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WCDMA Air Interface Training Part 4 WCDMA Physical Layer

WCDMA Air Interface Training Part 4 WCDMA Physical Layer. WCDMA (ETSI/ARIB/3GPP). WCDMA Overview 3GPP Standards Organization, 3GPP Document Structure WCDMA Frequency Allocations WCDMA Performance Overview Physical Implementation WCDMA Network Overview Downlink Implementation

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WCDMA Air Interface Training Part 4 WCDMA Physical Layer

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  1. WCDMA Air Interface TrainingPart 4 WCDMA Physical Layer

  2. WCDMA(ETSI/ARIB/3GPP) • WCDMA • Overview • 3GPP Standards Organization, 3GPP Document Structure • WCDMA Frequency Allocations • WCDMA Performance Overview • Physical Implementation • WCDMA Network Overview • Downlink Implementation • Uplink Implementation • Physical Layer Procedures • Slot, Frame, and Superframe Synchronization • Random Access Procedures • Packet Channel Access • Establishment of a Dedicated Channel • Soft Handover • Hard Handover / Compressed Mode Operation • TDD Implementation

  3. WCDMA(ETSI/ARIB/3GPP) • Third Generation Partnership Project (3GPP) 3GPP Project Coordination Group(ETSI, ARIB, T1) TSG-RAN TSG-CN TSG-T TSG-SS WG 1Layer 1 WG 1MM/CC/SM WG 1Services WG 1MS Testing WG 2Layers 2,3 WG 2CAMEL/MAP WG 2Architecture WG 2MS Services WG 3Iub, Iur, IuUTRAN, O&M WG 3Interworking WG 3Security WG 3USIM WG 4Codec WG 4BS TestingProtocol WG 5Telecom

  4. WCDMA(ETSI/ARIB/3GPP) • Specifications referenced in this presentation • WCDMA UTRAN Network • 3GPP TS 25.401-v330: UTRAN Overall Description • 3GPP TS 25.832-v300: Manifestations of Handover and SRNS Relocation • 3GPP TS 26.071-v301: AMR Speech Codec; General Description • WCDMA Radio Transmission and Resource Management • 3GPP TS 25.101-v331: UE Radio Transmission and Reception (FDD) • 3GPP TS 25.104-v330: BS Radio Transmission and Reception (FDD) • 3GPP TS 25.103-v200: RF Parameters in Support of Radio Resource Management • 3GPP TS 25.133-v310: Requirements for Support of Radio Resource Management • WCDMA Physical Layer Specifications (FDD and TDD) • 3GPP TS 25.201-v310: Physical Layer General Description • 3GPP TS 25.301-v350: Radio Interface Protocol Architecture • 3GPP TS 25.302-v350: Services Provided by the Physical Layer • WCDMA FDD, TDD Mode Standards:3GPP TS 25.211-v330: Physical channels and mapping of transport channels onto physical channels (FDD) • 3GPP TS 25.212-v330: Multiplexing and channel coding (FDD) • 3GPP TS 25.213-v330: Spreading and modulation (FDD) • 3GPP TS 25.214-v330: Physical layer procedures (FDD)3GPP TS 25.215-v330: Physical layer - Measurements (FDD) • 3GPP TS 25.221-v330: Physical channels and mapping of transport channels onto physical channels (TDD) • 3GPP TS 25.222-v331: Multiplexing and channel coding (TDD) • 3GPP TS 25.223-v330: Spreading and modulation (TDD) • 3GPP TS 25.224-v330: Physical layer procedures (TDD) • 3GPP TS 25.225-v330: Physical layer - Measurements (TDD) This presentation iscurrent as of TS-25 V3.3.0(3GPP June 2000 Release)

  5. WCDMA(ETSI/ARIB/3GPP) • 3GPP WCDMA Overview • Both FDD (2x 5 MHz) and TDD (1x 5 MHz)modes supported • Operation specified in bands between 1850 and 2170 MHz • BS time synchronization not required for FDD mode • GPS not required • Fast Synchronization Codes allow asynchronous operation and handover • Synchronous operation is allowed; allows faster acquisition, interference reduction • Multi-Code and Variable Spreading Factor modes supported • Network interface compatible with GSM - MAP / GPRS • * To be made compatible with ANSI-41 per OHG requirement • Physical Parameters: • Chip rate = 3.840 Mcps • RF Bandwidth = 5 MHz • Physical Layer data rates of 15, 30, 60, 120, 240, 480, 960, and 1920 kb/sec • Payload data rates of 12.2, 64, 144, 384, 768, and 2048 kb/sec • Frame length = 10 mSec • Fast Power Control: Bi-directional; 1500 updates/sec

  6. WCDMA Frequency Allocations WCDMA /EUROPE TDD FDD UPLINK TDD FDD DOWNLINK 1900 2010 1980 2025 2110 1920 2170 WCDMA / USA FDD UPLINK TDD FDD DOWNLINK 3GPP TS 25.201 ¶ 5.2, 25.102 ¶ 5.2.2 1990 1850 1910 1930 IMT-2000 MSS MSS IMT-2000 MSS MSS ITU/WARC-95 1885 1980 2010 2025 2110 2160 2170 2200 DECT IMT-2000 MSS IMT-2000 MSS Europe 1900 2010 1880 1980 2025 2110 2170 2200 PHS IMT-2000 MSS Terrestrial MSS Japan 1885 1895 1918.1 1980 2010 2025 2110 2170 2200 CDMA FDD WLL TDD WLL CDMA FDD WLL MSS MSS China 1865 1880 1900 1920 1945 1960 1980 2010 2025 2110 2170 2200 A D B E F C A D B E F C MSS BroadcastAuxiliary Reserved MSS USA 1850 1910 1930 1990 2025 2110 2150 2185 2200

  7. GSM/GPRS Network Architecture To other BTS’s To other BSC’s To other MSC’s Um AC EIR Abis Base Station Subsystem(BSS) A E F External Networks PSTN ISDN Internet ... H F Um Base Transceiver Station (BTS) BaseStationController(BSC) MobileSwitchingCenter(MSC) Gateway MSC E Abis A B C C B VLR HLR VLR Um Abis A D D G To other BTS’s To other BSC’s External Data Network IP / X.25 PacketControlUnit(PCU) Serving GPRSService Node (SGSN) Gateway GPRSService Node (GGSN) GPRS NetworkComponents

  8. WCDMA/UMTS Network Architecture

  9. UMTS and the UTRAN 3GPP TS 25.401 ¶ 6.0 GSM/GPRS Core Network (CN) PSTNISDNInternet MSC GPRSService Node Iu Iu Iu Iu RNS RNS Iur UTRAN (UMTS Terrestrial Radio Access Network) RNC RNC Iub Iub Iub Iub Node B Node B Node B Node B Uu User Equipment(UE)

  10. UMTS and the UTRAN 3GPP TS 25.401 ¶ 3.0 • UTRAN Definitions • RNS (Radio Network Subsystem) • A full or partial network offering access between UE and Core Network • Contains one RNC • RNC (Radio Network Controller) • Element of the RNS that controls physical radio resources • Node B • Logical Node controlling transmission and reception from one or more cells • Uu Interface • Interface between UE and Node B • Iu Interface • Interface between CN and RNS • Iur Interface • Interface between one RNS and another RNS • Iub Interface • Interface between RNC and Node B

  11. UMTS and the UTRAN 3GPP TS 25.401 ¶ 7.1 • UTRAN Operational Functions (partial) • Functions related to overall system access control • Admission Control, Congestion Control • System information broadcasting • Radio channel ciphering and deciphering • Functions related to mobility • Handover • SRNS Relocation • Functions related to radio resource management and control • Initial (random) access detection and handling • Radio resource configuration and operation • combining/splitting control • Radio bearer connection set-up and release (Radio Bearer Control) • Allocation and deallocation of Radio Bearers • Radio protocols function • RF power control • Radio channel coding • Radio channel decoding

  12. UTRAN Model 3GPP TS 25.201 ¶ 4.0 • UTRAN OSI Model Radio Resource Control (RRC) Layer 3 Logical channels - grouped by information content - User Data - Control and signaling Layer 2 Medium Access Control (MAC) Transport channels - grouped by method of transport Physical layer Layer 1 Physical channelsPhysical Channels Distinguished by: - RF Frequency - Channelization Code - Spreading Code - Modulation (I/Q) Phase (uplink) - Timeslot (TDD mode) Direct RRC control of the physical layer Air Interface

  13. Physical Layer Requirements 3GPP TS 25.201 ¶ 4.1.2 , 25.301¶ 5.2.2 • Services provided by Physical Layer • Data and RF Processing Functions • FEC encoding/decoding of transport channels • Error detection on transport channels and indication to higher layers • Rate matching of coded transport channels to physical channels • Power weighting and combining of physical channels • Closed-loop power control • Modulation/demodulation and spreading/de-spreading of physical channels • Multiplexing/de-multiplexing of coded composite transport channels • Mapping of transport channels on physical channels • Macrodiversity distribution/combining • Operational Functions • Cell search functions • Synchronization (chip, bit, slot, and frame synchronization) • Soft Handover support • Radio characteristics measurements including FER, SIR, Interference Power, etc., and indication to higher layers • Uplink timing advance (TDD mode)

  14. Channels broadcast to all UE in the cell P-CCPCH- Primary Common Control Physical ChannelSCH - Sync Channel P-CPICH - Primary Common Pilot ChannelS-CPICH - Secondary Common Pilot Channel(s) Paging Channels S-CCPCH - Secondary Common Control Physical Channel PICH - Page Indication Channel Random Access and Packet Access Channels PRACH - Physical Random Access Channel AICH - Acquisition Indication Channel PCPCH - Common Physical Packet Channel AP-AICH - Acquisition Preamble Indication Channel CD/CA-AICH - Collision Detection Indication Channel CSICH - CPCH Status Indication Channel Dedicated Connection Channels DPDCH - Dedicated Physical Data Channel DPCCH - Dedicated Physical Control Channel F-PDSCH - Physical Downlink Shared Channel WCDMA Physical Channels BaseStation (BS) UserEquipment (UE)

  15. WCDMA Downlink Physical Channels 3GPP TS 25.211 • Common Downlink Physical Channels • P-CCPCH Common Control Physical Channel (Primary) - Broadcasts cell site information - Broadcasts cell SFN; Timing reference for all DL channels • SCH Synchronization Channel - Fast Synch. codes 1 and 2; time-multiplexed with P-CCPCH • S-CCPCH Common Control Physical Channel (Secondary) - Transmits idle-mode signaling and control information to UE’s • P-CIPCH Common Pilot Channel • S-CIPCH Secondary Common Pilot Channel (for sectored cells) • PDSCH Physical Downlink Shared Channel - Transmits high-speed data to multiple users • Dedicated Downlink Physical Channels • DPDCH Dedicated Downlink Physical Data Channel • DPCCH Dedicated Downlink Physical Control Channel- Transmits connection-mode signaling and control to UE’s

  16. WCDMA Downlink Physical Channels 3GPP TS 25.211 • Downlink Indication Channels • AICH (Acquisition Indication Channel) • Acknowledges that BS has acquired a UE Random Access attempt • (Echoes the UE’s Random Access signature) • PICH (Page Indication Channel) • Informs a UE to monitor the next paging frame • AP-AICH (Access Preamble Indication Channel • Acknowledges that BS has acquired a UE Packet Access attempt • (Echoes the UE’s Packet Access signature) • CD/CA-ICH • Confirms that there is no ambiguity between UE in a Packet Access attempt • (Echoes the UE’s Packet Access Collision Detection signature) • Optionally provides available Packet channel assignments • CSICH • Broadcasts status information regarding packet channel availability

  17. WCDMA Uplink Physical Channels 3GPP TS 25.211 • Uplink Physical Channels • Common Uplink Physical Channels • PRACH Physical Random Access Channel - Used by UE to initiate access to BS • PCPCH Physical Common Packet Channel - Used by UE to send connectionless packet data • Dedicated Uplink Physical Channels • DPDCH Dedicated Uplink Physical Data Channel • DPCCH Dedicated Uplink Physical Control Channel- Transmits connection-mode signaling and control to BS

  18. WCDMA Code Types • Channelization Codes (Orthogonal Codes) • Used to orthogonally code different data channels from BS, UE • Scrambling Codes (Spread Spectrum Codes) • BS Scrambling Codes: Used by UE to distinguish the desired BS • UE Scrambling Codes: Used by BS to distinguish the desired UE • Synchronization Codes • Primary Sync. Code: Fixed 256-bit code Helps UE identify the presence of a WCDMA BS Helps UE achieve Slot Synchronization • Secondary Sync. Codes: Group of 256-bit codes Helps UE achieve Frame Synchronization • Pilot Codes • A full-time common Pilot (CPICH) provides coherent reference for UE receiver • Pilot data bits are embedded into each timeslot of the Dedicated Data Channel • Random Access Preamble Codes • Preamble Signatures; Used by BS to distinguish between UE making access attempts • Preamble Scrambling Codes; Used to identify which BS is being accessed

  19. WCDMA Downlink Physical Layer

  20. WCDMA Downlink (FDD)

  21. Downlink Logical Channels 3GPP TS 25.301¶ 5.3.1.1 • Common Downlink Logical Channels • BCCH (Broadcast Control Channel) • Broadcasts cell site and system identification to all UE • PCCH (Paging Control Channel) • Transmits paging information to a UE when the UE’s location is unknown • CCCH (Common Control Channel) • Transmits control information to a UE when there is no RRC Connection • SHCCH (Shared Channel Control Channel) • Control channel associated with shared traffic channels (TDD mode only) • CTCH (Common Traffic Channel) • Traffic channel for sending traffic to a group of UE’s. • Dedicated Downlink Logical Channels • DCCH (Dedicated Control Channel) • Transmits control information to a UE when there is a RRC Connection • DTCH (Dedicated Traffic Channel) • Traffic channel dedicated to one UE

  22. Downlink Transport Channels 3GPP TS 25.301¶ 5.2.1.1 • Common Downlink Transport Channels • BCH (Broadcast Channel) • Continuous transmission of system and cell information • PCH (Paging Channel) • Carries control information to UE when location is unknown • Pending activity indicated by the PICH (paging indication channel) • FACH (Forward Access Channel) • Used for transmission of idle-mode control information to a UE • No closed-loop power control • DSCH (Downlink Shared Channel) • Carries dedicated control and/or traffic data; shared by several UE’s • Dedicated Downlink Transport Channels • DCH (Dedicated Channel) • Carries dedicated traffic and control data to one UE

  23. OVSF Codes 3GPP TS 25.201 ¶ 4.3 • Downlink OVSF Channelization Codes C4,0 1 1 1 1 C2,0 C4,1 1 1 C1,0 1 1 -1 -1 1 C4,2 1 -1 1 -1 C2,1 C4,3 1 -1 1 -1 -1 1 SF = 1 SF = 2 SF = 4 Designation: cch, SF , code number

  24. Code Layering 3GPP TS 25.201 ¶ 4.2.1, 4.2.3 • WCDMA Code Layering

  25. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 Frame = 15 slots = 10 mSec If transmit diversity is used, then the pilot symbols are as shown for each antenna: Antenna 1Symbols A A A A A A A A A A A A A A A A A A A A A A A A A Antenna 2Symbols A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -A A A -A Slot 14 Slot 0 Slot 1 Common Pilot Channel 3GPP TS 25.211¶ 5.3.3 • Downlink CPICH (Common Pilot Channel) 1 timeslot = 2560 Chips = 10 symbols = 20 bits = 666.667 uSec Pilot Symbol Data (10 symbols per slot)

  26. Sync Channel / Primary Common Control Channel 3GPP TS 25.211¶ 5.3.3.2 • Downlink SCH / P-CCPCH BCH Spreading Factor = 2561 Slot = 0.666 mSec = 18 BCH data bits / slot SCH BCH 256 Chips 2304 Chips Broadcast Data (18 bits) PSC SSCi 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 Frame = 15 slots = 10 mSec

  27. Secondary Common Control Channel 3GPP TS 25.211¶ 5.3.3.2 • Downlink S-CCPCH Spreading Factor = 256 to 41 Slot = 0.666 mSec = 2560 chips = 20 * 2k data bits; k = [0..6] 0, 8, or 16 bits 0, 2, or 8 bits 20 to 1256 bits TFCI or DTX Data Pilot 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 Frame = 15 slots = 10 mSec

  28. Page Indication Channel 3GPP TS 25.211¶ 5.3.3.9 • Paging Indication Channel (PICH) • Spread with SF=256 Channelization code • Each UE looks for a particular PICH time slot • A paging indicator set to “1” indicates that the UE should read the S-CCPCH of the corresponding frame. 288 bits for paging indication 12 bits (undefined) b0 b1 b287 b288 b299 One radio frame (10 ms)

  29. Dedicated Control/Data Channel 3GPP TS 25.211¶ 5.3.2 • Downlink DPCCH/DPDCH Frame 1 Slot = 0.666 mSec = 2560 chips = 10 x 2^k bits, k = [0...7]SF = 512/2k = [512, 256, 128, 64, 32, 16, 8, 4] DPDCH DPCCH DPDCH DPCCH Data 1 TPC TFCI Data 2 Pilot 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 Frame = 15 slots = 10 mSec The DPDCH carries user traffic, layer 2 overhead bits, and layer 3 signaling data.The DPCCH carries layer 1 control bits: Pilot, TPC, and TFCI Downlink Closed-Loop Power Control steps of 1 dB, 0.5 dB

  30. Downlink Data Rates • Variable Data Rates on the Downlink: Examples Channel Coding(OVSF codes at 3.84 Mcps) S/P Converter Coded Data1.920 Mb/sec (19,200 bits per 10 mSec frame) 960 kb/sec

  31. Downlink DPDCH/DPCCH Slot Formats 3GPP TS 25.211¶ 5.3.2 Notes: 1) Zero-TFCI slot formats are used when there is only one data service on the DCH. 2) Slot formats A and B are used during compressed mode operation

  32. Time-Embedded Pilot Symbols 3GPP TS 25.211¶ 5.3.2 • DL: Time-multiplexed with DPDCH • UL: Transmitted on Q-channel along with TPC, TFCI, FBI bits Pilot Bit Patterns, Downlink DPDCH (Data Channel) Note: Shaded portions are the Frame Synchronization Words (FSW)

  33. Transmit Power Control (TPC) Bits 3GPP TS 25.211¶ Table 13 • TPC Bits • 2, 4, or 8 bits per slot depending on slot format

  34. MUX MUX TFCI Bits • TFCI (Transport Format Combination Indicator) • Used when multiple services are multiplexed onto one DPDCH Data Channel 1 Channel Coding TFI 1 Data Channel 2 Channel Coding TFI 2 Coded Composite Transport Channel (CCTrCH) Data Channel N Channel Coding TFI N TFCI Word32 bits 10 bits Channel Coding TFI: Transport Format IndicatorTFCI: Transport Format Combination Indicator

  35. 344 76 344 76 344 76 344 76 12 28 28 12 12 28 28 12 12 28 28 28 12 12 12 28 12 12 28 12 28 28 12 28 12 28 12 28 28 12 28 12 28 28 12 12 12 28 28 12 Downlink Data Coding, Multiplexing 3GPP TS 25.101 App. A.3 Traffic @ 12.2 kbps L3 Data @ 2.4 kbps Layer 3 Control data Traffic data (122x2) 244 96 CRC16 CRC 16 Add CRC bits 244 96 Add CRC bits Tail 8 Tail 8 Add Tail bits 260 112 Add Tail bits Conv. Coding R=1/3 804 360 Conv. Coding R=1/3 Rate matching 688 304 Rate matching 1st interleaving 688 304 1st interleaving Data from second 244-bit packet #1 344 #2 344 #1 344 #2 344 #1 76 #2 76 #3 76 #4 76 Radio FrameSegmentation 2nd interleaving 420 420 420 420 slot segmentation MUX: Pilot, TPC, TFCI 30 ksps DPCH 600 bits (300 symbols) 600 bits (300 symbols) 600 bits (300 symbols) 600 bits (300 symbols) Radio frame FN=4N Radio frame FN=4N+1 Radio frame FN=4N+2 Radio frame FN=4N+3

  36. 9050 70 9050 70 9050 70 9050 70 608 608 608 608 608 608 608 608 608 608 608 608 32 32 32 32 32 32 32 32 32 32 32 32 Downlink Data Coding, Multiplexing 3GPP TS 25.101 App. A.3 Traffic @ 384 kbps L3 Data @ 2.4 kbps 3840 3840 Traffic data (3840x2) Layer 3 Control data 96 CRC16 CRC 16 CRC16 Add CRC bits 3840 96 Add CRC bits 3840 Tail 8 Concatenate 7712 112 Concatenate Terminationbits Conv. Coding R=1/3 360 Turbo Coding R=1/3 11568 12 11568 12 Rate matching 18100 280 Rate matching 1st interleaving 18100 280 1st interleaving Data from second 3840-bit packet #1 9050 #2 9050 #1 9050 #2 9050 #1 70 #2 70 #3 70 #4 70 Radio FrameSegmentation 2nd interleaving 9120 9120 9120 9120 slot segmentation MUX: Pilot, TPC, TFCI 480 ksps DPCH 9600 bits (4800 symb.) 9600 bits (4800 symb.) 9600 bits (4800 symb.) 9600 bits (4800 symb.) Radio frame FN=4N Radio frame FN=4N+1 Radio frame FN=4N+2 Radio frame FN=4N+3

  37. Data 1 TPC TFCI Data 2 Pilot Data 3 Data 4 AdditionalDPCCH/DPDCH Data N-1 Data N AdditionalDPCCH/DPDCH Multi-Code Transmission 3GPP TS 25.211¶ 5.3.2 • Downlink DPCCH/DPDCH Frame 1 Slot = 0.666 mSec = 2560 chips = 10 x 2^k bits, k = [0...7] PrimaryDPCCH/DPDCH

  38. Downlink Shared Channel 3GPP TS 25.211¶ 5.3.3.5 • Downlink PDSCH Frame 1 Slot = 0.666 mSec = 2560 chips = 20 x 2^k bits, k = [0...6]SF = [256, 128, 64, 32, 16, 8, or 4] Data (30 kbps to 1920 kbps) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 Frame = 15 slots = 10 mSec Notes: The PDSCH has no embedded Pilot, TFCI, or TPC. Therefore, it must always be associated with an active DPCCH. The associated DPCCH provides the necessary Pilot, TFCI, and TPC bits for the PDSCH. The PDSCH can change its spreading ratio every frame, as indicated by the TFCI on the DPCCH Any orthogonal code under the “PDSCH Root Channelization Code” may be utilized Multiple PDSCH’s may be assigned to one UE

  39. CRC Algorithms 3GPP TS 25.212¶ 4.2.1.1 • CRC Algorithms • 0, 8, 12, 16, or 24 parity bits (determined by upper layers) • g(CRC24) = D24 + D23 + D6 + D5 + D + 1 • g(CRC16) = D16 + D12 + D5 + 1 • g(CRC12) = D12 + D11 + D3 + D2 + D + 1 • g(CRC8) = D8 + D7 + D4 + D3 + D + 1

  40. FEC Coding Rules 3GPP TS 25.212¶ 4.2.3 • FEC Coding

  41. WCDMA Convolutional Code Generators 3GPP TS 25.212¶ 4.2.3.1 Rate 1/2, k=9 coder: G0 = 5618 , G1 = 7538 Data In D D D D D D D D 2:1MUX DataOut Rate 1/3 , k=9 coder: G0 = 5578 , G1 = 6638 , G2 = 7118 Data In D D D D D D D D 3:1MUX DataOut

  42. WCDMA Turbo Code Generator 3GPP TS 25.212¶ 4.2.3.2 Xk MUX Zk Data InRate = X Xk D D D Data Out 3x input bits + 12 Termination bits TurboInterleaver Z’k D D D X’k At end of data block, both switches go “down” to provide 12-bit Trellis Termination: [ xK+1, zK+1, xK+2, zK+2, xK+3, zK+3, x'K+1, z'K+1, x'K+2, z'K+2, x'K+3, z'K+3 ]

  43. Interleaving 3GPP TS 25.212 ¶ 4.2.5 , 4.2.11 • Interleaving • 1st-Stage Interleaver • Performed prior to service multiplexing • Interleaving depth of 1, 2, 4, or 8 columns • 2nd-Stage Interleaver • Performed after service multiplexing • Interleaving depth of 30 columns

  44. Permute MatrixColumns Interleaving 3GPP TS 25.212 ¶ 4.2.5 , 4.2.11 • Interleaving (‘K’ blocks containing (R x C) bits each) Before Interleaving 0, 1, 2, 3, - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - , (RC - 1) 0 C • • (R-1)C 1 C+1 • • (R-1)(C+1) - - - - - - m C+m • • (R-1)(C+m) - - - - - - C-1 2C-1 • • RC-1 Write Data into MatrixRow-wise C0 C1 - - - Cm - - - CC-1 0 C • • (R-1)C m C+m • • (R-1)(C+m) 1 C+1 • • (R-1)(C+1) C-1 2C-1 • • RC-1 Read Data from MatrixColumn-wise C0 Cm C1 CF-1 After Interleaving 0, C, … , (R-1)C , m, C+m, … (R-1)(C+m) , … , 1, C+1 , (R-1)(C+1), .., C-1 , 2C-1 , … RC-1

  45. Interleaving • Interleaver Columns Permutations (1st and 2nd Interleavers)

  46. Rate Matching 3GPP TS 25.212 ¶ 4.2.7 • Rate Matching • When coded data rates of services are incompatible, “Rate Matching” is used to equalize the data rates. • Rate Matching may be performed by: • Padding with extra bits • Puncturing of bits using a pseudo-random algorithm • For complete rate matching rules, see 3GPP TS25.212 ¶4.2.7

  47. Downlink Orthogonal Code Allocations • Each data stream is assigned a unique Channelization Code • - User voice / data channels • - Layer 3+ Control Channel data • Primary CPICH (Common Pilot) uses Channelization Code C256,0 • - One per cell • - Phase reference for SCH, Primary CCPCH, AICH, PICH • - Scrambled using the Primary Scrambling Code • Secondary CPICH uses any Channelization code of SF=256 • - Zero, one, or several per cell • - Scrambled using the Primary or Secondary Scrambling Code • P-CCPCH (Broadcast Channel) always uses Code C256,1 • S-CCPCH Channelization Code is broadcast over the P-CCPCH • Traffic Channel Codes are transmitted over the S-CCPCH

  48.   Complex PN Spreading 3GPP TS 25.212 ¶ 5 • Complex PN Spreading (Downlink) cos ( 2fRFt) SC-I Is I FIR Filter RFOutput SC-Q FIR Filter Q Qs SC-I sin ( 2fRFt)

  49. Complex PN Spreading • Complex PN Spreading (Downlink): The way it looks in the spec 3GPP TS 25.212 ¶ 4.2.5 , 4.2.11 ScramblingCode (Cscram)SCI + jSCQ Cos(wt) p(t) I Real (•) RF Out + + Imag (•) p(t) Q *j I+jQ -Sin(wt) Same result as in the previous slide:

  50. PSC PSC PSC Antenna 1 SSCi SSCi SSCi PSC PSC Antenna 2 SSCi SSCi Slot #0 Slot #1 Slot #2 Slot #3 Slot #14 b0 b1 b2 b3 Antenna 1 Data bits b0 b1 b2 b3 -b2 b3 b0 -b1 Antenna 2 BS Transmit Diversity 3GPP TS 25.211 ¶ 5.3 • TSTD (Time-Switched Transmit Diversity); SCH Only • STTD (Space-Time Transmit Diversity); All Other DL Channels Note: TSTD and STTD must be supported by the UE, but are optional in BS

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