Transcript 3GPP general presentation

3GPP LTE presentation
3GPP LTE presentation
Kyoto May 22rd 2007
3GPP TSG RAN Chairman
1
3GPP LTE presentation
• Presentation Overview
– LTE Introduction
– Network Architecture
– The access network
• Physical Layer
• Layer 2 and above over the radio interface
– Control Plane
– User Plane
• Interface towards the Core Network
– Conclusion
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3GPP LTE presentation
LTE targets
•
•
•
•
•
•
•
Significantly increased peak data rates
Increased cell edge bitrates
Improved spectrum efficiency
Improved latency
Scaleable bandwidth
Reduced CAPEX and OPEX
Acceptable system and terminal complexity, cost and
power consumption
• Compatibility with earlier releases and with other systems
• Optimised for low mobile speed but supporting high mobile
speed
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3GPP LTE presentation
Peak data rate
• Goal: significantly increased peak data rates,
scaled linearly according to spectrum allocation
• Targets:
– Instantaneous downlink peak data rate of
100Mbit/s in a 20MHz downlink spectrum (i.e. 5
bit/s/Hz)
– Instantaneous uplink peak data rate of
50Mbit/s in a 20MHz uplink spectrum (i.e. 2.5
bit/s/Hz)
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3GPP LTE presentation
Mobility
• The Enhanced UTRAN (E-UTRAN) will:
– be optimised for mobile speeds 0 to 15 km/h
– support, with high performance, speeds between 15 and
120 km/h
– maintain mobility at speeds between 120 and 350 km/h
• and even up to 500 km/h depending on frequency
band
– support voice and real-time services over entire speed
range
• with quality at least as good as UTRAN
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3GPP LTE presentation
Spectrum issues
• Spectrum flexibility
– E-UTRA to operate in 1.25, 1.6, 2.5, 5, 10, 15 and 20 MHz
allocations…hence allowing different possibilities for refarming already in use spectrum
– uplink and downlink…
– paired and unpaired
• Co-existence
– with GERAN/3G on adjacent channels
– with other operators on adjacent channels
– with overlapping or adjacent spectrum at
country borders
– Handover with UTRAN and GERAN
– Handover with non 3GPP Technologies (CDMA 2000,
WiFi, WiMAX)
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3GPP LTE presentation
• Network Architecture
TE
R
MSC
GERAN
MT
C
HLR/AuC*
HSS*
EIR
SMS-GMSC
SMS-IWMSC
SMS-SC
Um
Gb, Iu
Rx+ (Rx/Gq)
Gr
Gf
Gs
Iu
TE
MT
R
BM-SC
Gi
Gn/Gp
Gi
PDN
GGSN
Mb
Uu
Gn
Ga
Billing
System*
SGSN
UE
Gx+ (Go/Gx)
Gmb
Gc
SGSN
UTRAN
AF
PCRF
Gd
Ga
Gy
IMSMGW
Mb
MRFP
OCS*
Wi
CGF*
Gm
IMS
P-CSCF
CSCF
Mw
CDF
Wf Wf
Intranet/
3GPP AAA
Proxy
Internet
Wa
WLAN
UE
Wd
Wa
WLAN Access
Network
Ww
D/Gr
Dx
Cx
HLR/
AuC*
HSS*
SLF
Wx
Dw
3GPP AAA
Server
Wm
OCS*
**
Wo Wy
Wg
WAG
Wn
PDG
Wp
Wz
Wu
Traffic and signaling
Signaling
CGF*
Billing
System*
Note: * Elements duplicated for picture
layout purposes only, they belong to the
same logical entity in the architecture
baseline.
** is a reference point currently missing
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3GPP LTE presentation
GERAN
Gb
GPRS Core
Iu
SGSN
PCRF
Rx+
UTRAN
S7
S3
S4
S6
HSS
Op.
S5a
S1
Evolved RAN
S5b
MME
3GPP
UPE
Anchor
IP
SGi
SAE
(IMS,
Anchor
PSS,
S2b
IASA
Serv.
etc…)
S2a
Evolved
Packet Core
Trusted non 3GPP IP
Access
ePDG
WLAN
3GPP IP
Access
WLAN
Access NW
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3GPP LTE presentation
The access network
• Generality
– The access network is simplified and
reduce to only the Base Station called
eNode B
– Physical layer is based on SC FDMA for
the Uplink and OFDMA for the Downlink
– Tow modes FDD and TDD considered
– MBMS part of the study
– Ciphering is handled within the eNode B
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3GPP LTE presentation
• Physical Layer
– Overview
Layer 3
Layer 1
Control / Measurements
Layer 2
Radio Resource Control (RRC)
Logical channels
Medium
(MAC)
Access
Control
Transport channels
Physical layer
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3GPP LTE presentation
• Physical layer details
– The Layer 1 is defined in a bandwidth agnostic
way, allowing the LTE Layer 1 to adapt to
various spectrum allocations.
– The generic radio frame for FDD and TDD has
a duration of 10ms and consists of 20 slots
with a slot duration of 0.5ms. Two adjacent
slots form one sub-frame of length 1ms. A
resource block spans either 12 sub-carriers
with a sub-carrier bandwidth of 15kHz or 24
sub-carriers with a sub-carrier bandwidth of
7.5kHz each over a slot duration of 0.5ms.
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3GPP LTE presentation
• Physical Layer details (continued)
– The physical channels defined in the downlink are the
Physical Downlink Shared Channel (PDSCH), the
Physical Downlink Control Channel (PDCCH) and the
Common Control Physical Channel (CCPCH). The
physical channels defined in the uplink are the Physical
Uplink Shared Channel (PUSCH) and the Physical Uplink
Control Channel (PUCCH).
– In addition, signals are defined as reference signals,
primary and secondary synchronization signals or
random access preambles.
– The modulation schemes supported in the downlink are
QPSK, 16QAM and 64QAM, and in the uplink QPSK,
16QAM and 64QAM. The Broadcast channel use only
QPSK
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3GPP LTE presentation
• Physical Layer (Continued)
– The channel coding scheme for transport
blocks in LTE is Turbo Coding with a coding
rate of R=1/3, two 8-state constituent encoders
and a contention-free quadratic permutation
polynomial (QPP) turbo code internal
interleaver. Trellis termination is used for the
turbo coding. Before the turbo coding,
transport blocks are segmented into byte
aligned segments with a maximum information
block size of 6144 bits. Error detection is
supported by the use of 24 bit CRC.
– Coexistence scenarios have been already done
for the downlink and result can be found in TR
36.942
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3GPP LTE presentation
• Physical Layer (Continued)
– The generic frame structure is applicable to
both FDD and TDD. Each radio frame is long
and consists of 20 slots of length , numbered
from 0 to 19 consists of 20 slots of length ,
numbered from 0 to 19. A sub-frame is defined
as two consecutive slots where sub-frame
consists of slots and
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3GPP LTE presentation
• Layer 2 and above over the radio interface
– Overall architecture
MME/SAE Gateway
MME/SAE Gateway
S1
S1
S1
S1
X2
E-UTRAN
eNB
eNB
X2
X2
eNB
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3GPP LTE presentation
• Layer 2 and above over the radio interface
– The eNode B hosts the following functions:
• Functions for Radio Resource Management:
–
–
–
–
Radio Bearer Control,
Radio Admission Control,
Connection Mobility Control,
Dynamic allocation of resources to UEs in both uplink and
downlink (scheduling);
• IP header compression and encryption of user data
stream;
• Selection of an MME at UE attachment;
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3GPP LTE presentation
• Layer 2 and above over the radio interface
Radio Bearers
ROHC
ROHC
ROHC
ROHC
Security
Security
Security
Security
Segm.
ARQ
Segm.
ARQ
PDCP
RLC
Segm.
ARQ
...
...
Segm.
ARQ
BCCH
PCCH
Logical Channels
Scheduling / Priority Handling
MAC
Multiplexing UE1
Multiplexing UEn
HARQ
HARQ
Transport Channels
: Layer 2 Structure at the eNode B
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3GPP LTE presentation
•
Layer 2 and above over the radio interface
– For the UE two states are considered
•
•
•
•
•
•
RRC_IDLE where:
UE specific DRX configured by NAS;
Broadcast of system information;
Paging;
Cell re-selection mobility;
The UE shall have been allocated an id which uniquely identifies the UE
in a tracking area;
– - No RRC context stored in the eNode B .
•
•
•
•
•
•
•
RRC_CONNECTED where:
UE has an E-UTRAN-RRC connection;
UE has context in E-UTRAN;
E-UTRAN knows the cell which the UE belongs to;
Network can transmit and/or receive data to/from UE;
Network controlled mobility (handover);
Neighbour cell measurements;
– - At PDCP/RLC/MAC level:
– - UE can transmit and/or receive data to/from network;
– - UE monitors control signalling channel for shared data channel to see if any
transmission over the shared data channel has been allocated to the UE;
– - UE also reports channel quality information and feedback information to eNode B;
– - DRX/DTX period can be configured according to UE activity level for UE power
saving and efficient resource utilization. This is under control of the eNode B
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3GPP LTE presentation
• Interface towards the Core network
– Generalities
• Two interfaces:
– S1 for the Control plane
– X1 for the User plane
• Additional interface in between eNode Bs: X2
– Including both Control and User plane
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3GPP LTE presentation
• Interface towards the Core network
eNB
Inter Cell RRM
RB Control
Connection Mobility Cont.
Radio Admission Control
MME
eNB Measurement
Configuration & Provision
NAS Security
Dynamic Resource
Allocation (Scheduler)
Idle State Mobility
Handling
RRC
PDCP
SAE Bearer Control
RLC
SAE Gateway
MAC
S1
PHY
Mobility Anchoring
E-UTRAN
EPC
internet
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3GPP LTE presentation
• Interface towards the Core network
S1-AP
SCTP
IP
Data link layer
Physical layer
S1 Interface Control Plane (eNB-MME)
• For the X1 interface Still under investigation
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3GPP LTE presentation
• eNode B X2 Interface
– This interfaces allows inter-eNode B handover
X2-AP
SCTP
IP
Data link layer
Physical layer
X2 Interface Control Plane
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3GPP LTE presentation
Conclusion
• Lot of progress made recently are not
incorporated in this presentation
• However the timescale for completion of
the specification is still foreseen to be in
September 2007
• All documentation referred to is available
At :
http://www.3gpp.org/ftp/Specs
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3GPP LTE presentation
Thanks for your attention
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3GPP LTE presentation
Annex
• Structure of the documentation for the
physical layer specification
To/From Higher Layers
36.212
Multiplexing and channel
coding
36.211
36.213
36.214
Physical Channels and
Modulation
Physical layer procedures
Physical layer –
Measurements
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