1. GSM TOWARDS LTE NETWORKS
Lecture # 6

2. LTE

3. Many names ... LTE - Long Term Evolution
Introduction
Many names ...
LTE - Long Term Evolution
 eUTRAN
SAE - System Architecture Evolution
 EPS (Evolved Packet System)
LTE/SAE

4. What is 3GPP? 3GPP stands for 3rd Generation Partnership Project
It is a partnership of 6 regional SDOs (Standards Development Organizations)
Japan
USA
These SDOs take 3GPP specifications and transpose them to regional standards

5. Towards LTE

6. LTE Access Downlink: OFDM Uplink: SC-FDMA Diversity Beam-forming
LTE radio access
Downlink: OFDM
Uplink: SC-FDMA
Advanced antenna solutions
Diversity
Beam-forming
Multi-layer transmission (MIMO)
Spectrum flexibility
Flexible bandwidth
New and existing bands
Duplex flexibility: FDD and TDD
SC-FDMA
OFDMA TX
20 MHz
1.4 MHz

7. Terminology Updates
EPC = Evolved Packet core (earlier SAE=System Architecture Evolution).
e UTRAN = Evolved UTRAN (earlier LTERAN = Long Term Evolution).
EPS = Evolved Packet Systems including EPC and Terminals.

8. LTE Offer’s Performance and capacity DL 100 Mbps AND UL 50 Mbps
Simplicity
Flexible Bandwidths (5Mhz-20Mhz),
FDD and TDD
plug-and-play Devices
self-configuration Devices
self-optimization Devices

9. LTE (Long Term Evolution)
Radio Side (LTE – Long Term Evolution)
Improvements in spectral efficiency, user throughput, latency
Simplification of the radio network
Efficient support of packet based services
Network Side (SAE – System Architecture Evolution)
Improvement in latency, capacity, throughput
Simplification of the core network
Optimization for IP traffic and services
Simplified support and handover to non-3GPP access technologies

10. LTE Objectives Improve spectrum efficiency ( e.g. 2-4 x Rel6)
Reduced cost per bit
Improve spectrum efficiency ( e.g. 2-4 x Rel6)
Reduce cost of backhaul (transmission in UTRAN)
Increased service provisioning – more services at lower cost with better user experience
Focus on delivery of services utilising ”IP”
Reduce setup time and round trip time
Increase the support of QoS for the various types of services (e.g. Voice over IP)
Increase peak bit rate (e.g. above 100Mbps DL and above 50Mbps UL)
Allow for reasonable terminal power consumption

11. Evolution Path Architecture
The pay load is to be directed to a tunnel (eUTRAN)
Payload goes directly from the evolved node B to the Gateway
Control plane is directed at the Mobility management end.
LTE

12. LTE Architecture MME = Mobility Management EntityGb Iu
GERAN
UTRAN 3G 2G
LTE RAN
LTE
Non-3GPP
MME/ UPE
SGi
IP networks S3 S4
S5a S6 S7 S1 S2
”EVOLVED PACKET CORE”
MME = Mobility Management Entity
IASA = Inter-Access System Anchor
PCRF
HSS
SGSN
3GPP Anchor
SAE Anchor
S5b
IASA

13. Core Nodes of LTE
Serving GPRS Support Node (SGSN) - to provide connections for
GERAN (GSM Radio Access Network) and UTRAN Networks (UMTS Terrestrial Radio Access Network)
Serving Gateway - to terminate the interface toward the 3GPP radio-access networks
PDN Gateway - to control IP data services like routing, addressing, policy enforcing and providing access to non-3GPP access networks
Mobility Management Entity (MME) - to manage control plane context, authentication and authorization
3GPP anchor - to manage mobility for 2G/3G and LTE systems
SAE anchor - to manage mobility for non 3GPP RATs
Policy Control and Charging Rules Function (PCRF) - to manage Quality of Service (QoS) aspects

14. From 3GPP to LTE/SAE Non-3GPP access 2G 3G LTE IP networks
The PDN and Serving GW may be separate nodes in some scenarios (S5 in-between)
IP networks
Only PS Domain shown
HLR/HSS
SGi
PCRF Gr
S6a S7 S4
PDN GW Serving GW
SGSN
MME
S11
Non-3GPP access
S2a/b S3
S10 Gb
Iu CP
Iu UP
S1-MME
S1-U
BSC
RNC
Iur
eNodeB X2
BTS
Node B 2G 3G
LTE
PDN Gateway - to control IP data services like routing, addressing, policy enforcing and providing access to non-3GPP access networks

16. MME Functionality Roaming (S6a towards home HSS) Authentication
SAE CN Architecture
MME Functionality
SGi
MME
S1-MME
S1-U
S11 X2
S10
eNodeB S3 S4
SGSN
SAE GW
Roaming (S6a towards home HSS)
Authentication
SAE GW selection
Idle mode mobility handling
Tracking Area Update
Paging
Mobility handling of
inter-MME (pool) handover (triggered by eNodeB)
inter-RAT handover (triggered by eNodeB)
QoS “negotiation” with UE and eNodeB
Security
Ciphering and integrity protection of NAS signalling
Secure control signalling transport on S1 interface (unless taken care of by a SEG (Security Gateway))
O&M security (?)

17. SAE GW Functionality … SAE CN Architecture SAE GW PDN SAE GW:
SGi
MME
S1-MME
S1-U
S11 X2
S10
eNodeB S3 S4
SGSN
SAE GW
PDN SAE GW:
Policy Enforcement
Per-user based packet filtering (by e.g. deep packet inspection)
Charging Support
User plane anchor point for mobility between 3GPP accesses and non-3GPP accesses
routing of user data towards the S-GW
Security
O&M security (?)
Lawful Intercept
Serving SAE GW:
User plane anchor point for inter-eNB handover (within one pool)
User plane anchor point for inter-3GPP mobility
routing of user data towards the eNodeB
routing of user data towards the P-GW
routing of user data towards the SGSN (2G and 3G) or RNC (3G with “Direct Tunnel”)
Secure user data transport on S1 interface (unless taken care of by a SEG (Security Gateway))
The PDN SAE GW and the Serving SAE GW may be implemented in one physical node or separated physical nodes. …

18. Why LTE/SAE? Driving Factors for LTE/SAE
Introduction
Why LTE/SAE? Driving Factors for LTE/SAE
Ensuring that 3G is attractive in comparison with competing technologies (WiFi, WiMax, Flarion, …)
LTE/SAE architecture
Competing technologies looks simpler (fewer nodes)
OPEX (fewer node types to manage)
Significantly increased peak data rate
Competing technologies provide higher data rates
End-user experience
Reduced user plane latency
Necessary to achieve increased data rates
Significantly reduced control plane latency
Perception
Improved
Performance
(compared to WCDMA)

19. LTE – Performance Targets
Introduction
LTE – Performance Targets
High data rates
Downlink: >100 Mbps
Uplink: >50 Mbps
Cell-edge data rates 2-3 x HSPA Rel )
Low delay/latency
User plane RTT: Less than 10 ms ( RAN RTT )
Channel set-up: Less than 100 ms ( idle-to-active )
High spectral efficiency
Targeting 3 X HSPA Rel )
High performance for broadcast services
Spectrum flexibility
Operation in a wide-range of spectrum allocations
Wide range of Bandwidth
Support for FDD, Half-duplex FDD and TDD Modes
Cost-effective migration from current/future 3G systems
Focus on services from the packet-switched domain !

20. LTE/SAE Architecture

21. LTE/SAE Architecture
LTE/SAE Architecture (release 8) Functional changes compared to the current UMTS Architecture
Moving all RNC functions to the Node B …
…, SGSN CP functions to the MME, and GGSN functions to the SAE GW.
GGSN
P-GW S-GW
PDN GateWay
Serving GateWay
SGSN
MME
Mobility Management Entity
(not user plane
functions)
RNC
Node B / HSPA
eNodeB

22. LTE Architecture Evolved Packet Core
MME/UPE = Mobility Management Entity/User Plane Entity
eNB = eNodeB

23. Evolved Packet Switching Network Architecture
P-GW/S-GW
P-GW/S-GW
P-GW/S-GW
P-GW/S-GW E P C
Interfaces
MME
MME
MME
S11
S1-Cp X2 Gi
EUTRAN
LTE NODE B
LTE NODE B
LTE NODE B
LTE NODE B
LTE NODE B
Air Interface

24. LTE/SAE Architecture Main SAE interfaces (non-roaming case)
SAE CN Architecture
LTE/SAE Architecture Main SAE interfaces (non-roaming case)
IP networks
S1-MME: control plane protocol between eNodeB and MME
S1-U: user plane tunneling interface between eNodeB and Serving GW
S5: user plane tunneling interface between Serving GW and PDN GW
S8: user plane tunneling interface between Serving GW and PDN GW for roaming
S10: control plane interface between MME and MME
S11: control plane interface between MME and Serving GW.
S4: *) user plane tunneling interface between SGSN and PDN GW
S3: *) control plane interface between MME and SGSN.
O&M interfaces:
OSS-RC – MME
OSS-RC – SAE GW
OSS-RC
(SGi)
SGi
SAE GW
(in some use
cases only)
SAE GW
S5/S8 S4
SGSN
MME S3
S11
S10
S1-MME
S1-U
eNodeB X2
Note: Interfaces non-3GPP accesses not covered.

25. 2G Towards 3G Networks 2G 3G IP networks Only PS Domain shown HLR PCRFGr Gx Gn Gn
GGSN
SGSN Gb Iu
Policy Control and Charging Rules Function (PCRF) - to manage Quality of Service (QoS) aspects
BSC
RNC
Iur
BTS
Node B 2G 3G

26. HSPA (Higher Speed Packet Access)
IP networks
Only PS Domain shown
HLR/HSS Gi
PCRF Gr Gx Gn
GGSN
SGSN
Optimizing the 3G/HSPA payload plane for Broadband traffic Gb
Iu CP
Iu UP
10 Mb/s
BSC
RNC
Iur
BTS
Node B 2G 3G

27. A flat architecture for optimized performance and cost efficiency
LTE/SAE Architecture
From 3GPP Release 6 to LTE/SAE Improving performance with LTE/SAE; 3GPP Release 8
(Additions/changes in red.)
The PDN and Serving GW may be separate nodes in some scenarios (S5 in-between)
IP networks
Only PS Domain shown
HLR/HSS
SGi
PCRF Gr
S6a S7 S4
PDN GW Serving GW
SGSN
MME
S11
Non-3GPP access
S2a/b S3
S10 Gb
Iu CP
Iu UP
S1-MME
S1-U
BSC
RNC
Iur
eNodeB X2
BTS
Node B 2G 3G
LTE
A flat architecture for optimized performance and cost efficiency

28. LTE/SAE Architecture Product dimension
PA/DU Core & IMS
IP networks
HLR/HSS
HLR/HSS
SGi
”HLR/HSS”
PCRF
PCRF Gr
S6a
PDN GW
Serving GW
EPC S7 S4
PDN GW Serving GW
SGSN
SGSN
MME
MME
S11
S2a/b S3
”Mobility Server”
”Gateway”
S10 Gb
Iu CP
Iu UP
S1-MME
S1-U
PA/DU Radio
RBS
BSC
RNC
Iur
eNode B
eNodeB X2
BTS
Node B
Non-3GPP access 2G 3G
LTE
OSS

29. Comparison with Speed 40-100Mbps Fiber like speed on mobile
True high-speed mobile data
Full-motion HD video anywhere
Stream any content
Mobile peer2peer & Web 2.0 (Networking)
Triple play
EDGE
ADSL
EVDO-A
HSDPA
ADSL-2+
LTE
Fiber
Mbps

30. Comparison Cost
Spectral efficiency Better utilization of spectrum available
Low frequency, Advanced Receivers and Smart Antenna For improved coverage and reduced cost of ownership
Increased Capacity Much higher user and sector throughput for lower individual cost service delivery
Simpler RAN, IP Core & Centralized service delivery Fewer nodes & interfaces (Node- B/RNC/Gateway) One Network & IMS for all access technologies
Connect to legacy cores Existing network asset investment protection
3GPP/2 Market traction Economy of scale $
UMTS rel.99 voice call cost
10%
LTE VoIP cost*
Predicted LTE VoIP voice call cost* - Sound Partners Limited Research
3GPP subscribers
85% market share

31. Response Time 10-5msec latency Improved user experience
Highly Responsive Multimedia
Improved user experience
Fast VoIP call set-up
Instantaneous web pages
Streaming fast buffering
Online mobile gaming
EDGE
ADSL
EVDO-A
HSDPA
ADSL-2+
LTE
Fiber

32. LTE Time Line

33. Mobile broadband speed evolution
LTE Evolution
LTE
HSPA Evolution
Key Messages;
The technologies are here
Mobile radio access technologies are already well capable of delivering a broadband experience
A well coordinated standardization ensures mass adoption & economies of scale
This is a global effort
Users have taken HSPA to their hearts since HSPA delivers true broadband
Today almost 40 ops offering user speeds of 7 Mbps
In Geneva at the WRC (October-November 2007) we measured over 6 Mbps while driving in a car, and close to 1.4 Mbps uplink at the convention center – which is better than common fixed broadband
HSPA is already here and has a steady roadmap and is future proof
Suppliers like Ericsson are committed to future development
Ericsson will release 28 Mbps end of 2008 going for 42 Mbps during 2009
We have already demoed 160 Mbps on LTE where commercial products will be released 2009
LTE is a natural evolution of HSPA and will coexist with HSPA for a long time – HSPA will be the broadband wide area coverage and LTE will provide capacity and speeds in densely populated regions when needed
Additional Information about HSPA & LTE
Ericsson conducted the world's first demonstration of end-to-end HSPA Evolution technology with speeds of up to 42 Mbps at CTIA Wireless 2008, held in Las Vegas from April 1 to 3
Speeds of up to 42 Mbps represent the next phase in HSPA Evolution. These speeds are achieved by combining new higher order modulation technology (64QAM), together with 2x2 Multiple Input Multiple Output (MIMO) antenna technology. The first step of the HSPA evolution will be introduced during 2008
Different terminal classes are being defined for LTE and it looks like around 150 Mbps will be one of the supported classes. (In our press releases we have communicated 160 Mbps for LTE.) And, it does not stop there. In the future, HSPA can achieve higher bit rates ( Mbps downlink and Mbps uplink with multicarrier solutions). Also LTE has an impressive speed evolution - it will easily reach >300 Mbps with 20 MHz spectrum, and with 100 MHz spectrum well over 1 Gbps can be achieved.
Interoperability GSM/HSPA/LTE
Since these technologies are all from the same family, handover and interoperability between GSM, HSPA and LTE will be secured, the user will thus never be out of coverage.
HSPA
3G- R’99
Target
Peak rate
384 kbps
3.6 Mbps
7/14 Mbps
21/28/42 Mbps
~150 Mbps
1 Gbps
2002
2005
2007
2008/2009
2009
2013

34.
Thanks