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
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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
-
-
-
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1
2
Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK
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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
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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
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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 â&#x20AC;&#x201C; 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)
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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
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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
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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
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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,â&#x20AC;Ś
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
Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK
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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
Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK
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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
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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
Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK
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3GPP LTE roadmap
Marius Pesavento, Willem Mulder, Femto Forum Plenary, June 2010, Reading, UK
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