Technical Overview of LTE ( Hyung G. Myung)
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The document provides a technical overview of 3GPP LTE (Long Term Evolution). It discusses the evolution of cellular wireless systems from 1G to 3G, and the development of 4G technologies including 3GPP LTE, 3GPP2 UMB, and IEEE 802.16m. It describes the key requirements, enabling technologies, features, and standard specifications of 3GPP LTE. It also outlines the LTE protocol architecture and network architecture, including the roles of eNB, MME, S-GW, and P-GW nodes.
![3GPP LTE
Length of CP
Configuration Nsymb
Normal CP 7
Extended CP 6
Extended CP (∆f = 7.5 kHz)† 3
Configuration CP length NCP,l [samples]
160 (≈ 5.21 µs) for l = 0
Normal CP
144 (≈ 4.69 µs) for l = 1, 2, …, 6
Extended CP 512 (≈ 16.67 µs) for l = 0, 1, …, 5
Extended CP (∆f = 7.5 kHz) † 1024 (≈ 33.33 µs) for l = 0, 1, 2
† Only in downlink
Technical Overview of 3GPP LTE | Hyung G. Myung 21](https://image.slidesharecdn.com/3gpplte-091111135441-phpapp02/85/Technical-Overview-of-LTE-Hyung-G-Myung-22-320.jpg)
![3GPP LTE
LTE Bandwidth/Resource Configuration
Channel
1.4 3 5 10 15 20
bandwidth [MHz]
Number of
6 15 25 50 75 100
resource blocks (NRB)
Number of
72 180 300 600 900 1200
occupied subcarriers
IDFT(Tx)/DFT(Rx)
128 256 512 1024 1536 2048
size
Sample rate [MHz] 1.92 3.84 7.68 15.36 23.04 30.72
Samples per slot 960 1920 3840 7680 11520 15360
*3GPP TS 36.104
Technical Overview of 3GPP LTE | Hyung G. Myung 22](https://image.slidesharecdn.com/3gpplte-091111135441-phpapp02/85/Technical-Overview-of-LTE-Hyung-G-Myung-23-320.jpg)
Technical Overview of LTE ( Hyung G. Myung)
- 1. Technical Overview of 3GPP LTE May 18, 2008 Hyung G. Myung (hgmyung@ieee.org)
- 2. Introduction Cellular Wireless System Evolution • 1G (Early 1980s) – Analog speech communications. – Analog FDMA. – Ex: AMPS • 2G (Early 1990s) – Digital modulation of speech communications. – Advanced security and roaming. – TDMA and narrowband CDMA. – Ex: GSM, IS-95 (cdmaOne), and PDC • 3G (Late 1990s) – Global harmonization and roaming. – Wideband CDMA – Ex: UMTS, cdma2000, and TD-SCDMA Technical Overview of 3GPP LTE | Hyung G. Myung 1
- 3. Introduction Beyond 3G • International Mobile Telecommunications (IMT)-2000 introduced global standard for 3G. • Systems beyond IMT-2000 (IMT-Advanced) is set to introduce evolutionary path beyond 3G. – Mobile class targets 100 Mbps with high mobility and nomadic/ local area class targets 1 Gbps with low mobility. • 3GPP and 3GPP2 are currently developing evolutionary/ revolutionary systems beyond 3G. – 3GPP Long Term Evolution (LTE) – 3GPP2 Ultra Mobile Broadband (UMB) • IEEE 802.16-based WiMAX is also evolving towards 4G through 802.16m. Technical Overview of 3GPP LTE | Hyung G. Myung 2
- 4. Introduction 3GPP Evolution • Release 99 (Mar. 2000): UMTS/WCDMA • Rel-5 (Mar. 2002): HSDPA • Rel-6 (Mar. 2005): HSUPA • Rel-7 (2007): DL MIMO, IMS (IP Multimedia Subsystem), optimized real-time services (VoIP, gaming, push-to-talk). • Long Term Evolution (LTE) – 3GPP work on the Evolution of the 3G Mobile System started in November 2004. – Standardized in the form of Rel-8. – Spec finalized and approved in January 2008. – Target deployment in 2010. – LTE-Advanced study phase in progress. Technical Overview of 3GPP LTE | Hyung G. Myung 3
- 5. Introduction 3GPP2 Evolution • CDMA2000 1X (1999) • CDMA2000 1xEV-DO (2000) • EV-DO Rev. A (2004): VoIP • EV-DO Rev. B (2006): Multi-carrier • Ultra Mobile Broadband (UMB), f.k.a. EV-DO Rev. C – Based on EV-DO, IEEE 802.20, and FLASH-OFDM – Spec finalized in April 2007. – Commercially available in early 2009. Technical Overview of 3GPP LTE | Hyung G. Myung 4
- 6. Introduction IEEE 802.16 Evolution • 802.16 (2002): Line-of-sight fixed operation in 10 to 66 GHz • 802.16a (2003): Air interface support for 2 to 11 GHz • 802.16d (2004): Minor improvements to fixes to 16a • 802.16e (2006): Support for vehicular mobility and asymmetrical link • 802.16m (in progress): Higher data rate, reduced latency, and efficient security mechanism Technical Overview of 3GPP LTE | Hyung G. Myung 5
- 7. 3GPP LTE Requirements of LTE • Peak data rate – 100 Mbps DL/ 50 Mbps UL within 20 MHz bandwidth. • Up to 200 active users in a cell (5 MHz) • Less than 5 ms user-plane latency • 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. • Enhanced multimedia broadcast multicast service (E-MBMS) • Spectrum flexibility: 1.25 ~ 20 MHz • Enhanced support for end-to-end QoS Technical Overview of 3GPP LTE | Hyung G. Myung 6
- 8. 3GPP LTE LTE Enabling Technologies • OFDM (Orthogonal Frequency Division Multiplexing) • Frequency domain equalization • SC-FDMA (Single Carrier FDMA) • MIMO (Multi-Input Multi-Output) • Multicarrier channel-dependent resource scheduling • Fractional frequency reuse Technical Overview of 3GPP LTE | Hyung G. Myung 7
- 9. 3GPP LTE LTE Enabling Technologies - cont. • Single Carrier FDMA (SC-FDMA) – SC-FDMA is a new single carrier multiple access technique which has similar structure and performance to OFDMA. • Utilizes single carrier modulation and orthogonal frequency multiplexing using DFT-spreading in the transmitter and frequency domain equalization in the receiver. – A salient advantage of SC-FDMA over OFDM/OFDMA is low PAPR. • Efficient transmitter and improved cell-edge performance. – H. G. Myung et al., “Single Carrier FDMA for Uplink Wireless Transmission,” IEEE Vehic. Tech. Mag., vol. 1, no. 3, Sep. 2006 – A comprehensive tutorial available at http://hgmyung.googlepages.com/scfdma.pdf. Technical Overview of 3GPP LTE | Hyung G. Myung 8
- 10. 3GPP LTE Key Features of LTE • Multiple access scheme – DL: OFDMA with CP. – UL: Single Carrier FDMA (SC-FDMA) with CP. • Adaptive modulation and coding – DL/UL modulations: QPSK, 16QAM, and 64QAM – Convolutional code and Rel-6 turbo code • Advanced MIMO spatial multiplexing techniques – (2 or 4)x(2 or 4) downlink and uplink supported. – Multi-user MIMO also supported. • Support for both FDD and TDD • H-ARQ, mobility support, rate control, security, and etc. Technical Overview of 3GPP LTE | Hyung G. Myung 9
- 11. 3GPP LTE LTE Standard Specifications • Freely downloadable from http://www.3gpp.org/ftp/Specs/html-info/36-series.htm Specification Description of contents index TS 36.1xx Equipment requirements: Terminals, base stations, and repeaters. TS 36.2xx Physical layer. Layers 2 and 3: Medium access control, radio link control, and radio TS 36.3xx resource control. Infrastructure communications (UTRAN = UTRA Network) including TS 36.4xx base stations and mobile management entities. TS 36.5xx Conformance testing. Technical Overview of 3GPP LTE | Hyung G. Myung 10
- 12. 3GPP LTE Protocol Architecture RRC: Radio Resource Control Layer 3 Control / measurements RLC: Radio Link Control Logical channels Layer 2 MAC: Medium Access Control Transport channels PHY: Physical layer Layer 1 Physical channels Transceiver Technical Overview of 3GPP LTE | Hyung G. Myung 11
- 13. 3GPP LTE LTE Network Architecture • E-UTRAN (Evolved Universal Terrestrial Radio Access Network) UMTS 3G: UTRAN EPC (Evolved Packet Core) MME MME GGSN S-GW/P-GW S-GW/P-GW SGSN S1 RNC RNC eNB eNB X2 NB NB NB NB eNB eNB E-UTRAN NB: NodeB (base station) eNB: E-UTRAN NodeB RNC: Radio Network Controller MME: Mobility Management Entity SGSN: Serving GPRS Support Node S-GW: Serving Gateway * 3GPP TS 36.300 GGSN: Gateway GPRS Support Node P-GW: PDN (Packet Data Network) Gateway Technical Overview of 3GPP LTE | Hyung G. Myung 12
- 14. 3GPP LTE LTE Network Architecture - cont. • eNB – All radio interface-related EPC (Evolved Packet Core) functions MME MME • MME S-GW/P-GW S-GW/P-GW – Manages mobility, UE identity, and security S1 parameters. • S-GW – Node that terminates the eNB eNB interface towards E-UTRAN. X2 • P-GW eNB eNB E-UTRAN – Node that terminates the eNB: E-UTRAN NodeB interface towards PDN. MME: Mobility Management Entity S-GW: Serving Gateway * 3GPP TS 36.300 P-GW: PDN (Packet Data Network) Gateway Technical Overview of 3GPP LTE | Hyung G. Myung 13
- 15. 3GPP LTE LTE Network Architecture - cont. UTRAN SGSN GERAN HSS S3 S1-MME S6a MME PCR S12 Rx+ S11 S7 S4 "LTE-Uu" S10 Serving S5 PDN SGi UE E-UTRAN Gateway Gateway Operator's IP Services S1-U (e.g. IMS, PSS etc.) * Non-roaming architecture * 3GPP TS 23.401 Technical Overview of 3GPP LTE | Hyung G. Myung 14
- 16. 3GPP LTE LTE Network Architecture - cont. RRM: Radio Resource Management RB: Radio Bearer RRC: Radio Resource Control PDCP: Packet Data Convergence Protocol NAS: Non-Access Stratum EPS: Evolved Packet System * 3GPP TS 36.300 Technical Overview of 3GPP LTE | Hyung G. Myung 15
- 17. 3GPP LTE LTE Network Architecture - cont. User-Plane Protocol Stack Control-Plane Protocol Stack * 3GPP TS 36.300 Technical Overview of 3GPP LTE | Hyung G. Myung 16
- 18. 3GPP LTE Frame Structure • Two radio frame structures defined. – Frame structure type 1 (FS1): FDD. – Frame structure type 2 (FS2): TDD. • A radio frame has duration of 10 ms. • A resource block (RB) spans 12 subcarriers over a slot duration of 0.5 ms. One subcarrier has bandwidth of 15 kHz, thus 180 kHz per RB. Technical Overview of 3GPP LTE | Hyung G. Myung 17
- 19. 3GPP LTE Frame Structure Type 1 • FDD frame structure One radio frame = 10 ms One slot = 0.5 ms #0 #1 #2 #3 #18 #19 One subframe = TTI (Transmission Time Interval) Technical Overview of 3GPP LTE | Hyung G. Myung 18
- 20. 3GPP LTE Frame Structure Type 2 • TDD frame structure One radio frame = 10 ms One half-frame = 5 ms One subframe = 1 ms One slot = 0.5 ms Subframe #0 Subframe #2 Subframe #3 Subframe #4 Subframe #5 Subframe #7 Subframe #8 Subframe #9 DwPTS GP UpPTS DwPTS GP UpPTS Technical Overview of 3GPP LTE | Hyung G. Myung 19
- 21. 3GPP LTE Resource Grid One radio frame Slot #0 #19 N symb Resource block = N symb × N sc resource elements RB Subcarrier (frequency) N RB × N sc RB RB N sc Resource element = 12 OFDM/SC-FDMA symbol (time) Technical Overview of 3GPP LTE | Hyung G. Myung 20
- 22. 3GPP LTE Length of CP Configuration Nsymb Normal CP 7 Extended CP 6 Extended CP (∆f = 7.5 kHz)† 3 Configuration CP length NCP,l [samples] 160 (≈ 5.21 µs) for l = 0 Normal CP 144 (≈ 4.69 µs) for l = 1, 2, …, 6 Extended CP 512 (≈ 16.67 µs) for l = 0, 1, …, 5 Extended CP (∆f = 7.5 kHz) † 1024 (≈ 33.33 µs) for l = 0, 1, 2 † Only in downlink Technical Overview of 3GPP LTE | Hyung G. Myung 21
- 23. 3GPP LTE LTE Bandwidth/Resource Configuration Channel 1.4 3 5 10 15 20 bandwidth [MHz] Number of 6 15 25 50 75 100 resource blocks (NRB) Number of 72 180 300 600 900 1200 occupied subcarriers IDFT(Tx)/DFT(Rx) 128 256 512 1024 1536 2048 size Sample rate [MHz] 1.92 3.84 7.68 15.36 23.04 30.72 Samples per slot 960 1920 3840 7680 11520 15360 *3GPP TS 36.104 Technical Overview of 3GPP LTE | Hyung G. Myung 22
- 24. 3GPP LTE Bandwidth Configuration 1 slot Zeros DL or UL symbol Resource block frequency RB N sc N RB × N sc RB M = 12 = 300 = 512 (180 kHz) (4.5 MHz) (7.68 MHz) Zeros * 5 MHz system with frame structure type 1 time Technical Overview of 3GPP LTE | Hyung G. Myung 23
- 25. 3GPP LTE LTE Physical Channels • DL – Physical Broadcast Channel (PBCH) – Physical Control Format Indicator Channel (PCFICH) – Physical Downlink Control Channel (PDCCH) – Physical Hybrid ARQ Indicator Channel (PHICH) – Physical Downlink Shared Channel (PDSCH) – Physical Multicast Channel (PMCH) • UL – Physical Uplink Control Channel (PUCCH) – Physical Uplink Shared Channel (PUSCH) – Physical Random Access Channel (PRACH) Technical Overview of 3GPP LTE | Hyung G. Myung 24
- 26. 3GPP LTE LTE Transport Channels • Physical layer transport channels offer information transfer to medium access control (MAC) and higher layers. • DL – Broadcast Channel (BCH) – Downlink Shared Channel (DL-SCH) – Paging Channel (PCH) – Multicast Channel (MCH) • UL – Uplink Shared Channel (UL-SCH) – Random Access Channel (RACH) Technical Overview of 3GPP LTE | Hyung G. Myung 25
- 27. 3GPP LTE LTE Logical Channels • Logical channels are offered by the MAC layer. • Control Channels: Control-plane information – Broadcast Control Channel (BCCH) – Paging Control Channel (PCCH) – Common Control Channel (CCCH) – Multicast Control Channel (MCCH) – Dedicated Control Channel (DCCH) • Traffic Channels: User-plane information – Dedicated Traffic Channel (DTCH) – Multicast Traffic Channel (MTCH) Technical Overview of 3GPP LTE | Hyung G. Myung 26
- 28. 3GPP LTE Channel Mappings PCCH BCCH CCCH DCCH DTCH MCCH MTCH Logical CCCH DCCH DTCH channels Transport PCH BCH DL-SCH MCH RACH UL-SCH channels Physical PDSCH PBCH PMCH PDCCH channels PRACH PUSCH PUCCH Downlink Uplink Technical Overview of 3GPP LTE | Hyung G. Myung 27
- 29. 3GPP LTE LTE Layer 2 • Layer 2 has three sublayers – MAC (Medium Access Control) – RLC (Radio Link Control) – PDCP (Packet Data Convergence Protocol) DL UL ROHC: Robust Header Compression * 3GPP TS 36.300 Technical Overview of 3GPP LTE | Hyung G. Myung 28
- 30. 3GPP LTE RRC Layer • Terminated in eNB on the network side. • Functions – Broadcast – Paging – RRC connection management – RB (Radio Bearer) management – Mobility functions – UE measurement reporting and control • RRC states – RRC_IDLE – RRC_CONNECTED Technical Overview of 3GPP LTE | Hyung G. Myung 29
- 31. 3GPP LTE Resource Scheduling of Shared Channels • Dynamic resource scheduler resides in eNB on MAC layer. • Radio resource assignment based on radio condition, traffic volume, and QoS requirements. • Radio resource assignment consists of: – Physical Resource Block (PRB) – Modulation and Coding Scheme (MCS) Technical Overview of 3GPP LTE | Hyung G. Myung 30
- 32. 3GPP LTE Radio Resource Management • Radio bearer control (RBC) • Radio admission control (RAC) • Connection mobility control (CMC) • Dynamic resource allocation (DRA) or packet scheduling (PS) • Inter-cell interference coordination (ICIC) • Load balancing (LB) Technical Overview of 3GPP LTE | Hyung G. Myung 31
- 33. 3GPP LTE Other Features • ARQ (RLC) and H-ARQ (MAC) • Mobility • Rate control • DRX (Discontinuous Reception) • MBMS • QoS • Security Technical Overview of 3GPP LTE | Hyung G. Myung 32
- 34. 3GPP LTE DL Overview • DL physical channels – Physical Broadcast Channel (PBCH) – Physical Control Format Indicator Channel (PCFICH) – Physical Downlink Control Channel (PDCCH) – Physical Hybrid ARQ Indicator Channel (PHICH) – Physical Downlink Shared Channel (PDSCH) – Physical Multicast Channel (PMCH) • DL physical signals – Reference signal (RS) – Synchronization signal • Available modulation for data channel – QPSK, 16-QAM, and 64-QAM Technical Overview of 3GPP LTE | Hyung G. Myung 33
- 35. 3GPP LTE DL Physical Channel Processing Scrambling Modulation mapping Mapping onto one or more Layer mapping transmission layers MIMO-related processing Generation of signals for each Precoding antenna port Resource element mapping OFDM signal generation IDFT operation Technical Overview of 3GPP LTE | Hyung G. Myung 34
- 36. 3GPP LTE DL Reference Signal • Cell-specific 2D RS sequence is generated as the symbol-by- symbol product of a 2D orthogonal sequence (OS) and a 2D pseudo-random sequence (PRS). – 3 different 2D OS and ~170 different PRS. – Each cell (sector) ID corresponds to a unique combination of one OS and one PRS ⇒ ~510 unique cell IDs. • CDM of RS for cells (sectors)of the same eNodeB (BS) – Use complex orthogonal spreading codes. • FDM of RS for each antenna in case of MIMO Technical Overview of 3GPP LTE | Hyung G. Myung 35
- 37. 3GPP LTE DL Reference Signal - cont. R0 R0 *With normal CP *3GPP TS 36.211 R0 R0 R0 R0 R0 R0 l =0 l =6 l =0 l=6 R0 R0 R1 R0 R0 R1 R1 R0 R0 R1 R1 R0 R0 R1 R1 l =0 l =6 l =0 l =6 l =0 l=6 l =0 l =6 R0 R0 R1 R1 R2 R3 R3 R0 R0 R1 R1 R2 R0 R0 R1 R1 R2 R3 R3 R0 R0 R1 R1 R2 l =0 l =6 l =0 l =6 l =0 l =6 l =0 l =6 l =0 l =6 l =0 l =6 l =0 l =6 l =0 l=6 Technical Overview of 3GPP LTE | Hyung G. Myung 36
- 38. 3GPP LTE DL MIMO • Supported up to 4x4 configuration. • Support for both spatial multiplexing (SM) and Tx diversity (TxD) – SM • Unitary precoding based scheme with codebook based feedback from user. • Multiple codewords – TxD: SFBC/STBC, switched TxD, CDD (Cyclic Delay Diversity) considered. • MU-MIMO supported. Technical Overview of 3GPP LTE | Hyung G. Myung 37
- 39. 3GPP LTE UL Overview • UL physical channels – Physical Uplink Shared Channel (PUSCH) – Physical Uplink Control Channel (PUCCH) – Physical Random Access Channel (PRACH) • UL physical signals – Reference signal (RS) • Available modulation for data channel – QPSK, 16-QAM, and 64-QAM • Single user MIMO not supported in current release. – But it will be addressed in the future release. – Multi-user collaborative MIMO supported. Technical Overview of 3GPP LTE | Hyung G. Myung 38
- 40. 3GPP LTE UL Resource Block *PUSCH with normal CP Resource Reference block (RB) symbols (RS) Frequency Subcarrier 1 slot (0.5 ms) One SC-FDMA symbol Time Technical Overview of 3GPP LTE | Hyung G. Myung 39
- 41. 3GPP LTE UL Physical Channel Processing Scrambling Modulation mapping Transform precoding DFT-precoding SC-FDMA Resource element mapping modulation SC-FDMA signal generation IDFT operation Technical Overview of 3GPP LTE | Hyung G. Myung 40
- 42. 3GPP LTE SC- SC-FDMA Modulation in LTE UL Localized mapping Subcarrier with an option of Mapping adaptive scheduling or random hopping. M-1 Zeros subcarrier Serial- Parallel { x0 , x1 … , xN −1} to- N- M- -to- { x0 , x1 … , xM −1} ɶ ɶ ɶ DFT IDFT Parallel Serial One SC-FDMA symbol Zeros 0 Technical Overview of 3GPP LTE | Hyung G. Myung 41
- 43. 3GPP LTE UL Reference Signal • Two types of UL RS – Demodulation (DM) RS ⇒ Narrowband. – Sounding RS: Used for UL resource scheduling ⇒ Broadband. • RS based on Zadoff-Chu CAZAC (Constant Amplitude Zero Auto-Correlation) polyphase sequence – CAZAC sequence: Constant amplitude, zero circular auto- correlation, flat frequency response, and low circular cross- correlation between two different sequences. − j 2π r k 2 +qk , k =0,1,2,⋯, L −1; for L even * r is any integer relatively prime L 2 e with L and q is any integer. ak = r k ( k +1) − j 2π + qk , k = 0,1,2,⋯, L −1; for L odd e L 2 B. M. Popovic, “Generalized Chirp-like Polyphase Sequences with Optimal Correlation Properties,” IEEE Trans. Info. Theory, vol. 38, Jul. 1992, pp. 1406-1409. Technical Overview of 3GPP LTE | Hyung G. Myung 42
- 44. 3GPP LTE UL RS Multiplexing User 1 User 2 User 3 subcarriers subcarriers FDM Pilots CDM Pilots Technical Overview of 3GPP LTE | Hyung G. Myung 43
- 45. 3GPP LTE UL RS Multiplexing - cont. • DM RS – For SIMO: FDM between different users. – For SU-MIMO: CDM between RS from each antenna – For MU-MIMO: CDM between RS from each antenna • Sounding RS – CDM when there is only one sounding bandwidth. – CDM/FDM when there are multiple sounding bandwidths. Technical Overview of 3GPP LTE | Hyung G. Myung 44
- 46. 3GPP LTE Cell Search • Cell search: Mobile terminal or user equipment (UE) acquires time and frequency synchronization with a cell and detects the cell ID of that cell. – Based on BCH (Broadcast Channel) signal and hierarchical SCH (Synchronization Channel) signals. • P-SCH (Primary-SCH) and S-SCH (Secondary-SCH) are transmitted twice per radio frame (10 ms) for FDD. • Cell search procedure 1. 5 ms timing identified using P-SCH. 2. Radio timing and group ID found from S-SCH. 3. Full cell ID found from DL RS. 4. Decode BCH. Technical Overview of 3GPP LTE | Hyung G. Myung 45
- 47. 3GPP LTE Random Access • Non-synchronized random access. • Open loop power controlled with power ramping similar to WCDMA. • RACH signal bandwidth: 1.08 MHz (6 RBs) • Preamble based on CAZAC sequence. RA slot = 1 ms TCP TGP CP Preamble * TCP = 0.1 ms, TGP = 0.1 ms *3GPP TR 25.814 Technical Overview of 3GPP LTE | Hyung G. Myung 46
- 48. 3GPP LTE Other Procedures • Synchronization procedures – Radio link monitoring – Inter-Cell synchronization for MBMS – Transmission timing adjustments • Power control for DL and UL • UE procedure for CQI (Channel Quality Indication) reporting • UE procedure for MIMO feedback reporting • UE sounding procedure Technical Overview of 3GPP LTE | Hyung G. Myung 47
- 49. Summary and References Summary • Key technologies of LTE system – Multicarrier-based radio air interface • OFDMA and SC-FDMA – IP-based flat network architecture – Multi-input multi-output (MIMO) – Active interference avoidance and coordination • Fractional frequency re-use (FFR) – Fast frequency-selective resource scheduling Technical Overview of 3GPP LTE | Hyung G. Myung 48
- 50. Summary and References Summary - cont. 3GPP LTE 3GPP2 UMB Mobile WiMAX Channel bandwidth 1.4, 3, 5, 10, 15, and 20 MHz 1.25, 2.5, 5, 10, and 20 MHz 5, 7, 8.75, and 10 MHz DL multiple access OFDMA OFDMA OFDMA UL multiple access SC-FDMA OFDMA and CDMA OFDMA Duplexing FDD and TDD FDD and TDD TDD Subcarrier mapping Localized Localized and distributed Localized and distributed Subcarrier hopping Yes Yes Yes Data modulation QPSK, 16QAM, and 64QAM QPSK, 8PSK, 16QAM, and 64QAM QPSK, 16QAM, and 64QAM Subcarrier spacing 15 kHz 9.6 kHz 10.94 kHz FFT size (5 MHz) 512 512 512 Channel coding Convolutional coding and turbo Convolutional coding, turbo coding, Convolutional coding and coding. and LDPC coding convolutional turbo coding. Block turbo coding and LDPC coding optional. MIMO Multi-layer precoded spatial Multi-layer precoded spatial Beamforming, Space-time coding, multiplexing space-time/frequency multiplexing, space-time transmit and spatial multiplexing block coding, switched transmit diversity, spatial division multiple diversity, and cyclic delay diversity access, and beamforming. Technical Overview of 3GPP LTE | Hyung G. Myung 49
- 51. Summary and References References and Resources • LTE enabling technologies – OFDM/OFDMA • R. van Nee and R. Prasad, OFDM for Wireless Multimedia Communications, Artech House, 2000. – SC-FDMA • H. G. Myung et al., “Single Carrier FDMA for Uplink Wireless Transmission,” IEEE Vehicular Technology Mag., vol. 1, no. 3, Sep. 2006. • http://hgmyung.googlepages.com/scfdma – MIMO • A. Paulraj et al., Introduction to Space-Time Wireless Communications, Cambridge University Press, May 2003. • G. L. Stüber et al., “Broadband MIMO-OFDM Wireless Communications,” Proceedings of the IEEE, Feb. 2004, vol. 92, no. 2, pp. 271-294. – Multicarrier scheduling • G. Song and Y. Li, “Utility-based Resource Allocation and Scheduling in OFDM-based Wireless Broadband Networks,” IEEE Commun. Mag., vol. 43, no. 12, Dec. 2005, pp. 127-134. Technical Overview of 3GPP LTE | Hyung G. Myung 50
- 52. Summary and References References and Resources - cont. • 3GPP LTE – Spec • http://www.3gpp.org/ftp/Specs/html-info/36-series.htm • http://www.3gpp.org/ftp/Specs/html-info/25814.htm (old) – E. Dahlman et al., 3G Evolution: HSPA and LTE for Mobile Broadband, Academic Press, 2007 – H. Ekström et al., “Technical Solutions for the 3G Long-Term Evolution,” IEEE Commun. Mag., vol. 44, no. 3, March 2006, pp. 38-45 – 3G Americas, “Mobile Broadband: The Global Evolution of UMTS/HSPA - 3GPP Release 7 and Beyond" available at http://www.3gamericas.org/pdfs/UMTS_Rel7_Beyond_Dec2006.p df – http://www.LTEwatch.com Technical Overview of 3GPP LTE | Hyung G. Myung 51
- 53. Thank you! May 18, 2008 Hyung G. Myung (hgmyung@ieee.org)