umts system survey
DESCRIPTION
3G System SurvayTRANSCRIPT
UMTS System Survey
Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines
1. Before We Start
2. UMTS Introduction
4. UMTS Network Architecture.
3. WCDMA Concepts.
5. UMTS Air Interface Principles.
6. UMTS Procedures
7. UMTS services and applications
Before We Start Before We Start 11
Delegates for this course should be aware of the following topics:‐
Detention of Communication System.
Type of Communication according to medium typeType of Communication according to medium type.
Wire Communication.
Wireless Communication.
Type of Communication according to medium accessibility.
Simplex communication.
Half & Full duplex communication.
Concept of the modulation in the communication system, as well as different types of analog and digital modulation.
AM ASK.
FM FSK.
PM PSK
Before We Start Before We Start 22
Delegates for this course should be aware of the following topics:‐
Digital Vs Analog communication.
Digital communication principlesDigital communication principles.
Sampling.
Quantization.
Source coding and channel coding.
Modulation and Shannon theory.
Different Multiple access techniques.
TDMA
FDMAFDMA
CDMA
Circuit switching and Packet switching concept.
Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines
1. Before We Start
2. UMTS Introduction
4. UMTS Network Architecture.
3. WCDMA Concepts.
5. UMTS Air Interface Principles.
6. UMTS Procedures
7. UMTS services and applications
00G: MTS Mobile telephone SystemG: MTS Mobile telephone System
System DescriptionSystem DescriptionIntroduced in the late 40’s, by AT&T.
High power transmitter at high elevationHigh power transmitter, at high elevation.
First time to introduce the mobility.
Analog System FM; 120KHz BW enhanced to 30KHz….Max 12CH
No coverage continuity.
Initially half duplex system; upgraded to a full duplex one in 1950.
Very limited capacity and low quality
CallWashington Baltimoredropped
g
11G:AMPS Advanced Mobile Phone ServiceG:AMPS Advanced Mobile Phone Service
System DescriptionSystem DescriptionThe first introduction of the cellular concept.
F t Wh f h thFreq reuse concept When you are far‐enough away you can re‐use the channel
Many Cells with low power; instead of few cells with high power.
Analog based system (FM).
Low quality.
Introducing the Handover concept.
Ch #1 Ch #2 Ch #3 Ch #1
Reuse DistanceReuse Distance
First generation different standardFirst generation different standard
22G:GSM global system of mobile communicationG:GSM global system of mobile communication
System DescriptionSystem DescriptionA complete digital system (FDMA / TDAM).FSK modulation (GMSK).Better quality (coding) and quality (encryption) than 1G.124 Ch at 900MHz.45MHz duplex distance45MHz duplex distance.Voice service only.Better Utilization TDMA vs. analog.
GSM SpectrumGSM Spectrum
GSM900 890‐915 / 935‐960 MHz
E‐GSM 880‐915 / 925‐960 MHz
GSM1800 1710‐1785 / 1805‐1880
GSM1900 1850 1910 / 1930 1990 MHzGSM1900 1850‐1910 / 1930‐1990 MHz
GSM‐R 876‐880 / 921‐925 MHz
GSM450 450.4‐457.6 / 460.4‐467.6 MHz
GSM480 478.8‐486 / 488.8‐496 MHz
GSM850 824‐849 / 869‐894 MHz
PDC
Second generation different standardSecond generation different standard
GSM:Global System for
PDC:Personal Digital Cellular
since 1993/94J lMobile Communication
since 1992world‐wide:
≈ 165 countries
Japan only800 & 1500 MHz
≈ 70 M. subscriber
900, 1800 & 1900 MHz
subscriber: ≈ 550 M.
IS‐95:Interim Standard‐95
since 1995
D‐AMPS:Digital AMPS
welt‐wide, America & S. Korea
800 & 1900 MHz, 1700 MHz (Korea)
since 1991/92USA, Canada800 & 1900 MHzAMPS/D‐AMPS ( )
≈ 100 M. subscribersubscriber: ≈ 90 M.
22G system Evolution.G system Evolution.
22
22G system Evolution.G system Evolution.
22G system Evolution.G system Evolution.
GPRS (GPRS (22..5 5 G)G)Stands For General Packet Radio System.Introduced in the late 90’s.System is capable of packet switching in addition to circuit switchingSystem is capable of packet switching in addition to circuit switching.GSM structured network; (Core network impacted).Data rate up to 20Kb/s per time slot and maximum of 160Kb/s.Pure PS rather than HSCSD.
EDGE (EDGE (22..75 75 G)G)Stands Enhanced data GPRS evolution.
d dIntroduced in 2001.GSM/GPRS structure network.Enhancing data rate up to 59Kb/s per time slot and 473Kb/s.8 PSK modulation instead of GMSK.
2Radio network impact.
2
UMTS UMTS 33G DriversG Drivers
Consumer demand for widebandConsumer demand for widebandservices
Imaging
Wireless postcardMobile transactions
Increased network capacity
More airtime Access anytime, anyplaceMore Subscribers
Mobile TrendMobile Trend
100 VoiceData
60
80
[%]
Data
40
60
Traf
fic [
20
T
Trend: Voice ⇒ Data
01996 2001 2005 2007
YYear
Mobile TrendMobile Trend
UMTS DriverUMTS Driver
Video conferences
video telephony
Tele‐Shopping
Electronic newspapersImages / Sound files
Tele‐BankingFinancial services
Images / Sound filesUMTS offers
flexible & dynamicdata rates:
8 kbit/ 2 Mbit/Data base access
Information services
E il
8 kbit/s ‐ 2 Mbit/s
E‐mail
Voice
10 100 1000 10.000Data rate [kbit/s]
33G ServicesG Services
VOICE Improved Voice Quality
CAPACITY Voice & Data Usage
Mobile TV Streaming TV session with data rate 128Kb/s
SPEED Higher bit rates: up to 384 kbps
Mobile TV
Video telephone Video Telephony with data rate starting from 64kb/s
Mobile Navigation Precise Location based Services
UMTS developmentUMTS development
ETSI(Europe) TIA, T1
(USA)
ARIB, TTC(Japan)
( )
CATT( )
TTA(South Korea)
(China)
ESA Iridium(South Korea)
ICO, Inmarsat
ESA, Iridium(MSS)
(MSS)
UMTS developmentUMTS development
UMTS development UMTS development 33GPP foundationGPP foundation
ETSIEuropean Telecommunication
Standards Institute ARIB/TTCAssociation of Radio IndustriesTTA
3GPP
& Business / TelecommunicationTechnology Committee, Japan
GSAGlobal Mobile Supplier
Association
TSACCTelecommunication
Standards Advisory Council
Telecommunications TechnologyAssociation, South Korea
IPv63GPP3rd Generation
Partnership Project
UMTSForum
TIATelecommunicationIndustry Association,
USA
of Canada
UWCCUniversal WirelessC i ti
IPv6Forum
ACIF
CWTSChina Wireless
Telecommunications GSM
CommunicationsConsortiumWMF
Wireless MultimediaForum
MWIFMobile WirelessInternet Forum3G.IP
Forum
ACIFAustralian Communications
Industry Forum
Standards Association
MPR: Market Representation Partner
Organisational Partner
Observership status
ANSI T1Committee T1
Telecommunications
UMTS developmentUMTS development
IMTIMT--2000 2000 road maproad map
UMTS standardization UMTS standardization
• Standardization organizations such as 3GPP, 3GPP2 were established3GPP2 were established
WCDMA CDMA2000
3G system
WCDMA
3GPP
FDD/TDD mode
CDMA2000
3GPP2
Spectrum AllocationSpectrum Allocation
33G system Evolution.G system Evolution.
UMTS RUMTS R99 99 ((33G)G)Stands for Universal mobile telecommunication systemIntroducing the WCDMA technique for mobile communication.60MH t ll ti t 2G60MHz spectrum allocation at 2G.12 CHs at 5MHz BW per channel.QPSK modulation.Different stream of services as data rate increases and extra capcity.p y
HSDPA (HSDPA (33.X G).X G)Stands Enhanced High speed data packet access.h h d h h h f ll hEnhancing the data rate through the following technique.5 simultaneously codes 2Mb/s.5 simultaneously codes & 16 QAM modulation 3.6Mb/s.10 simultaneously codes & 16 QAM modulation 7.2Mb/s.
20 s u ta eous y codes & 6 Q odu at o b/s15 simultaneously codes & 16 QAM modulation 14.4Mb/s.
HSDPA speed is increasing rapidly.(MIMO, 32QAM, 2 carrier coherent 80Mb/s)2
Egypt’s Mobile Spectrum AllocationEgypt’s Mobile Spectrum Allocation
GSM 900
Vodafone
Mobinil
Etisalat
Purchased & Active
Reserved for operator
MHz 880 890 902.5 915 925 935 947.5 960
UL
E‐GSM
DL
E‐GSM
Etisalat
GSM 1800
Channels 1 62 63 124 975 1023 0
MHz 1710 1715 1751 1756 1761 1766 1785 1805 1810 1846 1851 1856 1861 1880
1763 5 1858 5
Channels 512 538 716 741 766 778 791 885
DL
1763.5 1858.5
UL
UMTS
UL
MHz 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980
DL
MHz 2110 2115 2120 2125 2130 2135 2140 2145 2150 2155 2160 2165 2170
Channels 9612 9637 9662 9687 9712 9737 9762 9787 9812 9837 9862 9887
DL
Channels 10562 10587 10612 10637 10662 10687 10712 10737 10762 10787 10812 10837
TerminologiesTerminologies
UMTSUMTSUniversal mobile telecommunication system.Refer to the entire network.All h id d d i b llAll the systems can considered under its umbrella.
WCDMA (UTRAWCDMA (UTRA‐‐FDD)FDD)The Access network that based on the WCDMA‐FDD slandered .
UTRANUTRANUniversal terrestrial radio access network.Include the WCDMA access network; except for the UE (userInclude the WCDMA access network; except for the UE (user
equipment)
RANRANRadio access network
2Radio access network.Define the different types of the radio access networks (WCDMA‐GSM‐
GPRS….etc). 2
Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines
1. Before We Start
2. UMTS Introduction
4. UMTS Network Architecture.
3. WCDMA Concepts.
5. UMTS Air Interface Principles.
6. UMTS Procedures
7. UMTS services and applications
W(W)CDMA history (evolution)(W)CDMA history (evolution)
19001900 First human voice transmission (Reginald Fessenden)
19481948 J h Pi d ib CDMA M lti l i
19061906 First radio broadcast (Fessenden)
19481948 John Pierce describes CDMA Multiplexing
19491949 Claude Shannon & John Pierce describe major CDMA effects
19561956 "Anti‐multi path" RAKE receiver patented
19701970ss CDMA used in several military communication and navigation systems
19801980ss Studies for narrowband CDMA for commercial mobile networks
19931993 USA used CDMA standardised in 2nd generation
19901990ss Studies for wideband (~5 MHz) CDMA for mobile cellular systems
19961996 UMTS forum established
g
19971997 ITU requests proposals for candidate radio transmissiontechnologies for IMT‐2000 radio interface
(W)CDMA history (evolution)(W)CDMA history (evolution)
19981998 3GPP formed to develop of a joint 3G system based on evolved GSM core and UTRA air interface
19991999 ETSI starts UMTS project20032003 Commercial use of WCDMA network20052005 First commercial launch of HSDPA networkFirst commercial launch of HSDPA network
Old and New school in RF Bandwidth Utilization Old and New school in RF Bandwidth Utilization
Multiple Access different techniquesMultiple Access different techniques
CDMA optionsCDMA options
Di t d f h i CDMADi t d f h i CDMADirect sequence and freq hopping CDMADirect sequence and freq hopping CDMA
The CDMA PartyThe CDMA Party
What do YOU hear...
•If you only speak Japanese?
•If you only speak English?
•If you only speak Italian?y y p
•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?
One Cell Frequency ReuseOne Cell Frequency Reuse
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)
CDMA conceptCDMA concept
(C1D1 + Perfect orthogonally
C1 * C2 = 0
C1 * C3 = 0
(C1D1 + C2D2 + C3D3)
Perfect orthogonally
Number of users (capacity) are C1 C3 0
C1 * C1 = 1
C2 * C3 = 0
Number of users (capacity) are related to the number of codes.
Rate of codes must be higher than
C2 * C2 = 1
C3 * C3 = 1
the data. (as the code length increase the code rate increase)
So spreading must be used which p gminimize power per user
Coding Concept …Coding Concept …
Receiver and Transmitter use identical code at same time offset
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 -1PN code used
in Transmitter
x x x
Transmitter
+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1TransmittedSequence
= = =
+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 -1PN CodeUsed in Receiver
x x x
Receiver
1 1 1Divide by
+8 -8 +8
IntegrateResult
Integrate Integrate Integrate
+1 -1 +1Divide byCode Length
Coding Concept…Coding Concept…
Input Data +1 1 +1
Receiver and Transmitter use two uncorrelated codes at same time offset
Transmitter
Input Data +1 -1 +1
Orthogonal codein Transmitter
x x x
= = =+1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1 +1 –1 +1 +1 –1 -1 +1 -1
TransmittedSequence
= = =
x x x
+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 different Code
used in Receiver
x x x
= =Receiver
+1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1 +1
=
0 00
IntegrateResult
0Divide by
Integrate IntegrateIntegrate
0 00Code Length 0 0
Coding conceptCoding concept
+1
‐1
ChipChip
Rate matched baseband
Data
Code +1
‐1
ChipChip
Data xCode
+1
‐1Scrambling
Code +1DespreadingDespreading
Uu
‐1
Data +1
‐1
Interference limited system Interference limited system
Spreading concept in CDMASpreading concept in CDMA
de
Two Transmitters at the same frequency
PN Code 1Frequency
Am
plit
ud
Signal 1
Both signals combinedin the air interface
Am
plit
ude
Signal 2
PN Code 2Frequency
A
Spread SpectrumAT THE RECEIVER...
⎟⎠⎞
⎜⎝⎛=
Rate DataRate Code PN
Spread SpectrumProcessing Gain
Both signals arereceived together
AT THE RECEIVER...
PN Code 1 Signal 1 is reconstructedSignal 2 looks like noise
Spreading and Power Spectral DensitySpreading 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 p g g p p gchanges how the power is distributed over frequency
Spreading and Power Spectral DensitySpreading and Power Spectral Density
As Power of b(t) = Power of y(t)
fPSDfbPSD
Having fc >> fb we can now define Processing Gain G
fcPSDfbPSD tytb .. )()( =∴
g g
ctb
ff
PSDPSD
=∴ )(
G (processing gain) = fc/fb
fb =1/Tb (the bit rate of the input signal)
bty fPSD )(
fb =1/Tb (the bit rate of the input signal)
fc =1/Tc (the chip rate of the spreading code)
processing gain conceptprocessing gain concept
• Digital SNR: Eb/No
bb R
SE = Energy per bit (Eb) equals the average signal power (S) divided by the data bit rate (Rb)
BNN =0
Noise power density (N0)The total noise power in the signal bandwidth, divided by the signal bandwidth
Energy per bit (Eb) - to - Noise RatioThe Signal-to-Noise Ratio (SNR) times the SSMA Processing Gain
pbb
b GSNRRB
NS
NRS
NE
⋅=⎟⎟⎠
⎞⎜⎜⎝
⎛=⎟⎟
⎠
⎞⎜⎜⎝
⎛=
00
1
CDMA Rx ConceptCDMA Rx Concept
• Correlation of channel codes in receiver• Own channel correlates well, i.e. peaks (Signal)• Other channels appear as noise (Interference)• More users → increased interference
Power
• More users → increased interference
Signal (Eb)
1 Carrier (5MHz)
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 (CDMA Rx Concept (22//22))
If the BLER requiresPower
+G
+5 dB
If the BLER requiresA Eb/No of 5dB for a certain service and the processing gain (Gp) is
Gp Signal (Eb)
p g g p25dB for the service,
it means a C/I down to
Interference& Noise (No)
–20 dB
–20 dB is still acceptable
Gp
1 Carrier (5MHz)
)Rc/Rilog(10 ⋅−= NoEb
IC
Rc : Chiprate 3.84 Mc
Gp
Ri : Service bitrate
Drivers behind Spread Spectrum signals Drivers behind Spread Spectrum signals
•• SecuritySecurity
• Harder for eavesdropper to detect, jam and interfere.
•• Wider Scope of ApplicationsWider Scope of Applications
Narrow Signal
PowerWider Scope of ApplicationsWider Scope of Applications− Higher Bandwidth available for user gives more varieties
for supported applications.
•• Higher System CapacityHigher System Capacity− Depending on unique nature of codes spreading to− Depending on unique nature of codes spreading to
distinguish different users on same carrier.− Simplified system planning from a frequency reuse of
1, which allows the same RF carrier frequency to be used in every cell or sector throughout a system. y g y
•• Better system quality.Better system quality.− Enhanced RF channel performance (reduced fading) due
to unique reception techniques. − Enhanced call quality Better and more consistent sound
Spread Spectrum Signal
Frequency
Enhanced call quality. Better and more consistent sound. − A more reliable transport mechanism for wireless data
communications. − Reduced interference from other sources. − Lower transmit RF power levels, longer battery life, andLower transmit RF power levels, longer battery life, and
increased talk time for hand‐held units.
Related Terms and DefinitionsRelated Terms and Definitions
TermTerm DefinitionDefinition• Narrow Band Signal Signal occupies a relatively small bandwidth
i.e. (GSM signal has 200KHz bandwidth)
• Wide Band Signal Signal occupies relatively wide bandwidthi.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 p g g g gwith much higher bit rate
• Scrambling Converting a signal into another coded version of it keeping the same bit ratep g
Related Terms and DefinitionsRelated Terms and Definitions
• 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
Multiple users spreading and dispreadingMultiple users spreading and dispreading
Multiple users spreading and dispreadingMultiple users spreading and dispreading
Repeated Spreading and ScramblingRepeated Spreading and Scrambling
Repeated spreading and scrambling used inRepeated spreading and scrambling used in
• Channel identification
• Transmitter identification
Types of Codes in WCDMATypes 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– 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/Spreading Codes (TheWalsh functions Orthogonal codes )Channelization/Spreading 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
Properties of MProperties of M--Sequences (PN codes)Sequences (PN codes)
1- Blanca property: – Number of one’s = Number of zero + 1
2- Run property:2 Run property:The total number of runs = (N + 1) / 2
– Sequence contains one run of ones, length m– One run of zeros, length m-1, g– One run of ones and one run of zeros, length m-2– Two runs of ones and two runs of zeros, length m-3– 2m-3 runs of ones and 2m-3 runs of zeros, length 1
3 A t l ti P t3- Autocorrelation Property – The periodic autocorrelation of a ±1 m-sequence is
( ) otherwise
... 2N, N,0,
11 =
⎩⎨⎧−
=τ
τR
PN Code GenerationPN Code Generation
• PN Codes: Generation using a Shift Register
D D D D
β1 β2 β3 βN
clock
1010010010001110101...
• 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”
Generation of Scrambling CodeGeneration of Scrambling Code
• 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 BOnly 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 15 secondary codes
Properties of MProperties of M--SequencesSequences
1 0 0O/P
The output m sequence = 0011101
CLK
1 0 0
1.Balance property
No of ones = 4 , No of Zeros = 3
1 1 0
1 1 1
0 1 1
2.Run property
Total no of runs = 40 1 1
1 0 1
0 1 0
o/p = 00 111 0 1
–Sequence contains one run of ones, length m= 3
One run of zeros length m 1 = 20 0 1
–One run of zeros, length m-1 = 2
–One run of ones and one run of zeros, length m‐2 = 1
Gold Sequences
• Gold sequences constructed by the XOR of two m-sequences with the same clocking
• They can supply large number of code.y pp y g• They have very good cross correlation properties
Generation ofGeneration of Scrambling CodeScrambling Code
• Downlink Scrambling CodesU d di i i h B S i i i– Used to distinguish Base Station transmissions on Downlink
• Each Cell is assigned one and only one Primary Scrambling Codeg y y g
• 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
8192 Downlink Scrambling CodesEach code is 38,400 chips of a 218 - 1 (262,143 chip) Gold Sequence
Code Group #1 Code Group #64
Primary SC0
Secondary Scrambling
Codes
(15)
Secondary Scrambling
Codes
(15)
Secondary Scrambling
Codes
(15)
Secondary Scrambling
Codes
(15)
Primary SC7 Primary SC504 Primary SC511
( ) ( ) ( ) ( )
Scrambling CodeScrambling Code
Uplink: PN Code used to distinguish each Mobile StationDownlink: PN Code used to distinguish each Base Station
PN1 PN1
Cell Site “1” transmits using PN code 1
g
PN3 PN4
PN2 PN2
Cell Site “2” transmits using PN code 2
PN5 PN6
SSMA PN Code PlanningSSMA PN Code Planning
Spread Spectrum Code Planning Example
N
PN2
PN2
PN3
N
W E
PN2
PN1
PN2
PN3PN7
PN6 PN4
PN1
PN3PN7
PN6 PN4
PN5 PN1
PN2
PN3PN7S
PN1
PN2
PN3PN7
PN6 PN4
PN1
PN3PN7
PN6 PN4
PN5 PN1
PN2
PN3PN7
PN5 PN6 PN4
PN5
PN6 PN4
PN5
PN5 PN1
PN6 PN4
PN5
Orthogonal Code CorrelationOrthogonal Code Correlation
• Orthogonal Code correlation– Code correlated with itself ‐‐> 100% correlationCode correlated with itself > 100% correlation
– Code is correlated with another orthogonal code ‐‐> 0% correlation
– Code time alignment is essential
Autocorrelation of Walsh 34 Walsh 3460 Autocorrelation of Walsh 34, Walsh 34Integration Sum = 64 at time offset = 0
-20
02040
60
Cross-correlation of Walsh 34, Walsh 47Integration Sum = 0 at time offset = 0
10 20 30 40 50 60-60-40
4060
Integration Sum = 0 at time offset = 0
-60-40-20
02040
Poor cross-correlation properties at time shifts other than zero!10 20 30 40 50 60
Orthogonal Codes conceptsOrthogonal Codes concepts
• When you send data using Orthogonal Codes...Orthogonal Code
Transmitted “chips”Data
Orthogonal Code
User 1 Data:
1 0 1
XOR with Walsh Code
1010
User 1 Walsh-spread Data:
0101 1010 0101
You send one orthogonal (e.g., Walsh) code for every data bit!
If you want to send a “0”, you transmit the assigned Walsh Code
If you want to send a “1”, you transmit the inverted Walsh Code
Orthogonal Codes conceptsOrthogonal Codes concepts
• Orthogonal Code Transmitter
Data Channel 1
0 1 0
Data Channel 2
XOR with OC1
( 1111 )
XOR with OC2
After XOR
(1111)(0000)(1111)
After D/A Mapping
(----)(++++)(----)
After XOR After D/A Mapping
0 0 1 ( 1100 )∑
Data Channel 3
1 0 1
XOR with OC3
( 1010 )
(1100)(1100)(0011) (--++)(--++)(++--)
After XOR
(0101)(1010)(0101)
After D/A Mapping
(+-+-)(-+-+)(+-+-)
C it T itt d D t
Data Channel 4
0 0 0
XOR with OC3
( 1001 )
After XOR
(1001)(1001)(1001)
After D/A Mapping
(-++-)(-++-)(-++-)
Composite Transmitted Data:
(-2 -2 +2 -2) (-2 +2 +2 +2) (0 0 0 -4)4-chip Orthogonal Code Set
1) 1 1 1 12) 1 1 0 03) 1 0 1 03) 1 0 1 04) 1 0 0 1
Orthogonal Codes Orthogonal Codes conceptsconcepts
• Orthogonal Code ReceiverComposite Received Data:
4-chip Orthogonal Code SetAnalog representation)
1) -1 -1 -1 -12) -1 -1 +1 +1
Integrate & Result:
“Correlation”
(-2 -2 +2 -2)(-2 +2 +2 +2)(0 0 0 -4)
XOR with OC1
3) -1 +1 -1 +14) -1 +1 +1 -1
Map A→DIntegrate &
Normalize
Integrate &
Result:
1 -1 1
Result:
XOR with OC1
(-1 -1 -1 -1)
XOR with OC2
Map A→D
0 1 0
Map A→D
Normalize
Integrate &
Normalize
1 1 -1
Result:
-1 1 -1
(-1 -1 +1 +1)
XOR with OC3
(-1 +1 -1 +1)
0 0 1
Map A→D
1 0 1
Integrate &
Normalize
Result:
1 1 1XOR: Exclusive-Or multiplication
( )
XOR with OC4
(-1 +1 +1 -1)
Map A→D
0 0 0
Integrate: Sum four consecutive values after XOR
Normalize: Multiply by [ 1 / code length]
Orthogonal Codes conceptsOrthogonal Codes concepts
Downlink: Orthogonal Codes used to distinguish data channelsC i f h B St ti
OC1, OC2OC3, OC4
Coming from each Base Station
OC5, OC6, OC7
Uplink: Orthogonal Codes used to distinguish data channelscoming from each Mobile Station
OC1 , OC2, OC3OC1, OC2
OC1, OC2, OC3, OC4
Orthogonal Code GenerationOrthogonal Code Generation
• Generation of Orthogonal (Walsh) Codes1
11 1011 10
1111 1100 1010 1001
11111111 11110000 11001100 11000011 10101010 10100101 10011001 1001011011111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110
Digital/Analog Mapping
logic 0 ↔ analog +1logic 1 ↔ analog - 1
1100110011001100
Orthogonal Codes conceptsOrthogonal Codes concepts
• orthogonal Code Space: 5 users; one user has 4x data bandwidth
Chi R t 3 840 M1
User with 2x Bit Rate
1 92 MSymbol/s
Chip Rate = 3.840 Mcps
11 101.92 MSymbol/s11 10
1111 1100 1010 1001
11111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110
= Unusable Code Space
480 kSymbol/s 480 kSymbol/s
11111111 11110000 11001100 11000011 10101010 10100101 10011001 10010110
Orthogonal Codes Orthogonal Codes conceptsconcepts
• Spreading Factor=Processing Gain= Rc/Rb
• Different spreading is done according to the service bit rate as the chip rate is constant.
٧٠
Code Locking Concept (PN Codes)Code Locking Concept (PN Codes)
• PN codes is generated not stored
• Synchronization between Node B and UEl l d dis extremely important to correctly decode
original information
WCDMA bil C d L ki• WCDMA mobiles use Code Lockingcircuitry to lock on Scrambling code.
Code Locking Concept (Orthogonal Codes)Code Locking Concept (Orthogonal Codes)
• TX, RX use same codes and same time offset
• Orthogonal Codes 100% gcorrelation
• TX, RX use same codes, but different time offset
• Orthogonal Codes Unpredictable results Orthogonality lost
• TX, RX use different codes• Orthogonal Codes 0% Correlation
Code CorrelationCode Correlation
Case I: Autocorrelation using a PN CodeReceiver and Transmitter use identical code at same time offset
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 -1PN code used
in Transmitter
x x x
Transmitter
+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1TransmittedSequence
= = =
+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 -1PN CodeUsed in Receiver
x x x
Receiver
1 1 1Divide by
+8 -8 +8
IntegrateResult
Integrate Integrate Integrate
+1 -1 +1Divide byCode Length
Code CorrelationCode Correlation
Case II: Cross-Correlation using PN CodesReceiver and Transmitter use different codes
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 -1PN code used
in Transmitter
x x x
Transmitter
+1 –1 +1 +1 –1 -1 +1 -1 -1 +1 -1 -1 +1 +1 -1 +1 +1 –1 +1 +1 –1 -1 +1 -1TransmittedSequence
= = =
-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 CodeUsed in Receiver
x x x
= = =Receiver
-4 0 2
IntegrateResult
Divide by
Integrate Integrate Integrate
-0.5 0 0.25Divide by
Code Length
Code CorrelationCode Correlation
Input Data +1 1 +1
Case III: Correlation using Orthogonal Codes(a) Same Orthogonal code (b) Different Orthogonal codes (c) Same code with non-zero time offset
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 -1Orthogonal code
in Transmitter
x x x
= = =-1 +1 –1 +1 +1 –1 +1 -1 +1 –1 +1 –1 –1 +1 –1 +1 -1 +1 –1 +1 +1 –1 +1 -1Transmitted
Sequence
= = =
x x x
1 Chip shift
-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 Codeused in Receiver
x x x
= = =Receiver
8 0 -4
IntegrateResult
+1 0 0 5Divide by
Integrate Integrate Integrate
+1 0 -0.5Code Length
Scrambling and Channeliztion codesScrambling and Channeliztion codes
SummarySummary
SC1
SC1SC1
SC1
SC1
Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines
1. Before We Start
2. UMTS Introduction
4. UMTS Network Architecture.
3. WCDMA Concepts.
5. UMTS Air Interface Principles.
6. UMTS Procedures
7. UMTS services and applications
Different UMTS releasesDifferent UMTS releases
Release Release 99 99 feature. feature. New Radio Interface (UTRA)
FDD and TDD at 3.84 Mcps.GSM/GPRS HandoverGSM/GPRS Handover.Support for Multi-call (CS & PS) simultaneously.Location service over Air Interface.Basic UMTS security.yCore network was compatible with the GSM/GPRS networks
Release Release 4 4 feature feature TDD at 1 28 McpsTDD at 1.28 Mcps.Evolution of core network transport to IP.
ReleaseRelease 55 featurefeatureRelease Release 5 5 feature feature Evolution of UTRAN transport to IPIP based Multimedia service.High-Speed Downlink Packet access (HSDPA).g p ( )
WCDMA RWCDMA R99 99 Network ArchitectureNetwork ArchitecturePSTNISDN
GSM /GPRS BSS
BTS
BSC
MSC/VLR GMSC
HLR/AUC
ISDN
BTS
RNC
PCU
SMS
SCE
HLR/AUC
SS7
NodeB SCP
SMS
SGSN
GPRS backbone/ Internet,Intranet
SGSN GGSN
User UTRAN Network Core NetworkEquipment Domain Access Network
Domain
Access stratum
Non Access stratum
Access stratum
WCDMA RWCDMA R99 99 Network ArchitectureNetwork Architecture
11--Core Network DomainCore Network Domain
Structure of the CN.Structure of the CN.
11--Core Network DomainCore Network Domain
F ti f th CNF ti f th CNFunction of the CN.Function of the CN.Connection Management (CM),
Provides the bearer services and the procedures for circuit-switched connections (RAB handling; Call control handling).switched connections (RAB handling; Call control handling).
Session Management (SM)Responsible for the set up, monitoring and release of a packet-
switched connection (PDP handling).Mobility Management (MM)
Determine the location of a User Equipment so a connection can be set up.
Circuit switching (Detach; Ideal and activeCircuit switching (Detach; Ideal and activelocation update and paging).Packet switching (Idle; ready and standby routing area update and paging).
Handling the mobility of the user in order to keep cell continuity in the active mode.
11--Core Network DomainCore Network Domain
Connection management.Connection management.
11--Core Network DomainCore Network Domain
S i M tS i M tSession ManagementSession Management
11--Core Network DomainCore Network Domain
M bilit M tM bilit M tMobility ManagementMobility Management
11--Core Network DomainCore Network DomainCircuit Switching DomainCircuit Switching Domain
MSC FunctionMSC FunctionSignaling switching and call routing to or from MS.Charging.Service provisioningService provisioning.Control of connected RNC’s.One MSC controls more than one RNC.
GMSC FunctionGMSC FunctionAccess to PSTN.Access to PSTN.Provides the gateway functionality/Interface
to other networks.
11--Core Network DomainCore Network DomainCircuit Switching DomainCircuit Switching Domain
VLR FunctionVLR FunctionAssociated with MSCSubscriber Management in MSC area.Authentication co ordinationAuthentication co-ordination.Commands start of ciphering.
VLR DataVLR Data
MSC/VLR
VLR Data.VLR Data.A temp data base that holding the following information
Subscriber data from HLR.MSISDN; IMSI…etc.Services available and restrictions.
Temp subscriber information.TMSI; LAI; triples….etc.
The VLR hold these data for the subscriber included in theThe VLR hold these data for the subscriber included in the MSC area only.
11--Core Network DomainCore Network DomainRegister and Service domainRegister and Service domain
HLR FunctionHLR FunctionThe HLR is a centralized (unique) network database that stores and manages all mobile subscriptions.
IMSI, MSISDNServices subscribedService restrictions (e.g. roaming restrictions)Parameters for additional servicesParameters for additional servicesInfo about user equipment (IMEI)Authentication data
Temporary informationTemporary information Link to current location of the user:Current VLR address (if avail)Current MSC address (if avail)MSRN (if user outside PLMN)
11--Core Network DomainCore Network DomainRegister and Service domainRegister and Service domain
Other nodes for the register domain.Other nodes for the register domain.AUC: authentication center.EIR: equipment identity register. IN: intelligent network.BGW: belling gateway.SMSC: short message service center.
11--Core Network DomainCore Network DomainPacket switching domainPacket switching domain
SGSN FunctionSGSN FunctionForwards incoming and outgoing IP packets addressed
to/from a mobile station that is attached within the SGSN service areaservice area.
Provides packet routing and transfer to and from the SGSN service area.
Ciphering and authenticationSession managementMobility managementLogical link management toward the MSOutput of billing dataOutput of billing data.
SGSN
11--Core Network DomainCore Network DomainPacket switching domainPacket switching domain
GGSN FunctionGGSN FunctionThe interface towards the external IP
packet networks.pActs as a router Exchanges routing information with the
external network.GPRS session managementGPRS session management,
communication setup toward external network.
Output of billing data.
22. Access Network Domain. Access Network Domain
22--Acess NetworkAcess Network
F ti f th A t kF ti f th A t kFunction of the Access network.Function of the Access network.Responsible of the radio resources management.Consists of several Radio network subsystem (similar of BSS in GSM).
One RNCOne RNC.Several node Bs.
22--Acess NetworkAcess NetworkRNC functionRNC function
F ti f th RNCF ti f th RNCFunction of the RNC.Function of the RNC.Control several node Bs/ interface with the core network (MSC/SGSN).Radio resources management.Admission and congestion control.Admission and congestion control.Handover and power control (outer loop).Ciphering/deciphering. Can softly be divided into 3 types
CRNC ControlCRNC ControlSRNC ServingDRNC Drift
22--Acess NetworkAcess NetworkRNC functionRNC function
P C t l i RNCP C t l i RNCPower Control in RNC.Power Control in RNC.Open loop power controlclosed loop power controlOuter loop power controlOuter loop power control
22--Acess NetworkAcess NetworkNode B functionNode B function
F ti f th N d BF ti f th N d BFunction of the Node B.Function of the Node B.Contains the RF equipment that provide
the radio link in the air interface.More intelligent than BTS.More intelligent than BTS.Perform spreading/dispreading, channel
coding, also responsible of a part of the power control (inner loop).
Ciphering using the ciphering key.Records and passes to the RNC the
Signal strength measurements
Mapping of Transport channels into physical channels
33-- User Equipment domain User Equipment domain
Function of the User Equipment domain .Function of the User Equipment domain .The end user node; that provide the services/application to the users.The new generation of UMTS phones will combine the advantages of g p g
wireless communication with the demand for multimedia applications Consists of.
User Terminal.
UMTS Subscriber Identity Module (USIM)
UE
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
F ti f UTF ti f UTFunction of UT.Function of UT.Radio transmission termination.Radio channel management.Speech encoding / decoding.Speech encoding / decoding.Flow control of data.Mobility management.Call control. Performance meas rement of radio linkPerformance measurement of radio link.SIM card interface service provider and network registration/ deregistrationlocation updatepsetup of connectionless / connection-oriented servicesunalterable equipment identification (IMEI). basic identification of the User Equipment's capabilitiesemergency calls without a SIMemergency calls without a SIM execution of algorithms required for authentication and encryption
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
N F ti f UTN F ti f UTNew Functions of UT.New Functions of UT.
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
M lti d i tM lti d i tMultimode user equipmentMultimode user equipment
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
M lti d i tM lti d i tMultimode user equipmentMultimode user equipment
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
T f i t (TT f i t (T 11 / T/ T 22))Types of user equipment (Type Types of user equipment (Type 11 / Type / Type 22))
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
T f i t (TT f i t (T 33 / T/ T 44))Types of user equipment (Type Types of user equipment (Type 33 / Type / Type 44))
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
IMEI f t d f tiIMEI f t d f ti
Final Assembly Codes (FAC)
IMEI format and function.IMEI format and function.UE is uniquely identified by the IMEI.Used by the EIR for terminal authentication and for capabilities identification
TAC(6 digits)
FAC (2 digits)
SNR (6 digits)
SVN (2 digits)
Final Assembly Codes (FAC)
01 ,02 AEG
07 ,40 MotorolaTAC: Type Approval CodeTAC: Type Approval Code10 ,20 Nokia
40,41,44, Siemens
l l
TAC: Type Approval CodeTAC: Type Approval CodePlaces that is centrally assigned by a GSM body.
47 Optional International
51 Sony
51 Siemens
SNR: Serial NumberSNR: Serial NumberUnique serial number assigned by the manufacturer
51 Ericsson
60 Alcatel
SVN: Software version NumberSVN: Software version NumberRefer to the version of software
33-- User Equipment domain User Equipment domain User TerminalUser Terminal
USIM USIM function.function.
Stores user addressesIMSI,MSISDN,TIMSI, rooming, etc
Authentication and encryption features
subscriber’s secret authentication key (Ki)subscriber s secret authentication key (Ki)
Security Algorithm & Keys (for Authentication, Ciphering,..).
PersonalizationSIM t fil ( b ib d i )SIM stores user profile (subscribed services)RAM available for SMS, short numbers, user’s directory, etcProtection codes PIN ,PUK
Core Network Evolution.Core Network Evolution.RR99 99 Vs RVs R44
SCP HLR SCP HLR
CS domain evolution
TUP/ISUP
MAP Over TDM MAP Over TDM/IP
ATM/IP/TDMMSC MSC
TDMMSC Server
ATM/IPMGW MGW
MSC ServerTUP/ISUP
ATM/IP
ATM/IP/TDM
RAN RAN RAN RAN RAN RAN
ATM/IP
R99 R4
PS domain structure remain unchangedPS domain structure remain unchanged
WCDMA RWCDMA R4 4 Network ArchitectureNetwork Architecture
MGWMGW MGWMGW
IP/ATM Backbone
PSTN
HLR/AUC
MSC Server GMSC Server
PSTNISDN
NodeB
RNC
SMS
SCE
HLR/AUC
SS7
UTRAN SCP
SMS
SGSNGGSN
GPRS backbone Internet,IntranetUTRAN Network
GGSNUser
Equipment Domain
Access Network Domain
Access stratumCore Network
Access stratumNon Access stratum
MSC ServerMSC Server
MSC server.MSC server.Call control and routing for mobile-
originated and mobile-terminated calls; gMobility managementintegrates with (VLR) which holds
location information;Providing authentication functions;Providing authentication functions;terminates signaling
Media GatewayMedia Gateway
Media gateway server.Media gateway server.This translates media traffic between different
types of network.ypTermination of bearer channels;MSC server is able to support several MWGs;
SummarySummary
Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines
1. Before We Start
2. UMTS Introduction
4. UMTS Network Architecture.
3. WCDMA Concepts.
5. UMTS Air Interface Principles.
6. UMTS Procedures
7. UMTS services and applications
WCDMA Frequency AllocationsWCDMA Frequency AllocationsWCDMA Frequency AllocationsWCDMA Frequency Allocations
2025 2110FDD UPLINK TDD FDD DOWNLINK
1920 1980 2010 2170
WCDMA /EUROPE
1850 1910
FDD UPLINK1930 1990
WCDMA / USA FDD DOWNLINKTDD
TDD1900
2025 2110
IMT-2000 MSS MSS IMT-2000 MSS MSS
1885 1980 2010 2160 2170 2200
ITU/WARC-95
2025 2110
IMT-2000 MSS IMT-2000 MSS
1900 1980 2010 2170 2200
DECT
1880
Europe
2025 2110
IMT-2000 MSS Terrestrial MSS
1918.1 1980 2010 2170 2200
PHS
18951885
Japan
2025 2110
MSS MSS
1900 1980 2010 2170 2200
FDD WLL
1880
CDMA
1865 1920 1945 1960
TDD WLL CDMA FDD
WLLChina
2025 21101900 1980 2010 2170 220018801865 1920 1945 1960
2025 2110
MSS
2185 2200
A
1850 1910 1930 1990
D B E F C A D B E F C MSS BroadcastAuxiliary Reserved
2150
USA
Part 4: 113 of 65
WCDMA StandredsWCDMA StandredsWCDMA StandredsWCDMA Standreds
3GPP WCDMA O i• 3GPP WCDMA OverviewBoth FDD (2x 5 MHz) and TDD (1x 5 MHz)modes supported
• Operation specified in bands between 1850 and 2170 MHzBS time synchronization not required for FDD mode
• GPS not required• Fast Synchronization Codes allow asynchronous operation and handoverS h i i ll d ll f i i i i f• Synchronous operation is allowed; allows faster acquisition, interference reduction
Multi‐Code and Variable Spreading Factor modes supportedNetwork interface compatible with GSM ‐MAP / GPRSNetwork interface compatible with GSM MAP / GPRS
• * To be made compatible with ANSI‐41 per OHG requirementPhysical Parameters:
• Chip rate = 3.840 Mcps• RF Bandwidth = 5 MHz• Physical Layer data rates of 15, 30, 60, 120, 240, 480, 960, and 1920 kb/sec• Payload data rates of 12.2, 64, 128, 144, 384, 768, and 2048 kb/sec• Frame length = 10 mSec and15 time slot = 0.667 mSec• Fast Power Control: Bi‐directional; 1500 updates/sec
WCDMA moduleWCDMA moduleWCDMA moduleWCDMA module
WCDMA Physical ChannelsWCDMA Physical ChannelsWCDMA Physical ChannelsWCDMA Physical Channels
P-CCPCH- Primary Common Control Physical ChannelSCH - Synchronization Channel
Channels broadcast to all UE in the cell
P-CPICH - Primary Common Pilot ChannelS-CPICH - Secondary Common Pilot Channel(s)
PICH - Paging Indicator Channel
Paging Channels
S-CCPCH - Secondary Common Control Physical Channel
BaseStation
(BS)
UserEquipment
PICH Paging Indicator Channel
PRACH - Physical Random Access Channel
AICH - Acquisition Indicator Channel
Random Access and Packet Access Channels
( )(UE)PCPCH – Physical Common Packet Channel
AP-AICH - Access Preamble Acquisition Indicator ChannelCD/CA-AICH -Collision Detection/Ch.Assignment Indicator Ch.CSICH - CPCH Status Indicator Channel
DPDCH - Dedicated Physical Data Channel
DPCCH - Dedicated Physical Control Channel
PDSCH Ph i l D li k Sh d Ch l
Dedicated Connection Channels
PDSCH - Physical Downlink Shared Channel
UMTS Channels mappingUMTS Channels mappingUMTS Channels mappingUMTS Channels mapping
Release Release 4 4 ChannelsChannelsRelease Release 4 4 ChannelsChannels
Release Release 5 5 channelschannelsRelease Release 5 5 channelschannels
PCCPCHPCCPCHPCCPCHPCCPCH
PCCPCHPCCPCHPCCPCHPCCPCH
PCCPCHPCCPCHPCCPCHPCCPCH
CPICHCPICHCPICHCPICH
(P & S)(P & S)‐‐CPICHCPICH(P & S)(P & S)‐‐CPICHCPICH
SCHSCHSCHSCH
SCCPCHSCCPCHSCCPCHSCCPCH
PICHPICHPICHPICH
PRACH and FACHPRACH and FACHPRACH and FACHPRACH and FACH
AICHAICHAICHAICH
SCCPCHSCCPCHSCCPCHSCCPCH
DPDCHDPDCH
DPDCH & DPCCHDPDCH & DPCCHDPDCH & DPCCHDPDCH & DPCCH
DL DPDCHDL DPDCHDL DPDCHDL DPDCH
UL DPDCHUL DPDCHUL DPDCHUL DPDCH
UL DPDCHUL DPDCHUL DPDCHUL DPDCH
Downlink Data RatesDownlink Data RatesDownlink Data RatesDownlink Data Rates
• Variable Data Rates on the Downlink: ExamplesBits/Frame Bits/ Slot Channel Bit
R t Channel S b l
SF
DPCCH Rate
(kbps) Symbol
Rate (ksps)
TOTAL DPDCH DPCCH TOTAL DPDCH
TFCI TPC PILOT
15 7 5 512 150 60 90 10 4 0 2 4 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
Channel Coding
Coded Data1.920 Mb/sec
(19,200 bits per 10 mSec frame)
S/P Converter
(OVSF codes at 3.84 Mcps)
960 kb/sec
per 10 mSec frame)
Downlink DPDCH/DPCCH Slot FormatsDownlink DPDCH/DPCCH Slot FormatsDownlink DPDCH/DPCCH Slot FormatsDownlink DPDCH/DPCCH Slot Formats
DPDCHBits/Slot
DPCCHBits/Slot
SlotFormat
#i
ChannelBit Rate(kbps)
ChannelSymbol
Rate(k )
SF Bits/Slot
Transmittedslots per
radio frameN
3GPP TS 25.211¶ 5.3.2
(ksps) NData1 NData2 NTPC NTFCI NPilotNTr
0 15 7.5 512 10 0 4 2 0 4 150A 15 7.5 512 10 0 4 2 0 4 8-140B 30 15 256 20 0 8 4 0 8 8-141 15 7.5 512 10 0 2 2 2 4 15
1B 30 15 256 20 0 4 4 4 8 8 14
Notes:
1) Z TFCI l t f t 1B 30 15 256 20 0 4 4 4 8 8-142 30 15 256 20 2 14 2 0 2 15
2A 30 15 256 20 2 14 2 0 2 8-142B 60 30 128 40 4 28 4 0 4 8-143 30 15 256 20 2 12 2 2 2 15
3A 30 15 256 20 2 10 2 4 2 8-143 60 30 128 0 2 8 1
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
14 480 240 16 320 56 232 8 8* 16 1514A 480 240 16 320 56 224 8 16* 16 8-14
3B 60 30 128 40 4 24 4 4 4 8-14 compressed mode operation
14B 960 480 8 640 112 464 16 16* 32 8-1415 960 480 8 640 120 488 8 8* 16 15
15A 960 480 8 640 120 480 8 16* 16 8-1415B 1920 960 4 1280 240 976 16 16* 32 8-1416 1920 960 4 1280 248 1000 8 8* 16 15
16A 1920 960 4 1280 248 992 8 16* 16 8-14
Part 4: 137 of 65
Uplink DPDCH/DPCCHUplink DPDCH/DPCCHUplink DPDCH/DPCCHUplink DPDCH/DPCCH
• Uplink DPDCH/DPCCH Slot Formats 3GPP TS 25.211 ¶ 5.2.1
DPDCH (Dedicated Physical Data Channel) Slot Formats
Slot Format #i Channel Bit Rate (kbps)
Channel Symbol Rate (ksps)
SF Bits/ Frame
Bits/ Slot
Ndata
0 15 15 256 150 10 10 1 30 30 128 300 20 20 2 60 60 64 600 40 40 3 120 120 32 1200 80 80
DPDCH (Dedicated Physical Data Channel) Slot Formats
4 240 240 16 2400 160 160 5 480 480 8 4800 320 320 6 960 960 4 9600 640 640
Slot Channel Bit Channel Symbol SF Bits/ Bits/ Npilot NTPC NTFCI NFBI T ransmitted DPCCH (Dedicated Physical Control Channel) Slot Formats
Format #i
Rate (kbps) y
Rate (ksps) Frame Slot p ot C C
slots per radio frame
0 15 15 256 150 10 6 2 2 0 15 0A 15 15 256 150 10 5 2 3 0 10-14 0B 15 15 256 150 10 4 2 4 0 8-9 1 15 15 256 150 10 8 2 0 0 8-15 2 15 15 256 150 10 5 2 2 1 15
2A 15 15 256 150 10 4 2 3 1 10-142A 15 15 256 150 10 4 2 3 1 10-142B 15 15 256 150 10 3 2 4 1 8-9 3 15 15 256 150 10 7 2 0 1 8-15 4 15 15 256 150 10 6 2 0 2 8-15 5 15 15 256 150 10 5 1 2 2 15
5A 15 15 256 150 10 4 1 3 2 10-14 5B 15 15 256 150 10 3 1 4 2 8-9
Part 4: 138 of 65
UMTS TimingUMTS Timing
UMTS timingUMTS timing
Physical channels timingPhysical channels timing
Physical Channels summaryPhysical Channels summary
WCDMA Downlink Physical ChannelsWCDMA Downlink Physical Channels
• Common Downlink Physical Channels
• P‐CCPCH Primary Common Control Physical Channel‐ 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 Secondary Common Control Physical Channel‐ Transmits idle‐mode signaling and control information to
UE’s• P‐CPICHCommon Pilot Channel • S‐CPICHSecondary Common Pilot Channel (for sectored cells)• PDSCH Physical Downlink Shared Channel
‐ Transmits high‐speed data to multiple users
• Dedicated Downlink Physical Channels• DPDCH Dedicated Downlink Physical Data Channel• DPCCH Dedicated Downlink Physical Control Channel
‐ Transmits connection‐mode signaling and control to UE’s
WCDMA Downlink Physical ChannelsWCDMA Downlink Physical Channels
• Downlink Indication ChannelsAICH (Acquisition Indicator Channel)
• Acknowledges that BS has acquired a UE Random Access attempt• Acknowledges that BS has acquired a UE Random Access attempt• (Echoes the UE’s Random Access signature)
PICH (Paging Indicator Channel)• Informs a UE to monitor the next paging frame
AP‐AICH (Access Preamble Acquisition Indicator Channel)• Acknowledges that BS has acquired a UE Packet Access attempt• (Echoes the UE’s Packet Access signature)
CD/CA ICH (C lli i D t ti /Ch l A i t I di t Ch l)CD/CA‐ICH (Collision Detection/Channel Assignment Indicator Channel)• Confirms that there is no ambiguity between UE in a Packet Access attempt• (Echoes the UE’s Packet Access Collision Detection signature)• Optionally provides available Packet channel assignments p y p g
CSICH (CPCH Status Indicator Channel)• Broadcasts status information regarding packet channel availability
WCDMA Uplink Physical ChannelsWCDMA Uplink Physical Channels
• Uplink Physical Channels
Common Uplink Physical Channels• PRACH Physical Random Access ChannelPRACH Physical Random Access Channel
‐ Used by UE to initiate access to BS
• PCPCH Physical Common Packet Channel‐ Used by UE to send connectionless packet data
Dedicated Uplink Physical Channels• DPDCH Dedicated Physical Data ChannelDPDCH Dedicated Physical Data Channel
• DPCCH Dedicated Physical Control Channel‐ Transmits connection‐mode signaling and control to BS
WCDMA Downlink (FDD)WCDMA Downlink (FDD)
BCCHBroadcast Control Ch
BCHBroadcast Ch
P‐CCPCH(*)Primary Common Control Physical Ch
Logical Channels(Layers 3+)
Transport Channels(Layer 2)
Physical Channels(Layer 1)
CPICHCommon Pilot Channel
Null Data
Data Encoding
S/P
S/P
Cch 256,0
PSC
Sync Codes(*)Gain
Broadcast Control Ch.
PCCHPaging Control Ch.
CCCHCommon Control Ch.
Broadcast Ch.
PCHPaging Ch.
FACHForward Access Ch.
Primary Common Control Physical Ch.
S‐CCPCHSecondary Common Control Physical Ch.
SSCi
DPCH (Dedicated Physical Channel)CTCHCommon Traffic Ch.
Data Encoding
Data Encoding
Encoding
S/P
Cch
Cch 256,1
GS
GP ΣGain
Gain
SCH (Sync Channel)
DCCHDedicated Control Ch.
DPDCH (one or more per UE) Dedicated Physical Data Ch.
DownlinkRF Out
DPCH (Dedicated Physical Channel)One per UE
Common Traffic Ch.
S/P
Cell‐specificScrambling
Code
I+jQI/Q
IC Σ
Σ FilterGain
DTCHDedicated Traffic Ch. 1
DCHDedicated Ch.
Data Encoding
MUX
MUX
CCTrCHDCHDedicated Ch.
Data Encoding
DTCHDedicated Traffic Ch. N
DCHDedicated Ch.
DPCCH (one per UE)Dedicated Physical Control Ch.Pilot, TPC, TFCI bits
DSCHDownlink Shared Ch.
Data Encoding
Data Encoding
PDSCHPhysical Downlink Shared Channel
AICH
S/P
/Modulator
Q
Cch
Cch Σ
* 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 timeslot
FilterGain
Gain
AICH (Acquisition Indicator Channel)
PICH (Paging Indicator Channel )
Access Indication data
Paging Indication bits
AP‐AICH(Access Preamble Indicator Channel )
Access Preamble Indication bits
CSICH (CPCH Status Indicator Channel )
CPCH Status Indication bits
S/P
S/P
S/P
S/P
C
Cch
Cch
Cch
P‐CCPCH transmits only during the remaining bits of each timeslot
Gain
Gain
Gain
GainCD/CA‐ICH (Collision Detection/Channel Assignment )
CPCH Status Indication bits
Cch
S/PCch Gain
Gain
WCDMA Uplink (FDD)WCDMA Uplink (FDD)
Logical Channels(Layers 3+)
Transport Channels(Layer 2)
Physical Channels(Layer 1)
Σ
CCCHCommon Control Ch.
RACHRandom Access Ch.
PRACHPhysical Random Access Ch.
Data Coding
Chd Gd
RACH Control Part
UplinkUE
ScramblingCode
Chc
DTCH (packet mode)Dedicated Traffic Ch.
CPCHCommon Packet Ch.
PCPCHPhysical Common Packet Ch.
Data Coding
Gc j
Σ
Chd Gd
RACH Control Part
RF OutCode
I+jQ I/QMod.
Q
IFilter
Filter
DPDCH #1Chd,1 Gd
Chc
Σ
Gc j
PCPCH Control Part
Σ
CCTrCH
ΣI
DPDCH #1Dedicated Physical Data Ch.
DPDCH #3 (optional)Dedicated Physical Data Ch.
DPDCH #5 (optional) Dedicated Physical Data Ch.
DPDCH #2 (optional)
Chd,3 Gd
Chd,5 Gd
Chd,2 Gd
Σ
DCCHDedicated Control Ch.
DTCHDedicated Traffic Ch. 1
DCHDedicated Ch.
Data Encoding M
UX
CCTrCH
DCHDedicated Ch.
Data Encoding
DPDCH #2 (optional) Dedicated Physical Data Ch.
DPDCH #4 (optional) Dedicated Physical Data Ch.
DPDCH #6 (optional) Dedicated Physical Data Ch.
ΣQ
Chd,4 Gd
Chd,6 Gd
Chc Gd
Σ
j
DTCHDedicated Traffic Ch. N
DCHDedicated Ch.
Data Encoding
Part 4: 147 of 65
DPCCHDedicated Physical Control Ch.Pilot, TPC, TFCI bits
c d
UMTS U Cell statusUMTS U Cell status
UMTS UMTS U Cell U Cell statusstatus
Cell_DCH
When we have a dedicated channel open for a subscriber (for example, if we are usingid ) th t b ib i i C ll DCH t t I thi t t th UE i divideo), we say that subscriber is in Cell_DCH state. In this state the UE is sendingmeasurement reports to the network, thus the system can control the dedicated bearerand perform handovers.
Cell_FACH
If the mobile is only sending small pieces of information for exampleIf the mobile is only sending small pieces of information, for exampleInternet based traffic or for signalling, then the RRC can be in a mode known as Cell_FACHand is different from the previous state as no dedicated channel is used. The network doesnot perform handovers as the mobile moves from one cell to another. The UE just informsthe network of its current location.
UMTS UMTS U Cell U Cell statusstatus
Cell_PCH
In addition to the Cell FACH, if the network finds that the bearer is not being used for a long_ , g gtime, it can move the connection to a Cell_PCH mode (Paging Channel), where the mobile isstill know to a cell level but can only be reached via the PCH..
URA_PCH
The final state is the URA_PCH. This state is similar to the Cell_PCH. But, instead ofmonitoring the connection on a cell level, it is now on a RNC level.
Course OutlinesCourse OutlinesCourse OutlinesCourse Outlines
1. Before We Start
2. UMTS Introduction
4. UMTS Network Architecture.
3. WCDMA Concepts.
5. UMTS Air Interface Principles.
6. UMTS Procedures
7. UMTS services and applications
Data transmissionData transmission
The TDMA Transmitter
Sync. Bits
The Multiplexer allows various data channels to share the same timeslot.
Control/Signaling
Data
Error Protection
Timeslot
The timeslot selector allows multiple transmitters to share the same carrier frequency, by assigning a unique timeslot to each transmitter.
Data Multiplexer Transmit
G ti g
Filtering+
RF
RF Out
Selector
VocoderError
ProtectionGating RF
Modulation
User Data Channel 1
Error Protection
User Data Error Channel N Protection
The CDMA Transmitter
Sync. Bits
Orthogonal Code 1
Orthogonal Codes provide unique identification of each data channel
Control/Signaling
Data
Bits
Error Protection
Spread Spectrum (PN) Codes provide unique identification of each transmitter
Orthogonal Code 2
Filtering+
RF Out
Linear
S ti
Data
VocoderError
Protection
SpreadSpectrum
(PN or Gold)Code
Orthogonal Code 3
RF Modulation
Summation
User Data Channel 1
Error Protection
otect o
U 1
Orthogonal Code 4
Channel 1 Protection User 1
User 2
User 3
...Orthogonal
Code N
User Data Channel N
Error Protection
Frequency
Cellular CDMA Transmitter
Orthogon
Pre-coded data (bits)
Symbols Chips
Pulse
Data Channel
1
Spread Spectrum Code
(PN Code or Gold Code)
FEC Coding
Orthogonal Code 1
CRC Coding
Inter-leaving D/A SSC_QSSC_I
I I IShaping Filter
RF Out
D t
Linear
Summation
Orthogonal Code N
1:2Demux
Pulse Shaping Filter
I/Q Modulato
r
Complex Multiplie
r (I + jQ)
I
Q
I
Q
I
Q
Data Channel
N
CRC Coding
FEC Coding
Inter-leaving D/A
Allows for error
detection in the receiver
Allows for error
correction in the receiver
Improves error
correction in the
receiver
Gives a unique
identity to each data
stream
Maps digital bits to analog signals
Provides 2x higher data rate
(WCDMA,
Gives a unique identity to this
transmitter
Contains transmitte
d frequency spectrum
Allows both signals from 1:2 Demux to share
the same RF bandwidthreceiver receiver stream
0 → +1
1 → -1
(cdma2000 downlink)
spectrum bandwidth
Voice Coding
• VocodingHuman Voice:
‘ss’, ‘ff’, ‘sh’ … ~20% of time‘ah’, ‘v’, ‘mm’ , … ~80% of time
Voice Re-Synthesis at the Receiver
White Noise Generator
Noise
H(s)
SpeechVocoder
Pulse GeneratorΣ
Noiseparameters
Pitch Filter poles correspond to
SpeechOutput
H(s)
Transmitted Parameters8~12 kb/s typical,
parameters correspond to resonances of the
vocal tract
vs.64 kbps for log-PCM32 kbps for ADPCM
ACELP/AMR Voice Coding
A/D
Linear Predictive
Coding(LPC)
Voice, Tone Activity
Detectors
FilterCodebook
SpeechGenerator • Mode Indication bits
• Comfort Noise
• Tone EmulationΣ
(+)
(-)Filter
Codebook
Codebook Tone Emulation
• DTX IndicationΣ
PredictionIndex Perceptual
WeightingError
Analysis
VocoderOutput BitsMUX
Error
Benefits of Activity Detection:
1)
2)
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 dataTransmitter
Checksum011010
Original Data 100101101010
CRC Generator
Original Data 100101101010
Receiver
If Checksums do not match Received Data Received Checksum
RF Transmission Path
CRC Generator
Re-Generated Checksum011011
If Checksums do not match, there is an error
Received Data 100101001010
Received Checksum 011010
CRC Algorithms
• CRC Algorithms
3GPP TS 25.212¶ 4.2.1.1
g– 0, 8, 12, 16, or 24 parity bits (determined by upper layers)pp y )
g(CRC24) D24 + D23 + D6 + D5 + D + 1• g(CRC24) = D24 + D23 + D6 + D5 + D + 1
• g(CRC16) = D16 + D12 + D5 + 1
• g(CRC12) = D12 + D11 + D3 + D2 + D + 1
• g(CRC8) = D8 + D7 + D4 + D3 + D + 1g( )
FEC Coding: The Convolutional Coder
Convolution Coding
Transmitter
Original Data 00011011...
FECGenerator
FEC Encoded data 1010011100110110...
Transmitter
RF Transmission Path
Original Data 00011011
Viterbi Decoder
Receiver
FEC Coding: Convolutional Coder
• Convolutional Coding: ExampleConvolutional Coding: ExampleX2k
clock
D DInput Data 1010...
MUX Coder Output
clock
X2k+1
R = 1/2 , k=2 Convolutional Coder
• For every input bit, there are two output bits
• The maximum time delay is 2 clock cycles
FEC Coding RulesFEC Coding Rules• FEC Coding
3GPP TS 25.212¶ 4.2.3
Transport Channel Coding Method Coder Rate
BCH Convolutional Coding 1/2
PCH Convolutional Coding 1/2
RACH Convolutional Coding 1/2 RACH Convolutional Coding 1/2
No Coding
Convolutional Coding 1/2 or 1/3 DCH, DSCH, CPCH FACH CPCH, FACH
Turbo Coding 1/3
WCDMA Convolutional Code Generators3GPP TS 25.212¶ 4.2.3.1
DD D D D D D DDataIn
Rate 1/2, k=9 coder:
2:1MUX
DataOut
DD D D D D D DData
Rate 1/3 , k=9 coder:
In
3:13:1MUX
DataOut
WCDMA Turbo Code Generator
Xk3GPP TS 25.212¶ 4.2.3.2
D t I
Xk
Zk
Data InRate = X
MUX
Data Out3x input bits
Xk D D D
3x input bits + 12 Termination bits
TurboInterleaver
Z’k
D D D
X’k
At end of data block, both switches go “down” to provide 12‐bit Trellis Termination: [ x z x z x z x' z' x' z' x' z' ][ xK+1, zK+1, xK+2, zK+2, xK+3, zK+3, x K+1, z K+1, x K+2, z K+2, x K+3, z K+3 ]
Turbo Coding
T b C d• Turbo Codes
Outperform Convolution 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
DataDecodedData
D D
1
Turbo Encoder Turbo Decoder
Decoder #1
Encoder #1
MUX DE-MUXP1
P1
Interleaver
terlea
ver
nte
rlea
ver
Encoder #1
Encoder #2 Decoder #2P2 D
Interleaver
Int
De-
I
P2
Interleaving 1st level
Interleaving Matrix
Transmitter
Original Data Samples1 2 3 4 5 6 7 8 9 1 2 3
4 5 67 8 9
Interleaved Data Samples1 4 7 2 5 8 3 6 9
RF Transmission Path
Time
Am
plitu
de
De-Interleaving
Receiver
TimeTo Viterbi decoder
Interleaved Data Samples1 4 7 2 5 8 3 6 9
Errors Clustered
Interleaving Matrix
1 2 34 5 67 8 9
De-Interleaved Data Samples1 2 3 4 5 6 7 8 9
Errors Distributed
Interleaving 2nd level
I l i (‘K’ bl k i i (R C) bi h)• Interleaving (‘K’ blocks containing (R x C) bits each)
0, 1, 2, 3, ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ , (RC ‐ 1)Before Interleaving
0C••(R‐1)C
1C+1••(R‐1)(C+1)
‐ ‐ ‐‐ ‐ ‐
mC+m••(R‐1)(C+m)
C‐12C‐1••RC‐1
‐ ‐ ‐‐ ‐ ‐
Write Data into MatrixRow‐wise
C0 C1 Cm CC‐1‐ ‐ ‐ ‐ ‐ ‐Permute Matrix
Columns
0C••(R 1)C
mC+m••(R 1)(C )
1C+1••(R 1)(C 1)
C‐12C‐1••RC 1
Read Data from MatrixColumn‐wise
(R‐1)C (R‐1)(C+m) (R‐1)(C+1) RC‐1
C0 Cm C1 CF‐1
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‐1g
Rate Matching
• Rate Matching
– When coded data rates of services are incompatible, “Rate Matching” is used to equalize the data rates.
– Rate Matching may be performed by:
• Padding with extra bits
• Puncturing of bits using a pseudo‐random algorithmPuncturing of bits using a pseudo random algorithm
– For complete rate matching rules, see 3GPP TS25.212 ¶ 4.2.7
Rate matching
I/Q Modulation
• Graphical representation of an I/Q modulated signal Qsignal Q
( I = 1, Q = 1 )( I = -1, Q = 1 )
I
RF Carrier amplitude
RF Carrier phase angle
( I = -1, Q = -1 ) ( I = 1, Q = -1 )
1 Modulation Symbol represents 2 data bits
Modulation efficiency = 2 bits/symbol
I/Q Modulation
• I/Q (In‐phase/Quadrature) Modulation: Definition
Two data streams are multiplied by a common carrier frequency, but p y q y,at phase offsets of 0 degrees (cosine)and 90 degrees (sine)
Data Stream #1 “ I ”+1
90o
I sin (2 π fRF t)
+ Q cos (2 π fRF t)
+1
-1
SUM
cos ( 2 π fRF t)
Q ( RF )
Data Stream #2 “ Q ”+1
-1
I/Q Modulation
• By multiplying by the sin and cosine at the receiver, the original I and Q data streams are recovered
Data Stream #1 “ I ”+1
90oSUM
I sin (2 π fRF t)
+ Q cos (2 π fRF t)
LPF-1
SUM
cos (2 π fRF t)
D t St #2 “ Q ”
LPF
Data Stream #2 “ Q ”+1
-1
The WCDMA Transmitter
BS code (DL) or
UE code (UL)
Spread Spectrum Code
(Gold Code)“Scrambling
Code”
OVSF CodeGenerator
RF
FIRFilterComplex
Spreading
“ChannelizationCode”Data
Channel Code
Data 011010
1….
Add CRC Bits
Add FEC Bits
I/Q Mod.
Out
FIR
Inter-leaver
p g(DL)
HPSKSpreading
(UL)
S/P
FIRFilter
Error Detection
Error Correction
Orthogonal Coding
SSMA Spreading,
PAPRReduction
SpectralContainment
RF Modulation
FadingResistance
Summary voice coding
Traffic data (122x2)
Add CRC bits 244T il 8
CRC16
T il 896
96CRC 16
Add CRC bits
Layer 3 Control data244
Traffic @ 12.2 kbps L3 Data @ 2.4 kbps
Conv. Coding R=1/3
360
Add Tail bits
804
260
Tail 8
360
112
Tail 8
1st interleaving
Add Tail bits
Conv. Coding R=1/3
1st interleaving804
402
110 110 110 110Rate Matching
402Frame Segmentation
#1a 490 #2a 490 #1b 490 #2b 490
Frame Segmentation 90 90 90 90
6002nd interleaving 600 600 600
490 110
slot segmentation 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40
490 110 490 110 490 110
Radio frame FN=4N+1 Radio frame FN=4N+2 Radio frame FN=4N+3Radio frame FN=4N
slot segmentation
30 ksps DPDCH
40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40
600 bits (300 symbols) 600 bits (300 symbols) 600 bits (300 symbols) 600 bits (300 symbols)
Summary data coding
Traffic data (3840x2)
3840
CRC16
96
96CRC 16
Layer 3 Control data3840
Traffic @ 384 kbps L3 Data @ 2.4 kbps
3840
CRC16
3840
Add CRC bits Add CRC bits
Turbo Coding R=1/3
36023160
11568
7712
3840
Terminationbits
360
112
Tail 896
1st interleaving
Conv. Coding R=1/3
1st interleaving
3840
Concatenate Concatenate
Add CRC bits Add CRC bits
12 11568 12
360
9525
23160
11580
75 75 75 75Rate matching
1st interleaving
Frame Segmentation
1st interleaving
11580
9525 9525 9525
Frame Segmentation 90 90 90 90
9600
9525 75
2nd interleaving 9600 9600 9600
9525 75 9525 75 9525 75
slot segmentation 640 640 640 640 640 640 640 640 640 640 640 640
Radio frame FN=4N+1 Radio frame FN=4N+2 Radio frame FN=4N+3Radio frame FN=4N
slot segmentation
480 ksps DPDCH 9600 bits (4800 symb.) 9600 bits (4800 symb.) 9600 bits (4800 symb.) 9600 bits (4800 symb.)
640 640 640 640 640 640 640 640 640 640 640 640
Summary
S h i tiSynchronization
Acquisition and Synchronization
• Physical Layer Procedures1) UE Acquisition and Synchronization P-CCPCH1) UE Acquisition and Synchronization
Initiate Cell Synchronization
(PSC + SSC + BCH)
UE Monitors Primary SCH code, detects peak in matched filter output
Slot Synchronization Determined ------>
UE Monitors Secondary SCH code, detects SCG and frame start time offset
Frame Synchronization and Code Group Determined ------>
UE Determines Scrambling Code by correlating all possible codes in group
Scrambling Code Determined ------>
UE Monitors and decodes BCH data
Cell Synchronization Complete
Synchronization Codes
Synchronization Codes (PSC, SSC)
Broadcast by BS• First 256 chips of every SCH time slot
3GPP TS 25.213 ¶ 5.2.3
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”
Primary Synchronization Code
• Primary Synchronization Code (PSC)l t 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
3GPP TS 25.213 ¶ 5.2.3
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 >
Note: PSC is transmitted “Clear” (Without scrambling)
2304 Chips256 ChipsSCH BCH
Broadcast Data (18 bits)SSCi
pp
PSC
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1 Frame = 15 slots = 10 mSec
Slot Synchronization
• Slot Synchronization using Primary Synchronization Code
3GPP TS 25.214 Annex C
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)
P-CCPCH
(PSC)
MatchedFilterOutput
time
Secondary Synchronization Code Group
3GPP TS 25.213 ¶ 5.2.3
• 16 Fixed 256‐bit Codes; Codes arranged into one of 64 patterns
slot number Scrambling Code Group
#1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15
G 1 1 1 2 8 9 10 15 8 10 16 2 7 15 7 16
SSC1 SSC2
SSCi
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
• • •
SSC2 SSC3 SSC4 SSC5 SSC6 SSC1 SSC15• • •
• • •
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
SSC6 SSC7 SSC8 SSC9 SSC10
1 15
Group 64 9 12 10 15 13 14 9 14 15 11 11 13 12 16 10
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1 Frame = 15 slots = 10 mSec
SSC10 SSC11 SSC12 SSC13 SSC
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 Frame 15 slots 10 mSecSSC14 SSC15 SSC16
Frame Synchronization
• 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]
10 mSec Frame (15 slots x 666.666 uSec)
Matched Filter
Matched to SSC code group pattern
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]
code g oup patte
MatchedFilterOutput
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 SSCRemember, no cyclic shift of any SSC is equal to any other SSC
time
Call SetupCall Setup
PRACH procedure
Random Access
• Random Access Attempt and AICH Indication3GPP TS 25.211 ¶ 7.3
AICH
RACH
PPre-
bl
Pre-amble
RACH
message part
4096 chips(1.066 msec)
Pre-amble
amble
A
message part(UE Identification)UE
NoInd.
NoInd.
Acq.Ind.BS
Random Access Procedure
• Prior to initiating a Random Access attempt, the UE receives:
The preamble scrambling code for this cell
The available random access signatures and set of available RACH sub-channels
The available spreading factors for the message part
The message length (10 ms or 20 ms)
Initial preamble power parameter
The power-ramping factor Power Ramp Step [integer > 0]The power-ramping factor Power Ramp Step [integer > 0]
The parameter Preamble Retrans Max [integer > 0]
The AICH transmission timing parameter [0 or 1]
The power offset ΔPp-m between preamble and the message part.
Transport Format parameters
Random Access Preamble Signatures
Random Access Preamble Signature Symbols Signature P0 P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 P13 P14 P15
3GPP TS 25.213 ¶ 4.3.3.3
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 15 1 -1 -1 1 -1 1 1 -1 -1 1 1 -1 1 -1 -1 1
• Preamble codes are 16-long Orthogonal 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 Scrambling Codes
• Random Access Preamble Scrambling Codes
Preamble Scrambling Code is a 4096‐chip segment of a 225‐long Gold CodePreamble Scrambling Code is a 4096‐chip segment of a 2 ‐long Gold Code
The UE targets one BS by using the BS’s indicated preamble scrambling code
“All UE accessing this cell shall use Random Access Preamble Spreading Code
n2 ”
“All UE accessing this cell shall use Random Access Preamble Spreading Code
n1 ” n2n1
Random Access
• Physical Layer Procedures
2) UE Requests System Access and Registration P-CCPCH
(PSC + SSC + BCH)
Cell Synchronization Complete
UE Reads Random Access parameters from BS;Calculates Random Access probe power
Initiate Random Access Attempt; Respond to Authentication challenge
When system Registration is complete, UE enters Idle mode
Paging procedure
Paging procedure
Admission ControlAdmission Control
Admission Control
The most important − and the most difficult − to control in WCDMA is theinterference occurring in the radio path.
One of the basic criteria for planning is to define the acceptable interferenceOne of the basic criteria for planning is to define the acceptable interferencelevel, with which the network is expected to function correctly.
This planning based on the actual signals the UE transmit set practical limitsf th U i t f itfor the Uu interface capacity.
A value called SIR (Signal-to-Interference Ratio) is used in this context.
In the BTS receiver, the interference and the signal must have a certain levelof power difference in order to extract one signal (code) out from the othersignals using the same carrier.
Every UE having a bearer active through this cell “consumes” a part of theSIR. The cell is used up to its maximum level when the BTS receiver is notable to extract the signal from the carrier
The main task of admission control is to estimate whether a new call can haveaccess to the system without sacrificing the bearer requirements of existing calls.
The AC algorithm should predict the load of the cell if the new call isThe AC algorithm should predict the load of the cell if the new call isadmitted.
Based on the admission control, the Radio Network Controller(RNC) either grants or rejects the access.
When applying mathematics, it can be found out that the Signal-to-InterferenceRatio (SIR) or Interference Margin has direct relationship with the cell load If weRatio (SIR) or Interference Margin has direct relationship with the cell load. If weexpress the cell load with a Load_Factor (10 % load gives value 0.1) and markthe Interference Margin with I, it leads to the following equation:
⎟⎟⎠
⎞⎜⎜⎝
⎛−
⋅=FactorLoad
LogI_1
110
Admission Control
In te r fe re n c e M a rg in (d B ) a n d L o a d F a c to r
2 0
2 5(d
B)
5
1 0
1 5
2 0
erfe
renc
e M
argi
n (
00 0 .1 0 .2 0 .3 0 .4 0 .5 0 .6 0 .7 0 .8 0 .9 1
L o a d F a c to r
Inte
Based on the graph it is fairly easy to indicate that when the cell loadexceeds 70 %, the interference in that cell will be very difficult to control.
This is h the WCDMA radio net ork is normall dimensioned ithThis is why the WCDMA radio network is normally dimensioned withexpected capacity equivalent to Load Factor value 0.5 (50 %). This valuehas a safety margin in it and the network will behave as expected.
Admission Control Factors
Transmission
availability
Codes available
Node B
Processing Capabilities
Admission
Control
SoftPower
recourses
Soft handover & upgrades
Margins
Interference limitation
Cell breathing conceptCell breathing conceptCell breathing conceptCell breathing concept
C ll b thi i CDMA h d b th lti l i t f d d l th t d ff b t d itCell breathing is a CDMA phenomena caused by the multiple access interference, and models the trade-off between coverage and capacity
Desired Signal
InterferingSignals
Max TX powerMax TX power
Cell breathing conceptCell breathing conceptCell breathing conceptCell breathing concept
C ll b thi i CDMA h d b th lti l i t f d d l th t d ff b t d itCell breathing is a CDMA phenomena caused by the multiple access interference, and models the trade-off between coverage and capacity
Desired Signal
InterferingSignals
( f )( f ) b fb fNoise rise (interference margin) Noise rise (interference margin) αα number of usersnumber of users
H dHandover
WCDMA Handover Types
2 Categories of Handovers exist in WCDMA based on connection status
Soft Handover :(Make before Break)
H d H d (B k b f M k )Hard Handover: (Break before Make)
Each Category further divided into types depending on the action taken in the Handover commandin the Handover command
WCDMA Handover Types
Hard Handover : can by divided into three typesInter Frequency HandoverUE change WCDMA carrier frequencyUE change WCDMA carrier frequency
Inter Radio Access Technology Handover - (I-RAT) Handover -UE change WCDMA carrier to GSM network or vice versag
Inter Radio Access Technology Cell Change - (I-RAT) Cell Change -UE change WCDMA carrier to GPRS network or vice versa
In all Hard Handover types Traffic and control channels are disconnected thenIn all Hard Handover types Traffic and control channels are disconnected then reconnected – Break Before Make –
WCDMA Handover Types
Soft Handover : can by divided into two typesSoft Handover
UE connected to more than one RBSs at same time – Theoretically up to number of RAKE Receiver fingers, practically by Active set
Softer HandoverSofter HandoverUE connected to another cell within the same RBS
UE has the ability to add, remove and replace radio links for different cells on same radio frequencycells on same radio frequency
Continuous data flow is maintained as data is combined at RAKE receiver
Soft Handover degrade system capacity where UE is connected to more than RBS in same time
Soft Handover
BTSBTSBTS
Soft Handover
Frequencyf1
Frequencyf1
Soft Handover
Soft handover is performed between two cells belonging to different Node Bsbut not necessarily to the same RNC. The source and target cell of the softhandover has the same frequency.
CDMA Soft HandoverCDMA Soft Handover
Monitor Neighbor BS Pilots Add Destination BS Drop Originating BS
– One finger of the RAKE receiver is constantly scanning neighboring Pilot g y g g gChannels.
– 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
WCDMA Soft Handover
• Each cell uses a different Scrambling Code• Each cell has an independent time reference• CPICH and System Frame timing between cells is arbitrary
D ti ti BSDestination BSOriginating BS SC5 SC6
SC1SC4SC7 SC8 SC4SC7 SC8
WCDMA Handover Scenarios
Core Network
3GPP TS 25.832
RNS RNS
Iu Iu
RNC RNCIur
Iub IubIub Iub←UTRAN →
Node B Node B Node B Node B
Inter‐Node( d f )
Intra‐Node( f )
Inter‐RNS( f i h(Hard or Soft) (Softer)(Soft with Iur;Hard with no Iur)
The WCDMA Soft Handover Problem...
• WCDMA Base Stations have Asynchronous timing references• IS‐95/cdma2000 BS’s are synchronized to GPS!
Data 2TFCIData 1 TPC Pilot
0.666 msec DPCCH/DPDCH slot
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
10 msec DPCCH/DPDCH frame
CPICH 2CPICH 2CPICH 2
CPICH 1CPICH 1CPICH 1
CPICH 2
CPICH 1
10 msecframe
BS 1
BS 2DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH
DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH
Toffset
WCDMA Soft Handover
• Soft Handover Initiation
(2)UE measures
(3)UE Reports measurements
(1)UTRAN informs UE
(4)UTRAN decidesUE measures
CPICH power and time delay from adjacent cells
UE Reports measurements to UTRAN
UTRAN informs UE of neighboring cell information
UTRAN decides the handover strategy
BS 2
CPICH 2CPICH 2CPICH 2
CPICH 1CPICH 1CPICH 1
DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH
CPICH 2
CPICH 1
DPCCH/DPDCH
10 msecframe
BS 1
BS 2
DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH
ToffsetUE Reports Toffsetto UTRANto UTRAN
UTRAN
Softer Handover
BTSSector 1f1
Sector 2f1Multipath Signal
through Sector 1
Sector 3f1
through Sector 1
Multipath Signalthrough Sector 3
f1g
Softer Handover
In softer handover the UE transmits and receives signals via two air interfacechannel concurrently, one for each sector separately. Both channels are received aty, p ythe same Node B by maximal ratio combining RAKE processing.
WCDMA Soft Handover
S f H d E i(6)UE Rake Receiver Synchronizes to BS2
(7)UE in soft handover with BS1 and BS2
(5)UTRAN Commands BS2 to adjust DPCH timing by
(8)When BS2 sufficiently strong, drop BS1.
• Soft Handover Execution
DPCCH/DPDCH DPCCH/DPDCH’sToffset (Handover complete)
CPICH 2CPICH 2CPICH 2CPICH 2BS 2
CPICH 1CPICH 1CPICH 1
DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH
CPICH 1
DPCCH/DPDCH
10 msecframe
BS 1 DPCCH/DPDCHDPCCH/DPDCHDPCCH/DPDCH DPCCH/DPDCH
Toffset
ToffsetUE Reports Toffsetto UTRAN
UTRAN
UTRAN Commands BS2to adjust DPCH timingby Offset
RAKE Reception Concept
Interference in WCDMA plays greater rule than thermal noise
Multi paths reception for same signal can cause fading phenomenon
Delay between multi paths is typically 1-2 μSec in urban areas and 20 μSec in Hilly areas
WCDMA chip time is 0.26 μSec
WCDMA system uses RAKE receiver to overcome fading problem
Rake Reception Concept
Rake Receiver consists of number of reception fingers
Dedicated finger assigned to do measurements on NeighbourDedicated finger assigned to do measurements on Neighbour Node-Bs
Each finger locks on same signal but for different delays – different pathspaths –
Delay resolution within finger is ± ½ chip, total delay within receiver 30 μSec
The alignment of the fingers done by correlating the decoded CPICHwith an internally generated version at receiver. Applying suitable amount of delay at each finger
After Alignment a Combined signal will be generated – constructive addition –
The RAKE ReceiverThe RAKE Receiver
• 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 handoverAlso be used to track other base stations signal during soft handover– One finger used as a “Searcher” to identify other base stations
Finger #1
Finger #2
Sum ofindividual multipath components
Combinercomponents
Finger #N
Searcher Finger
Power measurement of Neighboring Base Stations
The RAKE Receiver ArchitectureThe RAKE Receiver Architecture
CDMA RAKE Receiver Architecture
“I” PN(2 f
CarrierFrequencyTrackingLoop Rake Receiver
“Finger”
BPF LPF
I PNCode(+1/-1)
ΣIntegrate
over‘SF’ chips
De-Interleave
Data
Viterbi/Turbo
Decoder
DecodedOutputBits
bit rate = chip rate / SF
cos(2πfIFt)
ΣDI/Q
Demod
“Q” PNCode
(+1/-1)
Orthogonal
Code(+1/-1)
p
CRCVerification
cos(2πfRFt)
Ti i
Dd
ErrorIndication
PilotOrthogonal
Code(all zeros)
TimingAdj. Correlator
Other Rake Receiver Finger
Hard/Inter‐Frequency Handover
BTSBTS
Hard Handover
Frequencyf1
Frequencyf2
Hard Handover
Hard Handover functionality is same like GSM
Inter‐System Handover
BTSBTS
WCDMA GSM900/1800
Inter-System Handover
Inter Radio Access Technology Handover ‐ (I‐RAT) Handover ‐UE change WCDMA carrier to GSM network or vice versa
Inter Radio Access Technology Cell Change ‐ (I‐RAT) Cell Change ‐UE change WCDMA carrier to GPRS network or vice versa
Handover Control (HC)
BTSBTSBTSSector 1
f1Sector 2
f1Multipath Signalthrough Sector 1
Soft
Frequencyf1
Frequencyf1
Sector 3f1
Multipath Signalthrough Sector 3
Soft Handover Softer HandoverBTSBTS
Inter-System HandoverBTSBTS
WCDMA GSM900/1800
HandoverBTS
Frequencyf1
Frequencyf2
Hardf1 f2
Inter‐Frequency Handover
• Inter‐frequency Handover
– To allow inter‐frequency measurements, data is compressed in time so that some of the 10 mSecframe is available for measurements.
• 8 to 14 slots per frame may be used
– Data compression can be accomplished by:
• Decreasing the Spreading Factor by 2:1 – Increases Data Rate so bits get through twice as fast!– Increases Data Rate so bits get through twice as fast!
• Puncturing bits– weakens FEC coding
• Higher layer scheduling– Reduces available timeslots for user traffic
Compressed Mode Operation3GPP TS 25.212 ¶ 4.4.3
• 1 to 7 slots per frame diverted for hard handover processesThe complete TFCI word must be transmitted every frame, even in Compressed Mode.Compressed Mode Slot formats (A,B) contain higher proportion of TFCI bits per slot compared with normal slots
1 2 3 4 5 6 7 8 9 1 1 1 1 1 11 2 3 4 51 1 1 1 1 6
10 mSec Frames (15 slots)
Normal Operation
per slot compared with normal slots.
1 2 3 4 5 6 7 8 9 10
11
12
13
14
151 2 3 4 51
112
13
14
15
6
Compressed‐Mode; single‐frame method
1 2 3 4 5 11
12
13
14
151 2 3 4 51
112
13
14
15
6
Transmission Gap
1 2 3 4 5 6 7 8 9 10
11
12
4 511
12
13
14
15
6
Compressed‐Mode; double‐frame method
Transmission Gap
Handover to/from GSM
• Handover to/from GSM
– GSM handover is an explicit requirement in WCDMA
F ilit t d b lit f lti f t t– Facilitated by commonality of multi‐frame structures
12 WCDMA 10 mSec Frames (120 ms)
1 2 3 4 5 6 7 8 9 10 11 12
T T T T T T T T T T T S T T T T T T T T T T T T T I
GSM 26‐frame TCH multiframe (120 ms)
T = Traffic FrameS = SACCH FrameI = Idle Frame
P C lPower Control
WCDMA Power Control Importance
Power is a shared resource in WCDMA system
Po er tili ation is so important toPower utilization is so important toIncrease system capacityDecrease overall interference in the system (Overcome near far problem effect)far problem effect)
WCDMA system provide fast power control procedure
1500 power order command / Sec = 1 power order command / Slot
3 Loops interact to provide power control procedure
WCDMA Power Control Importance
All WCDMA users operating on same carrier are sources for interference
Amount of interference of all users on a Channel provide the limit of system capacity on that channel
i.e.) each channel has its minimum accepted SIR (Signal to Interference Ratio)
Having UEs in a different position from Node-B also create the near- far problem,
i.e.) Near UEs – suffer from relatively low path loss - can block the decoded signal from far UEs
WCDMA Power Control Importance
UE C suffers less path loss the B and finally A
WCDMA Power Control Importance
All Mobiles A, B and C suffers same path lossMobile A decoded signal suffers relatively little interference
All Mobiles A, B and C suffers different path lossMobile A decoded signal blocked due high interference
WCDMA Power Control procedure
WCDMA power control procedure consists of 3 LoopsOpen-loopOuter-loop pInner-loop
Increase Transmit Power
by 1 dBOpen-Loop Power Control
Measure
Transmit Access Preamble
Access Acknowledged?
by 1 dBNoCompute
Initial Transmit
Power
received powerfrom BS
Read BS transmit power from Broadcast
ChannelYes
MS BeginsUplink TCH
Transmission
Outer-Loop (slow) Power Control Inner-Loop (fast) Power Control
BLER Acceptable
?
Raise RxPower Target
No Received power
> target?
Increase MS Transmit Power
by 1 dB
D MS
No
Transmission ?Lower Rx
Power TargetYes
> target? Decrease MS Transmit Power
by 1 dBYes
CDMA Power ControlCDMA Power Control
P(SIR‐Target,UL)
Inner loopInner loop
DL‐TPC UL‐TPC RNCUL‐Outer loop
P(SIR‐Target, DL)
SIR‐Target,UL
SIR‐Error,UL
Open loopBLER‐Measured,DL
DL‐Outer loop
BLER = Block Error Rate
SIR = Signal to Interference Ratio
TPC = Transmit Power Control
P(Startvalue)SIR‐Target,DL
Course OutlinesCourse Outlines
1. Before We Start
2. UMTS Introduction
4. UMTS Network Architecture.
3. WCDMA Concepts.
5. UMTS Air Interface Principles.
6. UMTS Procedures
7. UMTS services and applications
Topics
• Person‐to‐Person Circuit Switched ServicesPerson to Person Circuit Switched Services
• Person‐to‐Person Packet Switched Services
C S i• Content‐to‐Person Services
• Location Based Services
• Fixed Mobile Convergence
Person‐to‐Person Circuit Switched Services
• AMR Speech Service11.4 or 22.8 Kbps
(3.65 – 10.6 Kbps) (4.75 – 12.2 Kbps)
Error Control Bits Voice Bits
• Video Telephony
CircuitS i h dCircuit
S i h dSwitchedNetworkSwitchedNetwork
Packet SwitchedNetwork
AMR Speech Service : Introduction
• AMR provides a set of codec's fitting in FR and HR physical channels, providing variable tradeoff between error protection and speech quality,...
• And an algorithm to change between codec's (Link Adaptation, or Codec Mode Adaptation)Adaptation)
• An algorithm to change between FR and HR codec's (Channel Mode Adaptation)
20
25
bit/s
) Channel codingSpeech coding Error Protection (FER)
10
15
l bit-
rate
(kb
0
5
FR12.2
FR10.2
FR7.95
FR 7.4 FR 6.7 FR 5.9 FR5.15
FR4.75
HR7.95
HR 7.4 HR 6.7 HR 5.9 HR5.15
HR4.75
Cha
nne
Speech Quality (MOS)
AMR codec mode
Video Telephony
• constant bit rate, small delay variation and continuous bit flow
• Lower BER requirements comparing to speech servicesq p g p• Available for both circuit switched and packet switched
networks
CircuitSwitchedNetwork
CircuitSwitchedNetwork
Packet SwitchedNetwork
Person‐to‐Person Packet Switched Services
• Images and Multimedia
• Push‐to‐Talk over Cellular (PoC)
• Voice over IP (VoIP)
• Real Time Video Sharing (RTVS)Real Time Video Sharing (RTVS)
• Multiplayer Games
camera
file
Multimedia Messaging Service (1/2)
MultimediaMessagingService
music
SMS
SmartMessaging& EMS
video
textonly
Text, simple graphics,ringing tones
stills
etc.
Multimedia Messaging Service (2/2)
Standardised „envelope“: encapsulated messages
variable size
messages
Content:Minimum set of supported media types recommended:• text• audio• audio• images• video
addressesMSISDN or URL
Push‐to‐Talk over Cellular (PoC)
Telephone communication
• Communication the mainPush to Talk communication• Virtual connection exists throughout theCommunication the main
activity
• Capacity is used for the whole duration of the
Virtual connection exists throughout the session = possibility to talk at any instance, staying informed
• Capacity is used only when someone talks, one way
call, two wayy
• Near real‐time service
PoC is a Voice over IP serviceover a GPRS network
UMTS N t kUMTS NetworkIP Packets
IP Packets
IP PacketsIP Packets
IP PacketsIP Packets
IP Packets
IP PacketsIP Packets
IP PacketsIP Packets
IP PacketsIP Packets
Client 2
Client 1POC application servers• PoC Call Processor
PoC Register
Client 3
• PoC Register
Voice over IP (VoIP)
• Provide rich call (real time communication session between two or more persons)session between two or more persons)
• Complement with 2‐way video, streaming video, images, content sharing, gaming etc.
Multiplayer Games
Content‐to‐person Services
• Browsing
• Audio and Video Streaming
• Content Download
Browsing
Audio and Video Streaming
Streaming FeaturesStreaming Features– Supports both audio and video streaming
– Supports VCR‐like controls, namely PLAY, PAUSE & STOP
Pl /P /R t i hil l i– Play/Pause/Resume streaming while playing
– Stop streaming midway
– Abort streaming session
IP Multimedia Services (IMS)
• Enable the usage of multimedia services built on Internet applications and protocolson Internet applications and protocols
• Enable IP connectivity between users
Utili S i I iti ti P t l (SIP) t• Utilize Session Initiation Protocol (SIP) to establish peer‐to‐peer sessions
Location based services
L ti b d i t d i
BTSGMLC
RNC
HLR3G-SGSN
• Location can be used in smart devices(for example in a car).
BTS
3G-MSC
Location Server
ApplicationsBSC
SMLC
• There are different ways to locate a
BTS
Location ManagementToolNetwork Management
/Planning System
• There are different ways to locate a subscriber. The most common will use BTS measurements.
• Location based information can be used for different applications.
Location services ‐Methods
• Cell ID based methodP iti i ith th h l f th i b t ti– Positioning with the help of the serving base station
• GPS ‐ Global Positioning System– Accurate but limitations indoors and during bad weather conditions– Accurate, but limitations indoors and during bad weather conditions
– Terminals may be equipped with GPS receivers.
Location Based Service examples