Transcript week6-ee522x

3G Vision
 Universal global roaming
 Multimedia (voice, data & video)
 Increased data rates
 384 kbps while moving
 2 Mbps when stationary at specific locations
 Increased capacity (more spectrally efficient)
 IP architecture
http://www.3gpp.org/
1
International Standardization
 ITU (International Telecommunication Union)
 Radio standards and spectrum
 IMT-2000
 ITU’s umbrella name for 3G which stands for
International Mobile Telecommunications 2000
 National and regional standards bodies are
collaborating in 3G partnership projects
 ARIB, TIA, TTA, TTC, CWTS. T1, ETSI
 3G Partnership Projects (3GPP & 3GPP2)
 Focused on evolution of access and core
networks
2
IMT-2000 Vision Includes LAN, WAN and
Satellite Services
Global
Satellite
Suburban
Macrocell
Urban
Microcell
In-Building
Picocell
Basic Terminal
PDA Terminal
Audio/Visual Terminal
3
IMT-2000 Radio Standards
 IMT-SC* Single Carrier (UWC-136): EDGE
 GSM evolution (TDMA); 200 KHz channels; sometimes called “2.75G”
 IMT-MC* Multi Carrier CDMA: CDMA2000
 Evolution of IS-95 CDMA, i.e. cdmaOne
 IMT-DS* Direct Sequence Spread CDMA: W-CDMA
 from 3GPP; UTRAN FDD
 IMT-TC** Time Code CDMA
 from 3GPP; UTRAN TDD
 from China;
TD-SCDMA
 IMT-FT** FDMA/TDMA (DECT legacy)
* Paired spectrum;
** Unpaired spectrum
4
WCDMA Background and Evolution
3GPP Rel -99
12/99
2000
Japan
3GPP Rel 4
03/01
2001
2002
Europe
(precommercial)
3GPP Rel 5
(HSDPA)
03/02
2003
Europe
(commercial)
3GPP Rel 6
(HSUPA)
2H/04
2004
2005
HSDPA
(commercial)
3GPP Rel 7
HSPA+
06/07
Further
Releases, (LTE)
2006
2007
HSUPA
(commercial)
5
CDMA2000 Pros and Cons
 Evolution from original Qualcomm CDMA
 Now known as cdmaOne or IS-95
 Better migration story from 2G to 3G
 cdmaOne operators don’t need additional spectrum
 1xEVD0 promises higher data rates than UMTS, i.e. WCDMA
 Better spectral efficiency than W-CDMA
 CDMA2000 core network less mature
 cmdaOne interfaces were vendor-specific
 Hopefully CDMA2000 vendors will comply w/ 3GPP2
6
W-CDMA (UMTS) Pros and Cons
 Wideband CDMA
 Standard for Universal Mobile Telephone Service (UMTS)
 Committed standard for Europe and likely migration path
for other GSM operators
 Leverages GSM’s dominant position
 Requires substantial new spectrum
 5 MHz each way (symmetric)
 Legally mandated in Europe and elsewhere
 Fits into GMM (Global Multimedia Mobility) initiative from
ETSI
 requirements
 min. 144 kbit/s rural (goal: 384 kbit/s)
 min. 384 kbit/s suburban (goal: 512 kbit/s)
 up to 2 Mbit/s city
7
TD-SCDMA
 Time division duplex (TDD)
 Chinese development
 deployed in China
 Good match for asymmetrical traffic!
 Single spectral band (1.6 MHz) possible
 Costs relatively low
 Handset smaller and may cost less
 Power consumption lower
 TDD has the highest spectrum efficiency
 Power amplifiers must be very linear
 Relatively hard to meet specifications
8
Migration To 3G
3G
2.75G
Intermediate
Multimedia
2.5G
Multimedia
Packet Data
2G
Digital Voice
1G
Analog Voice
GPRS
GSM
EDGE
W-CDMA
(UMTS)
384 Kbps
Up to 2 Mbps
115 Kbps
NMT
9.6 Kbps
GSM/
GPRS
TD-SCDMA
(Overlay)
115 Kbps
2 Mbps?
TDMA
TACS
9.6 Kbps
iDEN
9.6 Kbps
iDEN
PDC
(Overlay)
9.6 Kbps
AMPS
CDMA 1xRTT
CDMA
14.4 Kbps
/ 64 Kbps
PHS
1984 - 1996+
1992 - 2000+
cdma2000
1X-EV-DV
PHS
(IP-Based)
144 Kbps
64 Kbps
2001+
2003+
Over 2.4 Mbps
2003 - 2004+
Source: U.S. Bancorp Piper Jaffray
9
UMTS architecture
 UTRA (UMTS Terrestrial Radio Access)
 UTRAN (UTRA Network): cell level mobility and Management.
 Radio Network Subsystem (RNS): (i.e. in GSM BSS)


RNC: Radio Network Controller (i.e. in GSM BSC)
NodeB: Base stationRadio Transceiver + Antennas (i.e. in GSM BTS)
 UE: User Equipment (i.e. in GSM MS)
 CN (Core Network): Global network
 inter system handover
 radio access independent (unaware of radio signaling and control)
Uu
UE
Iu
UTRAN
CN
10
UMTS Architecture: UE
 User Equipment consist of two parts:
 ME: Mobile Equipment
 USIM:UMTS Subscriber Identity Module “smartcard”
 Mobile Equipment consist of:
 Mobile Termination: carries out functions related to
radio transmission.
 Terminal Equipment: Hardware+User applications
Uu
USIM
TE
MT
ME
11
UMTS Architecture: Radio Network Subsystem
Radio Network
subsystem
UE
Core Network
 In comparison with GSM, the
UE
Uu
Node B
Iub
Node B
RNC
UE
CN
Iur
Iu
Node B
Node B
RNC
RNS
RNS performs a similar
function to that of BSS.
 Responsible for allocating
and releasing radio resources
to allow communication to
occur between UTRAN and
the UE.
 Iur interface is available for
soft handover
RNC
12
Serving and Drift RNC
•
•
•
•
CN is unaware of radio signaling
and control
For each user connected to the
network a particular RNC is
allocated as the Serving RNC, it
communicate with the CN for the
user.
During the connection the user
may roam outside the cells that
are controlled by the serving
RNC.
A second RNC (drift RNC)
provides the necessary radio
resources and communication
directly with the serving RNC
which maintains the connection
with the CN.
NodeB
Serving RNC
NodeB
RNC
Drift RNC
NodeB
RNC
CCN
NodeB
NodeB
13
3G Partnership Project (3GPP)
 3GPP defining migration from GSM to UMTS (W-CDMA)
 Core network evolves from GSM-only to support GSM, GPRS
and new W-CDMA facilities
 3GPP Release 99
 Adds 3G radios
 3GPP Release 4
 Adds softswitch/ voice gateways and packet core
 3GPP Release 5
 First IP Multimedia Services (IMS) w/ SIP & QoS
 3GPP Release 6
 “All IP” network
14
3G rel99 Architecture (UMTS) — 3G Radios
2G MS (voice only)
CN
BSS
E
Abis
PSTN
A
PSTN
B
BSC
Gb
BTS
C
MSC
Gs
VLR
GMSC
D
SS7
H
2G+ MS (voice & data)
IuCS
RNS
Gr
HLR
ATM
Iub
IuPS
RNC
AuC
Gc
Gn
SGSN
Gi
IP
PSDN
GGSN
Node B
3G UE (voice & data)
BSS — Base Station System
BTS — Base Transceiver Station
BSC — Base Station Controller
RNS — Radio Network System
RNC — Radio Network Controller
CN — Core Network
MSC — Mobile-service Switching Controller
VLR — Visitor Location Register
HLR — Home Location Register
AuC — Authentication Server
GMSC — Gateway MSC
SGSN — Serving GPRS Support Node
GGSN — Gateway GPRS Support Node
UMTS — Universal Mobile Telecommunication System
15
3G rel4 Architecture (UMTS) — Soft Switching
2G MS (voice only)
CN
GERAN
CS-MGW
A
Abis
Nc
Mc
BSC
Gb
BTS
PSTN
PSTN
Mc
B
C
MSC Server
Gs
2G+ MS (voice & data)
CS-MGW
Nb
BSS
VLR
GMSC server
D
SS7
H
UTRAN
RNS
IuCS
Gr
HLR
ATM
Iub
IuPS
RNC
AuC
IP/ATM
Gc
Gn
SGSN
Gi
PSDN
GGSN
Node B
3G UE (voice & data)
BSS — Base Station System
BTS — Base Transceiver Station
BSC — Base Station Controller
GERAN—GSM/EDGE Radio Access Network
RNS — Radio Network System
RNC — Radio Network Controller
UTRAN—UMTS Terrestrial Radio Access Network
CN — Core Network
MSC — Mobile-service Switching Controller
VLR — Visitor Location Register
HLR — Home Location Register
AuC — Authentication Server
GMSC — Gateway MSC
MGW — Media Gateway
SGSN — Serving GPRS Support Node
GGSN — Gateway GPRS Support Node
3GPP Rel.4 network architecture
UTRAN
(UMTS Terrestrial Radio
Access Network)
Circuit Switched (CS)
core network
MSC
Server
New option in Rel.4:
GERAN
(GSM and EDGE Radio
Access Network)
MGW
SGW
MGW
PS core as in Rel.’99
PSTN
SGW
GMSC
Server
3GPP Rel.4 network architecture
MSC Server takes care
of call control signalling
“Lower layer” protocol
conversion in SGW
(Signalling
RANAP GateWay)
/ ISUP
SS7 MTP
IP
Sigtran
MSC
Server
SGW
MGW
core
GMSC
Server
SGW
MGW
PS core as in Rel.’99
PSTN
The user connections
are set up via MGW
(Media GateWay)
Circuit Switched (CS)
network
Transcoder Free Operation (TrFO)
 Used in UMTS to improve voice quality by avoiding
unneeded transcoders
 like TFO but using packet-based core network
 Out-of-band negociation
 Select same codec at both ends during call setup
 Supports sudden channel rearrangement (handovers,
etc.) via signaling procedures
 When TrFO impossible, TFO can be attempted

e.g. transit between packet-based and circuit-based core
networks
19
TrFO + TFO Example
 2G handset to 3G handset: by combining TrFO and TFO, in-
path transcoders can be avoided
TRAU
2G PLMN
MSC
Radio Access
Network
2G MS
CS-MGW
CS-MGW
3G UE
C
D
GMSC Server
Radio Access
Network
MSC Server
3G Packet
Core Network
GSM Coding (TrFO)
T
F
O
[GSM Coding + TFO Sig] (lsb)
+ G.711 (msb) / 64 Kb
T
F
O
GSM Coding
D
C
20
3G rel4 Architecture (UMTS) — Soft Switching
2G MS (voice only)
CN
CS-MGW
A
Abis
Nc
Mc
BSC
Gb
BTS
CS-MGW
Nb
BSS
PSTN
B
C
MSC Server
Gs
PSTN
Mc
VLR
GMSC server
D
SS7
H
2G+ MS (voice & data)
IuCS
RNS
Gr
HLR
ATM
Iub
IuPS
RNC
AuC
IP/ATM
Gc
Gn
SGSN
Gi
PSDN
GGSN
Node B
3G UE (voice & data)
BSS — Base Station System
BTS — Base Transceiver Station
BSC — Base Station Controller
RNS — Radio Network System
RNC — Radio Network Controller
CN — Core Network
MSC — Mobile-service Switching Controller
VLR — Visitor Location Register
HLR — Home Location Register
AuC — Authentication Server
GMSC — Gateway MSC
MGW — Media Gateway
SGSN — Serving GPRS Support Node
GGSN — Gateway GPRS Support Node
3G rel5 Architecture (UMTS) -IP Multimedia
2G MS (voice only)
CN
CS-MGW
A/IuCS
Abis
Nc
Mc
BSC
Gb/IuPS
BTS
IuCS
B
C
VLR
GMSC server
D
SS7
ATM
Gr
IuPS
RNC
PSTN
H
RNS
Iub
PSTN
Mc
MSC Server
Gs
2G+ MS (voice & data)
CS-MGW
Nb
BSS
HSS
AuC
IP/ATM
Gc
Gn
Gi
SGSN
IP Network
GGSN
Node B
3G UE (voice & data)
IM-MGW
IMS
IMS — IP Multimedia sub-system
MRF — Media Resource Function
CSCF — Call State Control Function
MGCF — Media Gateway Control Function (Mc=H248,Mg=SIP)
MGW —Media Gateway
IM-MGW — IP Multimedia-MGW
Gs
PSTN
IP
Mg
MRF
Mc
MGCF
CSCF
22
IMS with 3GPP Release 5
 IMS will allow premium multimedia services
 Video, Audio / VoIP, application sharing etc.
 End-end; IP client directly in end user device
 SIP (Session Initiation Protocol) chosen as signaling / control protocol



Flexible syntax
Widely implemented, better interworking between networks (harmonisation)
Good support for proxy / control functions
 Uses the PS network as the bearer (signaling and data treated as PS data)
– rides on PS handover mechanisms to support roaming
 Mandates the use of IPv6 for session control (need transition techniques)
 In the future basic CS services can be offered via VoIP on PS and IMS
23
3GPP Rel.6 Objectives
 IP Multimedia Services, phase 2
 IMS messaging and group management
 Wireless LAN interworking
 Speech enabled services
 Distributed speech recognition (DSR)
 Number portability
 Other enhancements
24
UMTS bearer service architecture
TE
MT
UTRAN
CN Iu
edge node
UE
CN
gateway
TE
Core network
End-to-end service
Local b.s.
UMTS bearer service
Radio access bearer service
Radio b.s.
Radio Bearer
Iu b.s.
Ext. b.s.
CN b.s.
Backbone
Radio Access Bearer
25
What is a bearer?
Bearer: a bearer capability of defined capacity, delay and
bit error rate, etc. (as defined in 3GPP specs.)
Bearer is a flexible concept designating some kind of ”bit
pipe”
 at a certain network level (see previous slide)
 between certain network entities
 with certain QoS attributes, capacity, and traffic
flow characteristics
Four UMTS QoS Classes
 conversational, streaming, interactive, background
26
UMTS QoS (service) classes
Conversational
Streaming
Interactive
Background
low delay
reasonably low
delay
low round-trip delay
delay is not critical
low delay variation
basic QoS requirements
speech
video
telephony/
conferencing
video streaming
audio streaming
www applications
basic applications
store-and- forward
applications
(e-mail, SMS)
file transfer
27
Four UMTS QoS (service) classes
Conversational
Streaming
Interactive
Background
• low delay (< 400 ms) and low delay variation
• BER requirements not so stringent
• in the radio network => real-time (RT) connections
• speech (using AMR = Adaptive Multi-Rate speech coding)
• video telephony / conferencing:
ITU-T Rec. H.324 (over circuit switched connections)
ITU-T Rec. H.323 or IETF SIP (over packet switched
connections)
28
Four UMTS QoS (service) classes
Conversational
Streaming
Interactive
Background
• reasonably low delay and delay variation
• BER requirements quite stringent
• traffic management important (variable bit rate)
• in the radio network => real-time (RT) connections
• video streaming
UE
Source
• audio streaming
Buffer
video or audio information is buffered in the UE,
large delay => buffer is running out of content!
29
Four UMTS QoS (service) classes
Conversational
Streaming
Interactive
Background
• low round-trip delay (< seconds)
• delay variation is not important
• BER requirements stringent
• in the radio network => non-real-time (NRT) connections
• web browsing
• interactive games
• location-based services (LCS)
30
Four UMTS QoS (service) classes
Conversational
Streaming
Interactive
Background
• delay / delay variation is not an important issue
• BER requirements stringent
• in the radio network => non-real-time (NRT) connections
• SMS (Short Message Service) and other more advanced
messaging services (EMS, MMS)
• e-mail notification, e-mail download
• file transfer
31
UMTS Characteristics
 Does not assign a specific frequency to each user. Instead every channel










uses the full available spectrum. Individual conversations are encoded with
a pseudo-random digital sequence.
Support two basic modes: FDD and TDD modes
High chip rate (3.84 Mcps) and data rates (up to 2 Mbps)
Employs coherent detection on uplink and downlink based on the use
of pilot symbols
Inter-cell asynchronous operation
Fast adaptive power control in the downlink based on SIR
Provision of multirate services
Packet data
Seamless inter-frequency handover
Intersystem handovers, e.g. between GSM and WCDMA
Support for advanced technologies like multiuser detection (MUD) and
smart adaptive antennas
32
2100 MHz Utilization in Jordan for 3G:
1920
1930
1935
Umniah
2110
1945
Orange
2120
2135
1955
MHz
Zain
2145
2155
MHz
33
UMTS Terrestrial Radio Access
Network
34
UMTS Specifications
Channel Bandwidth
5 MHz
Duplex Mode
FDD and TDD
Downlink RF Channel Structure
Direct Spread (DS)
Chip Rate
3.84 Mcps
Frame Length
10 ms (38400 chips)
No. of slots/frame
15
No. of chips/slot
2560chips (Max. 2560 bits)
Spreading Modulation
Balanced QPSK (downlink), Dual-channel QPSK (uplink) Complex spreading circuit
Data Modulation
QPSK (downlink), BPSK (uplink)
Channel Coding
Convolutional and turbo codes
Coherent detection
• User dedicated time multiplexed pilot (downlink and uplink)
• common pilot in downlink
Channel Multiplexing in Downlink
Data and control channel are multiplexed
Channel Multiplexing in Uplink
• Control and pilot channel time multiplexed
• I&Q multiplexing for data and control channel
Multirate
Variable spreading and multicode
Spreading Factors
4-256 (uplink), 4-512 (downlink)
Power Control
Open and fast closed loop (1.5 kHz)
Spreading (downlink)
OVSF sequences for channel separation. Gold sequences 218 − 1 for cell and user
separation (truncated cycle 10 ms)
Spreading (uplink)
OVSF sequences. Gold sequence 241 for user separation (different time shifts in I and
Q channel, truncated cycle 10 ms)
Handover
Soft handover, Inter-frequency handover, etc.
35
Why CDMA?
 Higher capacity
 Improved performance in multipath by diversity
 Lower mobile transmit power = longer battery life
 Power control
 Variable transmission rate with voice activity detection




(VAD)
Allows soft handoff
Sectorization gain
High peak data rates can be accommodated
Combats other-user interference = lower reuse factors 1
36
Spreading and Scrambling codes in UMTS
 Physical channel operations:
 channelization: every bit is transformed into SF number
of chips
 scrambling: scrambling code is applied to the spread
signal
 In channelization operation, Orthogonal Variable
Spreading Factor (OVSF) codes are used to preserve
the orthogonality between the physical channels of
connections operating at different rates.
 The SF depends on the bit rate; high bit rate requires
low SF and vice versa
 Each user has its own scrambling code in the uplink
37
Cont.
 Scrambling code is related to a user
 Spreading code is related to the type of service at a given bit
rate
 Downlink scrambling code planning:
 max number of scrambling codes: 218 − 1, divided into 512
primary scrambling codes with 15 secondary scrambling
codes.
 each cell has been allocated only one primary scrambling
code.
 Downlink spreading code:
 max number of OVSF downlink spreading codes is 512
 all users in a cell share the available channelization codes in
the OVSF code tree
38
Spreading in WCDMA
Channelization
code
Scrambling code
Channel data
Channel bit
rate
Chip rate
Chip rate
(always 3.84 million chips/s)
Usage of code
Uplink
Downlink
Channelization code
Channel separation
User separation
Scrambling code
User separation
Cell separation
39
Spreading in WCDMA
Chip rate after spreading = 3.84 Mchips/s
Spreading factor (SF) is important in WCDMA
Chip rate = SF x channel bit rate
Uplink: DPCCH SF = 256, DPDCH SF = 4 - 256
Downlink: DPCH SF = 4 - 512
One bit consists
of 2 chips
One bit consists
of 256 chips
40
Spreading Codes
Channelization Code
Scrambling Code
Usage
UL: Separation of physical data
and control channels from same UE
DL: Separation of different users
within one cell
UL: Separation of terminals
DL: Separation of
cells/sectors
Length
UL:4-256 chips
DL:4-512 chips
38400 chips
No. of
codes
No. of codes under one scrambling code= SF UL: Several million
DL: 512
Code
Family
Orthogonal Variable Spreading Factor
Long 10ms code: Gold
code
Short code: Extended S(2)
code Family
Increase
B.W?
YES
NO
41
Channelization Codes
 In the Downlink Channelization Codes are used to distinguish between data (and
control) channels coming from the same BS
CC1, CC2
CC3, CC4
CC5, CC6, CC7
 In the Uplink Channelization Codes are used to distinguish between data (and control)
channels from the same UE
CC1 , CC2, CC3
CC1, CC2
CC1, CC2, CC3, CC4
42
Scrambling Codes
 In the Downlink, the Scrambling Codes are used to distinguish each cell
(assigned by operator – SC planning)
 In the Uplink, the Scrambling Codes are used to distinguish each UE
(assigned by network)
Cell “1” transmits using SC1
SC1
SC1
SC3
SC4
Cell “2” transmits using SC2
SC2
SC5
SC2
SC6
43
Downlink Scrambling Codes
 Used to distinguish Base Station transmissions on
Downlink


Each Cell is assigned one and only one Primary Scrambling Code (of 512)
Secondary Scrambling Codes may be used over part of a cell, or for other data
channels
8192 Downlink Scrambling Codes
Each code is 38,400 chips of a 218 - 1 (262,143 chip) Gold Sequence
Code Group #1
Code Group #64
Primary SC0
Primary SC7
Primary SC504
Primary SC511
Secondary
Scrambling
Codes
Secondary
Scrambling
Codes
Secondary
Scrambling
Codes
Secondary
Scrambling
Codes
(15)
(15)
(15)
(15)
44
Scrambling Code planning
 SC are organized in Code Groups.
 The first SC in each Code Group differs from the first SC in the
subsequent Code Group by a multiple of 8
64 Code Groups
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
...
...
...
...
...
...
...
...
...
...
...
...
500
501
502
503
504
505
506
507
508
509
510
511
45
Scrambling Code planning example
SC 48
SC 64
SC 0
SC 16
SC 56
SC 40
SC 8
SC 49
SC 24
SC 32
SC 1
SC 17
SC 65
SC 57
SC 41
SC 25
SC 9
SC 33
46
Uplink Scrambling Code
Uplink Scrambling Code Type depends on the Application
Random Access, Packet Access
Dedicated Traffic Connection
• Cell-specific Scrambling Code(s)
• UE-specific Scrambling Code(s)
• Code(s) are assigned by UTRAN
• Code(s) are assigned by UTRAN
• Code(s) are conveyed to UE
via the BCH or FACH channels
• Code(s) are conveyed to UE via the FACH channel
• 224 possible codes
• 8,192 PRACH codes
• 32,768 PCPCH codes
• Code allocation corresponds to
the cell’s DL scrambling code group
47
Channelization and Scrambling Codes
Example:
Pilot, Broadcast
Voice
Conversation
2 data channels
(voice, control)
SC1 + CC1 + CC2
SC1 + CCP + CCB
1 data channels
(control)
SC1 + CC3
Uplink
Packet Data
2 data channels
(14 kbps data, control)
SC4 + CC1 + CC2
2 data channels
(voice, control)
SC3 + CC1 + CC2
Pilot, Broadcast
SC2 + CCP + CCB
Videoconference
3 data channels
(voice, video, control)
SC2 + CC1 + CC2 + CC3
3 data channels
(voice, video, control)
SC5 + CC1 + CC2 + CC3
4 data channels
(384 kbps data, voice, video, control)
SC2 + CC4 + CC5 + CC6 + CC7
Videoconference
with Data
4 data channels
(384 kbps data, voice, video, control)
SC6 + CC1 + CC2 + CC3 + CC4
48