UMTS Long Term Evolution (LTE) 안수현 suhyun.an@rohde-schwarz.com 1ES/GP Rohde & Schwarz, Korea
Overview: Market Trend Date Title of presentation 2
이동통신기술동향 GSM/(E)GPRS WCDMA/HSPA CDMA2000 1xEVDO LTE UMB OFDMA + MIMO 802.11x WiLAN(802.11n) WiMAX(802.16x) Date Title of presentation 3
Overview GSM (EDGE) GSM (EDGE) GSM (EDGE) CDMA2000 WCDMA/ HSPA WCDMA/ HSPA 1xEVDO EDGE II HSPA+ LTE or WiMAX == 요약 == - 현재시장 : 63억인구의약 50% 이동통신이용 - 현재 3GPP 시장점유율 : 약 80% - 3GPP 에서 LTE 전환시, 투자비용최소 - LTE 전환시, 시장점유율유지및향상가능 - LTE 기술이 WiMAX 기술대비우위 단, 2년정도의 lunching gap - WiMAX의이동통신시장진입의어려움 LTE 대비기술력저하 Nothing 현재이동통신현황 MIMO 적용 OFDMA 적용 투자비용의과다 - WiMAX 기대시장 기존인터넷사업을무선화시시장형성 USB, Note-PC 등에탑재된제품시장 802.11x (WiLAN) 802.11n 802.11n Date Title of presentation 4
UMTS Long Term Evolution (LTE) Ambitious targets Significantly increased peak data rate e.g. 100 Mbps (downlink) and 50 Mbps (uplink) Significantly improved spectrum efficiency ( e.g. 2-4 x Release 6) Improved latency: Possibility for a radio access network latency (user plane UE RNC - UE) below 10 ms Significantly reduced control plane latency Scaleable bandwidth 5, 10, 15, 20 MHz Smaller bandwidths to allow flexibility in narrow spectral allocations Support for inter-working with existing 3G systems and non-3gpp specified systems Reduced CAPEX and OPEX including backhaul Cost effective migration from release 6 UTRA radio interface and architecture Efficient support of the various types of services, especially from the PS domain System should be optimized for low mobile speed but also support high mobile speed Operation in paired and unpaired spectrum should not be precluded (FDD and TDD modes) Enhanced Multimedia Broadcast Multicast Services (E-MBMS) Date Title of presentation 5
UMTS Long Term Evolution(LTE) Deployment scenarios Standalone deployment scenario for EUTRAN Integrating with existing 2G/3G deployment scenario Handover to and from GERAN and UTRAN will be supported Study on handover to and from WiMAX and cdma2000 based networks has been finalized LTE as overlay network on another frequency to increase overall capacity in certain areas Narrower LTE carriers can also be introduced in legacy frequency bands such as 900 MHz LTE interworking with 3GPP2/WiMAX Date Title of presentation 6
Network Structure Date Title of presentation 7
Network Architecture UMTS Gateways and Interworking Functions GSM (MAP) ANSI-41 (IS-634) IP-Net v4, v6 IMT-2000 CN (ITU-T) CN RAT Mapping IMT-DS (Direct Spread) IMT-TC (Time Code) IMT-MC (Multi Carrier) IMT-SC (Single Carrier) IMT-FT (Freq. + Time) UTRA FDD (WCDMA) 3GPP UTRA TDD (TD-S/CDMA) 3GPP cdma2000 3GPP2 UWC-136 (EDGE) UWCC/3 GPP DECT ETSI IMT-2000 RAT (ITU-R) Date Title of presentation 8
Network Architecture 3GPP Circuit Switched Packet Switched Date Title of presentation 9
Network Architecture 3GPP VLR (Visitor Location Register) - User 의 Ciphering and authentication 정보 - 실제 Location Area 의정보 HLR (Home Location Register) - IMSI 기초로단말의위치를지속적으로관리하는데이터베이스 - 착신호를받아단말의등록된 VLR 영역의 MSC 로해당호전달 - 실제 VLR 의 Location 정보 ( 단말의실제위치정보 ) EIR (Equipment Identity Register) - IMEI 등록및관리 MSC (Mobile Switching Center) - location DB 와연동 SGSN (Serving GPRS Support Node) - 서비스지역내에서이동국과의 Packet 전달을담당하는 Node - 단말에대한이동성및보안기능담당 - HLR 과연동하여 Mobility 관리 (Packet 의이동 ) - SGSN 과 GGSN 의 Session 관리 (WAP,SMS, MMS 등 ) GGSN - Packet Data 망 (Mobile Network) 과외부 Packet Data 망 (IP Network) 로의 Gateway - SGSN 으로부터오는 Packet 을적당한 PDP(Packet Data Protocol) 형식으로변환하여전송 Date Title of presentation 10
Network Architecture 3GPP+LTE Date Title of presentation 11
LTE Protocol Architecture New network elements and functional split enb functions: l RRM, Radio Bearer Control, Radio Admission Control, Connection Mobility Control, Scheduling for uplink and downlink l IP header compression and encryption of user data stream l Selection of an MME at UE attachment l Routing of user plane data towards SAE Gateway l Scheduling and transmissino of paging messages originated from MME l Scheduling and transmission of broadcast informationoriginated from MME or O&M l Measurement and measurement reporting configuration MME functions: Distribution of paging messages to enbs Security Control Idle state mobility control SAE bearer ccontrol Ciphering and integrity protection of NAS Signalling SAE Gateway: Termination of user plane packets for paging reasons Switching of user plane for support of UE mobility Date Title of presentation 12
OFDMA Date Title of presentation 13
Wideband Signal Non-Linear System Fading SINR Amp. Design Scalable BW Date Title of presentation 14
Coherence Bandwidth Coherence BW - Max Frequency for Flat with 1 signal Time domain view x(t) - Max Frequency for Comparison with 2 signal Freq. domain view X ( f ) σ τ delay spread Range of freq over which response is flat B c High correlation of amplitude between two different freq. components Date Title of presentation 15
Block Diagram Transmitter Receiver Date Title of presentation 16
How to Increase Data Rates: Modulation b1 b3 b2 b5 b4 b7 b6 b8 bit to symbol mapping b1 b1 b2 b1 b2 b3 b4 b1 b2 b3 b4 b5 b6 (+1) (-1,+1) (+1,+1) (-1) BPSK 1 symbol = 1 bit (-1,-1) (+1,-1) QPSK 1 symbol = 2 bit 16 QAM 1 symbol = 4 bit 64 QAM 1 symbol = 6 bit optional for WiMAX Date Title of presentation 17
How to reach higher data rates? Time 1. Possibility: Reduce Symbol Time Time delay spread S 1 S 2 time S 1 S 1 S 1 S 2 S 2 S 2 time Date Title of presentation 18
Weak Points & Solution ICI (Inter-Carrier Interference) copy Time ISI (Inter-Symbol Interference) cyclic prefix Symbol 2 useful symbol time OFDMA symbol time Date Title of presentation 19
ISI and ICI: Guard Intervall Symbol l-1 L l l+1 L h( n) TG > Delay Spread Delay spread n Receiver DFT Window L L L L L L Guard Intervall guarantees the supression of ISI! But, there is some week point in the Amplifier Date Title of presentation 20
Guard Intervall as Cyclic Prefix Cyclic Prefix Symbol l-1 L l l+1 L h( n) TG > Delay Spread Delay spread n Receiver DFT Window L L L L L L Cyclic Prefix guarantees the supression of ISI and ICI! Date Title of presentation 21
Degradation due to Frequency Offset Channel j 2 n e π f s ( n ) r( n) l l f Samples f f 0 f 1 f 2 f 3 f 0 f 1 f 2 f 3 Date Title of presentation 22
Degradation due to Clock Offset Channel s ( n ) ε r( n) l l f k Samples f f 0 f 1 f 2 f 3 f 0 f 1 f 2 f 3 Date Title of presentation 23
Date Title of presentation 24 Difference between OFDM and OFDMA l OFDM allocates users in time domain only l OFDMA allocates users in time and frequency domain Time domain Time domain Frequency domain Frequency domain User 3 User 3 User 2 User 2 User 1 User 1
Localized versus Distributed FDMA Date Title of presentation 25
OFDMA vs SC-FDMA Date Title of presentation 26
MIMO Date Title of presentation 27
MIMO (Multiple In Multiple Out) l Technical Overview for l DEGE Evolution l WiMAX l HSPA+ l LTE l IEEE 802.11n l 1xEVDO Rev C (UMB) UMB = Universal Mobile Broadband Date Title of presentation 28
SU-MIMO versus MU-MIMO s1 s2 sn UE1 UE2 UEn SU (Single User)-MIMO l Goal: to increase user data rate l Simultaneous transmission of different data streams to 1 user l Efficient when the user experiences good channel conditions MU (Multiple User)-MIMO l Goal: to increase sector capacity l Selection of the users experiencing good channel conditions l Efficient when a large number of users have an active data transmission simultaneously Date Title of presentation 29
MIMO & SIMO & MISO MIMO 2x2 Receiver SIMO 1x2 Receiver Transmitter Transmitter Transmitter MISO 2x1 Receiver Date Title of presentation 30
MIMO modes Transmit diversity (TxD) 사용목적 : Reliability 향상 (Get a higher SNR at the Rx) Replicas of the same signal sent on several Tx antennas Array gain : Power Diversity gain : STBC/SFBC No Feedback Spatial multiplexing (SM) 사용목적 : Data Throughput 향상 Different data streams sent simultaneously on different antennas Higher data rate No diversity gain Limitation due to path correlation Beamforming 사용목적 : Reliability/Data Throughput 향상 Intelligent Antenna : Switched/Adaptive Antenna Some Feedback CDD (Cyclic Delay Diversity) 사용목적 : Reliability 향상 (Frequency Selectivity 및 Channel Decoder 의 Performance 향상 ) Date Title of presentation 31
LTE MIMO Downlink modes Transmit diversity: Space Time Block Coding (STBC), Space Frequency Block Coding (SFBC) 2TX : STBC / 4TX : STBC+SFBC Increasing robustness of transmission Spatial Multiplexing 에적용가능 (2X1 or 3X2 or 4X2 MIMO 인경우 ) Beamforming 적용 (Adaptive Antenna) Indoor=TXD, Outdoor=BF 적합 Open-SM & RI=1 일때, TXD 적용 Spatial multiplexing: Codebook based precoding Transmission of different data streams simultaneously over multiple spatial layers Beamforming 적용 (Adaptive Antenna) CDD 적용 (Zero, small delay and large delay) Closed-SM : 저속 UE, PMI/RI 를 Feedback 받아 Layer/Codeword/Precodeing 결정 (Zero, small Delay) Open-SM : 고속 UE, RI 만이용하여 Layer/Codeword/Precoding 처리 (Large Delay &RI>1) Date Title of presentation 32
RX Diversity = SIMO A B Transmitter Receiver same signal via different paths => different fading C SNR (db) Received Signals Aim: increase of S/N ratio increase of throughput Switched Diversity Maximum Ratio Combining C = max(a,b) C = (A+B) Date Title of presentation 33
Receive Diversity Date Title of presentation 34
TX Diversity = MISO Intelligence on TX side Intelligence on RX side TX Data Data Processing TX RX Data Processing RX Data Motivation for Alamouti Space-Time-Coding: - increase of range, - improvement of BER, - improvement of antenna diversity, - improvement of signal quality Date Title of presentation 35
Space Time Coding Transmitter Section of the input bit-stream s1 s2 s1 -s2* s2 s1* time s1 s2 -s2* s1* space Alamouti Matrix Matrix A s1 s2 -s2* s1* s1 -s2* s2 s1* Receiver math. s1 s2 operation = s1 s2 Date Title of presentation 36
Transmit diversity Date Title of presentation 37
Spatial Multiplexing (MIMO 2x2) s1 s3 s1 s2 s3 s4 TX RX s1 s2 s3 s4 s2 s4 Motivation for Space-Time-Coding with Matrix B: - increase of data rate by multiplexing (theory by factor 2) Date Title of presentation 38
MIMO with the SMU: K74 SW option Date Title of presentation 39
The MIMO promise Channel capacity grows linearly with antennas Max Capacity ~ min(n TX, N RX ) Assumptions Perfect channel knowledge Spatially uncorrelated fading Reality Imperfect channel knowledge Correlation 0 and rather unknown Date Title of presentation 40
MIMO channel know s1 MIMO r1 r = H s + n s2 r2 Singular Value Decomposition ~ s1 channel H SISO ~ r1 wanted ~ r = D ~ s + ~ n ~ ~ s2 channel D r2 Date Title of presentation 41
MIMO channel s1 MIMO h 11 r1 H = h 11 h 21 h 12 h 22 This is the reality D = d 1 0 0 d 2 What we like to have s2 ~ s1 s2 h 12 h 21 h 22 channel H SISO d 1 channel D r2 Mathematical Wizard: SVD ~ r1 ~ ~ d 2 r2 Date Title of presentation 42
Singular Value Decomposition (SVD) h 11 h r = H 12 s + n h 21 h 22 hd 11 1 h0 12 r = U H (V*) s + n h0 T 21 hd 22 2 (U*) T (U*) T d (U*) T 1 0 r = U D (V*) T s + (U*) T n 0 d 2 ~ r = (U*) T U d 0 D 1 (V*) T ~ s + (U*) T n~ 0 d 2 Date Title of presentation 43
Downlink spatial multiplexing - precoding l The signal is pre-coded at Node B side before transmission l Optimum precoding matrix is selected from predefined codebook known at Node B and UE side l UE estimates the channel, selects the best precoding matrix at the moment and sends back its index Date Title of presentation 44
MIMO: avoid inter-channel interference e.g. linear precoding: V 1,k Y=H*F*S+V S Link adaptation Transmitter F x k H + + y k Space time receiver V M,k Feedback about H Idea: F adapts transmitted signal to current channel conditions Date Title of presentation 45
MIMO Precoding in LTE (DL) Tx diversity (2 antennas) 1 code word Layer Mapper Precoding Resource elementmapper Resource elementmapper f t Symbols d(1) d(0) t t d(0) d(1) t t d(1) d(0) d(0) * -d(1)* f d(1) d(0) d(0) * -d(1)* t Tx 1 Tx 2 t Space Frequency Coding (SFC) Date Title of presentation 46
MIMO Precoding in LTE (DL) Tx diversity (4 antennas) f 0 0 d(1) Tx 1 d(0) t 1 code word f d(3) t Symbols d(3) d(2) d(1) d(0) t t t t d(0) d(1) d(2) d(3) t t t t 0 d(3) 0 0 d(2) 0 d(2)* -d(3)* d(1) 0 d(0)* 0 d(0) 0 -d(1)* Not all antennas transmit at the same time and frequency! 0 f f d(2) 0 0 0 0 d(0)* -d(1)* d(2)* -d(3)* 0 0 Tx 2 t Tx 3 t Tx 4 t Date Title of presentation 47
MIMO Precoding in LTE (DL) Spatial multiplexing Code book for precoding Code book for 2 Tx: Codebook Number of layers υ index 1 2 0 1 1 1 0 0 2 0 1 1 0 1 1 1 1 2 1 1 2 1 1 1 1 1 2 1 2 j j 3 1 1 2 1-1 1 4 2 j 1 1 5 2 j - - Additional multiplication of the layer symbols with codebook entry Date Title of presentation 48
MIMO Precoding in LTE (DL) Spatial multiplexing Code book for precoding 2 examples for 2 layers and 2 Tx antennas t t d(1) d(0) b(1) b(0) Layer 1 Layer 2 1 2 1 0 0 1 1 2 1 2 f f d(1) d(0) b(1) b(0) Tx 1 t Tx 2 t t t d(1) d(0) b(1) b(0) Layer 1 Layer 2 1 2 1 1 1 1 f f Tx 1 t Tx 2 t Date Title of presentation 49
But there is more to LTE layer 1 than just MIMO LTE physical layer procedures Cell search Link Adaptation Power control Uplink synchronisation and Uplink timing control Random access related procedures Support of HARQ related procedures Date Title of presentation 50
Some technical details of LTE / EUTRA Date Title of presentation 51
UMTS Long Term Evolution (LTE) All new again, here s what is most important: l New radio transmission schemes l OFDMA in downlink: Orthogonal Frequency Division Multiple Access l SC-FDMA in uplink: Single Carrier Frequency Division Multiple Access l MIMO Multiple antenna technology l New radio protocol architecture l Complexity reduction l Focus on shared channel operation, no dedicated channels any more l New network architecture l New functional split between radio network nodes l More functionality in the base station (enodeb) l MBMS l Focus on packet switched domain l System architecture evolution (SAE) l Support of Multimedia Broadcast, Multicast Service Date Title of presentation 52
LTE Physical Layer Date Title of presentation 53
LTE Downlink: Physical layer tasks Error detection on the transport channel and indication to higher layers FEC encoding/decoding of the transport channel Hybrid ARQ soft-combining Rate matching of the coded transport channel to physical channels Mapping of the coded transport channel onto physical channels Power weighting of physical channels Modulation and demodulation of physical channels Frequency and time synchronisation Radio characteristics measurements and indication to higher layers Multiple Input Multiple Output (MIMO) antenna processing Transmit Diversity (TX diversity) Beamforming RF processing(note: RF processing aspects are specified in the TS 36.100 series) Date Title of presentation 54
LTE: new physical channels for data and control Physical Control Format Indicator Channel PCFICH: Indicates Format of PDCCH Physical Downlink Control Channel PDCCH: Downlink and uplink scheduling decisions Physical Downlink Shared Channel PDSCH: Downlink data Physical Hybrid ARQ Indicator Channel PHICH: ACK/NACK for uplink packets Physical Uplink Shared Channel PUSCH: Uplink data Physical Uplink Control Channel PUCCH: ACK/NACK for downlink packets, scheduling requests, channel quality info Date Title of presentation 55
LTE Downlink: Downlink Physical Channels - Physical Downlink Shared Channel, PDSCH: Used for data transfer, shared principle, variable modulation Mapping between DL-SCH and PCH MBMS information can be mapped - Physical Downlink Control Channel, PDCCH specific control information, shared principle, fixed modulation QPSK Carries scheduling decision from enodeb Informs UE about resource allocation fo PCH and DL-SCH HARQ information related to DL-SCH UL scheduling grant Mapped to 2-4 symbols in case of less than 10 RB Mapped to 1-3 symbols in case of bigger than 10 RB - Common Control Physical Channel, CCPCH General control information, broadcast principle, fixed modulation QPSK - Physical Multicast Channel, PMCH Like PDSCH, but no transmit multiplexing Date Title of presentation 56
LTE Downlink: Downlink Physical Channels - Physical control format indicator channel, PCFICH : The physical control format indicator channel carries information about the number of OFDM symbols (1-3 or 2-4) used for transmission of PDCCHs in a subframe. Only QPSK. Transferred in every sub-frame - Physical HARQ Indicator Channel, PHICH The PHICH carries the hybrid-arq ACK/NAK, fixed modulation QPSK - Physical Broadcast Channel PBCH General control information, broadcast principle, fixed modulation QP나 MIB (Master Information Block) Transmission 4 subframes within a 40ms interval 40 ms timing is blindly detected Date Title of presentation 57
LTE Uplink: Uplink Physical Channels - Physical Uplink Shared Channel, PUSCH For user data, shared scheduling principle, variable modulation scheme: QPSK, 16- QAM, 64-QAM. Timing similar to downlink - Physical Uplink Control Channel, PUCCH For uplink control information, never transmit simultaneous to PUSCH. Frequency and time multiplexed, fixed modulation scheme: QPSK. Date Title of presentation 58
LTE Physical Layer: OFDMA in downlink Date Title of presentation 59
LTE Downlink: How does the OFDMA signal look like? FFT 5 MHz Bandwidth Sub-carriers Symbols Guard I ntervals Frequency Time Each sub-carrier (frequency channel) carries a separate low-rate stream of data Frequencies are chosen so that the modulated data streams are orthogonal to each other Each sub-carrier is independently modulated A guard time is added to each symbol (cyclic prefix in LTE) Symbol duration is relatively long compared to channel delay spread -> less intersymbol interference Date Title of presentation 60
LTE Downlink: OFDMA Time/Frequency Representation OFDM symbols (time domain) Sub-carrier spacing in LTE = 15 khz (7.5 khz for MBMS scenarios) Data is allocated in multiples of resource blocks 1 resource block spans 12 sub-carriers in the frequency domain and 1 slot in the time domain Resource block size is identical for all bandwidths Normal scenario: carrier spacing of 15 khz Big cell scenario: 7,5 khz + extended guard time Sub carriers (frequency domain) 1 LTE Resource Block = 12 sub-carriers 0 0 1 LTE slot of 0.5 ms = 6 / 7 OFDM symbols dep. on cyclic prefix length (3 symbols for 7.5 khz spacing / MBMS scenarios) Date Title of presentation 61
LTE Downlink OFDMA time-frequency multiplexing 1 resource block = 180 khz = 12 subcarriers Subcarrier spacing = 15 khz frequency 1 slot = 0.5 ms = 7 OFDM symbols** UE1 UE2 UE3 1 subframe = 1 ms= 1 TTI*= 1 resource block pair UE4 UE5 UE6 *TTI = transmission time interval ** For normal cyclic prefix duration time QPSK, 16QAM or 64QAM modulation Date Title of presentation 62
LTE spectrum flexibility l LTE physical layer supports any bandwidth from 1.4 MHz to 20 MHz in steps of 180 khz (resource block) l Current LTE specification supports only a subset of 8 different system bandwidths l All UEs must support the maximum bandwidth of 20 MHz Channel Bandwidth [MHz] Channel bandwidth BW Channel [MHz] FDD mode TDD mode 1.4 6 [TBD] 1.6 n/a [7] 3 15 [TBD] 3.2 n/a [16] 5 25 25 10 50 50 15 75 75 20 100 100 Channel edge Resource block Transmission Bandwidth Configuration [RB] Transmission Bandwidth [RB] Channel edge number of resource blocks Active Resource Blocks DC carrier (downlink only) Date Title of presentation 63
LTE Downlink: Downlink slot and (sub)frame structure Symbol time, or number of symbols per time slot is not fixed One radio frame, T f = 307200 T s = 10 ms One slot, T slot = 15360 T s = 0.5 ms #0 #1 #2 #3 #18 #19 One subframe We talk about 1 slot, but the minimum resource is 1 subframe = 2 slots!!!!! ( 15000 2048) Ts = 1 Ts = 32.522 ns Date Title of presentation 64
LTE Downlink: baseband signal generation code words layers antenna ports Scrambling Scrambling Modulation Mapper Modulation Mapper Layer Mapper Precoding OFDM Mapper OFDM Mapper OFDM signal generation OFDM signal generation Avoid constant sequences QPSK 16 QAM 64 QAM For MIMO Split into Several streams if needed Weighting data streams for MIMO 1 OFDM symbol per stream 1 stream = several subcarriers, based on Physical ressource blocks Date Title of presentation 65
LTE Downlink: Bandwidth agnostic L1 One downlink slot, T slot RB DL BW 6 N BW N 110 N DL N BW RB BW Will be defined by RAN4 Effective bandwidth is a multiple of physical ressource block, i.e. 12 * 15kHz or 24 * 7,5 khz Configuration RB N BW DL N symb DL N symb Normal cyclic prefi x Extended cyclic prefi x f f = 15 khz f =15 khz = 7.5 khz 12 24 Frame structure t ype 1 7 6 3 Frame structure t ype 2 9 8 4 D L su bc a r rie rs N D L B W O n e re so u rc e b loc k, N R B su bc a r rie r s Resource element DL N symb OFDM symbols Date Title of presentation 66
LTE Downlink: Resource-element Groups(REG) Basic unit for mapping of PDCCH, PHICH, PCFICH Resource-element groups are used for defining the mapping of control channels to resource element Mapping of a symbol-quadruplet <z(i), z(i+1),z(i+2),z(i+3)> onto a REG is defined such that elements z(i) are mapped to resource elements (k,l) of the REG not used for cell-specific reference signals in creasing order of i and k Date Title of presentation 67
Modulation Physical channel PDSCH PMCH Physical channel PBCH Physical channel PCFICH Physical channel PDCCH Physical channel PHICH Modulation schemes QPSK, 16QAM, 64QAM QPSK, 16QAM, 64QAM Modulation schemes QPSK Modulation schemes QPSK Modulation schemes QPSK Modulation schemes BPSK Date Title of presentation 68
LTE Downlink: Mapping Spatial Multiplexing Transmission rank Number of code words Codeword-to-layer mapping 1 1 (0) (0) x ( i) = d ( i) 2 2 (0) (0) x ( i) = d ( i) 2 code words are sent = higher data rate 3 2 4 2 (1) x ( i) = d (0) (1) ( i) d ( i) is mapped to layer 0 (1) d ( i) is mapped to layer 1 and 2 (0) d ( i) is mapped to layer 0 and 1 (1) d ( i) is mapped to layer 2 and 3 Transmit Diversity Number of layers Number of code words Codeword-to-layer mapping 1 1 ( 0) ( 0) x ( i) = d ( i ) i = 0,1,..., M symb 1 2 1 (0) (0) x ( i) = d (2i) (1) (0 ) i = 0,1,..., x ( i) = d (2i + 1) ( M symb 1) 2 1 code word is sent on separate pathes = better SNR 4 1 Date Title of presentation 69
Date Title of presentation 70 LTE Downlink: Precoding Number of antenna ports Transmission rank Codebook P ρ 1 1 [] 1 - - - - - 1 0 1 1 0 1 1 2 1 1 1 2 1 j 1 2 1 j 1 2 1 2 2 1 0 0 1 2 1 1 1 1 1 2 1 j j 1 1 2 1 - - - 1 2 3 4 4 Precoding base on cyclic delay diversity, UE proposes which Codebook entry shall be selected by transmitter
LTE Downlink: Downlink Reference Signals Of course, there will be reference signals Cell-specific reference signals, associated with non-mbsfn transmission MBSFN reference signals, associated with MBSFN transmission UE-specific reference signals (supported in frame structure type 2 only) Downlink reference signal(s) can be used for Downlink-channel-quality measurements Downlink channel estimation for coherent demodulation/detection at the UE Cell search and initial acquisition (carries cell ID) Date Title of presentation 71
LTE Downlink: Cell-specific Ref. Signals Normal and extended CP 504 unique Cell ID 168(N1) Cell ID group, 3(N2) Cell ID within each group Cell ID = 3xN1+N2 = 0~503 index 504 pseudo-random sequences One to one mapping between the Cell ID and Pseudo-random sequences Transmit on antenna port {0,1,2,3} Cell-specific Frequency Shift (N1 mod 6) (effective with RS boosting) 1 RE shift from current RS position in case of next Cell ID index Pseudo-random sequence generation cell (1) ID N ID = 3N + N (2) ID r s 1 1 ( m) = N 2 2 PDSCH ( 1 2 c(2m) ) + j ( 1 2 c(2m+ 1) ), m= 01,,..., 12 1 l, n RB ( ( ) ) ( cell ) cell 7 ns + 1 + l+ 1 2 N ID + 1+ N ID NCP c = 2 + init 2 10 n s is the slot number within a radio frame l is the OFDM symbol number within the slot The pseudo-random sequence c(i) is a length-31 Gold sequence Date Title of presentation 72
LTE Downlink, Common Control physical channel: Downlink Reference Signals - mapping 1 antenna configuration R 0 R 0 One antenna port R 0 R 0 R 0 l = 0 l = 6 l = 0 l = 6 R 0 R 0 R 0 Pilots are place that each antenna can be recognised Resource element ( k, l) R 0 R 0 R 1 R 1 Two antenna ports R 0 R 0 R 0 R 0 R 1 R 1 R 1 R 1 Not used for transmission on this antenna port 2 antenna configuration Reference symbols on this antenna port R 0 l = 0 l = 6 l = 0 l = 6 R 0 R 1 l = 0 l = 6 l = 0 l = 6 R 1 4 antenna configuration R 0 R 0 R 1 R 1 R 2 R 3 Four antenna ports R 0 R 0 R 0 R 0 R 1 R 1 R 1 R 1 R 2 R 2 R 3 R 3 R 0 R 0 R 1 R 1 R 2 R 3 l = 0 l = 6 l = 0 l = 6 even-numbered slots odd-numbered slots l = 0 l = 6 l = 0 l = 6 even-numbered slots odd-numbered slots l = 0 l = 6 l = 0 l = 6 even-numbered slots odd-numbered slots l = 0 l = 6 l = 0 l = 6 even-numbered slots odd-numbered slots Antenna port 0 Antenna port 1 Antenna port 2 Antenna port 3 Date Title of presentation 73
LTE Downlink: Hopping/Boosting for DL RS Cell-specific frequency hopping or shifting (FH/FS) is supported No hopping The mode of operation in a cell is static FH/FS sequence acquired from cell group ID (FH/FS per sub-frame) There is one-to-one mapping between the RS hopping sequence and the two-dimensional PRBS Blind detection of hopping mode and non-hopping mode by UE RS power Boosting Motivation : provisioning of enough RS power to the cell edge UEs Boosting of all of the unicast RS By the NodeB configuration, puncturing can be applied (UE is informed by system information) to data subcarriers in the same OFDM symbol Date Title of presentation 74
Initial synchronization BCH and SCH always located at the center Primary synchronisation channel: DL RB N N = d n 2 RB sc ( n), k = n 31+ 0,..., 61 a k, l = Created from Zadoff-Chu sequence (zero Autocorrelation codes) The primary synchronization signal is transmitted on 72 active subcarriers, centred around the DC subcarrier. Secondary synchronisation channel: = N symb 1 Created from Zadoff-Chu sequence (zero Autocorrelation codes) The primary synchronization signal is transmitted on 72 active subcarriers, centred around the DC subcarrier. secondary synchronization signal is transmitted in and only in slots where the primary synchronization signal is transmitted. l DL DL RB N N = d n 2 RB sc ( n), k = n 31+ 0,..., 61 a k, l = l DL = N symb 2 Date Title of presentation 75
Initial synchronization : PSS The sequence for the PSS is generated from a freq.-domain Zadoff-Chu sequence (Length-62) d u ( n) e j e πun( n+ 1) j 63 = πu( n+ 1)( n+ 2) 63 n= 0,1,...,30 n= 31,32,...,61 <TS 36.211 / Table 6.11.1.1-1> c ( ) ~ 0 n = c (( n+ N c ( n) = c ~ (( n+ N 1 (2) ID (2) ID )mod 31) + 3) mod 31) (2) N ID { 0,1,2} c ~ ( i) 1 2x( i ) = 0 i 30 ( x( i + 3) + x( i )) mod 2, 0 25 x( i + 5) = i Background of Zadoff-Chu Sequence Appeared in IEEE Trans. I in 1972 Poly-phase sequence Cyclic autocorrelations are zero for all non-zero lags Non-zero cross-correlations PAPR이낮아 ( 신호의 Amplitude 일정 ) 전력소모적측면에서유리 CAZAC (Constant Amplitude Zero Auto Correlation) Sequence 의일종 Date Title of presentation 76
Initial synchronization : SSS The sequence for the PSS is an interleaved concatenation of two m-sequence (length 31) The concatenated sequence is scrambled with a scrambling sequence given by PSS 2 m-sequences are differ between subframe 0 and subframe 5 s d(2n) = s s d(2n+ 1) = s ( m0) 0 ( m1 ) 1 ( m1 ) 1 ( m0) 0 ( n) c ( n) c ( n) c 0 1 ( n) c 0 1 ( n) ( n) ( m0) ( n) z1 ( n) ( m1) ( n) z ( n) 1 in subframe 0 in subframe 5 in subframe 0 in subframe 5 ~ (2) ( m c 0( n) = c (( n+ NID ) mod31) 0 ) s ~ 0 ( n) = s ( n+ m0 ) mod31) ( ) ~ (2) ( m ) c n = c(( n+ N + 3) mod31) 1 s ( n) = ~ s ( n+ m ) mod31 1 ID ( ) z m ( ) ~ 1 0 n = z (( n+ ( m0 mod8)) mod31) ( ) z m n) = ~ z (( n+ ( mod8)) mod31) 1 1 ( m1 1 ( ) 1 <TS 36.211 / Table 6.11.2.1-1> Date Title of presentation 77
LTE Downlink: BCH Primary BCH Master information block of system information is transmitted on Primary BCH L1 parameters (e.g. DL system BW[4bits], etc System frame Number (SFN) PHICH duration (1bit) PHICH resource (2bits) Etc Dynamic BCH After successful reception of PBCH, UE can read D-BCH in PDSCH (including PCFICH and PDCCH) which carries system information not included in PBCH Uplink information (uplink bandwidth, uplink RS configuration and TX power PRACH information (time/freq-domain configuration, preamble format, root sequence index, zero correlation zone length, high-speed flag, power setting, RA-RNTI) Sounding reference signal information (subframes with SRS transmission) PUCCH, PUSCH information (base sequence group, hopping pattern, ) One or more PLMN identities and related information Tracking Area Code Cell Identity Number of transmit antennas RS transmit power Etc Date Title of presentation 78
LTE Downlink: BCH The coded BCH transport block is mapped to four subframes (slot#1 in subframe #0) BCH mapped to 4 OFDM symbols within a subframe Each subframe is assumed to be self-decodable, i.e. the BCH can be decoded from a signal reception, assuming sufficiently good channel conditions Single (fixed-size) transport block per TTI (40ms) No HARQ Cell-specific scrambling, BPSK with ½ tail-biting Conv. Code, TX diversity(1,2,4) 6RBs = 72 subcarries (excluding DC) PBCH is mapped into RE assuming RS from 4 antennas are used at enb, irrespective of the actual number of TX antenna Different transmit diversity schemes per # of antennas # of ant=2 : SFBC # of ant=4 : SFBC + FSTC (Frequency Switching Transmit Diversity) No explicit bits in the PBCH to signal the number of TX antennas at enb PBCH encoding chain includes CRC masking dependent on the number of configured TX antennas at enb Blind detection of the number of TX antenna using CRC masking by UE Date Title of presentation 79
LTE Downlink Configuration of synchronization signals 10 ms radio frame 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Primary synchronization signal Secondary synchronization signal 0.5 ms slot 1 ms subframe Screenshot of R&S SMU200A signal generator Date Title of presentation 80
LTE Downlink Configuration of physical broadcast channel 10 ms radio frame 1 2 3 4 5 6 7 1 2 3 4 5 6 7 0.5 ms slot 1 ms subframe Primary synchronization signal Secondary synchronization signal Physical Broadcast Channel (PBCH) PBCH has 40 ms transmission time interval Date Title of presentation 81
LTE downlink Synchronization and reference signals, PBCH 10 subframes = 140 OFDM symbols 50 resource blocks in 10 MHz Screenshot of R&S SMU200A signal generator Date Title of presentation 82
LTE downlink Hierarchical cell search scheme Physical layer cell identity (1 out of 504) identified by: Physical layer cell identity group 0 1.. 167 Physical layer identity 0 1 2 0 1 2 0 1 2 Date Title of presentation 83
LTE Downlink Cell search procedure Physical layer cell identity (1 out of 504) 1. Primary synchronization signal: 3 possible sequences to identify the cell s physical layer identity (0, 1, 2) Transmitted every 5 ms to identify 5 ms timing Downlink reference signal 2. Secondary synchronization signal: 168 different sequences to identify physical layer cell identity group Transmitted every 5 ms to identify radio frame timing 3. Physical broadcast channel (PBCH): Carrying broadcast channel with predefined information: system bandwidth, number of transmit antennas, reference signal transmit power, system frame number, Date Title of presentation 84
Initial synchronization BCH and SCH always located at the center 20MHz bandwidth SCH BCH 10 MHz bandwidth 1.25 MHz bandwidth Date Title of presentation 85
CAZAC sequence constellation diagram Constant Amplitude Zero Auto Correlation Date Title of presentation 86
Constellation Display (DL FDD, 10 MHz) I QPSK-modulated user data Date Title of presentation 87
Constellation Display (DL FDD, 10 MHz) II Reference signals in 1 st and 5 th OFDM symbol (Symbol #0 and #4) Date Title of presentation 88
Constellation Display (DL FDD, 10 MHz) III Secondary Synchronization Signal in 6th OFDM symbol (= symbol #5, RBPSK modulation) Primary Synchronization Signal in 7th OFDM symbol (= symbol #6, Zadoff-Chu-Sequence) Date Title of presentation 89
LTE Downlink: PCFICH The number of OFDM symbols used for control channel is variable TTI 마다바뀔수있음 CFI (Control Format Indication) <10 RB : 2~4 OFDMA symbols >10RB : 1~3 OFDMA symbols Information about the number of OFDM symbols (1~4) used for transmission of PDCCHs in a subframe PCFICH carries CFI Cell-specific scrambling prior to modulation 2 info bits Coding rate of 1/16 Number ofo bits = 32bits Modulation : QPSK Mapping to resource elements : 4REG (16 RE excluding RS) in the 1 st OFDM symbol Spread over the whole system bandwidth Same mapping for 1,2 and 4 antennas CFI 1 2 3 4 (Reserved) CFI codeword < b 0, b 1,, b 31 > <0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1> <1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0> <1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1> <0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0> 3GPP TS 36.212 / Table 5.3.4-1: CFI codew ords Date Title of presentation 90
LTE Downlink: PDCCH First n OFDM symbols <10 RB : 2~4 OFDMA symbols >10RB : 1~3 OFDMA symbols Scheduling assignment Transport format, resource allocation, HARQ info related to DL-SCH, PCH Transport format, resource allocation, HARQ info related to UL-SCH DPCCH format based on # of CCE (Control Channel Element = 9 REGs) used PDCCH format Number of CCEs Number of REGs Number of PDCCH bits 0 1 9 72 1 2 18 144 2 4 36 288 3 8 72 576 3GPP TS 36.211 / Table 6.8.1-1: Supported PDCCH formats Cell-specific scrambling, QPSK with tail-biting Conv. Code TX diversity, the same antenna ports as PBCH Mapped to REG no assigned to PCFICH or PHICH Date Title of presentation 91
LTE Downlink: PDCCH DCI transports downlink or uplink scheduling information, or uplink power control commands DCI Formats Description 0 1 1A 1B 1C 1D 2 2A 3 3A For the scheduling of PUSCH For the scheduling of one PDSCH codeword (SIMO, TxD) For the compact scheduling of one PDSCH codeword (SIMO, TxD) For the compact scheduling of one PDSCH codeword with precoding information (closed-loop single-rank) For very compact scheduling of one PDSCH codeword (paging, RACH response and dynamic BCCH scheduling) For the compact scheduling of one PDSCH codeword with precoding and power offset information For scheduling PDSCH to use configured in closed-loop SM For scheduling PDSCH to use configured in open-loop SM For the transmission of TPC commands for PUCCH and PUSCH with 2-bit power adjustment For the transmission of TPC commands for PUCCH and PUSCH with single bit power adjustment Date Title of presentation 92
PDCCH layer 1/2 control channel contents Uplink scheduling grant (DCI format 0) Hopping flag 1 bit Resource block assignment and hopping resource allocation Modulation and coding scheme, redundancy version 5 bits New data indicator 1 bit TPC command for scheduled PUSCH 2 bits Cyclic shift for demodulation reference signal 3 bits Uplink index for TDD - 2 bits CQI request 1 bit Date Title of presentation 93
PDCCH layer 1/2 control channel contents Downlink scheduling assignment (DCI format 2) Resource allocation header (allocation type 0 or 1) 1 bit Resource block assignment TPC command for PUCCH and persistent PUSCH 2 bits Downlink assignment index for TDD 2 bits Number of layers 2 bits HARQ process number 3 bits (FDD), 4 bits (TDD) Transport block to code word swap flag 1 bit Precoding information and confirmation For the first codeword: Modulation and coding scheme 5 bits New data indicator 1 bit Redundancy version 2 bits For the second codeword: Modulation and coding scheme 5 bits New data indicator 1 bit Redundancy version 2 bits Date Title of presentation 94
LTE Downlink: PHICH HARQ ACK/NACK in response to UL transmission PHICH group Multiple PHICHs mapped to the same set of REs (CDM & I/Q) HI codewords with length of 12 Res = 4 (spreading) X 3 (repetition) Orthogonal sequence : Walsh BPSK Modulation with I/Q multiplexing SF4 X I/Q = 8 PHICHs in normal CP SF4 X I/Q = 4 PHICHs in extended CP 3GPP TS36.811 / Table 6.9.1-2: Orthogonal sequences for PHICH Cell-specific scrambling TX diversity, the same antenna ports as PBCH 3 groups of 4 contiguous REs (not used for RS and PCFICH) HI 0 1 HI codeword < b 0, b 1, b 2 > < 0,0,0 > < 1,1,1 > 3GPP TS36.812 / Table 5.3.5-1: HI codew ords Date Title of presentation 95
LTE Downlink Configuration of physical broadcast channel Date Title of presentation 96
LTE downlink Scheduling of downlink data Check PDCCH for your UE ID. As soon as you are addressed, you will find all the information you need there. Physical Downlink Control Channel (PDCCH)? Physical Downlink Shared Channel (PDSCH) I would like to receive data on PDSCH but I don t know which resource blocks are allocated for me and how they look like Date Title of presentation 97
Physical Control Format Indicator Channel (PCFICH) Indicating PDCCH format Check PCFICH. It will tell you how many symbols (1, 2, or 3)in the beginning of the subframe are allocated for PDCCH. Physical Control Format Indicator Channel (PCFICH) Physical Downlink Control Channel (PDCCH) I would like to read the PDCCH but where is it?? Date Title of presentation 98
Physical Hybrid ARQ Indicator Channel (PHICH) Acknowledging uplink data packets Read the PHICH. It carries ACK or NACK for each single packet. Physical Hybrid ARQ Indicator Channel (PHICH) Physical Uplink Shared Channel (PUSCH) I have sent data packets on PUSCH but I don t know whether they have been received correctly.? Date Title of presentation 99
LTE Physical Layer: SC-FDMA in uplink Date Title of presentation 100
LTE Uplink: How to generate an SC-FDMA signal in theory? Coded symbol rate= R DFT Sub-carrier Mapping IFFT CP insertion N TX symbols Size-N TX Size-N FFT LTE provides QPSK,16QAM, and 64QAM as uplink modulation schemes Each subcarrier carries a portion of superposed DFT spread data symbols CAZAC (Constant Amplitude Zero Autocorrelation) sequence 사용 Ref. signal 및제어정보채널전송시각단말들의신호를구분하기위해 CDM 을수행하는경우, CAZAC sequence 를주로사용 CAZAC sequence 는 time/freq. domain 에서일정한 amplitude 를유지하는특성을가지므로단말의 PAPR 을낮추어커버리지를증가시키기에적합함 MU-MIMO 지원 Date Title of presentation 101
LTE Uplink: How does the SC-FDMA signal look like? In principle similar to OFDMA, BUT: In OFDMA, each sub-carrier only carries information related to one specific symbol In SC-FDMA, each sub-carrier contains information of ALL transmitted symbols Date Title of presentation 102
LTE uplink SC-FDMA time-frequency multiplexing Date Title of presentation 103
LTE Uplink: SC-FDMA parametrization for PUSCH and PUCCH, slot format One uplink slot, T slot 0 1 2 UL symb UL symb N 2 N 1 Modulation symbol a u N, U L symb 2 Date Title of presentation 104
LTE Uplink: Physical Channels in uplink Physical Uplink Shared Channel, PUSCH Uplink data with localized transmission (with/without hopping) Frequency hopping is available on both slot basis and subframe basis Physical Uplink Control Channel, PUCCH Carries HARQ ACK/NACK in response to DL transmission Carries Scheduling Request (SR), CQI, PMI and RI PUCCH transmission Physical Random Access Channel, PRACH Carries the random access preamble UCI transmission with PUSCH CQI/PMI is multiplexed with PUSCH and mapped into PUSCH bands ACK/NAK is multiplexed with PUSCH by punchuring the data RS would be transmitted through RRC Signalling (RAN2) UL Signal An uplink physical signal is used by the physical layer but does not carry information originating from higher layers UL RS (Uplink Reference Signal) for PUSCH, PUCCH UL Sounding RS not associated with PUSCH, PUCCH transmission Can t send PUSCH/PUSCCH at same time Date Title of presentation 105
LTE Uplink: Reference Signals DM RS Uplink channel estimation for uplink coherent demodulation/detection CAZAC sequence 로생성 Normal CP = 4 th symbol / Extended CP = 3 rd symbol Inter-cell Interference 를완화하기위해 Group hopping/sequence Hopping 적용 Group hopping : Base seq. group index값이 slot단위로변화 17개의 hopping pattern 마다 30개의 Group hopping Index (shift pattern) Seq. hopping : DM RS의길이가 5RB보다큰경우, 한 sub-frame 내에서 slot 단위로 Base seq. index간 hopping이이루어짐 Sounding RS uplink channel-quality estimation for better scheduling decisions PUxCH 와무관 SRS 전송주기 / 서브프레임 / 대역폭은각단말마다고유하게할당 ( 최소 4RB) SRS 는 subframe 의마지막 SC-FDMA symbol 로전송 Not used yet Date Title of presentation 106
LTE Uplink : Physical Uplink Control Channel (PUCCH) PUCCH is never transmitted simultaneously with PUSCH from the same UE Only needed when there is no PUSCH available Carries Uplink Control Information (UCI) in PUCCH or PUSCH Carries ACK/NACK, CQI, PMI, RI and SR (Scheduling Request) Symbol mapping of BPSK or QPSK 2 consecutive PUCCH slots in Time-Frequency Hopping at the slot boundary resource i resource j frequency resource j resource i 1 ms subframe Date Title of presentation 107
LTE Uplink Physical Uplink Control Channel (PUCCH) Date Title of presentation 108
LTE Uplink : PUSCH Frequency Hopping PUSCH Transmission 1 bit indication in UL grant whether frequency hopping or not (in DCI format=0 / hopping bit=1) Localized transmission w/o frequency hopping Frequency Selective Scheduling Gain Localized transmission with frequency hopping Frequency Diversity Gain, Inter-cell Interference Random ization Hopping based on the hopping information in UL grant (type 1 according to hopping bits) Hopping according to a predefined hopping pattern (type 2 - according to hopping pattern) Transmission and hopping modes are given from UL scheduling grant Inter subframe / Intra subframe PUSCH hopping (related to UE mobility) Set of PRBs (for PUSCH) to be used for transmission are given by scheduling grant If hopping w ith predefined hopping pattern is enabled, a predefined pattern is used together When grant is absent, e.g., in cases of persistent scheduling and HARQ retransmission, UE follows the indication for hopping mode in the initial grant (with RACH) A single bit signalled by higher layer indicates whether PUSCH frequency hopping is inter-subframe only or both intra and inter-subframe Date Title of presentation 109
LTE Uplink Physical Uplink Shared Channel (PUSCH) Demodulation pilot signal 50 resource blocks in 10 MHz Screenshot of R&S SMU200A signal generator Date Title of presentation 110
LTE Uplink: Resource allocation Date Title of presentation 111
LTE Uplink: Random Access Procedure Higher layers indicate position of random access in frequency/time domain Date Title of presentation 112
LTE Uplink : Random access preamble PRACH 는 RA 과정에서단말이기지국으로전송하는 Preamble 6RB를차지하며 subcarrier는 1.25KHz (Format #4는 7.5KHz) Sequence 부분은길이 839의 ZC sequence로구성 (Format#4는길이 139) 5 types of preamble formats (Higher layers control the preamble format/configuration) TCP TSEQ PRACH configuration 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 System frame number Even Even Even Any Any Any Any Any Any Any Any Any Any Any Any Even Subframe number 1 4 7 1 4 7 1, 6 2,7 3, 8 1, 4, 7 2, 5, 8 3, 6, 9 0, 2, 4, 6, 8 1, 3, 5, 7, 9 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 9 Date Title of presentation 113
LTE Protocol Architecture Basic Date Title of presentation 114
Summary of layers Packet Date Convergence Protocol compression of redundant protocol control information(tcp/ip, RTP/UDP/IP headers) Transfer of user data(pdcp SDU from NAS) to RLC support of losless relocation of SRNS Broadcast/Multicast Control Protocol Storage of Cell Broadcast Messages. Traffic volume monitoring and radio resource request for CBS. Scheduling of BMC messages. Transmission of BMC messages to UE. Delivery of Cell Broadcast messages to upper layer (NAS) Date Title of presentation 115
WCDMA/HSPA HSDPA HSUPA UE Node-B RNC UE Node-B RNC Date Title of presentation 116
User plane Header compression (ROHC) In-sequence delivery at handover Duplicate detection Ciphering for user/control plane Integrity protection for control plane Timer based SDU discard in Uplink AM, UM, TM ARQ (Re-)segmentation Concatenation In-sequence delivery Duplicate detection SDU discard Reset Mapping between logical and transport channels (De)-Multiplexing Traffic volume measurements HARQ Priority handling Transport format selection PDCP = Packet Data Convergence Protocol RLC = Radio Link Control MAC = Medium Access Control PHY = Physical Layer SDU = Service Data Unit (H)ARQ = (Hybrid) Automatic Repeat Request Date Title of presentation 117
Control plane Broadcast Paging RRC connection setup Radio Bearer Control Mobility functions UE measurement control EPS bearer management Authentication ECM_IDLE mobility handling Paging origination in ECM_IDLE Security control EPS = Evolved packet system RRC = Radio Resource Control NAS = Non Access Stratum ECM = EPS Connection Management Date Title of presentation 118
LTE Protocol Architecture User and Control Plane Date Title of presentation 119
E-UTRA Logical Channel Transport Channel Downlink Uplink Rel. 6 BCCH BCH PCCH PCH CCCH FACH DCCH DCH DTCH CTCH HS-DSCH MBMS CHs RACH CCCH DCH DCCH E-DCH DTCH BCH PCH DL-SCH MCH RACH UL-SCH LTE BCCH PCCH CCCH DCCH DTCH MBMS-CHs CCCH DCCH DTCH Date Title of presentation 120
LTE channels CCCH DCCH DTCH UL logical channels RACH UL-SCH UL transport channels UL physical channels PRACH PUCCH PUSCH Date Title of presentation 121
LTE Protocol Architecture Reduced complexity l Reduced number of transport channels l Shared channels instead of dedicated channels l Reduction of Medium Access Control (MAC) entities l Streamlined concepts for broadcast / multicast (MBMS) l No inter enodeb soft handover in downlink/uplink l No compressed mode l Reduction of RRC states Date Title of presentation 122
Initial access procedure UE Random ID enb Sent on UL-SCH; includes NAS UE identifier and RRC CONNECTION REQUEST 1 Random Access Preamble Random Access Response 2 Sent on DL-SCH; assignment of Temporary C-RNTI and initial uplink grant 3 Scheduled Transmission Contention Resolution 4 Sent on DL-SCH; addressed to Temporary C-RNTI (early contention resolution) Date Title of presentation 123
RRC Connection Establishment UE EUTRAN RRC CONNECTION REQUEST RRC CONNECTION SETUP RRC CONNECTION SETUP COMPLETE Date Title of presentation 124
Initial context establishment Date Title of presentation 125
LTE measurements Date Title of presentation 126
LTE RF Testing Aspects UE requirements according to 3GPP 36.521/523 Transmitter Characteristics: Maximum output power Frequency error Output power dynamics (power control, transmit on/off power, ) Output RF spectrum emissions (occupied bandwidth, out of band emissions, spectrum emisssion maks, ACLR, ) Transmit intermodulation Modulation quality, EVM Receiver characteristics: Reference sensitivity level Maximum input level Adjacent channel selectivity Blocking characteristics Spurious response Intermodulation characteristics Spurious emissions Performance TR 36.803: User Equipment (UE) radio transmission and reception Date Title of presentation 127
There will be enough topics for future trainings Thank you for your attention! Comments and questions welcome! Date Title of presentation 128