Ltetutorialfemtoforumpart1 130814003455 phpapp02

Page 1

Marius Pesavento - marius.pesavento@mimoOn.de Willem Mulder - willem.mulder@mimoOn.de

LTE Tutorial part 1 LTE Basics

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

Š mimoOn

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Agenda 

Part 1, LTE Basics      

Introduction to LTE FDD/TDD frame structures and reference signals Physical channels, logical channels PHY signal processing architecture H-ARQ processing, H-ARQ timing UE categories

Part 2, Advanced topics in LTE       

9:30 – 10:30

11:00 – 12:30

The LTE MIMO modes Codebook-based precoding Closed loop operation CQI reporting modes Using antenna port 5 (SDMA) techniques Simulation results Outlook LTE Advanced

Q&A

12:30 – 13:00

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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3G Evolution

SPRING 2011

HSPA evolution  Gradually improved performance at low additional cost in 5MHz spectrum allocation  Next step: dual carrier allocation (10MHz) LTE  LTE is new Radio Access Network (RAN)  significantly improved performance in up to 20MHz allocation  Peak data rates up to 300Mbps LTE-Advanced  natural evolution of LTE, next major step  toward IMT-Advanced  support spectrum aggregation up to 100MHz and data rate up to 1Gbps

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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LTE Targets  Cell-capacity (Control plane): 200 user per cell in 5MHz  Peak data rate  DL: 300MBit/s  UL: 75 MBit/s

   

Control plane latency: 50/100ms (idle to active) User Plane Latency: <5ms (unload condition) Interworking with UMTS, WCDMA, GSM/EDGE Access technology:  OFDMA in DL  SC-FDMA in UL (reduced PAPR)

 Basis antenna configuration:  eNB: Tx 1 to 4; Rx ≥ 1  UE: Tx = 1; Rx ≥ 2 (depending on UE category )

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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E-UTRA frequency bands E-UTRA Band

UMTS band

extension band

1

Uplink (UL) eNode B receive UE transmit

Downlink (DL) eNode B transmit UE receive

UL-DL Band separation

FUL_low – FUL_high

FDL_low – FDL_high

FDL_low-FUL_high

1920 MHz

1980 MHz

Duplex Mode

2110 MHz

2170 MHz

130 MHz

FDD FDD FDD

2

1850 MHz

1910 MHz

1930 MHz

1990 MHz

20 MHz

3

1710 MHz

1785 MHz

1805 MHz

1880 MHz

20 MHz

4

1710 MHz

1755 MHz

2110 MHz

2155 MHz

355 MHz

FDD

5

824 MHz

849 MHz

869 MHz

894MHz

20 MHz

FDD

6

830 MHz

840 MHz

875 MHz

885 MHz

35 MHz

FDD

7

2500 MHz

2570 MHz

2620 MHz

2690 MHz

50 MHz

FDD

8

880 MHz

915 MHz

925 MHz

960 MHz

10 MHz

FDD

9

1749.9MHz

1784.9 MHz

10

1710 MHz

1770 MHz

11

1427.9MH z [TBD]

1452.9 MHz

[TBD]

12

1844.9MHz

1879.9 MHz

2110 MHz

2170 MHz

1475.9MHz

1500.9 MHz

[TBD]

[TBD]

60 MHz

FDD

340 MHz

FDD

23 MHz

FDD

[TBD]

FDD

13

777 MHz

787 MHz

746 MHz

756 MHz

21

FDD

14

788 MHz

798 MHz

758 MHz

768 MHz

20

FDD

33

1900 MHz

1920 MHz

1900 MHz

1920 MHz

N/A

TDD

34

2010 MHz

2025 MHz

2010 MHz

2025 MHz

N/A

TDD

...

35

1850 MHz

1910 MHz

1850 MHz

1910 MHz

N/A

TDD

36

1930 MHz

1990 MHz

1930 MHz

1990 MHz

N/A

TDD

37

1910 MHz

1930 MHz

1910 MHz

1930 MHz

N/A

TDD

38

2570 MHz

2620 MHz

2570 MHz

2620 MHz

N/A

TDD

39

1880 MHz

-

1920 MHz

1880 MHz

-

1920 MHz

N/A

TDD

40

2300 MHz

-

2400 MHz

2300 MHz

-

2400 MHz

N/A

TDD

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Basic Transmission Schemes

Transmission Bandwidth

1.4 MHz

Sampling Frequency

1.92 MHz

FFT Size

128

256

6

15

#RBs (12 subcarrier)

3 MHz

5 MHz

10 MHz

15 MHz

20 MHz

15.36 MHz

23.04 MHz

30.72 MHz

512

1024

1536

2048

25

50

75

100 (110)

3.84 MHz 7.68 MHz

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Frame Structure Type 1 Frame Structure Type 1 one radio frame, Tf = 307200*TS = 10 ms one slot, Tslot = 15360*TS = 0.5 ms #0

#1

one subframe Transmission Time Interval (TTI)= 1ms

#2

#3

#18 TS

#19

basic time unit corresponding to sampling frequency 30.72MHz

frame structure type 1 is applicable to FDD (frequency division duplex), full-duplex and half-duplex

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Slot Structure normal cyclic prefix 160*TS

2048*TS

144*TS

2048*TS

144*TS

2048*TS

144*TS

2048*TS

144*TS

2048*TS

144*TS

2048*TS

144*TS

#0

2048*TS

#6 slot

normal cyclic prefix #1

normal cyclic prefix #2

extended cyclic prefix, ∆f = 15 KHz 512*TS

2048*TS

512*TS

2048*TS

512*TS

2048*TS

512*TS

2048*TS

512*TS

2048*TS

512*TS

#0

2048*TS

#5 slot extended cyclic prefix

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Frame Structure Type 2: TDD Downlink subframe

Uplink subframe

Special guard subframe for DL to UL switch

Uplink or Downlink subframe

Special guard subframe or Downlink SF

one radio frame, Tf = 307200*TS = 10 ms DL #0

S #1

subframe 1 ms

UL #2

UL/DL #3

special subframe: DL to UL switching S #1 or #6

UL/DL #4

DL #5

S/DL #6

UL/DL #7

UL/DL #8

UL/DL #9

DwPTS: DL pilot time slot shortend DL subframe (3,8,9,10,11, or 12 OFDM symbols) reference signals, primary sync and control, PDSCH

DwPTS PSS

SSS

RS and Control

GP: Guard period (1,2,3,4,7,8,9,10 OFDM symbols)

GP UpPTS

UpPTS: UL pilot time slot (1 or 2 OFDM symbols) sounding reference or RACH

0 1 2

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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DL

GP

DwPTS

Tx

UpPTS

Frame Structure Type 2: TDD

UL Tx #2

UL Tx #3 UL/DL switching must be accomplished within the CP length (e.g. if path delay is zero)

UpPTS UpPTS

DL Tx #0

GP

DwPTS

Tx

DL

DwPTS

Rx

GP

path delay

UL Rx #2

UL Rx #3 DL Tx #4

DL Tx #5

DL Tx #6

UpPTS

DL

GP

Rx

DwPTS

path delay

DL Rx #4

DL Rx #5

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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DL Rx #6

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DwPTS, GP, UpPTS length (in OFDM symbols) Format

Normal CP DwPTS

GP

Extended CP UpPTS DwPTS

GP

UpPTS

8

0

3

10

3

666.7µs  200Km

1

9

4

8

3

2

10

3

9

2

3

11

2

10

1

4

12

1

3

7

5

3

9

8

2

6

9

3

9

1

7

10

2

-

-

-

8

11

1

-

-

-

© mimoOn

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1

2

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

1

2


Resource Blocks resource block DL N RB − 1

7 OFDM symbols

DC

all subframes

frame structure 1 normal cyclic prefix

12 subcarriers

∆f = 15 KHz resource block 0

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Physical Channels Downlink (DL)  Physical Broadcast Channel (PBCH)  System Information (Master Information Block MIB) approx. every 40 ms  Physical Downlink Control Channel (PDCCH)  DL Control Information Format (DCI-format), DLgrants (current TTI), UL-grants (+4 TTI), uplink power control  Physical DL Shared Channel (PDSCH)  DL transport blocks (TBs), DL Control Information, System Information Block (SIB), Paging Channel (PCH), Multicast Channel (MCH)  Physical Control Format Indicator Channel (PCFICH)  location of the PDCCH  Physical Hybrid ARQ Indicator Channel (PHICH)  UL ACK/NACK  Physical Multicast Channel (PMCH) Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Physical Channels Uplink (UL)  Physical Random Access Channel (PRACH)  UL timing estimation (path delay), UL scheduling request (SR)  Physical Uplink Control Channel (PUCCH)  Channel Quality Indicater (CQI), Precoding Matrix Indicator (PMI), Rank Indicator (RI), ACK/NACK, SR  Physical Uplink Shared Channel (PUSCH)  UL TBs, ACK/NACK, CQI, PMI, RI, SR

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PHY Signals Downlink  Primary and Secondary Synchronization Signal  cell-search, DL-frame synchronization, time, frequency, drift,

 Cell-specific reference signals (antenna port 0 - 3), orthogonal (non-overlapping) in time-frequency-domain  MIMO channel estimation, fine frequency estimation, UL-CQI estimation

 UE-specific reference signals  implicit signaling of DL-transmit beamforming weights

Uplink  Demodulaton Reference Signal  Sounding Reference Signal  UL wideband CQI estimation

 Random-Access Sequence  for UL timing synchronization

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Cell-Specific Reference Signals Tx Port 0

Tx

Port 1

Port 0

two antenna ports (frame structure 1, normal cyclic prefix)

one antenna port (frame structure 1, normal cyclic prefix)

reference signal 0 reference signal 1

reference signal 0

slot

carrier frequency: 2.6GHz LTE requirement max speed: 350km/h max Doppler frequency: 843Hz Clarke's model coherence time: T > 9/(16π fm) approx. 3 OFDM symbols

not used for transmission on this antenna port

slot

slot

pilot spacing in frequency coherence bandwidth B ≥ 6x15KHz B ¼ 1 / (2 π τ) ⇒delay spead τ : τ ¼ 1 / (2 π B) =1.77µsec (¼ 54 smpls; corresp. to 531 meter )

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Cell-Specific Reference Signals Tx Port 0 Port 1 Port 2 Port 3

four antenna ports (frame structure 1, normal cyclic prefix) reference signal 0 reference signal 1 reference signal 2 reference signal 3 slot

slot

even slot odd slot

even slot odd slot

not used for transmission on this antenna port

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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DL time-frequency structure •DL payload on DL Shared Channel •Primary synchronization signal •Secondary synchronization signal •Broadcast Channel •DL Control Channel •Reference signal

20MHz

30.72MHz

guard band

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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UL time-frequency structure

frequency

demodulation reference signal (DRS) sounding reference signal (SRS) PUSCH PUCCH

time / OFDM symbol number Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Modulation

Scrambling

HARQ Support & Rate Matching •HARQ hard buffer for S1, P1, P2 • Subblock interleaver •Rate Matcher, RVs

CB Concatenation

Channel Coding Turbo

CB CRC

CB Segmentation

MAC PDU

TB CRC

PDSCH Tx

number of Transport Blocks (TBs)

number of streams MIMO Precoding

number of antennas

Layer Mapping P/S Sync Signals

Ref Signal

IFFT

CP Adding

to DACs

Pulse Shape

Frame Builder

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PDSCH Rx Layer Demapper

antenna ports

MIMO Detector

Measurements

Channel Estimation

P/S-Sync Processing

Turbo Decoder

CB CRC

CB Concatenation

MAC PDU

TB CRC

Downsampling filter

frame/RB demapper

HARQ Support & Rate Matching: •HARQ soft buffer for S1, P1, P2, •Subblock interleaver •Soft-Combiner 8 bit, RVs

smple drift Rotator Samp.D.

other CWs

Fine Frequency estimation

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

Soft Demodulator 8 bit

FFT

Descrambling

CP Removal

CB sementation: transition from OFDM wise to CB-wise processing

Rotator Freq. Off.

From ADCs

© mimoOn

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PUSCH Tx CQI and/or PMI report CQI <= 11 bit

32bit

Length 32 block code

to reduce PAPR

RB Resource Mapper

Modulation

number of Transport Blocks (TBs) of different users

Demod. Ref. Signal

Transform Precoding Mixed-Radix DFT

Scrambling

HARQ Support & Rate Matching •HARQ hard buffer for S1, P1, P2 • Subblock interleaver •Rate Matcher, RVs

Channel Interleaving

Rate Matching

Data & Control Mux

Channel Conv. Coding Channel Turbo Coding

control TS36.212Figure 5.2.2-1

CB Concatenation

CB CRC

CB Segmentation

TB CRC

MAC PDU

CB CRC

ACK RI CQI and/or PMI report CQI > 11 bit

Rotator Samp. Drift

IFFT

CP Adding

Rotator Freq. Cor.

Pulse Shape

DAC

Sound. Ref. Signal

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PUSCH Rx Frame timing

CP Removal

FFT

frame/RB Demapper

Measurements

MultiAntenna Receiver

Demod. Ref. Channel Estimation

Tranform (De)Precoding (mixed-Radix DFT)

Sounding Ref. Processing Rate DeMatching: •Subblock interleaver •Soft-Combiner 8 bit, RVs

Data & Control Demux

HARQ Support & Rate Matching: •HARQ soft buffer for S1, P1, P2, •Subblock interleaver •Soft-Combiner 8 bit, RVs

CB Segmentation: Transition from OFDM- to CB-wise processing

Turbo Decoder

CB CRC

CB Concatenation

MAC PDU

TB CRC

Block decoder control (32,11) TS36.212Figure 5.2.2-1

ACK

RI

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

Descrambling

Viterbi

Channel deinterleaver

CB CRC

© mimoOn

Soft demodulator 8.bit

From ADCs

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Downlink Control Indicator Format (DCI format)        

DCI format 0 is used for the transmission of UL-SCH assignments DCI format 1 is used for the transmission of DL-SCH assignments for single antenna operation DCI format 1A is used for a compact transmission of DL-SCH assignments for single antenna operation DCI format 1B is used to support closed-loop single-rank transmission with possibly contiguous resource allocation DCI format 1C is for downlink transmission of paging, RACH response and dynamic BCCH scheduling DCI format 2 is used for the transmission of DL-SCH assignments for MIMO operation DCI format 3 is used for the transmission of TPC commands for PUCCH and PUSCH with 2-bit power adjustments DCI format 3A is used for the transmission of TPC commands for PUCCH and PUSCH with single bit power adjustments

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PDCCH processing chain other DCIs DCI User specific search space (aggregation level) 1-CCE (2x6attempts) 2-CCE (2x6attempts) 4-CCE (2x2attempts), 8-CCE (2x2attempts) Cell specific search space (aggregation level) 4-CCE (2x4attempts) 8-CCE (2x2attempts)

DCI

CRC generation L=16

CRC scrambling with RNTI / (UE Tx port) specific

tail bit convolutional encoder, rate 1/3

other DL channels

Resource Mapper, (mapping to RE groups) time first – then frequency

IFFT and CP attachment

code bit extraction CRC calculation CRC extraction

PDCCH multiplexing

interleaver, rate-matching

<NIL>element insertion

antenna ports 0,...,3 layer mapping, pre-coding: single antenna port or transmit diversity

sub-block interleaver (on quadruples of modulated symbols), remove <NULL> elements

MIMO channel

FFT and CP removal, frequency and timing correction

Resource demapper (1-3 OFDM symbols, according to CFI)

Viterbi decoder

ratedematching, deinterleaving

44 blind decoding attempts (commonand UE-specificsearch-space),

QPSK modulation

sub-block de-interleaver

cell specific descrambling

cell-specific scrambling

equalizer, MIMO detector, (requires channel estimation)

softdemodulator

44 PDCCH candidates XOR

RNTI

skip some decodes if RNTI is found

RNTI: radio network temporary identifier Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PUCCH processing chain Tx all formats (2) N RB

(2) resource index nPUCCH

Pseudo-Random sequence generator

N cs(1)

determines cyclic shift α

cell ncs (ns , l )

cell cinit = N ID

never simultaneously with PUSCH

ACK/NACK (1a,1b) 1 or 2 bit

20bit

to map on CQI resource concatenation: •only CQI (2: 20 bit) •CQI + ACK/NACK (2a: 21 bit, 2b: 22bit)

for mapping to outer RBs

UE specific cell specific scrambling

to map on ACK/NACK resource ACK/NACK w/o CQI or SR, 1a: d(0)= 1,-1 1b: d(0)= 1,j,-1,-j

Scheduling request (SR) (presence/absence)

to map on SR resource •w/o ACK/NACK (1);d(0)=1 •w ACK/NACK d(0) = 1,-1 d(0) = 1,j,-1,-j

12 symbols

Block code Length 20

modulation: d(0),…d(19) on QPSK spreading (BPSK) with 36.211, 7.1 “d” sequence d(20), d(21) ru(,αv ) (n) Resourcem according to apper 36.211, Table PUCCH N seq = 12 “z” (k,l,slot#) 5.4.2-1 IFFT

for mapping to in RBs

spreading with sequence ru(,αv ) (n) PUCCH N seq = 12

12 symbols

CQI, PMI, RI report (2) <= 4bit

include demodulation reference signals for format 2 (see below)

CP attach

spreading with orthogonal sequence wnoc (i ) PUCCH N SF =4

(1) resource index nPUCCH

include demodulation reference signals for format 1 (see below)

determines cyclic shift and orthogonal sequence

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PUCCH processing Rx format 2, 2a, 2b

determines cyclic shift α multiplication with conjugate of ru(,αv ) (n) PUCCH N seq = 12

Resource de-mapper (k,l,slot#)

format 1,1a,1b ACK/NCK w or w/o SR (see next page) multiplication with conjugate of ru(,αv ) (n) PUCCH N seq = 12

matched filtering with tap M coef. vector

user m

IDFT length 12

CP removal FFT (2048)

separate user m users according to cyclic shift in timedomain

channel estimation separate users according to cyclic shift in timedomain tap M(<12) channel coefficient vector

(2) resource index nPUCCH

M depends on number of shifts in use

determines cyclic shift α

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

hard demodulator

QPSK IDFT length 12

format 2,2a,2b (CQI,PMI,RI)

(2) resource index nPUCCH

UE specific cell specific descrambling

segmentation SR •w/o ACK/NACK (1);d(0)=1 •w ACK/NACK d(0) = 1,-1 d(0) = 1,j,-1,-j

Block decoding (bit-level matched filter)

ACK/NACK (1a,1b)

CQI, PMI, RI report (2)

© mimoOn

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PUCCH processing Rx (2) resource index nPUCCH

PUCCH N seq = 12

CP removal FFT (2048)

Resource de-mapper (k,l,slot#)

format 2,2a,2b (CQI,PMI,RI) channel estimation 1 multiplication with conjugate of ru(,αv ) (n) PUCCH N seq = 12

resource

(2) index nPUCCH

determines cyclic shift α

IDFT length 12

on SR resource

separate users according to cyclic shift in time-domain tap M(<12) channel coefficient vector M depends on number of shifts in use

matched filtering with tap M coef. vector

hard demodulator

ru(,αv ) (n)

separate user m users according to cyclic shift in timedomain

UE specific cell specific descrambling

user m

channel estimation2 separate users according to orthogonal cover sequence (despreading)

multiplication with conjugate of

despreading separate usere according to orthogonal sequence

determines cyclic shift α

IDFT length 12

format 1,1a,1b (SR and ACK/NACK)

format 1

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

SR

© mimoOn

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ACK/NACK


PUCCH processing Rx

PUCCH N seq = 12

Resource de-mapper (k,l,slot#) on ACK/NACK resource

format 2,2a,2b (CQI,PMI,RI) channel estimation 1 multiplication with conjugate of ru(,αv ) (n) PUCCH N seq = 12

resource

(2) index nPUCCH

determines cyclic shift α

UE specific cell specific descrambling

user m

IDFT length 12

CP removal FFT (2048)

matched filtering with tap M coef. vector

hard demodulator

ru(,αv ) (n)

separate user m users according to cyclic shift in timedomain

separate users according to cyclic shift in time-domain tap M(<12) channel coefficient vector M depends on number of shifts in use

channel estimation2 separate users according to orthogonal cover sequence (despreading)

multiplication with conjugate of

despreading separate usere according to orthogonal sequence

(2) resource index nPUCCH determines cyclic shift α

IDFT length 12

format 1,1a,1b (SR and ACK/NACK)

format 1a, 1b

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

ACK/NACK

© mimoOn

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Demodulation reference signals for PUCCH format 2 N cs(1)

Pseudo-Random sequence generator

(2) resource index nPUCCH

cell ncs (ns , l )

determines cyclic shift α

cell cinit = N ID

input sequence for format 1

for mapping to outer RBs

modulation: d(0),…d(19) on QPSK 36.211, 7.1 d(20), d(21) according to 36.211, Table 5.4.2-1

UE specific cell specific scrambling

spreading with sequence ru(,αv ) (n) PUCCH N seq = 12

12 symbols

(2) N RB

Resourcem apper (k,l,slot#)

input sequence for format 2

for mapping to in RBs

spreading with sequence ru(,αv ) (n) PUCCH N seq = 12

12 symbols

IFFT CP attach

spreading with orthogonal sequence wnoc (i ) PUCCH N SF =4

(1) resource index nPUCCH

determines cyclic shift and orthogonal sequence

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PHICH

(DL HARQ) Selection depends on the index of the first RB of the corresponding PUSCH transmission

ACK/NACK 3x 1 bit repetition

BPSK (I or Q)

12 symbols

symbol level Spreading, length 4 orthogonal sequence

Max. 8 different sequences

super-position of different ACK/NACKS

Location depends on the index of the first RB of the corresponding PUSCH transmission

12 symbols

3bit

3 symbols

scrambling

layer mapper SISO or MIMO TD

other ACK/NACK 1 bit

resource mapper, PHICH group is mapped to 3 groups of 4 REs

FFT / CP insertion

MIMO channel ACK/NACK 1 bit other ACK/NACK 1 bit

matched filter length(12)

descrambling

MIMO detector

resource demapper

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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CP removal/IFFT

31


PBCH MIB CRC attach CRC mask

antenna config

tail bit convolutional encoder, rate 1/3

MIMO channel

PBCH carries important PHY information: system bandwidth, number of transmit antennas, PHICH configuration and system frame number,‌

interleaver, rate-matching

cell specific scrambling

scrambling

QPSK modulation

IFFT CP inclusion

resource mapping

precoding SFD

layer mapping for single antenna or transmit diversity

frame no 0,1,2,3

channel estimates CP removel FFT

Equalization (SISO, MISO, or TD)

soft demodulator (QPSK)

rate matching buffer

Viterbi decoder

MIB

After successful reception of PBCH, UE can read D-BCH in PDSCH (including PCFICH and PDCCH) which carries system information not including in PBCH

antenna config

XOR

code bit extraction, CRC masked computation CRC mask

CRC extaction

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PRACH RACH sequence extends over several slots Zadoff-Chu sequence (L=839), selectec from set of 64 sequences), different root-sequences or different cyclic shifts, Create in 839 sequence in frequency domain

Zero padding to 1024

possible cell specific root-sequences,(conjugate)

Multiplication

DFT 1024

decimation 1/24

IDFT of length 1024

Upsampling by 24, LP filtering

Rotator, frequency shift

CP inclusion (3168, 21024, 6240)

UL Tx signal in time domain: PUSCH, PUCCH,DRS,SRS, including CP

add to OFDM frame in time domain

LP filter 1/24

phase rotation, (mixing,frequency shift to DC)

Channel

correlation (convolution) in time domain replaced by multiplication in frequency domain

IDFT 1024 (results in change of sampling rate)

Peak dection, path delay estimation

RACH sequence, associated timing-advance

RACH sequence, associated timing-advance

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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PCFICH

DL Control Format power control

2 bits block code L=16

scambling cell and subframe dependent

modulator QPSK

layer mapping

precoding SISO or Tx diversity

power boosting

cell ID

resource mapper (4 blocks of 4REs = 1RE group)

FFT / CP insertion

MIMO channel

number of OFDM symbols reserve for control 1,2,3

block detection

descrambling

demodulator

MIMO detection

resource demap

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

CP removalII FFT

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Rate matching and HARQ processing write-in row-wise

sub-block interleaver

systematic parity 1 parity 2

RV1 S1

RV0

column permutation

read-out column-wise

S1

RV2

P1 P2 MUX

P1/P2

RV3 Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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HARQ timing

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UE Categories  

synchronous HARQ in UL, ACK/NACK in 4 TTI after UL reception, re-transmission (UL) in 8 TTI after initial transmission, total of 8 HARQ processes asynchronous HARQ in DL, ACK/NACK in 4 TTI after DL reception, retransmission with DL scheduling grant, total number of 8 HARQ processes

Downlink physical layer parameter values set by UE Category Maximum number of DL-SCH transport block bits received within a TTI

Maximum number of bits of a DL-SCH transport block received within a TTI

Total number of soft channel bits

Maximum number of supported layers for spatial multiplexing in DL

Category 1

10296

10296

250368

1

Category 2

51024

51024

1237248

2

Category 3

102048

75376

1237248

2

Category 4

150752

75376

1827072

2

Category 5

302752

151376

3667200

4

UE Category

Uplink physical layer parameter values set by UE Category UE Category

Maximum number of bits of an UL-SCH transport block transmitted within a TTI

Support for 64QAM in UL

Category 1

5160

No

Category 2

25456

No

Category 3

51024

No

Category 4

51024

No

Category 5

75376

Yes

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

≈ 8HARQ buffer x(3(S1,P1,P2)x10296+ 12(termination))

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UE Categories

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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TDD:

DL grants and ACK/NACK reporting  FDD: only one DL (and one UL) grant per TTI. Corresponding DL TBs need to be ACK/NACK 4 TTIs after reception (1 or 2 bits).  TDD: ACK/NACK required for detected PDSCH and for DL SPS release on PDCCH.  TDD: usually one DL grant (but up to 2 DL grants, in special case of UL-DL config. 0) can be received within one TTI.

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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TDD ACK/NACK

Recall: Frame Structure Type 2: TDD Downlink subframe

Uplink subframe

Special guard subframe for DL to UL switch

Uplink or Downlink subframe

Special guard subframe or Downlink SF

one radio frame, Tf = 307200*TS = 10 ms DL #0

S #1

subframe 1 ms

UL #2

UL/DL #3

special subframe: DL to UL switching S #1 or #6

UL/DL #4

DL #5

S/DL #6

UL/DL #7

UL/DL #8

UL/DL #9

DwPTS: DL pilot time slot shortend DL subframe (3,8,9,10,11, or 12 OFDM symbols) reference signals, primary sync and control, PDSCH

DwPTS PSS

SSS

RS and Control

GP: Guard period (1,2,3,4,7,8,9,10 OFDM symbols)

GP UpPTS

UpPTS: UL pilot time slot (1 or 2 OFDM symbols) sounding reference or RACH

0 1 2

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TDD: UE ACK/NACK procedure (PUSCH transmission and PHICH reception) UE Rx Perspective

UE Tx Perspective

•ACK/NACK received on PHICH in subframe i •for UL transmission in subframe i - k, where the values for k are given in the table.

•for UL transmission in subframe i, •ACK/NACK received on PHICH in subframe i + k, where the values for k are given in the table. k for TDD configurartion 0-6

k for TDD configurartion 0-6 TDD UL/DL Configuration 0

subframe number i 0

1

6,7

4

1

3

4

5 6,7

4

2 3

2

6

6 7

8

9

4 4

6

6 6

subframe number i 0 1 2 3 4 5 6 7 8 9

0

4 7 6

4 7 6

1

4 6

4 6

2

6

6

6

6

3

6 6 6

4

6

6

4

6 6

5

6

5

6

6

4 6 6

6

6

TDD UL/DL Configuration

6

4

7

4

6

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

© mimoOn

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DL control issues in TDD DL HARQ UE Rx Perspective

UE Tx Perspective

•reception of PDSCH in subframe n •ACK/NACK on PUSCH or PUCCH in subframe n + k

•ACK/NACK on PUSCH or PUCCH in subframe n •for reception of PDSCH insubframe n - k

k for TDD configurartion 0-6

k for TDD configurartion 0-6

DL subframe number n

TDD UL/DL Config.

0

1

0

4

6

1

7

6

2

7

6

3

4

11

4

12

11

5

12

11

6

7

7

2

3

4

9

4

5

6

4

6

4

7

6

8

7

6

7

6

8

7

8

7

8

9

TDD UL/DL Config.

DL subframe number n 0

1

2

3

0

6

4

1

7,6

4

8

2

8,7,4,6

6

5

5

3

7,6,11

6,5

7

6

5

4

4

12,8,7,11

6,5,4,7

7

6

5

4

13

5

13,12,9,8,7,5,4,11

7

7

5

6

7

4

5

6

7

4

8

6

4

7,6

4 4

8,7,4,6

7

5,4

5

7

Multiple ACK/NACK in one subframe: Requieres ACK/NACK bundling (logical AND of codewords) or ACK/NACK multiplexing.

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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9

7


TDD: Downlink Assignment Index DAI to prevent ACK/NACK errors due to bundling k‘ for TDD configurartion 0-6 and DAI in DCI format 0 (UL assignments) TDD UL/DL Config.

DL subframe number n 0

1

2

0

DAI

6

1

DAI

6

4

4

DAI

4

4

4

4

4

5

4

2 3

6

DAI

DAI

DAI

7

3

4

5

6

7

4

DAI

6

DAI

DAI

6

4

4

DAI

4

8

9 4

•DAI indicates the number of subframes with PDSCH receptions and SPS releases detected within n-k and n (k 2 K) that need to be bundeled in the UL ACK/NACK signaling. •DAI is used only for TDD

DAI

DAI

DAI

DAI

DAI

DAI 7

5

DAI

DAI

7

7

DAI

k for TDD configurartion 0-6 and DAI in DCI formats 1/1A/1B/1D/2/2A (DL) TDD UL/DL Config.

DL subframe number n 0

1

2

0

DAI

DAI

6

1

DAI

3

7,6

4

8,7,4,6

DAI

7,6,11

6,5

4

12,8,7,11

6,5,4,7

5

13,12,9,8,7,5,4,11

2 3

6

DAI

DAI

DAI

7

4

5

6

7

4

DAI

DAI

6

DAI

5,4

DAI

8

4

7,6

4

8,7,4,6

DAI

DAI

9

DAI

DAI

DAI

DAI DAI

7

5

DAI

DAI

7

7

DAI

DAI MSB, LSB

UL DL VDAI or V DAI

Number of subframes with PDSCH transmission

0,0

1

1 or 5 or 9

0,1

2

2 or 6

1,0

3

3 or 7

1,1

4

0 or 4 or 8

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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End of Part 1

Thank you!!!

Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK

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Backup slides

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3GPP LTE roadmap

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