loudly?
The CDMA PartyThe CDMA Party

UMTS Overview10
In WCDMA, all cells may use the same carrier frequency but different
scrambling codes. This means no frequency planning, but scrambling code
and power planning instead!
FDMA/TDMA (reuse > 1) CDMA/WCDMA (reuse = 1)
One Cell Frequency ReuseOne Cell Frequency Reuse

UMTS Overview11
 Security
– Harder for eavesdropper to detect, jam and interfere
 Wider Scope of Applications
− Higher Bandwidth available for user gives more
varieties for supported applications
 Higher System Capacity
− Depending on unique nature of codes spreading to
distinguish different users on same carrier
Narrow Signal
Spread Spectrum Signal
Power
Frequency
Drivers behind Spread Spectrum signals

UMTS Overview12
Related Terms and Definitions
Term Definition
• Narrow Band Signal Signal occupies a relatively small bandwidth
i.e. (GSM signal has 200KHz bandwidth)
• Wide Band Signal Signal occupies relatively wide bandwidth
i.e. (WCDMA signal has 5 MHz bandwidth)
• Pseudo Noise Signal Signal has a noise like behaviour
- actual noise never repeats -
• Spreading Converting a signal with low bit rate into another
signal with much higher bit rate
• Scrambling Converting a signal into another coded version of it
keeping the same bit rate

UMTS Overview13
Related Terms and Definitions
Term Definition
• Auto Correlation Measurement for how much a signal is
related to another version of itself
• Cross Correlation Measurement for how a signal is related
to another different signal
• Orthogonal Codes Codes has Auto Correlation = 1 and
Cross Correlation = 0
• Pseudo Noise Codes Codes has Auto Correlation very close to 1 and
Cross Correlation very close to 0

UMTS Overview14






=
RateData
RateCodePN
Both signals combined
in the air interface
PN Code 1Frequency
Amplitude
Signal 1
PN Code 2
Frequency
Amplitude
Signal 2
Spread Spectrum
Processing Gain
PN Code 1 Signal 1 is reconstructed
Signal 2 looks like noise
Both signals are
received together
AT THE RECEIVER...
Two Transmitters at the same frequency
Spread Spectrum Multiple AccessSpread Spectrum Multiple Access

UMTS Overview15
• Correlation of channel codes in receiver
1 Carrier (5MHz)
Power
• Own channel correlates well, i.e. peaks (Signal)
• Other channels appear as noise (Interference)
• More users → increased interference
Signal (Eb)
Interference (No)
Power need to be adjusted to retain the Signal to Interference Ratio (SIR)
I.e. fulfilling the BLER requirements for that specific service
CDMA Rx Concept (1/2)CDMA Rx Concept (1/2)

UMTS Overview16
Spreading and Power Spectral Density
The shapes of power spectral density (Power / Hz)
are very different between b(t) and y(t).
The total power (total area) is equal, however it has
been spread over a greater bandwidth.
Spreading does not change total power.
Spreading changes how the power is
distributed over frequency
As Power of b(t) = Power of y(t)
Having fc >> fb we can now define Processing Gain G
G (processing gain) = fc/fb
fb =1/Tb (the bit rate of the input signal)
fc =1/Tc (the chip rate of the spreading code)
b
c
ty
tb
f
f
PSD
PSD
=∴
)(
)(
fcPSDfbPSD tytb .. )()( =∴

UMTS Overview17
• Digital SNR: Eb/No
b
b
R
S
E = Energy per bit (Eb)
equals the average signal power (S) divided by the data bit rate (Rb)
p
bb
b
GSNR
R
B
N
S
NR
S
N
E
⋅=





=





=
00
1
Energy per bit (Eb) - to - Noise Ratio
The Signal-to-Noise Ratio (SNR) times the SSMA Processing Gain
B
N
N =0
Noise power density (N0)
The total noise power in the signal bandwidth, divided by the signal bandwidth
CDMA Rx ConceptCDMA Rx Concept

UMTS Overview18
If the BLER requires
A Eb/No of 5dB for a
certain service and the
processing gain (Gp) is
25dB for the service,
it means a C/I down to
–20 dB is still acceptable
)Rc/Rilog(10 ⋅−=
No
Eb
I
C
Rc : Chiprate 3.84 Mc
Ri : Service bitrate
Gp
Power
+
Gp Signal (Eb)
Interference
& Noise (No)
1 Carrier (5MHz)
–20 dB
+5 dB
CDMA Rx Concept (2/2)CDMA Rx Concept (2/2)

UMTS Overview19
Input Data
+1 -1 +1
+1 -1 +1
Divide by
Code Length
Receiver and Transmitter use identical code at same time offset
+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1
PN code used
in Transmitter
x x x
+8 -8 +8
Integrate
Result
Integrate Integrate Integrate
+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1
Transmitted
Sequence
= = =
+1 +1 +1 +1 +1 +1 +1 +1 -1 –1 –1 –1 –1 –1 –1 -1 +1 +1 +1 +1 +1 +1 +1 +1
= = =
+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1
PN Code
Used in Receiver
x x x
Transmitter
Receiver
Coding Concept …Coding Concept …

UMTS Overview20
• User Input: 1 -1 -1 1 1
• Orthogonal Sequence: -111-1
• Tx Data:
• Rx Data:
• Correct Function Output:
• Incorrect Orthogonal Sequence: -11-11
• Incorrect Function Output:
Let’s work an example …Let’s work an example …

UMTS Overview22
Repeated Spreading and Scrambling
Repeated spreading and scrambling used in
• Channel identification
• Transmitter identification

UMTS Overview23
Types of Codes in WCDMA
• Two important types of digital codes are specified.
Scrambling Codes
– Pseudo Noise sequences that appear as random noise to all but the
service provider and its particular client. But they actually do repeat.
– Have very good correlation properties, but not completely orthogonal.
Channelization Codes (The Walsh functions, Orthogonal codes )
– Data channels channelization code length depends on user data rate
– Control channels channelization code length fixed by standard
– Have the highly desirable property of orthogonality

UMTS Overview24
PN Code Properties
• PN Codes: Properties
– PN codes may be generated using Linear Feedback Shift Registers
– PN Codes are repeating, defined-length blocks of 1’s and 0’s
–Approximately equal number of 1’s and 0’s
–The statistics appear randomly distributed within the block
– Good Autocorrelation and Cross-Correlation properties
–PN Code cross-correlation properties do not depend on time alignment
Example of a 32-bit (25
) PN code:
01101000110101001010011010100111

UMTS Overview25
PN Code Generation
• PN Codes: Generation using a Shift Register
D D
clock
D D
β1 β2
β3 βN
• βn values are 0 or 1 (determined by the specified “generator polynomial”)
• Maximal-length (m-sequence) has a repetitive cycle of ( 2N
- 1 ) bits
• A code of 32,768 bits can be replicated using only a 15-bit “key”
1010010010001110101...

UMTS Overview26
PN3 PN4
PN5 PN6
PN1 PN1
Cell Site “1” transmits using PN code 1
PN2 PN2
Cell Site “2” transmits using PN code 2
Uplink: PN Code used to distinguish each Mobile Station
Downlink: PN Code used to distinguish each Base Station
Scrambling CodeScrambling Code

UMTS Overview27
Generation of Scrambling Codes
• Generated using Linear Feedback Shift Register Circuitry
• Codes in uplink uses 25 bit key to differentiate between different UEs
• Codes in downlink uses 18 bit key to differentiate between different Node Bs
• Both DL and UL code length is only first 38400 chip of the generated sequence
• Only 8192 Codes used in downlink speed up search process for Node B
• The 8192 codes are divided into
• 64 code group ( each has 8 primary codes) , so 512 Primary code
• Each primary code has 16 secondary codes

UMTS Overview28
Downlink Scrambling Codes
• Downlink Scrambling Codes
– Used to distinguish Base Station transmissions on Downlink
– Each Cell is assigned one and only one Primary Scrambling Code
– The Cell always uses the assigned Primary Scrambling Code for the Primary and
Secondary CCPCH’s
– Secondary Scrambling Codes may be used over part of a cell, or for other data channels
Primary SC0
Secondary
Scrambling
Codes
(16)
Secondary
Scrambling
Codes
(16)
Secondary
Scrambling
Codes
(16)
Secondary
Scrambling
Codes
(16)
Code Group #1 Code Group #64
8192 Downlink Scrambling Codes
Each code is 38,400 chips of a 218
- 1 (262,143 chip) Gold Sequence
3GPP TS 25.213 ¶ 5.2.2
3GPP TS 25.213 ¶ 5.2.2
Primary SC7 Primary SC504
Primary SC511
Scrambling CodeScrambling Code

UMTS Overview29
SSMA PN Code Planning
Spread Spectrum Code Planning Example
PN1
PN2
PN3PN7
PN6 PN4
PN5
PN1
PN2
PN3PN7
PN6 PN4
PN5 PN1
PN2
PN3PN7
PN6 PN4
PN5
PN1
PN2
PN3PN7
PN6 PN4
PN5
PN1
PN2
PN3PN7
PN6 PN4
PN5 PN1
PN2
PN3PN7
PN6 PN4
PN5
N
S
W E

UMTS Overview34
Orthogonal Codes
OC1, OC2
OC3, OC4
OC5, OC6, OC7
OC1 , OC2, OC3
OC1, OC2
OC1, OC2, OC3, OC4
Uplink: Orthogonal Codes used to distinguish data channels
coming from each Mobile Station
Downlink: Orthogonal Codes used to distinguish data channels
Coming from each Base Station

UMTS Overview35
Orthogonal Code Generation
• Generation of Orthogonal (Walsh) Codes
1
11 10
1111 1100 1010 1001
11111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110
Digital/Analog Mapping
logic 0 ↔ analog +1
logic 1 ↔ analog - 1
1100110011001100

UMTS Overview36
orthogonal Codes
• orthogonal Code Space: 5 users; one user has 4x
data bandwidth
User with 2x Bit Rate
= Unusable Code Space
480 kb/s 480 kb/s 480 kb/s 480 kb/s
1.92 Mb/s
Chip Rate = 3.840 Mcps
1
11 10
1111 1100 1010 1001
11111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110

UMTS Overview37
• Spreading Factor=Processing Gain= Rc/Rb
• Different spreading is done according to the service bit rate as the chip rate is constant.
37

UMTS Overview38
Code Locking Concept (PN Codes)
• PN codes is generated not stored
• Synchronization between Node B and
UE is extremely important to correctly
decode original information
• WCDMA mobiles use Code Locking
circuitry to lock on Scrambling code.
• TX, RX use same codes and same
time offset
– 100% correlation
• TX, RX use same codes, but
different time offset
– Low correlation “noise-like”
for any offset > +1 chip
• TX, RX use different codes
– Low correlation “noise-like”
at any time offset
• Average correlation level
proportional to
1/(code length)

UMTS Overview39
Code Locking Concept (Orthogonal Codes)
• TX, RX use same codes and same
time offset
– Orthogonal Codes 100% correlation
• TX, RX use same codes, but
different time offset
– Orthogonal Codes Unpredictable
results Orthogonality lost
• TX, RX use different codes
– Orthogonal Codes 0% Correlation

UMTS Overview40
Code Correlation
Input Data
+1 -1 +1
+1 -1 +1
Divide by
Code Length
Case I: Autocorrelation using a PN Code
Receiver and Transmitter use identical code at same time offset
+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1
PN code used
in Transmitter
x x x
+8 -8 +8
Integrate
Result
+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1
Transmitted
Sequence
= = =
+1 +1 +1 +1 +1 +1 +1 +1 -1 –1 –1 –1 –1 –1 –1 -1 +1 +1 +1 +1 +1 +1 +1 +1
= = =
+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1
PN Code
Used in Receiver
x x x
Transmitter
Receiver

UMTS Overview41
Code Correlation
Input Data
+1 -1 +1
+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1
+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1
-1 +1 –1 +1 +1 –1 -1 +1 +1 -1 +1 –1 +1 +1 –1 -1 -1 +1 +1 +1 –1 -1 +1 +1
-1 –1 –1 +1 –1 +1 –1 -1 -1 –1 –1 +1 +1 +1 +1 -1 -1 –1 +1 +1 +1 +1 +1 -1
PN code used
in Transmitter
Transmitted
Sequence
PN Code
Used in Receiver
-4 0 2
Integrate
Result
-0.5 0 0.25
Divide by
Code Length
Case II: Cross-Correlation using PN Codes
Receiver and Transmitter use different codes
x x x
= = =
x x x
= = =
Transmitter
Receiver

UMTS Overview42
Code Correlation
Transmitter
Input Data
+1 -1 +1
-1 +1 –1 +1 +1 –1 +1 -1 -1 +1 –1 +1 +1 –1 +1 -1 -1 +1 –1 +1 +1 –1 +1 -1
-1 +1 –1 +1 +1 –1 +1 -1 +1 –1 +1 –1 –1 +1 –1 +1 -1 +1 –1 +1 +1 –1 +1 -1
-1 +1 –1 +1 +1 –1 +1 -1 +1 +1 +1 +1 +1 +1 +1 +1 -1 -1 +1 –1 +1 +1 –1 +1
+1 +1 +1 +1 +1 +1 +1 +1 +1 –1 +1 –1 –1 +1 –1 +1 +1 –1 –1 –1 +1 –1 –1 -1
Orthogonal code
in Transmitter
Transmitted
Sequence
Orthogonal Code
used in Receiver
8 0 -4
Integrate
Result
+1 0 -0.5
Divide by
Code Length
Case III: Correlation using Orthogonal Codes
(a) Same Orthogonal code (b) Different Orthogonal codes (c) Same code with non-zero time offset
x x x
= = =
x x x
= = =
Receiver
1 Chip shift

UMTS Overview43
UMTS Overview
UMTS Network Architecture

UMTS Overview44
3G Radio Access Network - Highlights3G Radio Access Network - Highlights
Core Network
Voice Switched
Network
BTS
MSCBSC
GSM
handset
GSM Access Network
Packet
Switched
Network
SGSN
RNC
3G
handset NodeB
UMTSAccessNetwork

UMTS Overview45
GSM/GPRS Core Network (CN)
Iu Iu
RNS
RNC
RNS
RNC
Node B Node B Node B Node B
Iur
Iub
IubIub
Iub
User Equipment
(UE)
UTRAN
(UMTS
Terrestrial
Radio Access
Network)
PSTN
ISDN
Internet
Uu
3GPP TS 25.401 ¶ 6.0
3GPP TS 25.401 ¶ 6.0
MSC
GPRS
Service Node
Iu Iu
UMTS and UTRANUMTS and UTRAN

UMTS Overview46
UMTSUMTS Architecture..
•Two new node are integrated in the UTRAN network.
Node B (BTS equivalent)
Contains the RF equipment that provide the radio link in the air interface.
More intelligent than BTS.
Perform spreading/dispreading, channel coding, also responsible of a part
of the power control (inner loop).
RNC (radio network controller) (BSC equivalent).
Control several node Bs/ interface with the core network (MSC/SGSN).
Radio resources management.
Admission and congestion control.
Handover and power control (outer loop).
Ciphering/deciphering.
Can softly be divided into 3 types (CRNC, SRNC and DRNC)

UMTS Overview47
UMTS Overview
WCDMA Air Interface Principles

UMTS Overview48
Multi-path propagation Time dispersion
h(τ)
ττ0 τ1 τ2 τ3
τ0
τ1
τ2
τ3
The Radio ChannelThe Radio Channel

UMTS Overview49
• Fast (Rayleigh) Fading
time (mSec)
Composite
Received
Signal
Strength
Time between fades is related to
• RF frequency
• Geometry of multipath vectors
• Vehicle speed:
Up to 2 fades/sec per kilometer/hour
Deep fade caused by destructive summation
of two or more multipath reflections
msec
Multipath FadingMultipath Fading

UMTS Overview50
• CDMA Mobile Station RAKE Receiver Architecture
– Each finger tracks a single multipath reflection
–Also be used to track other base station’s signal during soft handover
– One finger used as a “Searcher” to identify other base stations
Finger #1
Finger #2
Finger #N
Searcher Finger
Combiner
Sum of
individual
multipath
components
Power measurement
of Neighboring
Base Stations
The RAKE ReceiverThe RAKE Receiver

UMTS Overview51
CDMA RAKE Receiver Architecture
BPF LPF
“I” PN
Code
(+1/-1)
“Q” PN
Code
(+1/-1)
Σ
Orthogon
al
Code
(+1/-1)
Integrate
over
‘SF’ chips
De-
Interleave
Data
Viterbi/
Turbo
Decoder
CRC
Verification
Decoded
Output
Bits
Error
Indication
cos(2fRFt)
Pilot
Orthogonal
Code
(all zeros)
Timing
Adj.
bit rate =
chip rate / SF
cos(2fIFt
)
Carrier
Frequency
Tracking
Loop
Other Rake Receiver Finger
Σ
Rake Receiver
“Finger”
D
D
I/Q
Demo
d
Correlator
The RAKE ReceiverThe RAKE Receiver Architecture

UMTS Overview52
BLER = Block Error Rate
SIR = Signal to Interference Ratio
TPC = Transmit Power Control
P(Startvalue)
Open loop
P(SIR-Target,UL)
P(SIR-Target, DL)
Inner loop
DL-TPC UL-TPC
SIR-Target,DL
BLER-Measured,DL
DL-Outer loop
RNC
SIR-Target,UL
SIR-Error,UL
UL-Outer loop
CDMA Power ControlCDMA Power Control

UMTS Overview53
• Inter-System Handover
–Handover from a CDMA system to an Analog or TDMA system
–Traffic and Control Channels are Disconnected and must be Reconnected
• Hard Handover
–When the MS must change CDMA carrier frequency during the Handover
–Traffic and Control Channels are Disconnected and must be Reconnected
• Soft Handover
–Unique to CDMA
–During Handover, the MS has concurrent traffic connections with two BS’s
–Handover should be less noticeable
• Softer Handover
–Similar to Soft Handover, but between two sectors of the same cell
–Handover is simplified since sectors have identical timing
HandoverHandover

UMTS Overview54
– One finger of the RAKE receiver is constantly scanning neighboring
Pilot Channels.
– When a neighboring Pilot Channel reaches the t_add threshold, the new
BS is added to the active set
– When the original Base Station reaches the t_drop threshold, originating
Base Station is dropped from the active set
Monitor Neighbor BS Pilots Add Destination BS Drop Originating BS
CDMA Soft HandoverCDMA Soft Handover

UMTS Overview55
Cell breathing conceptCell breathing concept
Cell breathing is a CDMA phenomena caused by the multiple access interference, and models the trade-
off between coverage and capacity
Max TX powerMax TX power
Interfering
Signals
Desired Signal

UMTS Overview56
Cell breathing conceptCell breathing concept
Cell breathing is a CDMA phenomena caused by the multiple access interference, and models the trade-
off between coverage and capacity
Interfering
Signals
Desired Signal
Noise rise (interference margin)Noise rise (interference margin) αα number of usersnumber of users

UMTS Overview57
F - factor :
 The ratio between the interference from other cells and the interference generated in the own
cell
 A typical value of 0.65 in a system consisting of three sectors derived by simulations
own
other
I
I
f =
Factors influence WCDMA capacityFactors influence WCDMA capacity

UMTS Overview58
Quadrature Spreading and Modulation
• WCDMA system uses QPSK Modulation Scheme
• Separates input stream into two channels I and Q
• I and Q spread and de-spread separately using scrambling codes
• Modulation to desired RF frequency uses sine for Q and cosine for I
• Modulation symbol on air consists of 2 Consecutive bits / chips
• Modification on QPSK used in real transmitters to enhance power utilization

UMTS Overview59
Quadrature Spreading and Modulation
• Constellation diagram of the standard QPSK Modulation
I
Q
( I = 1, Q = 1 )
( I = -1, Q = -1 )
( I = -1, Q = 1 )
( I = 1, Q = -1 )
1 Modulation Symbol represents 2 data bits
Modulation efficiency = 2 bits/symbol
RF Carrier amplitude
RF Carrier phase angle
Cos ωt
Sin ωt

UMTS Overview60
Quadrature Spreading and Modulation TX

UMTS Overview61
Quadrature Spreading and Modulation RX
• By multiplying by the sin and cosine at the receiver, the
original I and Q data streams are recovered
90o
SUM
cos ( 2  fRF t)
I sin ( 2  fRF t)
+ Q cos ( 2  fRF t)
LPF
LPF
Data Stream #1 “ I ”
Data Stream #2 “ Q ”
+1
-1
+1
-1

UMTS Overview62
Voice Coding
• Example: Two ways to hear the sax player
Record the sax player onto a CD... ... and play back the CD
20 MB per song
Write down the notes he plays... ... and have a friend play the same notes
20 kB per song

UMTS Overview63
Voice Coding
• Vocoding
Human Voice:
‘ss’, ‘ff’, ‘sh’ … ~20% of time
‘ah’, ‘v’, ‘mm’ , … ~80% of time
Transmitted Parameters
8~12 kb/s typical,
vs.
64 kbps for log-PCM
32 kbps for ADPCM
Vocoder
White Noise Generator
Pulse Generator
Σ
Voice Re-Synthesis at the Receiver
Noise
parameters
Pitch
parameters
H(s)
Filter poles
correspond to
resonances of the
vocal tract
Speech
Output
H(s)
Voice Coding in WCDMA

UMTS Overview64
ACELP/AMR Voice Coding
A/D
Linear
Predictive
Coding
(LPC)
Filter
Codebook
Index
Codebook
Perceptual
Weighting
Error
Analysis
Speech
Generator
Vocoder
Output Bits
MUX
Voice, Tone
Activity
Detectors
• Mode Indication bits
• Comfort Noise
• Tone Emulation
(+)
(-)
Prediction
Error
ACELP (Algebraic code excited linear predictive)/AMR Voice Coding
WCDMA AMR data rate:
12.2,7.95,5.9 and 4.75Kb/s

UMTS Overview65
Digital Cellular Error Correction
• Example: Mailing a letter in the US
– Extra (redundant) symbols in address help correct lost symbols
– ZIP codes used to detect errors in the address
John Doe
123 East 45th Street
New York City, New York 10017
JD
123 E 45
NYC NY
With minimal data...
Errors are uncorrectable
With redundant data...
Errors are correctable
Bandwidth utilization: 13 bytes Bandwidth utilization: 48 bytes

UMTS Overview66
CRC Coding
• Cyclic-Redundancy Check (CRC) Coding
– Identifies corrupted data
– If there is an error, the receiver can request that data be re-sent
– For voice data errors, the vocoder discards any bad data
Checksum
011010
Original Data
100101101010
CRC
Generator
Original Data
100101101010
CRC
Generator
Re-Generated Checksum
011011
Transmitter
Receiver
If Checksums do not match,
there is an error
Received Data
100101001010
Received Checksum
011010
RF
Transmission Path

UMTS Overview67
CRC Coding
• Cyclic-Redundancy Check (CRC) Coding: Example
– 22-bit in /6-bit out CRC: g(x) = [ x6
+ x2
+ x + 1 ]
Input Data b1b2b3b4b5 … b22
D
CRC (6 bits)
c1c2c3c4c5c6
D D D D D
0
0
Input Data (22 bits)
b1b2b3b4b5 … b22
Output
Output
clock
D Shift Register (one unit delay)
All switches “up” for first 22 bits;
All switches “down” for last 6 CRC bits

UMTS Overview68
The Convolutional Coder
• Convolutional Coding
Original Data
00011011...
FEC
Generator
FEC Encoded data
1010011100110110...
Original Data
00011011
Viterbi
Decoder
Transmitter
Receiver
RF
Transmission Path

UMTS Overview69
Convolution Coder
• Convolutional Coding: Example
D DInput Data 1010...
MUX
X2k+1
X2k
Coder Output
clock
R = 1/2 , k=2 Convolutional Coder
• For every input bit, there are two output bits
• The maximum time delay is 2 clock cycles

UMTS Overview70
Turbo Coding
• Turbo Codes
– Outperform Convolutional codes
–Requires much more processing power; data packets may be decoded off-line
–Used for high-bit rate data and packet data
– Interleaving (time diversity) enhances error correction
Encoder #1
Encoder #2
MUX
Data
Decoded
Data
DE-
MUX
Decoder #2
D
P1
P2
D
P1
P2
D
Turbo Encoder Turbo Decoder
Interleaver
Interleaver
Interleaver
De-Interleaver
Decoder #1

UMTS Overview71
Interleaving 1st
level
Time
Amplitude
To Viterbi
decoder
Original Data Samples
1 2 3 4 5 6 7 8 9
Interleaving
Matrix
1 2 3
4 5 6
7 8 9
Transmitter
Interleaved Data Samples
1 4 7 2 5 8 3 6 9
RF
Transmission Path
Interleaved Data Samples
1 4 7 2 5 8 3 6 9
Errors Clustered
De-
Interleaving
Matrix
1 2 3
4 5 6
7 8 9
De-Interleaved Data Samples
1 2 3 4 5 6 7 8 9
Receiver
Errors Distributed
2 stages of interleaving in WCDMA:
•1st
stage: data interleaving
•2nd
stage block interleaving

UMTS Overview72
Interleaving
• Interleaving (‘K’ blocks containing (R x C) bits each)
0, 1, 2, 3, - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - , (RC - 1)
0
C
•
•
(R-1)C
1
C+1
•
•
(R-1)(C+1)
- - -
- - -
m
C+m
•
•
(R-1)(C+m)
C-1
2C-1
•
•
RC-1
- - -
- - -
0
C
•
•
(R-1)C
m
C+m
•
•
(R-1)(C+m)
1
C+1
•
•
(R-1)(C+1)
C-1
2C-1
•
•
RC-1
C0 Cm C1 CF-1
Before
Interleaving
Write Data
into Matrix
Row-wise
After
Interleaving 0, C, … , (R-1)C , m, C+m, … (R-1)(C+m) , … , 1, C+1 , (R-1)(C+1), .., C-1 , 2C-1 , … RC-1
Read Data
from Matrix
Column-wise
C0 C1 Cm CC-1- - - - - -
Permute
Matrix
Columns
Interleaving 2nd
level

UMTS Overview73
WCDMA Standards
• Both FDD (2x 5 MHz) and TDD (1x 5 MHz) modes are supported
• BTSs time synchronization not required for FDD mode
• GPS not required
• Multi-Code and Variable Spreading Factor modes supported
• Physical Parameters:
– Chip rate = 3.840 Mchips/Sec
– RF Bandwidth = 5 MHz
– Frame length = 10 mSec, so 100 Frame/ Sec
– Frame consists of 15 Slot each 0.666 msec , so 1500 Slot./Sec
– Fast Power Control: Bi-directional; 1500 updates/sec or once /Slot
2025 2110
FDD UPLINK TDD FDD DOWNLINK
1920 1980 2010 2170
WCDMA /
EUROPE
1850 1910
FDD UPLINK
1930 1990
WCDMA /
USA FDD DOWNLINKTDD
TDD
1900

UMTS Overview74
UMTS Model
• UMTS OSI Model
Radio Resource Control
(RRC)
Medium Access Control (MAC)
Transport channels
- grouped by method of transport
Physical layer
Layer 3
Logical channels
- grouped by information
content
- User Data
- Control and signaling
Layer 2
Layer 1
Physical channels
Physical Channels Distinguished by:
- RF Frequency
- Channelization Code
- Spreading Code
- Modulation (I/Q) Phase (uplink)
- Timeslot (TDD mode)
Air Interface
3GPP TS 25.201 ¶ 4.0
3GPP TS 25.201 ¶ 4.0
Direct RRC control
of the physical layer

UMTS Overview77
Physical Layer Requirements
• Services provided by Physical Layer
• Data and RF Processing Functions
• FEC encoding/decoding of transport channels
• Error detection on transport channels and indication to higher layers
• Rate matching of coded transport channels to physical channels
• Power weighting and combining of physical channels
• Closed-loop power control
• Modulation/demodulation and spreading/de-spreading of physical channels
• Multiplexing/de-multiplexing of coded composite transport channels
• Mapping of transport channels on physical channels
• Operational Functions
• Cell search functions
• Synchronization (chip, bit, slot, and frame synchronization)
• Soft Handover support
• Radio characteristics measurements including FER, SIR, Interference Power, etc.,
and indication to higher layers

UMTS Overview78
WCDMA Physical Channels
Base
Station
(BS)
User
Equipment
(UE)
P-CCPCH- Primary Common Control Physical Channel
SCH - Sync Channel
P-CPICH - Primary Common Pilot Channel
S-CCPCH Common Control Physical Channel (Secondary)
Channels broadcast to all UE in the cell
DPDCH - Dedicated Physical Data Channel
DPCCH - Dedicated Physical Control Channel
Dedicated Connection Channels
PICH - Page Indication Channel
Common control Channels
PRACH - Physical Random Access Channel
AICH - Acquisition Indication Channel
Random Access and Packet Access Channels

UMTS Overview79
WCDMA Downlink Physical Channels
• Common Downlink Physical ChannelsCommon Downlink Physical Channels
–P-CCPCH Common Control Physical Channel (Primary)
- Broadcasts cell site information
- Broadcasts cell SFN; Timing reference for all DL channels
–SCH Synchronization Channel
- Fast Synch. codes 1 and 2; time-multiplexed with P-CCPCH
–S-CCPCH Common Control Physical Channel (Secondary)
- Transmits idle-mode signaling and control information to UE’s
–P-CIPCH Common Pilot Channel
• Dedicated Downlink Physical ChannelsDedicated Downlink Physical Channels
–DPDCH Dedicated Downlink Physical Data Channel
–DPCCH Dedicated Downlink Physical Control Channel
- Transmits connection-mode signaling and control to UE’s

UMTS Overview80
WCDMA Downlink Physical Channels
• Downlink Indication ChannelsDownlink Indication Channels
– AICH (Acquisition Indication Channel)
–Acknowledges that BS has acquired a UE Random Access attempt
–(Echoes the UE’s Random Access signature)
– PICH (Page Indication Channel)
–Informs a UE to monitor the next paging frame

UMTS Overview81
WCDMA Uplink Physical Channels
–Common Uplink Physical ChannelsCommon Uplink Physical Channels
–PRACH Physical Random Access Channel
Used by UE to initiate access to BS
–Dedicated Uplink Physical ChannelsDedicated Uplink Physical Channels
–DPDCH Dedicated Uplink Physical Data Channel
–DPCCH Dedicated Uplink Physical Control Channel
Transmits connection-mode signaling and control to BS
Uplink Physical Channels

UMTS Overview82
• Downlink DPCCH/DPDCH Frame
Data 2TFCIData 1 TPC
1 Slot = 0.666 mSec = 2560 chips = 10 x 2^k bits, k = [0...7]
SF = 512/2k
= [512, 256, 128, 64, 32, 16, 8, 4]
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1 Frame = 15 slots = 10 mSec
DPDCH
Pilot
DPDCH DPCCH DPCCH
Dedicated Control/Data Channel

UMTS Overview83
• Variable Data Rates on the Downlink: Examples
Bits/Frame Bits/ Slot
DPCCH
Channel Bit
Rate
(kbps)
Channel
Symbol
Rate
(ksps)
SF
TOTAL DPDCH DPCCH TOTAL DPDCH
TFCI TPC PILOT
15 7.5 512 150 60 90 10 4 0 2 4
120 60 64 1200 900 300 80 60 8 4 8
1920 960 4 19,200 18,720 480 1280 1248 8 8 16
Coded Data
1.920 Mb/sec
(19,200 bits
per 10 mSec frame)
S/P
Converter
Channel Coding
(OVSF codes at 3.84 Mcps)
960 kb/sec
Downlink Data Rates

UMTS Overview84
14 480 240 16 320 56 232 8 8* 16 15
14A 480 240 16 320 56 224 8 16* 16 8-14
14B 960 480 8 640 112 464 16 16* 32 8-14
15 960 480 8 640 120 488 8 8* 16 15
15A 960 480 8 640 120 480 8 16* 16 8-14
15B 1920 960 4 1280 240 976 16 16* 32 8-14
16 1920 960 4 1280 248 1000 8 8* 16 15
16A 1920 960 4 1280 248 992 8 16* 16 8-14
DPDCH
Bits/Slot
DPCCH
Bits/Slot
Slot
Format
#i
Channel
Bit Rate
(kbps)
Channel
Symbol
Rate
(ksps)
SF Bits/
Slot
NData1 NData2 NTPC NTFCI NPilot
Transmitted
slots per
radio frame
NTr
0 15 7.5 512 10 0 4 2 0 4 15
0A 15 7.5 512 10 0 4 2 0 4 8-14
0B 30 15 256 20 0 8 4 0 8 8-14
1 15 7.5 512 10 0 2 2 2 4 15
1B 30 15 256 20 0 4 4 4 8 8-14
2 30 15 256 20 2 14 2 0 2 15
2A 30 15 256 20 2 14 2 0 2 8-14
2B 60 30 128 40 4 28 4 0 4 8-14
3 30 15 256 20 2 12 2 2 2 15
3A 30 15 256 20 2 10 2 4 2 8-14
3B 60 30 128 40 4 24 4 4 4 8-14
Notes:
1) Zero-TFCI slot formats
are used when there is
only one data service on
the DCH.
2) Slot formats A and B are
used during
compressed mode
operation
Downlink DPDCH/DPCCH Slot Formats

UMTS Overview85
• Downlink Scrambling Codes
– Used to distinguish Base Station transmissions on Downlink
– Each Cell is assigned one and only one Primary Scrambling Code
– The Cell always uses the assigned Primary Scrambling Code for the Primary and
Secondary CCPCH’s
– Secondary Scrambling Codes may be used over part of a cell, or for other data channels
Primary SC0
Secondary
Scrambling
Codes
(15)
Secondary
Scrambling
Codes
(15)
Secondary
Scrambling
Codes
(15)
Secondary
Scrambling
Codes
(15)
Code Group #1 Code Group #64
8192 Downlink Scrambling Codes
Each code is 38,400 chips of a 218
- 1 (262,143 chip) Gold Sequence
Primary SC7 Primary SC504
Primary SC511

UMTS Overview86
• Synchronization Codes (PSC, SSC)
• Broadcast by BS
–First 256 chips of every SCH time slot
– Allows UE to achieve fast synchronization in an asynchronous
system
– Primary Synchronization Code (PSC)
–Fixed 256-chip sequence with base period of 16 chips
–Provides fast positive indication of a WCDMA system
–Allows fast asynchronous slot synchronization
– Secondary Synchronization Codes (SSC)
–A set of 16 codes, each 256 bits long
–Codes are arranged into one of 64 unique permutations
–Specific arrangement of SSC codes provide UE with frame timing, BS
“code group”
P-CCPCH
(PSC + SSC + BCH)2304 Chips256 Chips
Broadcast Data (18 bits)
SSCi
PSC
Synchronization Codes

UMTS Overview87
Primary Synchronization Code
• Primary Synchronization Code (PSC)
let a = <1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1>
PSC(1...256) = < a, a, a, -a, -a, a, -a, -a, a, a, a, -a, a, -a, a, a >
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Note: PSC is transmitted “Clear” (Without scrambling)
Broadcast Data (18 bits)
SSCi
2304 Chips256 Chips
SCH BCH
PSC

UMTS Overview88
• 16 Fixed 256-bit Codes; Codes arranged into one of 64 patterns
slot numberScrambling
Code Group
#1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15
Group 1 1 1 2 8 9 10 15 8 10 16 2 7 15 7 16
Group 2 1 1 5 16 7 3 14 16 3 10 5 12 14 12 10
Group 3 1 2 1 15 5 5 12 16 6 11 2 16 11 15 12
• • •
• • •
• • •
Group 62 9 10 13 10 11 15 15 9 16 12 14 13 16 14 11
Group 63 9 11 12 15 12 9 13 13 11 14 10 16 15 14 16
Group 64 9 12 10 15 13 14 9 14 15 11 11 13 12 16 10
Note:
The SSC patterns positively identify one and only one of the 64 Scrambling Code Groups.
This is possible because no cyclic shift of any SSC is equivalent to any cyclic shift of any other SSC.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
SSC1
SSC2
SSC3
SSC4
SSC5
SSC6
SSC7
SSC8
SSC9
SSC10
SSC11
SSC12
SSC13
SSC14
SSC15
SSC16
SSCi
SSC1 SSC15
Secondary Synchronization Code Group

UMTS Overview89
• Slot Synchronization using Primary Synchronization
Code
BCH
Data
PSC
[1]
BCH
Data
PSC
[2]
BCH
Data
PSC
[3]
BCH
Data
PSC
[4]
BCH
Data
PSC
[15]
Matched Filter
(Matched to PSC)
10 mSec Frame (15 slots x 666.666 uSec)
Matched
Filter
Output
time
P-CCPCH
(PSC)
Slot Synchronization

UMTS Overview90
• Frame Synchronization using Secondary
Synchronization Code
BCH
Data
SSC
[1]
BCH
Data
SSC
[2]
BCH
Data
SSC
[3]
BCH
Data
SSC
[4]
BCH
Data
SSC
[15]
Matched Filter
Matched to SSC
code group pattern
10 mSec Frame (15 slots x 666.666 uSec)
Matched
Filter
Output
time
SSC
[2]
SSC
[3]
SSC
[4]
SSC
[1]
SSC
[6]
SSC
[7]
SSC
[8]
SSC
[5]
SSC
[10]
SSC
[11]
SSC
[12]
SSC
[9]
SSC
[14]
SSC
[15]
SSC
[13]
SSC Code Group Pattern provides
• Frame Synchronization
• Positive ID of Scrambling Code Group
Remember, no cyclic shift of any SSC is equal to any other SSC
Frame Synchronization

UMTS Overview91
• Random Access Attempt and AICH Indication
Pre-
amble
Pre-
amble
Pre-
amble
AICH
RACH
No
Ind.
No
Ind.
Acq.
Ind.
RACH
message part
(UE Identification)UE
BS
4096 chips
(1.066 msec)
Random Access

UMTS Overview92
Random Access Preamble Signature Symbols
Signature P0 P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 P13 P14 P15
0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1
2 1 1 -1 -1 1 1 -1 -1 1 1 -1 -1 1 1 -1 -1
3 1 -1 -1 1 1 -1 -1 1 1 -1 -1 1 1 -1 -1 1
4 1 1 1 1 -1 -1 -1 -1 1 1 1 1 -1 -1 -1 -1
5 1 -1 1 -1 -1 1 -1 1 1 -1 1 -1 -1 1 -1 1
6 1 1 -1 -1 -1 -1 1 1 1 1 -1 -1 -1 -1 1 1
7 1 -1 -1 1 -1 1 1 -1 1 -1 -1 1 -1 1 1 -1
8 1 1 1 1 1 1 1 1 -1 -1 -1 -1 -1 -1 -1 -1
9 1 -1 1 -1 1 -1 1 -1 -1 1 -1 1 -1 1 -1 1
10 1 1 -1 -1 1 1 -1 -1 -1 -1 1 1 -1 -1 1 1
11 1 -1 -1 1 1 -1 -1 1 -1 1 1 -1 -1 1 1 -1
12 1 1 1 1 -1 -1 -1 -1 -1 -1 -1 -1 1 1 1 1
13 1 -1 1 -1 -1 1 -1 1 -1 1 -1 1 1 -1 1 -1
14 1 1 -1 -1 -1 -1 1 1 -1 -1 1 1 1 1 -1 -1
15 1 -1 -1 1 -1 1 1 -1 -1 1 1 -1 1 -1 -1 1
• Preamble codes are 16-long Orthogonal Walsh Codes.
• Preamble = [ P0, P1, … P15 ] repeated 256 times (4096 chips total).
• Preamble codes help the BS distinguish between UE making simultaneous Random Access Attempts.
Random Access Preamble Signatures

UMTS Overview93
BCCH
Broadcast Control Ch.
PCCH
Paging Control Ch.
CCCH
Common Control Ch.
DCCH
Dedicated Control Ch.
DTCH
Dedicated Traffic Ch. N
BCH
Broadcast Ch.
PCH
Paging Ch.
FACH
Forward Access Ch.
DCH
Dedicated Ch.
P-CCPCH(*)
Primary Common Control Physical Ch.
S-CCPCH
Secondary Common Control Physical Ch.
DPDCH (one or more per UE)
Dedicated Physical Data Ch.
DPCCH (one per UE)
Dedicated Physical Control Ch.
Pilot, TPC, TFCI bits
SSCi
Logical Channels
(Layers 3+)
Transport Channels
(Layer 2)
Physical Channels
(Layer 1)
Downlink
RF Out
DPCH (Dedicated Physical Channel)
One per UE
DSCH
Downlink Shared Ch.
SHCCH
DSCH Control Ch.
CTCH
Common Traffic Ch.
CPICH
Common Pilot Channel
Null Data
Data
Encoding
Data
Encoding
Data
Encoding
Data
Encoding
Data
Encoding
PDSCH
Physical Downlink Shared Channel
AICH
(Acquisition Indication Channel)
PICH
(Paging Indication Channel )
Access Indication data
Paging Indication bits
AP-AICH
(Access Preamble Indication Channel )
Access Preamble Indication bits
CSICH
(CPCH Status Indication Channel )
CPCH Status Indication bits
CD/CA-ICH
(Collision Detection/Channel Assignment )
CPCH Status Indication bits
WCDMA Downlink (FDD)
S/P
S/P
Cch
S/P
S/P
S/P
S/P
S/P
S/P
S/P
S/P
Cell-specific
Scrambling
Code
I+jQ I/Q
Modulator
Q
I
Cch
Cch
Cch
Cch
Cch
Cch
Cch
Cch 256,1
Cch 256,0
Σ
GS
PSC
GP Σ
Sync Codes(*)
* Note regarding P-CCPCH and SCH
Sync Codes are transmitted only in bits 0-255 of each timeslot;
P-CCPCH transmits only during the remaining bits of each timesl
Σ Filter
Filter
Gain
Gain
Gain
Gain
Gain
Gain
Gain
Gain
Gain
Gain
SCH (Sync Channel)
DTCH
Dedicated Traffic Ch. 1
DCH
Dedicated Ch.
Data
Encoding
M
U
X
M
U
X
CCTrCH
DCH
Dedicated Ch.
Data
Encoding

UMTS Overview94
Logical Channels
(Layers 3+)
Transport Channels
(Layer 2)
Physical Channels
(Layer 1)
Uplink
RF Out
WCDMA Uplink (FDD)
UE
Scrambling
Code
I+jQ I/Q
Mod.
Q
I
Chc
Σ
ΣI
Filter
Filter
CCCH
Common Control Ch.
DTCH (packet mode)
Dedicated Traffic Ch.
RACH
Random Access Ch.
PRACH
Physical Random Access Ch.
DPDCH #1
CPCH
Common Packet Ch.
PCPCH
Physical Common Packet Ch.
Data
Coding
Data
Coding
DPDCH #3 (optional)
DPDCH #5 (optional)
DPDCH #2 (optional)
DPDCH #4 (optional)
DPDCH #6 (optional)
ΣQ
DPCCH
Dedicated Physical Control Ch.
Pilot, TPC, TFCI bits
Chd
Gc
Gd
j
Chd,1 Gd
Chd,3 Gd
Chd,5 Gd
Chd,2 Gd
Chd,4 Gd
Chd,6 Gd
Chc Gd
Chc
Σ
Chd
Gc
Gd
j
RACH Control Part
PCPCH Control Part
Σ
j
Σ
DCCH
Dedicated Control Ch.
DTCH
Dedicated Traffic Ch. N
DCH
Dedicated Ch.
Data
Encoding
DTCH
Dedicated Traffic Ch. 1
DCH
Dedicated Ch.
Data
Encoding M
U
X
CCTrCH
DCH
Dedicated Ch.
Data
Encoding

UMTS Overview95
UMTS Overview
Coverage and capacity principles

UMTS Overview96
WCDMA planning complexity
Coverage/capacity/quality Trade-off
Quality
Coverage Capacity
WCDMA
BLER
BER
GoS
Cell Breathing
•Unlike GSM (TDMA), both coverage and capacity are related together and to be
dimensioned by the same factor, (Power), which reflect of a trade of between
coverage and capacity (cell breathing)

UMTS Overview97
Dimensioning flow in 3G

UMTS Overview98
Capacity Dimensioning
• CS dimensioningCS dimensioning
–Same as GSM (Earlng B table).
-Get number of resources Mcs
• PS dimensioningPS dimensioning
–Peak hour total data needed.
–Get figure in bit/sec.
Throughput for
each user
average
64kb/s

UMTS Overview99
– Available capacity calcualtions (capacity per one site)Available capacity calcualtions (capacity per one site)
–For each service determine.
– Eb/No  depending on the channel coding type and power control efficiency
– Ec/No  depending on the PG
–Calculate MpoleCalculate Mpole
–Uplink.
–Downlink

UMTS Overview100
– Define Max load QmaxDefine Max load Qmax
–For each cell parameter Q is defined representing the ratio of the carreied
traffic (Mdata) to the max carreid traffic (Mpole)
–Qmax for the downlink is to be 75%
–Qmax for the uplink is to be 70%
–Calculate number for capacity sitesCalculate number for capacity sites
–Qmax=(Mdata/ Mpole)* number of sites
–The number of sites is to be calculated for each service, for both the
downlink and the uplink.
–Limitation for each service is the max number of sites either in the
downlink and the uplink

UMTS Overview101
130
135
140
145
150
155
160
165
0 10 20 30 40 50 60 70 80
Number of Users
PropagationlossdB
WCDMA capacity calculation
UL and DL load curves comparison:
DL
UL
At low load, system
is UL limited
At high load, system
is DL limited

UMTS Overview102
WCDMA Coverage dimensioing
Max Path LossMax Path Loss
Using link budget
equation
RXimumTXMaximum ySensitivitPowerL −= max
∑ ∑+−= GainsinsMLL MaximumPath arg

UMTS Overview103
-Uplink link budget equation,-Uplink link budget equation,
–Determine SSreq
– Ec=No + Eb/No + PG.
–Apply link budget equation to get Rmax.
–Balanced?
Coverage dimensioning

UMTS Overview104
• Downlink link budget equation,Downlink link budget equation,
–Apply link budget equation to get Pdl (Cpich power.).
–Check the balance through the following checks.
–Balanced

UMTS Overview105
• Downlink link budget equation,Downlink link budget equation,
–Calculate the total power (DCH)
–Through Simulation!

UMTS Overview106
UMTS Overview
Introduction to HSDPA

UMTS Overview107
HSDPA main principle
• What is HSDPA?
High-Speed Downlink Packet Access (HSDPA) is a new feature at WRAN to provide high data
rates at the downlink to meet users needs.
• How HSDPA works?
In order to increase the data rate:
• The modulation technique has been changed from QPSK to 16 QAM.
• A new transport channel has been introduced to the system at the same carrier for packed
data “HS-DSCH”, this channel utilize the remaining amount of power at the power amplifier &
share it quickly among the users.
• The main benefits of HS-DSCH is
– Reduced delays
– Increased data rates
– Increased capacity
• The TX power at HS-DSCH is changed dynamically “very fast” every 2ms to adapt with RL
changes, ie similar to power control but very as we use the remaining power at PA which may
needed again for urgency conditions.
• Using more than one channelization code for the user, this code used at SF16 at code tree.

UMTS Overview108
througput
• Available throughputs
HSDPA main principle
Number of HS-
PDSCH
codes
5 5 10 10 15 15
Modulation QPSK 16QAM QPSK 16QAM QPSK 16QAM
Maximum bit
rate [Mbps]
2.24 4.48 4.48 8.96 6.72 13.44

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