CW-1© Copyright Roshdy H.M. Hafez 1996-2000
3G Wireless
Third GenerationThird GenerationWirelessWirelessSystemsSystems
CW-2© Copyright Roshdy H.M. Hafez 1996-2000
About the Instructor
Dr. Roshdy H.M. HafezDr. Roshdy H.M. Hafez
email: email: hafezhafez@@scesce..carletoncarleton.ca .ca
CW-3© Copyright Roshdy H.M. Hafez 1996-2000
3G Wireless
4Motivation for 3G4IMT-2000 Development Procedure4Cdma20004UTRA/ARIB WCDMA4UWC-13643G Networks
Course Outline
CW-4© Copyright Roshdy H.M. Hafez 1996-2000
Motivation for 3G
§ The second generation (2G) wireless systems
§ Motivations and drives for new standards
§ The business case for 3G
§ The case for broadband fixed wireless access
CW-5© Copyright Roshdy H.M. Hafez 1996-2000
Second Generation Systems (2G)
Cell Size
Data Rate
Outdoor
indoor
CellularPCS
WirelessLAN
10 kbps
10 Mbps
l GSMl IS-136 (D-AMPS)l IS-95 (CDMA)
l Hiper LANl Ad-Hoc Networksl AT&Tl Olivettil IEEE802.11l … etc ..
CW-6© Copyright Roshdy H.M. Hafez 1996-2000
2G Services
Voice – Required in all
wireless environment– Huge market
Data – Limited data
applications– Circuit-switched– Short Message
Systems (SMS)– The main drive for 3G
100 - 200%Coding
BER =0.1%
OrFER= 1%
Performance
20-ms frames
8 – 13 kbps
Format
Vocoder rate
CW-7© Copyright Roshdy H.M. Hafez 1996-2000
2G Technologies
56 - 807150# / cell / 5 MHz
One cell7 cell4 cellsFrequency Re-use
BW / user ∼ 90 – 62.5 kHz10 kHz25 kHz
∼ 14 - 2038users/carrier
200 kHz
GSM
TDMA
30kHz
IS-136 IS-95
1,250 MHzBW / carrier
CDMA
CW-8© Copyright Roshdy H.M. Hafez 1996-2000
2G Network Model
HLR
MobileStations
Base Stations &B.S. Controllers
Network Mgmt Subscriber Services
OMC
AuC
BSC
MSC
BS
VLR
EIR
PSTN
ISDNVLR = Visitor Location
Registry
HLR = Home Location Registry
EIR = Equipment Identification Registry
AuthenticationCenter
MSC = Mobile Switching Center
BS = Base Station OMC = Operation & Maintenance Center
BSC = Base Station Controller
CW-9© Copyright Roshdy H.M. Hafez 1996-2000
2G Network Model (cont.)
BSC
BSC
MSC
IWF PacketOr IP-Network
PSTN
modem
CW-10© Copyright Roshdy H.M. Hafez 1996-2000
Example of 2G Data Connection
BSC
MSUE
RLP Protocol
PPP Protocol
RS-232
MSC IWF
HDLC FR
Application
DataNet.
CW-11© Copyright Roshdy H.M. Hafez 1996-2000
Example of 2G Voice Connection
BSC MSC
PSTN
BSC MSC
System A
System B
CW-12© Copyright Roshdy H.M. Hafez 1996-2000
2G to 3G Evolution
MultimediaPCS
PCS
Cellular
BroadbandMultimediaWireless
3GIMT-20002.5 G
2ndGeneration
CW-13© Copyright Roshdy H.M. Hafez 1996-2000
2G to 3G Evolution (cont.)
2G 3G
IS-95 IS-95-B Cdma2000
WCDMA
WCDMATDD
UWC-136
GSM
IS-136
IS-136+
EDGE 136HS
CW-14© Copyright Roshdy H.M. Hafez 1996-2000
2G Limitations
● Designed primarily for mobile telephony§ Symmetric communications§ Circuit-switched§ Tolerate high error rates (up to 0.1%)§ Narrowband information (< 14.4 kbps)
● Too Many Standards§ Several incompatible air interfaces (GSM, TDMA.
CDMA, AMPS, DECT,…) § Wireless LANs and PCS are totally different and
incompatible
● Isolated Networks§ Two different networks: IS-41-C and GSM-MAP§ No direct communications between different
operators
CW-15© Copyright Roshdy H.M. Hafez 1996-2000
Goals of 3G
l Wide range of operating wireless environmentsn Indoor / Outdoor
n High mobility (vehicular) / low mobility
l Wide range of transmission ratesn 1.2 kbps - 2 Mbps
l Support for different transmission modesn Circuit switched voice and datan IP-based application
l Support for a wide range of servicesl Multimedia QoS control capabilitiesl Compatibility and inter-operability with 2G systemsl Network interface standards
CW-16© Copyright Roshdy H.M. Hafez 1996-2000
The Business Case for 3G
● Viable Applications§ E-Commerce§ email§ Internet browsing§ Entertainment
● Consumer Acceptance§ Ease of use§ Consumer dependency on Internet§ Widespread acceptance of cellular technologies
● Efficient Distribution§ Integration with other devices§ New car built-in options
CW-17© Copyright Roshdy H.M. Hafez 1996-2000
The Business Case for 3G
CorporateApplications
Data Services & Information
DatabasesWWW
browsing
Always-ONPre-paid
Wide-spread availability
Time
CW-18© Copyright Roshdy H.M. Hafez 1996-2000
The Business Case for 3G (cont.)
50
100
150
200
250
300
350
1995 2000 2005 2010 2015
10%
20%
30%
40%
50%
60%
70%Million Subscribers Multimedia Penetration
among mobile users
CW-19© Copyright Roshdy H.M. Hafez 1996-2000
How About Fixed Wireless Access
● Mobility§ The term "Personal" implies "Mobility"§ Mobility management and Signaling
● Physical Limitations§ Personal communication is more
challenging§ PCS antennas cannot be easily optimized§ PCS environment is highly variable
● Radio coverage§ FWA requires targeted radio coverage§ PCS requires total coverage
● Market§ PCS has much bigger market§ Billions of potential subscribers
PCS vs. FWA
CW-20© Copyright Roshdy H.M. Hafez 1996-2000
The Business Case for FWA
● Viable alternative to cable, direct-to-home satellite and xDSL access over copper
● Easy to deploy with minimum infra-structure
● Very attractive solution for building-to-building high speed data links
CW-21© Copyright Roshdy H.M. Hafez 1996-2000
IMT-2000 Development Process
§ History of IMT-2000 within the ITU
§ The IMT-2000 guidelines
§ The RTT proposals and technical evaluations
§ The harmonization efforts 3GPP and GHG
CW-22© Copyright Roshdy H.M. Hafez 1996-2000
The Roots of IMT-2000
§ IMT-2000 = 3G
Race I
Race II
ACT
WRC 92
FPLMTS
IMT-2000
UMTS
1997
CW-23© Copyright Roshdy H.M. Hafez 1996-2000
What is IMT-2000?
§ A process to establish "Global Standards" for wireless communications
§ The IMT-2000 process addresses:
Ø Air Interface
Ø Networks
Ø Services
§ It covers
Ø Personal wireless (PCS)
Ø Fixed Wireless Access (FWA)
Ø Satellite
IMT-2000
AirInterface
Networks Services
PCS FWA Satellite
CW-24© Copyright Roshdy H.M. Hafez 1996-2000
IMT-2000 Data Model
CELLULAR
CORDLESS
IMT-2000
WLAN
Wired100.0
10.0
1.0
0.1
0.01
indoor outdoor
room building stationary walking car
Bit
rat
e M
b/s
CW-25© Copyright Roshdy H.M. Hafez 1996-2000
The IMT-2000 Three Environments
Cell Size
Data Rateindoor
WirelessLAN
144 kbps
10 Mbps
2 Mbps
3G
384 kbps
Outdoor
PCS/CellularVehicular
Pedestrian
Indoor
CW-26© Copyright Roshdy H.M. Hafez 1996-2000
Developing Air Interface Standards
Request for candidate RTT
proposals
Development of RTT Proposals
Self evaluation &Consensus building
Proposals & Evaluation reportsExamining proposed
RTT
RTT Synthesis & Consensus building
Recommendation
Implementation
VariousGroups
ITU
3GPP3GPP-2
1997
1998
1999
2000
CW-27© Copyright Roshdy H.M. Hafez 1996-2000
Developing Air Interface Standards
l There are 15 proposals submitted to ITU:
u 1 (indoor only)u 9 (indoor/outdoor)u 5 (satellite)
l Out of the 9 indoor/outdoor proposals
u 1 TDMAu 1 Hybrid TDMA/CDMAu 7 CDMA
l The best known proposals were
u Cdma2000 North American based on IS-95
u W-CDMA UTRA/ARIB Japan
u UWC-136 GSM & IS-136
CW-28© Copyright Roshdy H.M. Hafez 1996-2000
Harmonization
§ Global Partnerships:
Ø 3GPP (3G Partnership Project)
Ø 3GPP2
Ø UWCC (Universal Wireless Communications Consortium)
Ø OHG (Operators Harmonization Group)
§ Convergence of the technology
§ Emergence of technology groupings
CW-29© Copyright Roshdy H.M. Hafez 1996-2000
3G Partnership Project (3GPP)
ITU
High Level Frame Work
3GPP
Project Coordination Group
Technical Specification Groups
PartnersOrganizations
Regulators
Marketing
Individual Members
TechnicalContributions
International Recommendations
Technical Specifications
CW-30© Copyright Roshdy H.M. Hafez 1996-2000
3GPP
3GPP
Technical Specification Group
TSG-RAN
RadioAccessNetwork
TSG-SA
Servicesand
SystemsAspects
TSG-T
Terminal
TSG-CN
CoreNetwork
CW-31© Copyright Roshdy H.M. Hafez 1996-2000
3GPP2
3GPP2
Steering Committee
TSG-A
A-Interface
TSG-C
cdma2000
TSG-P
PacketData
Network
TSG-R
NetworkInterface
IS-41
TSG-S
Serviceand
SystemAspect
TSG-N
ANSI-41WIN
CW-32© Copyright Roshdy H.M. Hafez 1996-2000
Partnership Supporting Organizations
ITU - IMT-2000
3GPP
-ETSI-ARIB-Korea TTA-China CWTS
WCDMA Cdma2000
3GPP2
-TIA-ARIB-Korea TTA-China CWTS
UWC-136
-ETSI-US TR45.3-UWCC
DECT+
ETSI
CW-33© Copyright Roshdy H.M. Hafez 1996-2000
ITU Air-Interface Recommendation
CW-34© Copyright Roshdy H.M. Hafez 1996-2000
Cdma2000
§ Description of CDMA2000 physical layer
§ Data rates and signal processing blocks
§ Various deployment strategies
§ CDMA2000 MAC and LAC layers
§ Radio resource management
§ IP-based networking
CW-35© Copyright Roshdy H.M. Hafez 1996-2000
Origin of Cdma2000
§ Cdma2000 is an evolution of the 2G CDMA standard IS-95
IS-95-A IS-95-B RTT-1X RTT-3X
CDMA2000
TIA/EIA-95-BEnhanced CDMA
2G CDMACell Phones
CW-36© Copyright Roshdy H.M. Hafez 1996-2000
Cdma2000 Layered Architecture
CW-37© Copyright Roshdy H.M. Hafez 1996-2000
Cdma2000 Layered Architecture (cont.)
LAC / MAC
Signaling
Logical Channels
Physical Channels
Configurationrecords
Broadcast Common Dedicated
ProprietyAlgorithms
CW-38© Copyright Roshdy H.M. Hafez 1996-2000
RLP & QoS
§ Data applications are subjected to two processes:
Ø Radio Link Protocol (RLP):1. Transparent (no retransmission)2. Non-Transparent (with ARQ)
Ø QoS Control• Power allocation and Signal Format• Multiplex options• Priority enforcement• Congestion control
CW-39© Copyright Roshdy H.M. Hafez 1996-2000
Traffic Channels and Data Rates
TIA/EIA/95-A TCH 14.4 kbps
TIA/EIA/95-B F-CH
Up to 7 Supp. Ch.
115.2 kbps
IS-2000-1X F-CH
Up to 2 Supp. Ch.
DCCH 307.2 kbps
IS-2000-3X F-CH
Up to 2 Supp. Ch.
DCCH 10368 kbps
Max. RateDedicated ChannelsModes
Cdma2000
CW-40© Copyright Roshdy H.M. Hafez 1996-2000
Traffic Channels and Data Rates
4 RF Bandwidth = 1.25 MHz
4 Chip rate = 1.2288 Mcps
The IS-95-B Channel
OR
RTT-1X Channel
Multi-Carrier: RTT-NX
N=3, 6, 9, 12
4 Multiples of RTT-1X channels
4 RF Bandwidth = (N+1)*1.25 MHz
4 Chip rate = N*1.2288 Mcps
1.25 MHz 1.25 MHz 1.25 MHz 1.25 MHz
5 MHz
1.2288 Mcps 1.2288 Mcps 1.2288 Mcps
CW-41© Copyright Roshdy H.M. Hafez 1996-2000
Deployment Options
1.25 MHz
5 MHz5 MHz
1.25 MHz1.25 MHz
1.25 MHz
80 MHz
Mobile Tx Mobile Rx
95-B
RTT-1X
RTT-3X
CW-42© Copyright Roshdy H.M. Hafez 1996-2000
2G / 3G Compatibility
Carrier 1
95B or 1X
Carrier 1
Carrier 2
Carrier 3
MUX
Cdma2000-3X
5 MHz
3.6864 Mcps
1.25 MHz 1.25 MHz 1.25 MHz 1.25 MHz
5 MHz
1.2288 Mcps 1.2288 Mcps 1.2288 Mcps
D-MUX
Carrier 3
IS-95 N=1
Cdma2000x3
Carrier 2
Carrier 1
1.2288 Mcps
1.25 MHz
1.2288 Mcps
1.25 MHz
CW-43© Copyright Roshdy H.M. Hafez 1996-2000
Composite CDMA Waveform
1.25 MHz
Different
codes
Frequency
Time
20 ms frame
5 ms frame
CW-44© Copyright Roshdy H.M. Hafez 1996-2000
§ A physical resource is a Coded channel transmitted at a given level of Power for a certain time length "Frame"
§ Cdma2000 physical frame lengths [5 10 20 ms]
§ Tight power control:
Ø Open loop power controlØ Forward and Reverse closed loop power controlØ Outer loop power control
§ 9 Forward and 6 Reverse Radio Configurations
§ Many Channel Formats in every radio configuration
Major Characteristics
CW-45© Copyright Roshdy H.M. Hafez 1996-2000
Downlink Radio Configurations
20 ms
5 ms
20 ms
5 ms
5, 20 ms
5, 20 ms
5, 20 ms
5, 20 ms
5, 20 ms
20 ms
20 ms
Frame
1/2
1/3
1/4
1/3
1/3
1/6
1/4
1/2
1/4
1/2
1/2
Rate
1.8/3.6/7.2/14.4/28.8/57.6/115.2/
230.4/460.8/1036.89
1.8/3.6/7.2/14.4/28.8/57.6/115.2/
230.4/460.88
1.5/2.7/4.8/9.6/19.2/38.4/76.8/
153.6/307.2/614.47
1.5/2.7/4.8/9.6/19.2/38.4/76.8/153.6/307.26
3X
1.8/3.6/7.2/14.4/28.8/57.6/115.2/230.45
1.5/2.7/4.8/9.6/19.2/38.4/76.8/153.6/307.24
1.5/2.7/4.8/9.6/19.2/38.4/76.8/153.63
1X
1.8/3.6/7.2/14.42
1.2/2.4/4.8/9.6195B
Data Rate, kbpsRC
CW-46© Copyright Roshdy H.M. Hafez 1996-2000
Uplink Radio Configurations
5, 20 ms
5, 20 ms
5, 20 ms
5, 20 ms
20 ms
20 ms
Frame
1/4
1/2
1/4
1/3
1/4
1/4
1/2
1/2
1/3
Rate
1.8/3.6/7.2/14.4/28.8/57.6/115.2/230.4/460.8
OR
1036.8
6
1.2/1.35/1.5/2.4/2.7/4.8/9.6/19.2/38.4/76.8/153.6
OR
307.2/614.4
5
3X
1.8/3.6/7.2/14.4/28.8/57.6/115.2/230.44
1.2/1.35/1.5/2.4/2.7/4.8/9.6/19.2/38.4/76.8/153.6
OR
307.2
3
1X
1.8/3.6/7.2/14.42
1.2/2.4/4.8/9.6195B
Data Rate, kbpsRC
CW-47© Copyright Roshdy H.M. Hafez 1996-2000
Forward Physical Channels
Common Dedicated
Common PilotCommon Transmit Diversity Pilot
Auxiliary PilotAuxiliary Transmit Diversity Pilot
SynchPaging
Quick PagingCommon Control
Common Power ControlCommon Assignment
Broadcast Channels
FundamentalSupplementalDedicated ControlDedicated Auxiliary Pilot
CW-48© Copyright Roshdy H.M. Hafez 1996-2000
Reverse Physical Channels
Common Dedicated
AccessEnhanced AccessCommon Control
FundamentalSupplementalDedicated ControlPilotPower Control
Random Access Mode Circuit-Switched Mode
CW-49© Copyright Roshdy H.M. Hafez 1996-2000
Processing the Physical Channels
CodingRepeat
PunctureInterleave
Decimator
MaskedLong Code
MUX
Bitselector
I/Q &Binary
toBipolarMap
WkComplex
PNSpreading
Filter
Filter
Cos ωt
Sin ωt
Data
QPSKModulat ionPN Cell
Identification
WalshChannelization
Power controlSub-channel
Scrambl ing(privacy)
Errorcontrol
Cdma2000-1X
CW-50© Copyright Roshdy H.M. Hafez 1996-2000
Processing the Physical Channels (cont.)
CodingRepeat
PunctureInterleave
Decimator
MaskedLong Code
Bitselector
MUX
I/Q &Binary
toBipolarMap
W k1Complex
PNSpreading
Filter
Filter
Cos ω 1 t
Sin ω 1 t
Data
I/Q &Binary
toBipolarMap
W k2Complex
PNSpreading
Filter
Filter
Cos ω 2 t
Sin ω 2 t
I/Q &Binary
toBipolarMap
W k3Complex
PNSpreading
Filter
Filter
Cos ω 3 t
Sin ω 3 t
De
-Mul
tiple
xMUX
MUX
PowerControl
bits
+
CW-51© Copyright Roshdy H.M. Hafez 1996-2000
Channelization Using Walsh Codes
]0[0 =A
=
=
10
00
00
001
AA
AAA
=
=
01
11
10
0010
00
10
00
11
112
AA
AAA
=+
mm
mmm
AA
AAA 1
General Form
CW-52© Copyright Roshdy H.M. Hafez 1996-2000
The Pilot Channel [PN Cell Identifications]
• Transmitted at al l t imes on every CDMA carrier
• New mobiles use it to synchronize
• Receiving mobiles use it for channel estimation and RAKE combining
• Mobiles use it to detect new cells and request hand-off
• Each cel l has a unique pilot offsetthat identifies it.
CW-53© Copyright Roshdy H.M. Hafez 1996-2000
The Pilot Channel [PN Cell Identifications]
Inserted zero
.. 0 0 0 1 …000 0 1
14 zeros
Zeroshift
1 2 3 511
Ts
215=32768 chips
32767 chips
CW-54© Copyright Roshdy H.M. Hafez 1996-2000
Pilot in Different Cdma2000 Modes
1.2288 Mcps
1.25 MHz
1.25 MHz 1.25 MHz 1.25 MHz 1.25 MHz
5 MHz
1.2288 Mcps 1.2288 Mcps 1.2288 Mcps
5, 10 or 15 MHz
Nx1.2288 Mcps
Zeroshift
1 2 511
Ts
Zeroshift
1 2 511
N code cycles
Direct Spread
3X Multi-Carrier
95 or 1X
In MC, the pi lot is transmitted on every carrier with the same shift
512 shifts over N cycles
CW-55© Copyright Roshdy H.M. Hafez 1996-2000
The Long Code
◆ The output is a shifted version of the long code.
◆ The shift is uniquely related to the 42-bit mask
◆ Each mobile unit has its own unique mask (Electronic Identification)
◆ Some masks are common for access and other signaling
1234142
MOD-2 ADDER
THE REFERENCE LONG CODE GENERATOR
42-B
IT M
AS
K
OUTPUT
CW-56© Copyright Roshdy H.M. Hafez 1996-2000
Aligning the Long and Short Codes
● Absolute time reference is achieved by observing the states of the long and short codes
1
1
11 0 [15]
1 0 [15]
1 0 [41]
January 6, 1980
Zero offset I pilot
Zero offset Q pilot
Long code mask
26.66.. µs
approx. 41.425 days
1
1
11 0 [15]
1 0 [15]
1 0 [41]
approx. 37 centuries
● All base stations are synchronized through the GPS ● Time shifts of the I&Q pilot codes (short codes) identify
base stations● Time shifts of the long code identify individual users
CW-57© Copyright Roshdy H.M. Hafez 1996-2000
Air Interface Features & Facilities
§ Signaling formats
Eb/No ßà FER (BER)
Convolutionor Turbocoding
SymbolRepeat
SymbolPuncture
BlockInterleaver
Qualityindicator
Trailbits
§ Auxiliary pilots
CW-58© Copyright Roshdy H.M. Hafez 1996-2000
Air Interface Features & Facilities (cont.)
§ Different Frame Lengths
5 ms Efficient MAC signaling
For possible harmonization with WCDMA10 ms
20 ms Vocoders (IS-95 native)
20, 40 or 80 ms
[Logical] For efficient transmission of supplemental channels
§ Using the supplemental channels in burst format
Allocate-Lock-unlock approach
CW-59© Copyright Roshdy H.M. Hafez 1996-2000
Air Interface Features & Facilities (cont.)
§ RCCCH & the Enhanced Access ChannelØ Quick re-connectØ Slotted modeØ Reservation mode
Reverse Access Transmission
Reverse Pilot
AccessPreamble
AccessMessages
Pilot
Multiples of1.25 ms
Access Probe
CW-60© Copyright Roshdy H.M. Hafez 1996-2000
Air Interface Features & Facilities (cont.)
§ Common Assignment Channel
Designed for fast assignment in a random access packet mode.
§ Reservation
CW-61© Copyright Roshdy H.M. Hafez 1996-2000
Air Interface Features & Facilities (cont.)
◆ Carries PC bits for several reverse common control and enhanced access channels
MUX
0
N-1
RepeatSignal
MappingGain
MUX
N
2N-1
RepeatSignal
MappingGain
decimator MaskLong code
Generator @3.6864 Mcps
offset
48200 bps
12800 bps
24400 bps
NUpdate rate
§ Common Power Control Channel
CW-62© Copyright Roshdy H.M. Hafez 1996-2000
Quick Paging Channel
20 ms 80 msPCH slot
80 msQPCH s lot
Indicators for this slot
CW-63© Copyright Roshdy H.M. Hafez 1996-2000
Orthogonal Transmit Mode
BasebandFilter
Pha
se r
otat
ion
Repeat++
Repeat++
Σ
Σ
+
-
-
+
Cosωt
BasebandFilter
sinωt
Σ
BasebandFilter
Pha
se r
otat
ion
Repeat++
Repeat++
Σ
Σ
+
-
-
+
Cosωt
BasebandFilter
sinωt
Σ
PN I
PNQ
S1(t)
S2(t)
Walsh
QOF +/-
Walsh
QOF +/-
CW-64© Copyright Roshdy H.M. Hafez 1996-2000
Reverse Link Spreading & Multiplexing
ComplexPN
Spreading
Gain
Gain
Cos ωt
Sin ωt
Filter
Filter
Long code
PN I PNQ
[+ - - +]
[++ + + - - - -]
Gain
Gain
[+ -] 0r [+ - - +]
Gain
Gain
[+ + - -]
Pilot & PC bits
R-DCCH
R-SCH
second
R-SCHfirst
R-FCH
CW-65© Copyright Roshdy H.M. Hafez 1996-2000
Radio Resource Management Issues
§ Call admission?§ Assessment of available resources§ Predicting the impact of admitting new users§ Accounting for soft hand-off§ Estimating the feasible data rate
§ Optimum allocation of resources§ Power§ Code/Interleave/Repeat/Puncture Format§ Spot beams
§ Managing traffic fluctuations§ Feasible bandwidth on demand§ Avoiding tying up radio resources§ Quick re-connect
CW-66© Copyright Roshdy H.M. Hafez 1996-2000
UTRA/ARIB WCDMA
§ Description of the physical layer
§ Logical, transport and physical channels
§ Multiplexing and radio resource management
§ Synchronization and system acquisition
§ New features to improve signal detection
§ The MAC and LAC layers
§ The TDD and Asymmetric communications
CW-67© Copyright Roshdy H.M. Hafez 1996-2000
What is WCDMA ?
§ WCDMA is a wideband CDMA access system
§ There are several versions of WCDMA developed separately by ARIB (Japan), UTRA (Europe), Korea and NA.
§ All these proposals were harmonized earlier and now are presented as WCDMA
§ WCDMA has two modes:
Ø Frequency Division Duplexing (FDD)
Ø Time Division Duplexing (TDD)
§ WCDMA is strongly sponsored by the UMTS forum
CW-68© Copyright Roshdy H.M. Hafez 1996-2000
WCDMA Layered Protocol
Network Layer
Link Access Control (LAC)
Media Access Control (MAC)
Physical LayerTransportChannels
PhysicalChannels
LogicalChannels
What is being transmitted
How will it be transmitted
Coding, interleaving, multiplexing..etc.
Physical data stream
One transport channel Could be transmitted on
several physical channels
Protocol Layers
CW-69© Copyright Roshdy H.M. Hafez 1996-2000
Transport Channels
Up Link Transport Channels
Mobile
Dedicated Channel
Base
Dedicated Channel
Forward Access Channel
Broadcast Access Channel
Paging Access Channel
Random Access Channel
Common Packet Channel
Downlink Shared Channel
Down Link Transport Channels
Common
Dedicated
CW-70© Copyright Roshdy H.M. Hafez 1996-2000
Processing the Transport Channels
CodingStatic Rate Matching
OptionalFrame-to-
FrameInterleaving
TC
Mul
tiple
x
In-FrameInterleaver Down Link
ToPhysicalFrames
CodingStatic Rate
Matching
OptionalFrame-to-
FrameInterleaving
TC
Multiplex
In-FrameInterleaver
Dynamic Rate
Matching
Up Link
ToPhysicalFrames
CW-71© Copyright Roshdy H.M. Hafez 1996-2000
Flexible Transport to Physical Mapping
TC
De
-Mul
tiple
x
Map
per
TC
Mul
tiple
x
Map
per
One High Data Rate Transport
Channel
Transmitted on several
Physical channels
Several Low Data Rate Transport Channel
Transmitted on One Physical
channel
Transport Physical
CW-72© Copyright Roshdy H.M. Hafez 1996-2000
Mapping Transport to Physical Channels
Downlink
Map
Map
Dedicated Channel
Forward Access Channel
Broadcast Access Channel
Paging Access Channel
Downlink Shared Channel
Dedicated Physical Channel
Synchronization Channel
Common Pilot Channel
Common Control Physical Channel
Physical Downlink Shared Channel
Acquisition Indication Channel
Paging Indication Channel
Dedicated Channel
Random Access Channel
Common Packet ChannelDedicated Physical Control Channel
Physical Random Access Channel
Dedicated Physical Data Channel
Physical Common Packet Channel Uplink
CW-73© Copyright Roshdy H.M. Hafez 1996-2000
Highlights of Downlink Physical Channels
Indicates to the mobile that it has a paging message
PICHPaging Indication Ch.
Signals the mobile to transmit on common uplink channels
AICHAcquisition Indication Ch.
Common packet channelPDSCHPhysical Downlink Shared Ch.
Carries system information broadcast
CCPCHCommon Control Physical Ch.
Allows the mobile to search the cell and synchronize
SCHSynchronization Ch.
Facilitates the coherent detection mode
Carries user information
CPICHCommon Pilot Ch.
DPCHDedicated Physical Ch.
CW-74© Copyright Roshdy H.M. Hafez 1996-2000
Highlights of Uplink Physical Channels
Carries user's packet dataPCPCHPhysical Common Packet Ch.
Carries control signalsDPCCHDedicated Physical Control Ch.
Slotted ALOHA acess
Carries user information
PRACHPhysical Random Access Ch.
DPDCHDedicated Physical Data Ch.
CW-75© Copyright Roshdy H.M. Hafez 1996-2000
What is A Physical Channel?
§ A WCDMA physical channel is a coded stream of symbols transmitted within one slot in a frame.
§ All the slots of a given frame have the same channelization code but may carry different Transport Format
§ The transport format of each slot is signaled within the slot
TPC TFI Data
Time Slot
TFI = Transport Format IndicatorTPC = Transport Power Control
CW-76© Copyright Roshdy H.M. Hafez 1996-2000
WCDMA Frame Structure
Frame 1 Frame 2 Frame i Frame 72
Super Frame = 720 ms
Slot 1 Slot 2 Slot k Slot 15
Frame = 10 ms
Symbol
Chip0.26 µs
For 5 MHz BW
Slot = 0.666… ms
CW-77© Copyright Roshdy H.M. Hafez 1996-2000
Physical Layer Characteristics
1. Minimum Bandwidth
Ø 5 MHZ à TDD
Ø 2x5 MHz à FDD
Mobile Tx and Rx
Mobile RxMobile Tx
Frequency
Frequency
80 MHz 5 MHz
5 MHz
TDD
FDD
CW-78© Copyright Roshdy H.M. Hafez 1996-2000
Physical Layer Characteristics (cont.)
2. Chip rate is fixed at:
Ø 5 MHz à 3.84 Mcps
Ø 10 MHz à 7.68 Mcps
Ø 20 MHz à 11.52 Mcps
3. WCDMA uses a "Variable Processing Gain" approach. The chip rate is fixed while the data rate is variable.
4. Minimum processing gain = 4
bit
chip Min. Processing Gain = 4
CW-79© Copyright Roshdy H.M. Hafez 1996-2000
Transmitted Waveform
15 time slots = 10 ms
5 MHz
Different
codes
Frame
One user may consume: • One or more time slot on a code• The whole code (15 slots), or• Several codes
CW-80© Copyright Roshdy H.M. Hafez 1996-2000
The FDD Mode
The DS mode uses Frequency Division Duplexing (FDD)
5 MHz
Frame
5 MHz
80 MHz
MobilesTo
Base
BaseTo
Mobiles
CW-81© Copyright Roshdy H.M. Hafez 1996-2000
The TDD Mode
The TDD mode uses Time Division Duplexing
5 MHz
Frame
Mobiles To Base
Base To Mobiles
CW-82© Copyright Roshdy H.M. Hafez 1996-2000
Error Correcting Codes
Three Options
(1) Convolutional coding
1/3 CC(3,1,9,557,663,711)
1/2 CC(2,1,9,561,753)
(2) Turbo Coding
1/3 or 1/2
(3) Service-Specific Coding
-310 BERRequired =
-610 BERRequired =
32kbps Speed High >
CW-83© Copyright Roshdy H.M. Hafez 1996-2000
Rate Matching
STATIC DYNAMIC
Up Link & Down Link
Matched the total symbol rate to the rate of the physical data stream.
Up Link Only
Slow. Activated when adding or removing Transport Channels
Fast. Every 10 ms
Puncturing
Symbol repetition
Matched the total instantaneous symbol rate to the rate of the physical data
stream.
Unequal symbol Repetition
Links
Speed
Why ?
How ?
CW-84© Copyright Roshdy H.M. Hafez 1996-2000
Downlink Spreading and Modulation
Serialto
Parallel
p(t)
p(t)
Channelizationcode
Scramblingcode
Cos(ωt)
Sin(ωt)
Pulse shapingFilter
(RC with 0.22 Roll-off)
Data
DPDCH&
DPCCH
Dedicated Physical Channel
CW-85© Copyright Roshdy H.M. Hafez 1996-2000
Spreading and Scrambling
4The I & Q channels are spread by the same code.
4 It is one of a set of orthogonal codes known as the "channelization codes".
4The I & Q channels are also scrambled using the same scrambling code
4The scrambling code is "Cell Specific"
CW-86© Copyright Roshdy H.M. Hafez 1996-2000
Channelization Codes
C1,1 = (1)
C2,1 = (1,1)
C2,2 = (1,-1)
C4,1 = (1,1,1,1)
C4,2 = (1,1,-1,-1)
C4,3 = (1,-1,1,-1)
C4,4 = (1,-1,-1,1)
C8,1 = (1,1,1,1,1,1,1,1)
C8,2 = (1,1,1,1,-1,-1,-1,-1)
C8,3 = (1,1,-1,-1,1,1,-1,-1)
C8,4 = (1,1,-1,-1,-1,-1,1,1)
C8,5 = (1,-1,1,-1,1,-1,1,-1)
C8,6 = (1,-1,1,-1,-1,1,-1,1)
C8,7 = (1,-1,-1,1,1,-1,-1,1)
C8,8 = (1,-1,-1,1,-1,1,1,-1)
SF=1 SF=2 SF=4 SF=8 SF=16
CW-87© Copyright Roshdy H.M. Hafez 1996-2000
Channelization Codes (cont.)
C1,1 = (1)
C2,1 = (1,1)
C2,2 = (1,-1)
C4,1 = (1,1,1,1)
C4,2 = (1,1,-1,-1)
C4,3 = (1,-1,1,-1)
C4,4 = (1,-1,-1,1)
C8,1 = (1,1,1,1,1,1,1,1)
C8,2 = (1,1,1,1,-1,-1,-1,-1)
C8,3 = (1,1,-1,-1,1,1,-1,-1)
C8,4 = (1,1,-1,-1,-1,-1,1,1)
C8,5 = (1,-1,1,-1,1,-1,1,-1)
C8,6 = (1,-1,1,-1,-1,1,-1,1)
C8,7 = (1,-1,-1,1,1,-1,-1,1)
C8,8 = (1,-1,-1,1,-1,1,1,-1)
SF=1 SF=2 SF=4 SF=8 SF=16
CW-88© Copyright Roshdy H.M. Hafez 1996-2000
Scrambling Codes
1
2
3
32
0 1 2 15
16 17 18 31
32 33 34 47
496 497 498 511
512 codes
32 Groups x16 codes per group
1 2 3 16
18 stage m-sequence
18 stage m-sequence
1+x7+x18
1+x5+x7+x10+x18
xn
y
Cn
CW-89© Copyright Roshdy H.M. Hafez 1996-2000
Uplink Scrambling and Modulation
Dedicated Physical Channel DPDCH/DPCCH
p(t)
Cos(ωt)
Sin(ωt)
DPDCH
DPCCHp(t)
Re [ Cscramb] Im [ Cscramb]
CD
CC
+
-
+
+
Channelizationcodes
CW-90© Copyright Roshdy H.M. Hafez 1996-2000
Uplink Scrambling Codes
SHORT LONG
complex
Extended Kasami Set
complex
256 chips10 ms (one radio frame)
e.g. 40960 chips @1.096 Mcps
Identifies the mobile
Segments of sets of Gold sequences
Length
Class
Purpose Identifies the mobile
Short codes simplifies muti-user detection
Used in cells without mutli-user detection
CW-91© Copyright Roshdy H.M. Hafez 1996-2000
Initial Synchronization
Power ON
Slot Synchronization
Frame Synchronization& Group Identification
Scrambling CodeIdentification
Super Frame Synchronization& Read BCCH
Primary Synch code
Secondary Synch code
Primary CCPCH
Primary CCPCH
SCH
P-CCPCH
CW-92© Copyright Roshdy H.M. Hafez 1996-2000
The Synchronization Codes
16 Slots
Cp
Cs(k,1)
Cp
Cs(k,2)
Cp
Cs(k,16)
2560 chips(Slot)
256chips
CW-93© Copyright Roshdy H.M. Hafez 1996-2000
Properties of the Secondary SCH
A set of 17 orthogonal Gold codes of length 256 chips
{ C1,C2 ,C3 ,C4 ,C5 ,C6 ,C7 ,C8 ,C9 ,C10 ,C11 ,C12 ,C13 ,C14 ,C15,C16,C17 }
A secondary SCH SEQUENCE is made of 16 codes selected out of the set of 17 codes
e.g. ( C1C1C2 C11C6C3C15C7 C8C8C7C15C3C6C11C2 )
There are 32 sequences
They are selected carefully to have the following properties
Cyclic shift of any sequence does not look like any other sequence
Any cyclic shift of a sequence does not look like itself with any other cyclic shift
The 32 sequences are used for the initial cell search
CW-94© Copyright Roshdy H.M. Hafez 1996-2000
Properties of the Secondary SCH
4The Primary SCH is the same in all cells (sectors)
4The "mobile" searches for the unique code of the P-SCH
time
Slot2560 chips
Primary synch code256 chips
Base "b"
Base "a"
Cp
CW-95© Copyright Roshdy H.M. Hafez 1996-2000
Processing the Primary SCH
Matched FilterCp (256 chips)
Rx signal Accumulateover Tslot
Non-coherent
SelectMax.
Slottiming
Tslot Tslot
Tslot
BaseA
BaseB
BaseC
CW-96© Copyright Roshdy H.M. Hafez 1996-2000
Frame Synchronization
4The mobile uses the secondary SCH for frame synchronization
4In this stage, the slot timing is known
time
Frame
Ck,1 Ck,2 Ck,3 Ck,4Ck,16 Ck,16 Ck,1
TT/10
CW-97© Copyright Roshdy H.M. Hafez 1996-2000
Processing the Secondary SCH
MF C1
MF C2
MF C3
MF C17
16 Slots
SelectLargestin each
slot
C i Ck Cm Cn
Most Likely Code Sequence
CW-98© Copyright Roshdy H.M. Hafez 1996-2000
Processing the Secondary SCH (cont.)
16 Slots
C i Ck Cm Cn
Most Likely Code Sequence
16 cyclicshifts
32Groups
Compare to all512 Sequences
Group&
ShiftIdentified
CW-99© Copyright Roshdy H.M. Hafez 1996-2000
Processing the Secondary SCH (cont.)
10 ms (4096 chips @ 4.096 Mc/s)
8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12 8 12
One cycle of the scrambling code
Pilot Data
Integrate over a symbol period
Candidate scramble code #1
Integrate over a symbol period
Candidate scramble code #2
Integrate over a symbol period
Candidate scramble code #16
P-CCPCH
Magnitude Accumulate
Magnitude Accumulate
Magnitude Accumulate
Sel
ect L
arge
st
CW-100© Copyright Roshdy H.M. Hafez 1996-2000
The Random Access Channel
• Collision Risk• with some code division• protection
CW-101© Copyright Roshdy H.M. Hafez 1996-2000
The Random Access Burst
Random access burst
Offset
11.25 ms1.25 ms
Message = 10 ms
Idle time = 0.25 msPreamble = 1 ms
One burst
CW-102© Copyright Roshdy H.M. Hafez 1996-2000
Spreading and Modulation of the Random Access Channel
p(t)
Cos(ωt)
Sin(ωt)DataPart
Complexspreading
p(t)
CD
CC
R
I
ControlPart
Complex cell-specificscrambling code
Real [signature]
Cpreamb
Imag [signature]
1
2
3
1
2
3Position 1: 1 ms
Position 2: 0.25 ms
Position 3: 10 ms
CW-103© Copyright Roshdy H.M. Hafez 1996-2000
WCDMA vs. CDMA2000
Spreading and Identifying individual users:
• Both systems use scrambling codes (long) and channelization codes (short & orthogonal).
Identifying Cells:
• Cdma2000 uses the shifted complex short code
• Cells operate in an asynchronous mode. Cells are identified by groups of orthogonal Gold codes
Power Control:
• Both systems propose forward and reverse link closed loop power control using pilots
• Cdma2000 uses 800 bps & continuous pilot
• W-CDMA uses 1600 bps and pilot symbols
Coding & Modulation:
• Similar techniques with different framing parameters
CW-104© Copyright Roshdy H.M. Hafez 1996-2000
UWC-136
§ The four modes of UWC-136
§ North American TDMA, IS-136 and IS-136+
§ Enhanced air interface
§ The high speed outdoor mode
§ The high speed indoor mode
§ High speed packet mode
CW-105© Copyright Roshdy H.M. Hafez 1996-2000
What is UWC-136?
UWC-136
Circuit&
Packet
North-America'sTDMA
GSM
CW-106© Copyright Roshdy H.M. Hafez 1996-2000
The Modes of UWC-136
136 136+GPRS
136HS-O HS-I
GSM GPRS EDGE
UWC-136
200 kHz
30 kHz 1.6 MHz200 kHz
CW-107© Copyright Roshdy H.M. Hafez 1996-2000
Basic Characteristics of IS-136 / IS-136+
§ The RF channel bandwidth is 30 kHz
§ RF channels are paired for full duplex operation (FDD)
§ Each channel is divided into 40 ms time frames
§ Each frame has 6 time slots
IS-136
30 kHz
40 ms frametime
frequency
CW-108© Copyright Roshdy H.M. Hafez 1996-2000
Full Rate Frame Format
Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6
972 symbols per frame @ 24.3 ks/s = 40 ms
1 2 3
§ Three users share a carrier§ Each user is assigned two time slots§ The slots for the three users are interleaved
CW-109© Copyright Roshdy H.M. Hafez 1996-2000
Half, Full, Double and Triple Rates
Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6
972 symbols per frame @ 24.3 ks/s = 40 ms
Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6
Full Rate
Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6
Double Rate
Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6
Triple Rate
Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6
Half Rate
CW-110© Copyright Roshdy H.M. Hafez 1996-2000
IS-136 Modulation Methods
§ Two modulation methods are allowed:
1. π/4-DQPSK [45-degrees-Differential Quadrature Phase Shift Keying]
2. 8-PSK [8 phases Phase Shift Keying]
§ The first method, π/4-DQPSK, yields 2 bits per transmitted symbol
§ The second method, 8-PSK, yields 3 bits per transmitted symbol [50% increase in data rate]
CW-111© Copyright Roshdy H.M. Hafez 1996-2000
ππ/4-DQPSK
-π/401
π/400
3π/410
-3π/411
∆ΦYX
S/PDifferential
PhaseEncoder
LPF
LPF
A cos ωt
-A sin ωt
Data S(t)
X
Y
I
Q
nnn
ntAtS
φ∆+φ=φ
φ+ω=
−1
)cos()(
CW-112© Copyright Roshdy H.M. Hafez 1996-2000
ππ/4-DQPSK Phase Trajectory
0
45
90
135
180
-180
-135
-90
-45
1 2 3 4 5 6 7 8 9 10 11
1 1 0 1 0 0 1 0 1 1 1
1 0 1 0 0 1 0 1 1 1 0
X
Y
12
3
4
5
6
7
89 10
11-45o-135o
+135o +45o
CW-113© Copyright Roshdy H.M. Hafez 1996-2000
8-PSK Modulation
8-PSK phase constellation
§ 3 bits per phase (symbol)
§ All phase transitions are allowed
§ Absolute bits-to-phase mapping
§ Grey coding is used
CW-114© Copyright Roshdy H.M. Hafez 1996-2000
8-PSK Modulation
−π/4011
−π/2001
−3π /4101
π100
3π/4000
π/2010
π/4110
0111
ΦZzYkXk
)],,(cos[ kkkk zyxI Φ=
)],,(sin[ kkkk zyxQ Φ=
CW-115© Copyright Roshdy H.M. Hafez 1996-2000
IS-136 Channels
Channels
Digital Control Channel
DCCH
BCCH
SPACH
RACH
SCF
Digital Traffic Channel
DTC
Voice
Data
CW-116© Copyright Roshdy H.M. Hafez 1996-2000
The DCCH
TDMA frame = 40 ms
§ The DCCH occupies slots #1 and 4 on one carrier in a sector.
§ At the RF level, it appears as any other full-rate TCH.
DCCH
TCH
Analog
f1
f2
fN
fM
CW-117© Copyright Roshdy H.M. Hafez 1996-2000
The IS-136 Super Frame
§ Super frame is a group of 16 TDMA frames.
§ It has 96 time slots.
§ The DCCH occupies 32 TDMA slots.
§ The purpose of the super frame is to organize the DCCH logical channels in a recognizable pattern.
§ The first slot of a super frame is always a “Fast” broadcast message.
Super frame = 640 ms = 16 TDMA frames
TDMA frame = 40 ms
CW-118© Copyright Roshdy H.M. Hafez 1996-2000
Multiplexing Different DCCH Channels
One Super Frame
F
TDMA frame
F E E E E RF
SPACH channelsReservedBCCH
CW-119© Copyright Roshdy H.M. Hafez 1996-2000
Uplink/Downlink Arrangement
One Super Frame
SPACH channelsRSVD
BCCH
EF
RACH
Downlink
Uplink
CW-120© Copyright Roshdy H.M. Hafez 1996-2000
Some Enhanced Characteristics of IS-136
§ Three Vocoder techniques
§ Two interleaving schemes:
− Robust 2-block interleaving
− Low-delay one block interleaving
§ The RF channel bit rate is:
− 72.9 kbps on coherent 8-PSK
− 48.6 kbps on coherent DQPSK
§ A high data rate user can use more than one full rate channel (i.e. more than two slots per frame)
§ Power control is provided
§ Pilot symbols for coherent detection
CW-121© Copyright Roshdy H.M. Hafez 1996-2000
Uplink Frame Format
FullRate
DoubleRate
TripleRate
π/4 DQPSK
8-PSK
Primary
Secondary
Initial Primary
Subsequent Primary
Secondary
CW-122© Copyright Roshdy H.M. Hafez 1996-2000
Downlink Frame Format
Full Rate
CW-123© Copyright Roshdy H.M. Hafez 1996-2000
Downlink Frame Format (cont.)
DoubleRate
TripleRate
CW-124© Copyright Roshdy H.M. Hafez 1996-2000
IS-136-HS-O High Speed for Outdoor
§ IS-136-HS-O targets low-speed outdoor users
§ It is a derivative of the GSM standard
§ The RF bandwidth is 200 kHz/carrier
§ It is a "Packet-oriented" technique
§ It uses three different modulation methods:
1. GMSK
2. 8-PSK
CW-125© Copyright Roshdy H.M. Hafez 1996-2000
Slot 0 Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6 Slot 7
One TDMA frame = 1250 symbols = 4.615 ms
§ 8 Slots per frame
§ The slot duration is 576.92 µµs
§ Number of bits/frame depends on the modulation:
- GMSK à 1250 bits
- 8-PSK à 3750
§ Transmission rate = 270.833 ks/s
§ IS-136-HS-O operates in a packet mode
§ The parameters are adopted from GSM
IS-136-HS- Frame
CW-126© Copyright Roshdy H.M. Hafez 1996-2000
RB0 RB1 RB2 X RB3 RB4 RB5 X
Slot 0 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6 Slot 7Slot 1
One TDMA frame = 1250 symbols = 4.615 ms
26 Sub-Multi-Frame Structure
Radio Block
RB0-RB2 X RB3-RB5 X RB6-RB8 X RB9-RB11 X
52 Sub-Multi-Frame Structure
IS-136-HS-O Multi-Frame Structure
CW-127© Copyright Roshdy H.M. Hafez 1996-2000
§ This is very similar to the GSM burst format
§ Coding and interleaving are done across 4 bursts
TS = Trail SymbolsIS = Information SymbolsTSS = Training Sequence SymbolsGP = Gap Symbols
TS IS ISTSS TS GP
576.92 µs
3 58 26 58 3 8.25
IS-136-HS-O Burst Format
CW-128© Copyright Roshdy H.M. Hafez 1996-2000
2--1612313591 PCS-6
926231061612311491/2PCS-5
692207661612310321/2PCS-4
27816626161238251/2PCS-3
013846161236861/2PCS-2
213866161234561/3PCS-1
8-PSK
0--161234311GCS-4
2206764161233151/2GCS-3
1325884161232711/2GCS-2
0456440-31841/2GCS-1
Punct.
bits
Coded
bits
Tail
bits
BCS
bits
Coded
USF
USF
bits
Input
bits
Mother
code
Coding
bits
GMSK
IS-136-HS-O Coding & Interleaving
CW-129© Copyright Roshdy H.M. Hafez 1996-2000
1.0
0.73
0.64
0.49
1.0
0.829
0.746
0.596
0.496
0.329
69.269.28-PSKPCS-6
11.222.8GMSKGCS-1
14.522.8GMSKGCS-2
16.722.8GMSKGCS-3
22.822.8GMSKGCS-4
57.3569.28-PSKPCS-5
51.669.28-PSKPCS-4
41.2569.28-PSKPCS-3
34.369.28-PSKPCS-2
22.869.28-PSKPCS-1
Radio Interface Rate/Slot (kb/s)
Gross Rate (kb/s)
ModulationEffective Code Rate
Service Name
Information Rates
CW-130© Copyright Roshdy H.M. Hafez 1996-2000
datablockheader
CRC
Coding
Puncturing
Interleaving
0 2 3 4 5 6 71 0 2 3 4 5 6 71 0 2 3 4 5 6 71 0 2 3 4 5 6 71
Mapping Data Onto the Physical Layer
CW-131© Copyright Roshdy H.M. Hafez 1996-2000
§ IS-136-HS-I targets indoor users
§ The RF channel bandwidth is 1.6 MHz/carrier, which is 8 times wider than GSM
§ Frames have GSM structure but are clocked 8 times faster.
§ It is a "Packet-oriented" technique
§ It uses two different modulation methods:
1. Quaternary Offset QAM (Q-O-QAM)
2. Binary Offset QAM (B-O-QAM)
IS-136-HS-I High Speed for Indoor
CW-132© Copyright Roshdy H.M. Hafez 1996-2000
0
Hyper frame = 2048 super frames = 3 Hr. 28 min. 53 s. 760
1 2 3 4 5 2045 2046 2047
0 1 2 3 48 49 50
Super frame = 1326 TDMA frames
0 1 2 3 23 24 25
26 Multi-frame = 26 TDMA frames
1 TDMA frame = 64 short frames = 16 long frames = 4.615 ms
IS-136-HS-I Frames
CW-133© Copyright Roshdy H.M. Hafez 1996-2000
Short burst = 1/64 of TDMA = 72.1 µµ s
T3
Data72
Training27
Data72
T3
GP10.5
long burst = 1/16 of TDMA = 228 µµ s
T3
Data353
Training27
Data353
T3
GP11
IS-136-HS-I Long and Short Bursts
CW-134© Copyright Roshdy H.M. Hafez 1996-2000
IS-136-HS-I Coding Parameters
CW-135© Copyright Roshdy H.M. Hafez 1996-2000
Binary-Offset-QAM Quaternary-Offset-QAM
IS-136-HS-I Modulation Methods
CW-136© Copyright Roshdy H.M. Hafez 1996-2000
Summary of UWC-136 Environments
IndoorIS-136HS-I
1.6 MHz
OutdoorSmall cells
IS-136-HS-O200 kHz
EverywhereIS-13630 kHz
CW-137© Copyright Roshdy H.M. Hafez 1996-2000
UWC-136 Packet Mode
§ The "Packet Mode" is over 200-kHz RF channels
§ For GSM operators, the transition is simple
§ For IS-136 operators, some 30-kHz voice channel must be replaced by GSM-like channels
§ The packet mode uses EDGE (Enhanced Data rate for GSM evolution).
§ The packet network is called GPRS (Generalized Packet Radio System).
CW-138© Copyright Roshdy H.M. Hafez 1996-2000
Generalized Packet Radio System (GPRS)
MobilityManagement
MediaAccessControl
RadioResource
Management
CW-139© Copyright Roshdy H.M. Hafez 1996-2000
GPRS Network Model
OtherPLMN
SGSN
SGSN
SGSN
GGSN
GGSN
GGSNPublic Data
Network
IPNetwork
Radio AccessNetwork
CW-140© Copyright Roshdy H.M. Hafez 1996-2000
GPRS Protocol Stack
Application
IP/X.25
SNDCP
LLC
RLC
MAC
SNDCP
Physical
MAC
Physical
Networkservice
L1bis
BSSGPRLC
Relay
NetworkService
L1bis
L2
L1
BSSGP
LLC
GTPSNDCP
Relay
UDP/TCP
IP
L2
L1
UDP/TCP
IP
Application
IP/X.25
GTP
MS BSS SGNS GGNSUm Gb Gn
CW-141© Copyright Roshdy H.M. Hafez 1996-2000
1. Initial Systems Acquisition
2. Hierarchical Cell Structures
3. DCCH Selection and Camping
4. DCCH Reselection
5. Registration
6. Mobile Assisted Channel Assignment
7. Mobile Assisted Hand-Off
IS-136 Network Procedures
CW-142© Copyright Roshdy H.M. Hafez 1996-2000
§ At "service activation", the mobile may download what is known as: Intelligent Roaming Database (IRDB)
§ The Mobile also maintains a History List of last used DCCH frequencies
SID'sSOC's
Preferred systemsParameters
BandsEtc….
IRDB
HistoryList
Recent DCCH's
Initial System Acquisition
CW-143© Copyright Roshdy H.M. Hafez 1996-2000
§ Upon "power up", the mobile searches for service
§ The mobile follows the simplified flow chart shown
Power Up
CheckHistory List
Check all bandsIn IRDB
Camp&
Register
Y
Y
N
N
CellularPCS
DigitalAnalog
Own service providersOther service providers
No Service
Check otherpossible bands
N
Y
Initial System Acquisition (cont.)
CW-144© Copyright Roshdy H.M. Hafez 1996-2000
SSYNC SCF SCFCSFPData
28 12 130 12 130 10 2
Data
CDLSYNC SACCH SCDVCCData Data
28 12 130 12 130 1 11
DCCH
DTC
Detecting the DCCH
CW-145© Copyright Roshdy H.M. Hafez 1996-2000
Power
Scan History List DCCH?
Scan remaining probability
blocks
Camping?
Camp & Register on DCCH
DTC?
Scan forACC
Y
N
Y
N
ACC?Y
N
DCCHPointer ?
Camping?
Camp & Register on ACC
DCCH? Camping?Y
N
YN
N
Scan remaining CDL
frequenciesDCCH? Camping?
Y
NNo Service
Y
N
Y
N
Scanning and Camping
CW-146© Copyright Roshdy H.M. Hafez 1996-2000
Umbrella
Macro
Micro
§ In any given location, the mobile may be covered by several cells of different sizes
§ IS-136 supports the notion of establishing hierarchy of preferences
Hieratical Cellular Structure
CW-147© Copyright Roshdy H.M. Hafez 1996-2000
Assign
Is there a preferred cell with adequate
camping?
Is there a regular cell with adequate
camping?
Is there a non-preferred cell with
adequate camping?
Noservice
Y
Y
Y
N
N
N
Preferred, Regular & Non-Preferred Cells
CW-148© Copyright Roshdy H.M. Hafez 1996-2000
§ The mobile is constantly evaluating The DCCH channels in neighboring cells (sectors)
§ The mobile uses "Broadcast Neighboring Lists" to find the location of neighbor's DCCH.
§ The decision to "Reselect" a DCCH depends on many factors, including the hieratical preference
BNList
Reselecting the DCCH
CW-149© Copyright Roshdy H.M. Hafez 1996-2000
DCCH800 MHz
DCCH1900 MHz
ACC
DCCH800 MHz
DCCH1900 MHz
ACC
Known LocationsPointers
Digital verification color codeDVCC
Private System Identification (option)PSID
Parameters related to hand-offThreshold values
Public or private Network
Cell preferenceCell descriptors
RF channelChannel Number
FunctionParameter
Example of Neighbor List
Neighbors Cell List
CW-150© Copyright Roshdy H.M. Hafez 1996-2000
§ IS-136 honors AMPS and IS-54 registration schemes, but it adds new features
§ Two channels are involved:
- RACH: Uplink
- ARCH: Downlink
• Power up• Periodic• Location Area
• Power down• New system• Reselection of DCCH/ACC• Forced• User group• Change of frequency band• TMSI timeout• Deregistration
AMPS/IS-54 Additional
Registration Types
System Registration
CW-151© Copyright Roshdy H.M. Hafez 1996-2000
§ In the DCCH camping state, the mobile monitors a range of frequencies and determine their signal quality
§ The mobile periodically reports the measurements back to the base station.
§ The accumulated knowledge about the mobile environment is used to select the traffic channel.
§ The MACA functions fall into two categories:
- Long-Term
- Short-Term
Mobile Assisted Channel Selection
CW-152© Copyright Roshdy H.M. Hafez 1996-2000
RI I I R I I R I TI I
f1 f2 f3
Frequencies to be scanned
Command to measure RSSI on some frequencies
Report every second
Mobile Assisted Channel Hand Off
CW-153© Copyright Roshdy H.M. Hafez 1996-2000
3G Networks
§ The concept of core networks
§ Families of core networks with universal interfaces
§ IP-based network models
§ Internet traffic models
§ Wireless Internet proxy communications
§ Future directions
CW-154© Copyright Roshdy H.M. Hafez 1996-2000
Evolution of Wireless Networks
Present Future
• Wideband• Narrowband
• Multimedia• Voice
• High data rates• Low data rate
• IP-centric• Circuit-switched
• Harmonized standards
• Multi-standards
• Hierarchical, isolated networks
• Integrated Networks
CW-155© Copyright Roshdy H.M. Hafez 1996-2000
Key Network Characteristics
§ Backward compatibility to 2G services
§ Support for Multi-mode terminals
§ WRC-99 outlined the need for Global Radio Control Channel (RCC) to help in international roaming.
§ The global RCC is expected to broadcast helpful information, including:
§ IMT-2000 bands
§ Clocks and timing references
§ Identifications of public and private networks
§ Availability of services …etc
§ 3G networks will evolve from existing networks
§ It is expected that the network aspects will converge over the next three years
CW-156© Copyright Roshdy H.M. Hafez 1996-2000
3G Network Interface Model
RAN CNOtherCN's
l The CN-CN interface is key for global roaming :
l ITU study group 11 (ITU-T-SG-11) is currently investigating a common signaling protocol for this interface.
CN-CNRAN-CNMT-RANUIM-MT
UIM MT RAN CN CN
UIM =User Interface ModuleMT = Mobile TerminalRAN= Radio Access NetworkCN =Core Network
RTT
CW-157© Copyright Roshdy H.M. Hafez 1996-2000
Interworking Scenarios
l Ultimate goal
l No Interworking facilities
l Unlikely
C
A B
Common NNI
CommonNNI
CommonNNI
CommonNNI
A
B
IWF IWF C
IWF
l Different network protocols
l One IWF per network
l The IWF converts into a common protocol
A
B
C
l Different network protocols
l One IWF per Interface
l IWF's are different
IWF IWF
IWF
CW-158© Copyright Roshdy H.M. Hafez 1996-2000
Two Major Network Models
IS-41-C GSM-MAP
SS7
North AmericaIS-95
IS-136AMPS
EuropeMany other countries
GSM
CW-159© Copyright Roshdy H.M. Hafez 1996-2000
The GSM Network Model
VLR EIRHLRVLR
MSC
BSC
MSC
BS
BSBS
PSTN
G
E
B F
DC
A
Um
Ai
MS
AC
H
ISDNDi
Abis
MS= Mobile StationBS = Base StationBSC = Base Station ControllerMSC= Mobile Switching CenterHLR= Home Location RegistryVLR= Visitor Location RegistryAC = Authentication CenterEIR= Equipment Identity RegistryPSTN= Public Switched Telephone NetworkISDN= Integrated Services Digital Network
CW-160© Copyright Roshdy H.M. Hafez 1996-2000
The GSM System Architecture (cont.)
4The Public Land Mobile Network (PLMN) covers a large area.
4 It interfaces with other networks through Gateway MSC
4The PLMN is divided into sub-areas, each is served by one MSC.
4The MSC could be internal to the PLMN or could be a gateway MSC
PLMN
G-MSC
G-MSC
MSC
MSC
G-MSC
CW-161© Copyright Roshdy H.M. Hafez 1996-2000
The MSC Area
4The MSC area consists of one MSC and several BSS's
4The MSC provides the external interface, either directly or through a Gateway MSC
4Each MSC is connected to a Visitor Location Registry (VLR)
4The MSC also has access to a Home Location Registry (HLR) and Equipment Identification Registry (EIR)
MSC
VLRHLREIR
BSS BSS
BSS BSS
BSS
CW-162© Copyright Roshdy H.M. Hafez 1996-2000
The MSC Area (cont.)
4Each MSC is connected to only one VLR.
4But one VLR could serve more than one MSC
4There are few HLR is the PLMN. One HLR usually serves several MSC's
4EIR is usually linked to the HLR. There are few EIR's in the entire PLMN
MSC
VLRHLREIR
MSC
MSCMSC
MSC
VLRVLR
VLR
CW-163© Copyright Roshdy H.M. Hafez 1996-2000
The IS-41-C Network Model
CW-164© Copyright Roshdy H.M. Hafez 1996-2000
3G Mobile IP
•• Multitude of applicationsMultitude of applications
•• Communication amongst “things”Communication amongst “things”
•• Varying QoS requirementsVarying QoS requirements
•• Differing performance Differing performance
characteristicscharacteristics
•• Different devicesDifferent devices
•• Distinct capabilitiesDistinct capabilities
•• Battery lifeBattery life
Voice
Web
Conferencing
E-commerce
Audio InternetWirelessAccessNetwork
CW-165© Copyright Roshdy H.M. Hafez 1996-2000
Transcoding
§ Application: WWW browsing
§ Problems:
Ø varying device characteristics
Ø limited and changing bandwidth
§ Solution:
Ø Adaptive transcoding techniques
• Image characteristics
• Device constraints
• Bandwidth limitations
• User preferences
Ø Optimize the document Format
WirelessProxy Server
Internet
Web
CW-166© Copyright Roshdy H.M. Hafez 1996-2000
Deployment Models
§ Evolving 2G into 3G
§ Spectrum requirements
§ Enabling technologies:
Ø Software Radio
Ø Adaptive antennas
Ø Advanced power control and hand-off strategies
CW-167© Copyright Roshdy H.M. Hafez 1996-2000
Evolving 2G into 3G
§ Cdma2000
Ø Existing 1.25 MHz channels can be used by 2G and 3G terminals
ØConversion does not prematurely sacrifice revenue producing 2G voice for the developing 3G data market
ØCdma2000 will experience the smoothest transition from 2G to 3G
ØMutli-Carrier can be deployed by grouping existing 2G carriers.
CW-168© Copyright Roshdy H.M. Hafez 1996-2000
Evolving 2G into 3G (cont.)
§ UWC-136
Ø GSM operators will have easier time introducing 3G services. The deployment will follow the GPRS model
ØGPRS 200 kHz packet channels are fully compatible with the GSM system
Ø IS-136 operators will have difficult dilemma. They need to remove several 30 kHz channels to introduce one 200 kHz GPRS channel
Ø The IS-136 operators put a limit of 1 MHz on the converted voice channels
CW-169© Copyright Roshdy H.M. Hafez 1996-2000
Evolving 2G into 3G (cont.)
§ WCDMAØWCDMA requires new band
Ø The minimum frequency band needed is 5 MHz (TDD mode)
Ø WCDMA is not backward compatible with any existing system
Ø Spectrum availability is important
Ø Japan will likely be the first country to fully implement WCDMA
CW-170© Copyright Roshdy H.M. Hafez 1996-2000
IMT-2000 Spectrum Allocation
§ WRC-92 identified the spectrum requirements of IMT-2000
§ The required spectrum was estimated at 230 MHz for both terrestrial and satellite segments.
1885 – 2025 & 2110 – 2170 MHz [Terrestrial]
1980 – 2010 & 2170 – 2200 MHz [Satellite]
§ Subsequence decision in WARC-97 led to some modifications in region 2
CW-171© Copyright Roshdy H.M. Hafez 1996-2000
IMT-2000 Spectrum Allocation (cont.)
CW-172© Copyright Roshdy H.M. Hafez 1996-2000
Spectrum Plans for Europe [UMTS Forum]
CW-173© Copyright Roshdy H.M. Hafez 1996-2000
WRC-2000
§ WRC-2000 will consider allocating additional spectrum
§ It is expected that additional 160 MHz will be designated for 3G
World Radio Communications 2000World Radio Communications 2000Istanbul, TurkeyIstanbul, Turkey
May 8 May 8 –– June 2, 2000June 2, 2000
CW-174© Copyright Roshdy H.M. Hafez 1996-2000
Enabling Technologies
§ Smart Antennas
§ Software Radio
§ Advanced MAC layer
§ Transcoding and proxy communications
CW-175© Copyright Roshdy H.M. Hafez 1996-2000
New Applications
BroadbandB-ISDN
IMT-2000 NetworkIMT-2000 Network
BSC
BSC
ATMSwitch
ATMSwitch
MATMSwitch
1 2 3 46
0D
# *1
B1C
A7 8
95
1 2 3 46
0D
# *1
B1C
A7 8
95
1 2 3 46
0D# *
1B
1CA7 8
95
MSC
CW-176© Copyright Roshdy H.M. Hafez 1996-2000
References[GW96] V.K.Grag and J.E.Wilkes, "W ireless and
Personal Communications Systems", Prentice Hall,1996
[Dix94] R.C.Dixon,"Spread spectrum systems withcommercial applications", third edition, Wiely inter-science, John W iley, 1994
[Pro89] J.G.Proakis,"Digital Communications", secondedition, McGraw Hill, 1989
[Rap90] T.S.Rappaport et.al,"900 MHz multipathpropagation measurements for US digital cellularradiotelephone", IEEE Trans. on Veh. Tech., pp.132-139, May 1990
[Rap95] T.S.Rappaport,"W ireless communications:principles and practice", IEEE press and PrenticeHall PTR, 1995.
[Red95] S.M.Redl et.al.,"An introduction to GSM",Artech House Publishers, 1995
[Sim94] M .K.Simon et.al.,"Spread spectrumcommunications handbook", the revised edition,McGraw Hill, 1994