IT R&D Global Leader Network Technologies for Mobile Research Activites of ETRI IMT_Advanced (3GPP LTE Based) 2008. 6.24. 송평중 pjsong@etri.re.kr -1-
Topics I. 3.9G 네트워크기술의핫이슈 네트웍컨버젼스를위한 emobility 방. 통융합을위한 embms 유. 무선통합을위한 Home Cell II. 4G 네트워크핵심요소기술전망 IMT-Advanced Issues 4G 네트워크핵심요소기술 III. Concluding Remarks -2-
Terminology Terminology IMT-Advanced = 4G = SB3G (Systems Beyond IMT-2000) = B3G LTE : Long-Term Evolution (RAN part, 3.9G) SAE : System Architecture Evolution (CN part) EPS : Evolved Packet Service (LTE + SAE) enodeb : evolved NodeB MME : Mobility Management Entity S-GW or P-GW : Serving GateWay or PDN GateWay EPC : Evolved Packet Core (for Core Network) EUTRAN : Evolved UTRAN (for Access Network) 3GPP : 3 rd Generation Partnership Project UE : User Equipment -3-
1. 3.9G 네트워크기술의핫이슈 (3GPP LTE Tech. for NW Convergence) 네트웍컨버젼스를위한 emobility 방. 통융합을위한 embms 유. 무선통합을위한 Home Cell
COST 절감을위한 Flat Architecture 3GPP Long-Term Evolution. VoD Ftp Server Server EPC IP Phone EUTRAN Public Internet t Web Server Cost-saving factors: AN -> RNC 제거, CN -> Circuit 장비제거 UE Vision : Future-oriented radio access system toward IMT- Advanced (4G) Architecture : Flat-arch. & Open interfaces (S1/X2/Uu/O&M) with Inter-RAT Mobility Technology : Full-IP based cost- effective system thru optimized radio and simplified network Service : True quadruple play (IP voice, high-speed interactive (gaming), large data transfer, mobile IP-TV) Standard : Draft in 2007 (Rel.8), and dcommercial product after 2010! -5-
네트웍컨버젼스를위한 emobility How to achieve network convergence in heterogeneous env.? Inter-RAT mobility! => Always best accessible framework thru NW convergence!. HPLMN WCDMA 3GPP Access LTE S6a Serving Gateway Interworking architecture Optimized HO procedure HSS (1) Pre-registration Wx* (2) HO Execution PCRF 타겟시스템선택알고 S7c Rx+ S7 리즘 : ANDSF Operator's IP SGi Services PDN 인터워킹방법 : No (e.g. IMS, PSS Gateway etc ) translator ( 터널링 & S5 PMIP S2b S6c 인캡술레이션 ) S7b Wm* (3) HO Completion S2a epdg Wn* 3GPP AAA Server Non-3GPP Networks Trusted Non-3GPP IP Access Mobile WiMAX S7a Wu* Untrusted Non-3GPP IP Access UE WLAN Wa* Ta* Inter-RAT mobility => S-GW/P-GW를통한이종액세스네트워크간컨버젼스구현기술! -6-
네트웍컨버젼스를위한 emobility Inter-RAT mobility (LTE->WCDMA) Public Internet HO use cases LTE 셀의트래픽폭주 LTE 셀의신호간섭증대 LTE 셀의 Partial deployment PDN-GW LTE (RAT-A ) WCDMA (RAT-B ) (0) Current Path 13) PATH SW (12) UPDATE BEARER REQ (13) UPDATE LOCATION, etc Serving -GW PACKET FORWARDING (enb NB via SGW) SGSN MME (6) FWD RELOCATION RESP (4) FWD RELOCATION REQ (11 ) FWD RELOCATION COMPLETE HO procedures (3) HO REQUIRED HO Preparation Ph.(1-6) HO Execution (7-9) RRM HO Completion (10-13) (2) Target Selection (7) HO CMD E-UTRAN enb (11 ) RELEASE RESOURCE (5/5a) RELOCATION REQUEST/ACK UTRAN (8) HO COMMAND (10) HO CONFIRM (1) MEASUREMENT Handover (11) RELOCATION COMPLETE RNC NB (9/9a) Target Access : (RF/BB SW ) -7-
네트웍컨버젼스를위한 emobility HO time & Interruption time (Inter-RAT : LTE WCDMA, 추정치 ) Total HO time : 208ms ( ~ ), where only up to 10(6) data packets are forwarded HO interruption time : max 140 ms for non rt-traffic Downlink data flow lat tency profile e #46 #47 #4 #49 #50 #51 #52 #53 #54 #55 #56 #57 #58 #59 #60 #61 #62 ~ 140 ms agw enodeb 4 packets (#52-#55) cannot be transmitted to the UE before completion of synchronization with target cell #46 #47 #48 #49 #50 #51 #52 #56 #57#58 #59 #60 to # 55 RN C UE 208 ms time [s] -8-140ms! => Seamless handover! "Measurement Report" sent by UE to source enodeb / RNC "HO Command" sent by source enodeb / RNC to UE "HO Complete" received by target RNC / enodeb from UE "Path Switch" performed at agw Source : 3GPP
방. 통융합을위한 embms Definition of MBSFN SFN concept is introduced for efficient MBMS operations An MBSFN area consists of a group of tightly synchronized cells where all cells are using the same radio resources in the same frequency band to synchronously transmit identical MBMS data Definition of MBMS area MBSFN : Multicast/Broadcast Single-Frequency Networking -9-
방. 통융합을위한 embms embms functions MBMS GW (~EPC) SYNC protocol to each enb MBMS Session Control Signaling (Session start/stop) towards the enb MCE (Multicast Cordination Entity) MBMS service distribution (MCE) MBMS Tx cordi enodeb MBMS scheduling MBMS Tx & Rx MBMS Radio bearer control Further issues RRM : Efficient resource management for unicast c MME~ Logical Architecture for embms PGW Contents Provider BM-SC ~agw -10-
방. 통융합을위한 embms MBMS Deployment Scenarios Mixed Carrier : 통신과 M-IPTV 동시서비스 Transmission Carrier Radio Scenario Comments (SFN ) (Feq. layer) Bearer S-D Single-Cell Dedicatedcarrier -Single-cell (No SFN operation) p-t-m Specific-cell에서 only MBMS 단일전송 (SFN) (MBMS only). Soft combining & Synch tx 모두가능안함 1 -Dedicated-carrier (belong to Freq-layer) M-M Multi-Cell (No SFN) Mixed- Carrier (MBMS + 2 Voice/Data) p-t-m * RB (p-t-p) p) : not used MBMS p-t-m Transmission scenarios in E-UTRAN. MBMS 서비스만가능 (unicast data 전송은불가 ) Unicast & MBMS mixed transfer in Multi-cell -Multi-cell (SFN operation). Soft combining & Synch tx available - Mixed-carrier. MBMS/Unicast. Dual Receiver (Mobile TV & VoIP) Soft combinig at the cell boundary 2 1-11-
유. 무선통합을위한 Home-cell 3G Home enb scenario in 3GPP HIGHER NETWORK NODE C LTE MACRO CELL A D B HeNB and HeNB GW scenario (tbd) OTHER 3GPP SYSTEM Basic concept of Home enb 차세대유. 무선통합서비스수익모델! Source : 3GPP Home/Office/Campus 등에서사용가능한초소형기지국 이동성 (Mobility), 고품질통신서비스 (QoS), 강력한통신보안 (Security), Closed Subscriber Group (CSG), SON 및홈게이트웨이 (trafficconcentration) 등이주요기술 Benefit : Indoor-cell, Singlemodem, and Full cellcapacity -12-
유. 무선통합을위한 Home-cell Interference scenarios (UTRAN) Spectrum arrangement for EUTRAN Deployment config. (Partial co-channel) HNB Macro BCH SCH freq No overlapping of central 6 RBs between HENB Macro NB => UE 는 home-cell 에서 macro enb 의신호간섭없이 BCH & SCH 수신 => Frequency hopping and Frequency dependent scheduling Main Issues of H-Cell ((e)/utran) Architecture for 3G HNB Inbound /Outbound mobility CSG white-list configuration HNB/UE registration HNBAP protocol (HNB-HNBGW) Function split of HNB-3G HNB-GW HNB-GW Discovery HNB (auto)-configuration (SON) 표준화 : SA1/2/3/5, RAN2/3/4, CT1 Source : 3GPP -13-
2. IMT-Advanced Issues
LTE vs. LTE-Advanced LTE : LTE-Advanced : IMT-Advanced Future Advanced Capabilities for LTE-Advanced Physical-layer l ITU-R RREQ TREQ LTE (Essential Capabilities) Advanced Capabilities for Network Physicaldomain Networkdomain -15-
LTE-Advanced Requirements 항목세부항목 LTE LTE-Advanced 1. Capability (max value) 2. System performance (max value) Peak Data Rate (system target view) Latency (C-plane) (w/o S1 interface & unloaded) DL : 300Mbps (4x4, 64QAM) UL : 75Mbps (1x2, 16QAM) Idle-Active : 100ms Dormant(DRX)-Act : 50ms DL : 1Gbps UL : 500Mbps Idle-Active : 50ms Dormant(DRX)-Active : 10ms Latency (U-plane) 10ms (one-way at IP layer) Less than LTE C-plane Capacity 200 active users /5 MHz 300 active users /5 MHz Peak spectrum efficiency DL : 15 bps/hz DL : 30 bps/hz (8x8) (error-free, single UE) UL : 3.75 bps/hz UL : 15 bps/hz (4x4) Average spectrum efficiency (higher priority) DL : 3~4 * HSDPA UL : 2~3 * HSDPA DL : 2.6 (4x2) or 3.7 (4x4) UL : 2.0 (2x4) Cell edge spectrum efficiency DL : 3~4 * HSDPA DL : 0.09 (4x2) or 0.12 (4x4) (5% point of CDF normalized) UL : 2~3 * HSDPA UL : 0.07 (2x4) Mobility 350km/h 350km/h (up to 500km/h) Coverage ~5Km : Best throughput.. LTE are applicable Further Enhanced MBMS Reuse of L1,Soft-combining Better than LTE Network synchronization Spectrum flexibility 시각동기없이성능달성 성능월등하면동기제공 1.4, 3, 5, 10, 15 and 20MHz BW. LTE are applicable 450MHz~4.99GHz내의 6 bands Consecutive spectrum for wider BW than 20MHz Src : 3GPP TR36.913-16-
LTE-Advanced Requirements 항목세부항목 LTE LTE-Advanced 3. Deployment Deployment Scenarios Co-existence & interworking No backward compatible For underground 3GPP Inter-RAT HO Network Sharing S1-flexiblity S1-flexiblity Backward compatible with LTE Indoor enb and HNB in aeutran Inter-RAT interworking capability (HO) => At least same as LTE => Req t : Inter-RAT HO (LTEA-LTE) = Intra-LTEA HO 4. EUTRAN arch. Cost-eff. & flat arch. Based on E-UTRAN Architecture Enhanced local area access 5. RRM Low/high-level RRM end-to-end QoS. LTE applicable 6. Complexity Adv EUTRA complex. multi-rat mode, Opt 수 LTE applicable 7. Cost Infra. & terminal Size, weight, battery Low cost & power efficiency Backhauling S1/X2/RNL optimized Minimized cost per bit SON Mainly for enodeb Special care for NW sharing & HeNB enode B implementation No relay Cost eff. and flexibility for multi-vendor Remote radio units and open interfaces All Interface Open Interoperability for multi-vendor 8. Service Service-related rela ed High-speed Mobile LTE applicable requirements Service w/ small latency To be added (4G specific : U/B/C?) Src : 3GPP TR36.913-17-
IMT-Advanced Issues 항목세부기술타겟사례 1. New deployment scenarios Relay/ Home-cell의 Architecture aeutran arch. for local area access 효과적수용구조 (cost) 2. L1 Band aggregation, advanced antenna, CR.. PDR, spectral efficiency, latency,capacity 4G 대역확보와스펙트럼효율추가개선등 3. L2 & L3 Advanced MAC scheduling, optim-harq HARQ, L2 스케쥴링과 L3 시그 - Signaling delay optimization (half) 널링개선 4. RRM Common & cooperative RRM Optimized inter-system operation 5. Mobility Seamless Inter-RAT mobility FMC, group mobility 6. ICIM Centralized & adaptive ICI management Multi-layering layering approach (Phy/MAC/RRM) 7. Small Base Stations Multi-hop relay Home-cell 셀간간섭제어, 셀간 / 시스템간부하제어 심리스핸드오버, 그룹모빌리티 셀간효과적간섭제어 커패시티 / 커버리지개선 Indoor, Single modem 8. SON Autonomous self-configuration& optimiz. 기지국운용최적화및 ALU (plug & play) Standardized multi-vendor SON 운용비용감소 9. Applications ETWS, wireless IPTV, 3D virtual reality.. Personal IPTV, CAT, medical IT, D2D comm., Cooperative Tx, CO2 emission, etc 새로운비지모델 - - DCM - Ericsson, DCM Nortel NEC/ NICT 10. Others Further optimization of LTE (L1~L3) LTE 기술의최적화 (Sig.) -18-
Slides title here 3. LTE-Advanced 네트워크의 핵심요소기술 * Ref : 3GPP LTE, and LTE-Adv W/S (Shenzhen, Apr, 2008)* Flexible and Scalable Network Architecture Cooperative RRM, Network Sharing Optimized Multi-RAT Mobility (Advanced) ICI Management Nomadic & Local Access Base Station (MHR) Autonomous Self Organizing Network Applications Examples
< Ref > Key Tech. in PHY-layer How to utilize spectrum resource in more flexible and efficient? WINNER project approach ; Spectrum, MIMO, Relay. Src : WINNER -20-
(1) Flexible & Scalable Architecture How to achieve flexible and scalable access network architecture? => Small base station! A possible architecture of LTE based LTE-A RNC Public Internet HSS PCRF CRRM Unified IP 3G+ (HSPA Evol) HENB AGW S1+ flex MHR 4G (LTE Based) MHR : Multi-Hop Relay HENB : Home enodeb ENB+ : Advanced enodeb (ENB + SGW) AGW : Access GW (MME+PGW) Xr : Relay-link interface (MHR-ENB) Ur : Radio-link interfcae(mhr-ue) ENB+ Unified IP MHR UE (multi-rat) Unified IP ACR Non-3GPP (e.g. mwimax) Some architecture issues EUTRAN to be enhanced with small base stations (cell coverage & user throughput, ho-delay) New interfaces (R1, R2) Multi-operator network sharing (S1+ flex) Unified interface, and common server (C-RRM) as a network convergence-driver Multi-RAT terminal (Multi- mode, SDR, CR ), etc -21-
(1) Flexible & Scalable Architecture A possible architecture for LTE-Adv -22-
(2) Cooperative RRM Cooperative RRM for heterogeneous environments! Current : Distributed RRM => Future : Cooperative RRM Concept. of Cooperative RRM (e.g, E2E QoS) RAN-A CRRM Functions. of RRM (e.g, LTE) RAN-B Cooperative RRM For efficient Always best access under heterogeneous access networks, Hybrid-type RRM is expected : Cooperative RRM in CN, and Distributed RRM in AN R&D issues of high-level RRM Efficient resource management QoS Control, Load balancing System cap. improvement, etc. R&D issues of low-level RRM Dynamic resource allocation Link adaptation Packet scheduling Multi-user diversity ICIC, etc -23-
(2) CRRM - Load Balancing Load balancing mechanism (E.g. handover optimization in LTE) Traffic high density Cell shrinking thru HO parameter optimization Neighbor list optimization, and coverage/capacity control Problem : Increase of signaling load due to additional interactions Load is balanced between Cell A and Cell C Blocking rate as a function of mobile arrival rate (Copyright John Wiley & Sons Ltd * Source : 3GPP -24-
(3) Network Sharing for MVNO Radio access network sharing configuration The cost for building the radio access network can be shared by the multicore network operators, thereby reducing the total investments. Advanced S1-flexiblity is expected for more flexible network sharing scheme in LTE-Adv RAN -sharing configuration Impact on interfac es Impact on S1 Impact on X2 Impact on S1/X2 interfaces Handovers (LTE to 3G) An enodeb to be attached to multiple MMEs/S-GW that can be operated by different core network operators. This would reuse the S1-flex functionality for pooling of core network resources in non-shared networks. X2 interface is internal between enodebs in the shared network, no impacts are foreseen on the X2 interface -25-
(4) Optimized Multi-RAT Mobility How to implement more optimized network convergence?. Non-3GPP mobility with optimized handover procedure! Inter-RAT Vertical Handover HSS R-Table CN Public Internet IP Back-bone AGW PCRF PBRM S101 Optimized HO procedure HO Preparation(Pre-registration) HO Execution 타겟시스템선택알고리즘 : NW controlled ANDSF, PB-RRM 인터워킹방법 : 터널링 & 인캡술레이션 (No translator) HO Completion Ex: PMIP에의한 pathswitching PB-RRM A MME enb 3GPP (source) Handover (AB) UE ModeA ModeB ACR/ePDG B RAS/AP 3GPP2/WiBro (target) t) -26-
(5) ICI Management How to coordinate inter-cell interference in LTE? DL & UL resources in a multi-cell environment are coordinated to avoid intercell interference by determining which radio resources are scheduled for restriction * Initial setting 1) UE measure and report to serving! 2) enodeb Serving Measurements request status (examples): of neighbor 1 & 2 DL total transmitted carrier power 3) Neighbor 1&2 measure and report DL resource block transmitted carrier power 4) Serving DL/UL total request resource Mute block usage for co- interference, DL/UL resource load block imbalances activity A high level procedure for ICIC Serving 4 3 Neighbor 1 Neighbor 2 1 2 5 1. status information (autonomous resources, resources for disposition) 2. Mute Request, Mute Request Accept ( Please mute/reduce power on Chunk-25, Ref: R1-060586, R1-050763 ) UE Measurements (examples): UE buffer status UE power headroom Transport channel BLER CQI * Source : 3GPP -27-
(5) ICI Management Central unit for interference Remote radio equipment for coordination (Ericsson) inter-cell orth.(ntt DCM) Tight scheduling coordination of transmission/reception i ti at geographically separated points Central Unit (enb) handling large number of cells => No impact on E-UTRAN architecture Autonomous control : ICIC among in dependent d cells using control signa ls via backhaul (faster than FFR) Centralized control : ICI manageme nt using scheduling at Centralized ICI controller (enb) connected to RREs via optical fibers Src : LTEA Workshop (Ericcson/DCM) -28-
(6) Multi-hop Relaying How to improve coverage extension & cell-edge performance? A solution : Relay station! Back-haul 사용없이기지국신속건설 (Wireless connection). L1 Relay (repeater) : 증폭송신 / delay 무시 L2 Relay : 데이터복원 / 증폭송신 Layer 3 relay (small BS) : Equivalent to enb with selfbackhuling -29- A model of multi-hop relay MR-BS : Multi-hop Relay Base Station to manage RSs R S : Relay Station MS : Mobile Station Key advantages of Relay S. To enable cost-effective and seamless ubiquitous service by extending carrier network deployment into indoor space Functionality MR-BS : Management of RSs RS : Fixed type or mobile type Type of Relay Station Src : ITU Workshop (Nortel)
(7) Autonomous Self Organizing NW Basic Operation of Self-Organizing Network (SON) 시스템운용의안정화, 최적화및운용비용의감소 ( 사업자주도 ) Basic operation of SON Basic operation. A. Self-configuration thru downloading B. Self-optimization thru measurement Basic functions Issues Self-configuring Self-optimizing Self-monitoring Self-Healing : automatic fault detection and recovering Self-knowledge : autonomic surrounding detection and decision making Support multi-vendor SON : standard issues (protocols, ANR, PhyCId, and S1/X2) Src : LTEA Workshop (ALU) -30-
(7) Autonomous SON Example Reduction of OPEX with SON server OPEX can be minimized by reducing manual operations => by SON Both enhanced enb and UE reporting allows always-on RAN monitoring for proactive reactions to user experiences. Self Deployable Cell Always on RAN performance monitoring based on enb and UE reporting. O&M Measurement data SON Server Configuration profiles Automatic Common Channel Power Control Very low throughput reporting with location info HO failure reporting with location info Src : LTE-A WS (NEC) -31-
(8) Applications Energy efficient BS Shutdown management of Radio Access Networks CO2 emission causing global warming will be 1.6 times all over the world in 2030 (compared to 2005). LTE-Advanced should consider the reduction of CO2 emission due to RAN. Partial or complete enb power down during low load, e.g. at night => Only Master BS active at night Master BS Automatic partial or complete power down Src : LTE-A WS (NEC) -32-
(9) Applications - Cooperative Transmission Simultaneous multiple-transmission of multi-media services 각서비스특성 (QoS) 과각 RAT (Radio Access Technology) 의트래픽부하를고려한최적의 access network 선택및이 access network을통한동시다중전송. Cooperative Transmission Tech. Techniques required for usercentric efficiency from the standpoint of a converged network with multi-rats Common & Generic RRM required for Cooperative Transmission Src : IST project (TeliaSonera) Key issues Vertical handover tech. with route different traffic flows through different interfaces in parallel Optimized network loadbalancing -33-
(9) Applications - Medical IT Medical IT is one of the killer applications in next IT direction!. Medical application system using wireless tech. Medical application system Medical IT! IP based medical system = Bio-sensor + Wireless Body Area Network + Medical servers + Ubiquitous network infra Potential patients, % of 60 years or older 2050 in the world : about 20% Real-time monitoring system on medical treatments Interworking for Medical IT! 셀룰러와 BAN간연동기능필요 Src : (NICT-ETRI Workshop, 2007), Ryuji Kohno s, YNU/NICT/Medical ICT Consortium -34-
(9) Applications - Medical IT. Medical IT is one of the killer applications in next IT trends 소요기술 : UWB, Array Antenna, SDR, Positioning, and Informatics, etc Wireless devices /Bio-sensor for medical appl. Wireless communication technologies to support medical treatments and diagnosis Wireless technology required in BAN Countermeasure techniques (equalization, diversity, coding, antenna, etc) Positioning & Ranging=Position recognition (radar, navigation) Awareness & Control= Inside-body sensing (sensor, adaptive control) Information security=abusiveness protection*privacy (charge info, privacy protection) Spread Spectrum & UWB Technology Array Antenna Technology Reconfigure = Changing operator. Fault searching (changing to new tech., fault maintenance) Antenna (securing of good wireless commu. environment) SDR Technology Lower power consumption = Long operable time (implementation of low power consumption) Src : (NICT-ETRI Workshop, 2007), Ryuji Kohno s, YNU/NICT/Medical ICT Consortium -35-
Event.1A (Power-On: Attach) Event.2A (M.O) Idle-Active (100ms/ 50ms) (10) Signaling Aspects (Basic set-up phase in LTE : Attach + M.O) UE Option Procedure only for Attach (NW) Cell Searching SIB Acquisition Idle Random Access Preamble Random Access Response RRC Connection Request RRC Connection Setup SRB1 assigned (Attach Request/ Service Request) RRC Connection Setup Complete ENB (1) Identification (2) Authentication (3) Update of Loc How to optimize it? - Setup latency (50ms), - Multi-layered overhead, etc Initial UE Message (4) Create of default DRB & IP MME/ S-GW RRC - Security Mode Command (KEY) (Attach Accept/ Service Accept) RRC Connection Reconfiguration RRC Connection Reconfiguration Complete Initial Context Setup Request (KEY) Initial Context Setup Complete Connected (or Attached) After releasing all RRC-Connections Yes (in idle) Inactivity Time-out? No (still alive) Event 1B Event.1B (Old-DRB, New-DRB) SRB 1/2+default DRB assigned (Transfer mode on def DRB : SIP/Bgrd) SAE Bearer Setup Request RRC Connection Reconfiguration (add-drb) RRC Connection Reconfiguration Complete SAE Bearer Setup Response SRB 1/2+default DRB + additional DRB assigned (Transfer mode) Yes (in idle) Connected Inactivity Time-out? No (still alive) Event 1B -36-
Concluding Remarks A model of LTE-Advanced network (LTE based) LTE-Advanced => Multi RATs + Common All IP network + (WSN) with support of vertical mobility PSTN/ PSDN Operator IP Services (e.g. IMS, AF, etc) SGi Common CN in NGN Rx+ PCRF S7 P-GW Public Internet P-GW IP-BB P-GW CCS7 BSC SGSN S4 RNC HLR/HSS S3 S6 S1 AP (SCTP) S-GW S11 MME S1-U (GTP-U) IP Trans. NW S2a ACR BTS NodeB E-NB E-NB+ E-NB+ RAS LTE-Uu (Radio ) MHR MHR 2G (e.g, GERAN) 3G (e.g,utran, HSPA+) UE (MMMB) * LTE (initial version) => LTE-Advanced (adv. version of LTE) 3G+ (e.g, LTE) HENB HENB 4G (LTE Based) Non-3GPP (e.g. mwimax) -37-
Concluding Remarks LTE and LTE-A LTE-Advanced = A superset of LTE LTE-A is evolution of LTE with the following key issues! New architecture ARCH : Flexible and Scalable Architecture (Local area access) New technologies/features RF : Wider BW, and Band aggregation of fragmented spectrum PHY : Advanced MIMO (corporate MIMO, network MIMO, UL-SU-MIMO) BS : Multi-hop relay, (Advanced Home-cell) Further improvements ICI : Advanced Inter-cell interference management SON : Self Organizing Network MBMS : Advanced MBMS HO : Optimized Multi-RAT mobility, RRM : Cooperative RRM APP : Medical IT, Wireless IPTV, D2D comm, ETWS, 3D Virtual Reality, CR, etc -38-
Reference [1] 3GPP LTE/SAE Documents, 2006-2008 [2] 3GPP LTE-Advanced Workshop Presentation Materials, April, 2008 [3] IWCCF2007, Seamless & Fast Vertical Handover in Heterogeneous Access Networks, May, 2007 [4] ITU-R Documents [5] KRNET2007 [6] ETRI Internal Materials [7] Ryuji Kohno's, YNU/NICT/Medical ICT Consortium [8] IST, E2R Project, Workshop Materials, 2005-39-
Q&A pjsong@etri.re.kr (010-9600-6404) 6404) -40-