ITU-T Workshop on
Bridging the Standardization Gap
and Interactive Training Session
(Nadi, Fiji, 4 – 6 July 2011 )
LTE and Network Evolution
JO, Sungho
Deputy Senior Manager, SKTelecom
Nadi, Fiji, 4 – 6 July 2011
Contents
I. SKT’s Network Strategy and LTE
○ Data Traffic Explosion
○ SKT’s Network Strategy
Ⅱ. Technology Evolution and LTE
○ Technology Evolution
○ LTE Network Architecture
○ SKT’s Network Evolution
○ SKT’s LTE Deployment
○ LTE Requirements
○ LTE Advanced Technology
Ⅲ. Technical Challenges in LTE Deployment
○ Seamless Operation
○ Heterogeneous N/W & Network Automation(SON)
Ⅳ. SKT’s RAN Evolution: SCAN (Smart Cloud Access Network)
○ Cloud Architecture
○ Smart Network Technologies
1
Ⅰ. SKT’s Network Strategy and LTE
Data Traffic Explosion
In recent years, SKT’s analysis shows small increase in voice traffic,
but explosive increase in data traffic due to popularization of smart devices.
Data Traffic Trend
Voice Traffic Trend
○ Voice Traffic Saturation
○ Data Traffic Explosion
- CAGR for voice traffic increases by 5%
- CAGR for data traffic increases by 106%
- Increasing rate diminishes after ‘09
- Data traffic explosion after ’09
(About 9 times increase from ’09 to ’10)
Data (TB/month)
Voice (seconds/month, x 109)
9 times
’06
’07
’08
’09
’10
’06
’07
’08
’09
’10
Data Traffic Explosion is “World-wide Trend”
2
Ⅰ. SKT’s Network Strategy and LTE
SKT’s Network Evolution
SKT’s mobile network has evolved by rapid adoption of new technologies, and LTE-based
evolution is on-going to offer top-class services continuously in the era of data explosion.
Complementary solution
for Hotspot
SKT’s Network Evolution History
Always
“First”
1x EV-DO
CDMA2000
1X
IS-95A/B
1996
World-first
CDMA
2G
2000
World-first
CDMA 2000
1x/EV-DO
2.5G
HSPA+
WiBro
HSUPA
HSDPA
High quality voice and
low-rate data services
S-DMB
WCDMA
2003
World-first
WCDMA R4
3G
2005
World-first
Satellite DMB
LTE
2006
2007
2010
First
HSPA+ in Korea
World-first
5.76Mbps HSUPA
World-first
Handset-based
HSDPA
2011
First LTE
in Korea
4G Network
evolution
for high data
rate service
Medium-rate data and new services
(Video Call, Global Roaming)
3.5G
4G
3
Ⅰ. SKT’s Network Strategy and LTE
SKT’s Network Strategy
SKT’s network portfolio efficiently copes with the data traffic explosion
by hierarchical multi-solution considering the traffic characteristics
IS
IS--95A/B
1X/DO
IS-95A/B,
CDMA
1X/EVDO
• IS-95A/B: Nationwide
1X/DO: 92% Population
Seoul
• 800MHz (BW 15MHz)
• 38% of total subscribers
WCDMA
(HSPA)
WiBro
(Mobile
WiMax)
• Nationwide coverage
• 2.1GHz (BW 30MHz)
• 62% of total subscribers
‘06
‘07~’08
‘09 Seoul
Data Demand in Hot Zone
(Campus, Home, Office, etc.)
Cell Coverage Reduction for Higher Data Rate
New Deployment Concept for Mobile Broadband
Data Traffic
JEJU
Seoul
SKT’s strategy for Mobile Broadband
Basic IP
Service
Voice Service
Macro
Micro
Optimal Network Portfolio
Pico
High-speed
Data Demand
JEJU
• Metropolitan area (Seoul)
Hot zones in major cities
• 2.3GHz (BW 27MHz)
JEJU
Multimedia
IP Service
WiFi/
WiBro
LTE
WCDMA/
CDMA
Hot Spot
Hot Zone
Metropolitan Coverage
Nationwide Coverage
Ⅰ. SKT’s Network Strategy and LTE
SKT’s LTE Deployment
In July of 2011, SKT will provide the First LTE Service in Korea.
LTE will be used for dealing with high data traffic in metropolitan area
over nationwide WCDMA/HSPA (’11/’12), then extended to nationwide coverage (‘13).
SKT’s LTE Plan
2011: First LTE service in Korea (’11, July)
with data card type terminal (Handset type
terminal will be available in 2nd half of ‘11)
SKT’s LTE Deployment
First LTE service
in Seoul (‘11)
2012: Coverage extension to major cities
2013: Nationwide coverage
2010
2011
Seoul
Network Development
/Deployment
Terminal
Development
/IOT
2012
2013~
Major city
Nationwide
Data Card
Handset
LTE coverage extension
to Major Cities (‘12)
5
Ⅱ. Technology Evolution and LTE
Technology Evolution
CDMA-based mobile technology is evolving to OFDMA-based technology for high data
rate service. LTE will provide 3~15 times peak data rate as compared to HSPA
IMT Advanced (4G)
IMT2000 (3G)
3GPP
(Asynchronous)
3GPP2
(Synchronous)
GSM
DL 9.6kbps
UL 9.6kbps
IS95
DL 14.4kbps
UL 14.4kbps
WCDMA
HSDPA
HSUPA
HSPA+
DL 384kbps
DL 14Mbps
DL 14Mbps
DL 21Mbps
UL 64kbps
1x
cdma2000
DL 153.6kbps
UL 153.6kbps
UL 64kbps
EVDO
DL 2.4Mbps
UL 153kbps
CDMA-based technology
UL 5Mbps
UL 5Mbps
Rev.A
DL 3.2Mkbps
UL 1.8Mbps
LTE
DL 300Mbps
UL 150Mbps
Rev.B
UMB
DL 14.7Mbps
DL 300Mbps
UL 5.4Mbps
LTE
Advanced
DL 1Gbps
UL 500Mbps
UL 150Mbps
OFDMA-based technology
“Mobile Broadband”
CDMA(Voice-oriented): Connectivity, Circuit, Soft Handover
OFDMA(Data-oriented): Wider Bandwidth, Packet, Less Interference
6
Ⅱ. Technology Evolution and LTE
LTE Requirements
Peak data rate
100 Mbps DL/ 50 Mbps UL within 20 MHz bandwidth
(DL : 5bps/Hz, UL : 2.5bps/Hz, 2x2 MIMO default)
Capacity
Up to 200 active users in a cell (5 MHz)
Latency
Less than 100 ms on control-plane(Idle to Active)
Less than 5ms on user plan(Unload condition, one-way transmit time bw UE ~ RAN Edge node)
Mobility
Optimized for 0 ~ 15 km/h, 15 ~ 120 km/h supported with high performance
Supported up to 350 km/h or even up to 500 km/h
Handover
Hard Handover
Spectrum
Flexibility: 1.4 , 3, 5, 10, 15, 20 MHz
User Equipment
Support up to 20 MHz
Duplex
FDD, TDD
7
Ⅱ. Technology Evolution and LTE
LTE Network Architecture
EPC
P-GW
MME
S-GW
SAE
System Architecture Evolution
S1
Long-Term Evolution
LTE
eNB
eNB
eNB
X2
eNB
EPC: Evolved Packet Core
MME: Mobility Management Entity
P-GW: Packet Data Network Gateway
S-GW: Serving Gateway
8
Ⅱ. Technology Evolution and LTE
LTE-Advanced Technology
LTE will evolve to LTE-A(Advanced) to enhance the capacity, QoS, and N/W flexibility.
SKT will provide LTE-A service in 2013-14.
LTE--A Technology
LTE
Carrier Aggregation
Relay Station
(Up to 100Mhz)
BS
Non-Contiguous
Carrier Aggregation
Contiguous
Carrier Aggregation
Relay for capacity increase
CoMP(BS Cooperation)
MIMO (up to 8×8)
BS
B
A
Spatial Multiplexing
BS
Relay for coverage
extension
A
A
Transmit Diversity
BS
BS
Coordination
9
III. Technical Challenges in LTE Deployment
Seamless Operation
Seamless operation is one of most important issues for LTE deployment
in multi-N/W environment
N/W Selection
N/W Redirection
Seamless Handover
Seamless Voice Service
Selecting serving N/W based on customer profiles,
operator policy and terminal types
Redirecting requested calls into other N/W (e.g., CS Fallback)
Supporting continuity and mobility of voice/data calls
CS Fallback based on 3GPP-R9 standard/ IMS-based mVoIP
m-VoIP or Voice H/O
Hot Zone/Nationwide
Nationwide
LTE
Redirection
WCDMA
Data H/O
m-VoIP &
Hi-speed Data
Voice &
Low-speed Data
Multi-Mode Multi-Band Terminal
10
III. Technical Challenges in LTE Deployment
Heterogeneous Network
Heterogeneous network maximizes the spatial
reuse gain, and deals with non-uniform traffic.
HetNet & SON
Network Automation (SON)
Network operation and management can be
automated by SON technologies.
Conventional (Voice-oriented)
Self-Configuration
Plug and Play
Macro Cell
Repeater
Pico Cell
HetNet (Data-oriented)
Pico
WiFi
Weak Spots
(High Interference)
Macro Cell
Relay
Femto
Biz. Cell
Hot Zone
Automated setup and
configuration
SON(Self Organizing Network)
Self-Optimization
Auto Tune
Real-time network
optimization
Self-Healing
Auto Repair
Fast, autonomous
failure mitigation
11
IV. SKT’s RAN Evolution : SCAN
Smart Cloud Access Network
SKT’s RAN(Radio Access Network) architecture is evolving to “SCAN”
in order to reduce the network cost and enhance the capacity
“Cloud” Access Network
Cloud-based digital
processing
• Centralized cloud DU
• BS virtualization by
real-time cloud processing
• Resource sharing (pooling)
• Efficient maintenance
Smart
SCAN
Cloud
Network Cost Reduction
Flexible Network Architecture
“Smart” Access Network
BS cooperation
in cloud architecture
• Interference management
and Cooperative Tx/Rx
• Load balancing & Traffic
optimization
Software Defined Radio
Self Optimization
Capacity Improvement
EcoEco-Friendly Technology
12
IV. SKT’s RAN Evolution : SCAN
Evolution to Cloud Architecture
Unified DU/RU
Cloud Architecture
Separate DU/RU
Centralized DU RU
RU
Cloud DU
RU
RU
DU
Cloud DU
DU-RU
Interface
Distributed RU
Core
Network
Centralized Digital Processing in Cloud DU
Flexible Network Architecture
• First step: Separate DU/RU & Centralized DU
• Second step: BS virtualization by real-time cloud processing
• Efficient resource management via virtualization
• Flexible network configuration using open platform
13
IV. SKT’s RAN Evolution : SCAN
Smart Network Technology
Evolution to Smart Network: Cloud-based BS cooperation, SDR, Self-optimization
Cloud DU
Monitoring of traffic and user QoS
DU-RU
Interface
RU1
Cooperative
Transmission
Cell-edge
User
RU2
Central processing for BS cooperation
Cloud-based BS Cooperation : Network Capacity Enhancement
SDR (Software Defined Radio) to support multi-technology
• Cooperative Radio Resource Management
• Multi-cell Transmission based on Multi-antenna Scheme
• Load Balancing and traffic optimization
14
Thank You
15