ITU-
T
Workshop onon
Gap
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Nadi,Fiji,4.6July 2011JO,SunghoDeputySenior Manager,SKTe
LTEand NetworkEvolutionBridging theStandardizatiand InteractiveTraining Sess(Nadi,Fiji,4.6July2011)
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I.
SKT’s
Network
Strategy
and
LTE
○
Data
Traffic
Explosion
○
SKT’s
Network
Evolution
○
SKT’s
Network
Strategy
○
SKT’s
LTE
Deployment

.
Technology
Evolution
and
LTE
○
Technology
Evolution
○
LTE
Requirements
○
LTE
Network
Architecture
○
LTE
Advanced
Technology

.
Technical
Challenges
in
LTE
Deployment
○
Seamless
Operation
○
Heterogeneous
N/
W
&
Network
Automation(SON)
#
.
SKT’s
RAN Evolution:
SCAN (Smart
Cloud
Access
Network)
○
Cloud
Architecture
○
Smart
Network
Technologies

Ⅰ. SKT’s Network Strategy and LTE
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 Explosion

Voice Traffic Saturation
- CAGR for voice traffic increases by 5%
- Increasing rate diminishes after ‘09

Data Traffic Explosion
- CAGR for data traffic increases by 106%
- Data traffic explosion after ’09
Voice Traffic Trend Data Traffic Trend
2
9 times
(About 9 times increase from ’09 to ’10)
Voice (seconds/month, x 10
9
) Data (TB/month)
’06 ’07 ’08 ’09 ’10 ’06 ’07 ’08 ’09 ’10
Data Traffic Explosion is “World-wide Trend”

SKT’s Network Evolution
HSDPAWiBroHSUPAAlways“First”
SKT’sSKT’sNetworkNetworkEvolutionHistoryEvolutionHistoryHSPA+
First201120112007200720102010LTELTEHighqualityvoiceandComplementarysolutionforHotspotSKT’smobilenetworkhasevolvedbyrapidadoptioofnewtechnologies, andLTE-basedevolutionison-goingtooffertop-classservicescontinuouslyintheeraofdataexplosion.
FirstLTEinKoreaⅠⅠⅠⅠ.SKT’sNetworkStrategyandLTE319961996200020002003200320052005World-firstCDMACDMA20001XIS-95A/BWCDMA1xEV-DOS-DMBWorld-firstSatelliteDMB2G2G2.5G2.5G3G3G3.5G3.5G20062006World-firstCDMA20001x/EV-DOWorld-firstHandset-basedHSDPAWorld-first5.76MbpsHSUPAWorld-firstWCDMAR4FirstHSPA+inKorea20072007Medium-ratedataandnewservices(VideoCall,GlobalRoaming)
low-ratedataservices4GNetworkevolutionforhighdatarateservice4G4GSKT’sNetworkEvolutionHSDPAWiBroHSUPAAlways“First”
SKT’sSKT’sNetworkNetworkEvolutionHistoryEvolutionHistoryHSPA+
First201120112007200720102010LTELTEHighqualityvoiceandComplementarysolutionforHotspotSKT’smobilenetworkhasevolvedbyrapidadoptioofnewtechnologies, andLTE-basedevolutionison-goingtooffertop-classservicescontinuouslyintheeraofdataexplosion.
FirstLTEinKoreaⅠⅠⅠⅠ.SKT’sNetworkStrategyandLTE319961996200020002003200320052005World-firstCDMACDMA20001XIS-95A/BWCDMA1xEV-DOS-DMBWorld-firstSatelliteDMB2G2G2.5G2.5G3G3G3.5G3.5G20062006World-firstCDMA20001x/EV-DOWorld-firstHandset-basedHSDPAWorld-first5.76MbpsHSUPAWorld-firstWCDMAR4FirstHSPA+inKorea20072007Medium-ratedataandnewservices(VideoCall,GlobalRoaming)
low-ratedataservices4GNetworkevolutionforhighdatarateservice4G4G

SKT’s network portfolio efficiently copes with the data traffic explosion
by hierarchical multi-solution considering the traffic characteristics
SKT’s Network Strategy
. IS-95A/B: Nationwide
1X/IS-95A/B, DO: 92% Population
CDMA
1X/EVDO 1ISX-/9D5OA/BSeoul
JEJU
. 800MHz (BW 15MHz)
. 38% of total subscribers
SKT’s strategy for Mobile Broadband

Data Demand in Hot Zone
(Campus, Home, Office, etc.)

Cell Coverage Reduction for Higher Data Rate
 New Deployment Concept for Mobile Broadband
Data Traffic
Ⅰ. SKT’s Network Strategy and LTE
Seoul
JEJU
WCDMA
(HSPA)
WiBro
(Mobile
WiMax) Seoul
JEJU
‘06‘0‘097~’08
. Nationwide coverage
. 2.1GHz (BW 30MHz)
. 62% of total subscribers
. Metropolitan area (Seoul)
Hot zones in major cities
. 2.3GHz (BW 27MHz)
Voice Service Basic IP
Service
Multimedia
IP Service
Macro Micro Pico
WCDMA/
CDMA
Metropolitan Coverage
Nationwide Coverage
Hot Zone
Hot Spot DHaigtha -Dspeemeadn d
Optimal Network Portfolio
LTE
WiFi/
WiBro

LTE willbeusedfordealingwithhighdatatrafficinmetropolitanareaovernationwideWCDMA/HSPA(’11/’12), thenextendedtonationwidecoverage(‘13).
SKT’sLTEDeploymentSKT’sLTEDeploymentSKT’s LTE Deployment
SKT’sLTEPlan2011:FirstLTEserviceinKorea(’11,July)
withdatacardtypeterminal(Handsettypeterminalwillbeavailablein2ndhalfof‘11)
FirstLTEserviceinSeoul(‘11)
InJulyof2011, SKTwillprovidetheFirstLTEServiceinKorea.
ⅠⅠⅠⅠ.SKT’sNetworkStrategyandLTE5Network201120122013~
SeoulMajorcityNationwideDevelopment/Deployment2010Development/IOTData CardHandsetTerminalterminalwillbeavailablein2ndhalfof11)
2012:Coverageextensiontomajorcities2013:NationwidecoverageLTEcoverageextensiontoMajorCities(‘12)
LTEwillbeusedfordealingwithhighdatatrafficinmetropolitanareaovernationwideWCDMA/HSPA(’11/’12), thenextendedtonationwidecoverage(‘13).
SKT’sLTEDeploymentSKT’sLTEDeploymentSKT’s LTE Deployment
SKT’sLTEPlan2011:FirstLTEserviceinKorea(’11,July)
withdatacardtypeterminal(Handsettypeterminalwillbeavailablein2ndhalfof‘11)
FirstLTEserviceinSeoul(‘11)
InJulyof2011, SKTwillprovidetheFirstLTEServiceinKorea.
ⅠⅠⅠⅠ.SKT’sNetworkStrategyandLTE5Network201120122013~
SeoulMajorcityNationwideDevelopment/Deployment2010Development/IOTData CardHandsetTerminalterminalwillbeavailablein2ndhalfof11)
2012:Coverageextensiontomajorcities2013:NationwidecoverageLTEcoverageextensiontoMajorCities(‘12)

TechnologyEvolutionWCDMAHSDPAHSUPAHSPA+LTELTEAdvancedDL384kbpsUL64kbpsDL14MbpsUL64kbpsDL14MbpsUL5MbpsDL21MbpsUL5MbpsDL300MbpsUL150MbpsDL1GbpsUL500MbpsDL9.6kbpsUL9.6kbsGSM3GPP(Asynchronous)
IMT2000(3G)IMTAdvanced(4G)
CDMA-basedmobiletechnologyisevolvingtoOFDMA-basedtechnologyforhighdatarateservice. LTEwillprovide3~15timespeakdatarateascomparedtoHSPAⅡⅡⅡⅡ.TechnologyEvolutionandLTE6UL64kbpsUL64kbpsUL5MbpsUL5MbpsUL150MbpsUL500MbpsIS951xcdma2000EVDORev.ARev.BUMBDL14.4kbpsUL14.4kbpsDL153.6kbpsUL153.6kbpsDL2.4MbpsUL153kbpsDL3.2MkbpsUL1.8MbpsDL14.7MbpsUL5.4MbpsDL300MbpsUL150MbpsUL9.6kbs3GPP2(Synchronous)
CDMA(Voice-oriented):Connectivity,Circuit,SoftHandoverOFDMA(Data-oriented):WiderBandwidth,Packet,LessInterferenceOFDMA-basedtechnologyCDMA-basedtechnology“MobileBroadband”
TechnologyEvolutionWCDMAHSDPAHSUPAHSPA+LTELTEAdvancedDL384kbpsUL64kbpsDL14MbpsUL64kbpsDL14MbpsUL5MbpsDL21MbpsUL5MbpsDL300MbpsUL150MbpsDL1GbpsUL500MbpsDL9.6kbpsUL9.6kbsGSM3GPP(Asynchronous)
IMT2000(3G)IMTAdvanced(4G)
CDMA-basedmobiletechnologyisevolvingtoOFDMA-basedtechnologyforhighdatarateservice. LTEwillprovide3~15timespeakdatarateascomparedtoHSPAⅡⅡⅡⅡ.TechnologyEvolutionandLTE6UL64kbpsUL64kbpsUL5MbpsUL5MbpsUL150MbpsUL500MbpsIS951xcdma2000EVDORev.ARev.BUMBDL14.4kbpsUL14.4kbpsDL153.6kbpsUL153.6kbpsDL2.4MbpsUL153kbpsDL3.2MkbpsUL1.8MbpsDL14.7MbpsUL5.4MbpsDL300MbpsUL150MbpsUL9.6kbs3GPP2(Synchronous)
CDMA(Voice-oriented):Connectivity,Circuit,SoftHandoverOFDMA(Data-oriented):WiderBandwidth,Packet,LessInterferenceOFDMA-basedtechnologyCDMA-basedtechnology“MobileBroadband”

LTERequirementsⅡⅡⅡⅡ.TechnologyEvolutionandLTELTERequirementsⅡⅡⅡⅡ.TechnologyEvolutionandLTE
Peakdatarate100MbpsDL/50MbpsULwithin20MHzbandwidth(DL:5bps/Hz,UL:2.5bps/Hz,2x2MIMO default)
CapacityUpto200activeusersinacell(5MHz)
LatencyLessthan100msoncontrol-plane(IdletoActive)
Lessthan5msonuserplan(Unloadcondition,one-waytransmMobilityMobilityOptimizedfor0~ 15km/h,15~ 120km/hsupportedwithhSupportedupto350km/horevenupto500km/hHandoverHardHandoverSpectrumFlexibility:1.4,3,5,10,15,20MHzUserEquipmentSupportupto20MHzDuplexFDD,TDD
it
time
bw
UE
RAN
Edge
node)


igh
performance


7



LTE Network Architecture
MME
P-GW
S-GW
EPC
SAE
Ⅱ. Technology Evolution and LTE
8
eNB eNB
eNB eNB
X2
S1
EPC: Evolved Packet Core
MME: Mobility Management Entity
P-GW: Packet Data Network Gateway
S-GW: Serving Gateway
System Architecture Evolution
Long-Term Evolution
LTE

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 Advanced Technology
BSLTELTE AA TechnologyTechnology
CarrierAggregation(Upto100Mhz)RelayStationⅡⅡⅡⅡ.TechnologyEvolutionandLTE9AABSTransmitDiversityABSSpatial MultiplexingBContiguousCarrierAggregation Non-ContiguousCarrierAggregation
Relay forcoverageextensionRelay forcapacity increaseCoordinationBSBSMIMO(upto8×8)CoMP(BSCooperation)
LTEwillevolvetoLTE-A(Advanced)toenhancethecapacity, QoS, andN/Wflexibility.
SKTwillprovideLTE-Aservicein2013-14.
LTEAdvanced TechnologyBSLTELTE AA TechnologyTechnology
CarrierAggregation(Upto100Mhz)RelayStationⅡⅡⅡⅡ.TechnologyEvolutionandLTE9AABSTransmitDiversityABSSpatial MultiplexingBContiguousCarrierAggregation Non-ContiguousCarrierAggregation
Relay forcoverageextensionRelay forcapacity increaseCoordinationBSBSMIMO(upto8×8)CoMP(BSCooperation)

SeamlessOperationSeamlessoperationisoneofmostimportantissuesforLTEdeploymentinmulti-N/WenvironmentSeamlessHandoverSupportingcontinuityandmobilityofvoice/datacallsN/WSelectionSelectingservingN/Wbasedoncustomerprofiles,
operatorpolicyandterminaltypesN/WRedirectionRedirectingrequestedcallsintootherN/W(e.g.,CSFallback)
CSFllbkbd3GPPR9IMSbdVIPIII.TechnicalChallengesinLTEDeploymentWCDMALTEHotZone/NationwideNationwidem-VoIPorVoice H/OData H/Om-VoIP&
Hi-speedDataVoice &
Low-speedDataMulti-Mode Multi-BandTerminal
Redirection10SeamlessVoiceServiceCSFallbackbasedon3GPP-R9standard/IMS-basedmVoIPSeamlessOperationSeamlessoperationisoneofmostimportantissuesforLTEdeploymentinmulti-N/WenvironmentSeamlessHandoverSupportingcontinuityandmobilityofvoice/datacallsN/WSelectionSelectingservingN/Wbasedoncustomerprofiles,
operatorpolicyandterminaltypesN/WRedirectionRedirectingrequestedcallsintootherN/W(e.g.,CSFallback)
CSFllbkbd3GPPR9IMSbdVIPIII.TechnicalChallengesinLTEDeploymentWCDMALTEHotZone/NationwideNationwidem-VoIPorVoice H/OData H/Om-VoIP&
Hi-speedDataVoice &
Low-speedDataMulti-Mode Multi-BandTerminal
Redirection10SeamlessVoiceServiceCSFallbackbasedon3GPP-R9standard/IMS-basedmVoIP

Heterogeneous network maximizes the spatial
reuse gain, and deals with non-uniform traffic.
HetNet & SON
Heterogeneous Network
Conventional (Voice-oriented)
Plug and Play
Automated setup and
Self-Configuration
Network Automation (SON)
Network operation and management can be
automated by SON technologies.
III. Technical Challenges in LTE Deployment
11
HetNet (Data-oriented)
WiFi
Hot Zone
Biz. Cell
Relay
Macro Cell
Femto
Pico
Macro Cell
Repeater Pico Cell Weak Spots
(High Interference)
configuration
Auto Tune
Real-time network
optimization
Auto Repair
Fast, autonomous
failure mitigation
Self-Optimization Self-Healing
SON(Self Organizing Network)

“Cloud” Access Network “Smart” Access Network
Cloud-based digital
processing
. Centralized cloud DU
BS cooperation
in cloud architecture
. Interference SCAN management
Smart
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
IV. SKT’s RAN Evolution : SCAN
12
Network Cost Reduction
Eco-Friendly Technology
Capacity Improvement
Flexible Network Architecture
. BS virtualization by
real-time cloud processing
. Resource sharing (pooling)
and Cooperative Tx/Rx
. Load balancing & Traffic
optimization
Cloud Software Defined Radio
. Efficient maintenance Self Optimization

Cloud Architecture
Cloud DU DU-RU
Interface
Distributed RU
Core
 Evolution to Cloud Architecture
Unified DU/RU SReUpDaUrate DU/RU Centralized DURRUU Cloud DU RU
IV. SKT’s RAN Evolution : SCAN
13


Network
Centralized Digital Processing in Cloud DU
. First step: Separate DU/RU & Centralized DU
. Second step: BS virtualization by real-time cloud processing
Flexible Network Architecture
. Efficient resource management via virtualization
. Flexible network configuration using open platform

Smart Network Technology
Cloud DU DU-RU
Interface
Cooperative
Cell-edge
RU1 User
Monitoring of traffic and user QoS
 Evolution to Smart Network: Cloud-based BS cooperation, SDR, Self-optimization
IV. SKT’s RAN Evolution : SCAN
14


Central processing for BS cooperation
Cloud-based BS Cooperation : Network Capacity Enhancement
. Cooperative Radio Resource Management
. Multi-cell Transmission based on Multi-antenna Scheme
. Load Balancing and traffic optimization
SDR (Software Defined Radio) to support multi-technology
Transmission RU2

Thank You ThankYou
ThankYou