New Radio (NR)
- Architecture and PHY layer aspects
HUAWEI Wireless Standard
2019-03-08
HUAWEI TECHNOLOGIES CO., LTD.
www.huawei.com
Outline
•
5G General aspects
•
Usage scenarios and performance targets
•
New Radio Architecture
•
New Radio Physical layer
•
•
Waveform
•
Numerology and frame structure
•
Modulation
•
Channel coding
•
Reference signals
Milimeter Wave MIMO
•
MIMO transmission
•
Beam management
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5G usage scenarios and performance targets
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5G – a broader wireless eco system
① Diversified service
Peak Data
Rate
10Gbps
mMTC
eMBB
1M devices/km2
② New market opportunities
uRLLC
Latency
1ms
③ New roles & new revenue streams
Integrator
Vertical
Device
B2C  B2HB2V
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Operator
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Going Beyond MBB: Some Evolution Some Revolution
User Experience
IoT
Services Enhanced by 5G
1. Personal
Communication
5G Initial Phase
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2. Massive IoT
Mission Critical
Services Enabled by 5G
3. Critical IoT
4. Human-Machine
Interaction
5G Advanced Phase
IMT-2020 vs. IMT-Advanced
• The Recommendation ITU-R M-2083.0 suggests the following relative
performance improvements for ‘5G’ over ‘4G’
100
90
80
70
60
50
40
30
20
10
0
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Performance targets
eMBB
UL: 10 Gbps
DL: 20 Gbps
Peak Data
Rate
(Gbit/s)
User Experienced
Data Rate (5% UE tput)
(Mbit/s)
30/15 bps/Hz
Dense urban:
DL: 100 Mbps
UL: 50 Mbps
IMT-2020
Area Traffic
Capacity
(Mbit/s/m2 )
Indoor:
DL: 10 Mbps/m2
Network
Energy
Efficiency
Spectrum
Efficiency
DL: 30 bps/Hz
UL: 15 bps/Hz
IMTAdvanced
Mobility
(km/h)
500 km/h
1M devices/km2
Connection Density
(devices/km 2 )
User Plane DL/UL: 0.5 ms
Latency
URLLC
mMTC
1M devices/km2
99.999% reliability
@ 1ms
Source: Recommendation ITU-R. M.2083
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Usage scenarios for NR in 3GPP
•
•
•
The 3GPP RAN specification* TS38.913 defines the following usage scenarios
•
eMBB (enhanced Mobile BroadBand)
•
URLLC (Ultra-Reliable and Low Latency Communications)
•
mMTC (massive Machine Type Communications)
Deployment scenarios further include
•
eV2X (enhanced Vehicle-to-Everything)
•
Satellite extension to terrestrial
•
Unlicensed spectrum
The 3GPP SA specification TS22.261 defines requirements on the whole system
•
Performance requirements for
•
High data rates and traffic densities
•
Low latency and high reliability
•
Virtual Reality
•
High accuracy positioning
*Specifications available at http://www.3gpp.org/ftp/Specs/archive
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URLLC service examples
• Discrete automation – motion control
› E.g., motion control of robots, machine tools, as well as packaging and printing machines
› Closed-loop control; small message (56 bytes), cycle time 2 ms, 99,9999% reliability
• Discrete automation
› E.g., production that result in discrete products: cars, chocolate bars
› Open-loop control; latency 10 ms – 1 s, 99,99% reliability
Smart
Factories
• Process automation
› E.g., production of bulk products such as petrol and reactive gases, remote control
• Electricity distribution
• Intelligent transport systems – infrastructure backhaul
› Connected Vehicles
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Connected
Car
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Smart
Grid
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New Radio Architecture
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Terminology
• Radio Access Network (RAN)
• Scheduling, transmission protocols, mobility, PHY layer ...
• Core Network (CN)
• Charging, authentication, end-to-end connetions ...
• LTE: Evolved Packet Core (EPC)
• NR: 5GCN
• 5GCN is based on EPC with further enhancements
• Network slicing
• Control-plane/user-plane split
• Service based architecture
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Enhancements in the 5GCN
• Networks are becoming virtualized
• Service based architecture
• Specifications focus on services more than network nodes
• Network slicing
• A set of functions from the service based architecture
• E.g., one slice for eMBB, one slice for industry-automation
• Slices use the same RAN and 5GCN
• Control-plane/user-plane separation (CUPS)
• Less latency: select proper User nodes without increasing Control
node
• Increase data traffic: add User nodes without addin Control nodes
• Locate and scale User and Control nodes independently
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As Is: Fully meshed networking
MME
CG
PCRF
OCS
…
To Be: Cloud + Distributed DC
MME
CG
PCRF
Central DC
Mesh
GW-C
GW-C
GW-C
GW-C
…
GW-U
GW-U
GW-U
GW-U
…
…
Tree
Local DC
…
DGW
(GW-U)
RGW
(GW-U)
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OSS
CGW
(GW-C)
Edge DC
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OCS
CDN
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…
DGW
(GW-U)
RGW
(GW-U)
APP
Server
…
NSA (Non Standalone)
SA (Standalone)
EPC
EPC
S1
LTE
NG-C
S1
LTE
5G NR
NG CORE
5G NR
Control plane
User plane
•
Focus on eMBB/FWA
•
LTE as anchor, reuse current EPC,
Control plane
User plane
•
eMBB/uRLLC/mMTC and network
slicing
5G NR quick introduction
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NG-U
•
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New Core required
Page 15
Rel-15 supported NR
architectures
Opt.7 – Non-standalone,
LTE-Assisted with NGCN
NextGen Core
Opt.3 – Non-standalone
LTE-Assisted with EPC
EPC
LTE
eLTE
Opt.2 – Standalone NR with NGCN
NR
NextGen Core
NR
Opt.4 – standalone NR with
NGCN; LTE as SeNB
NR
NextGen Core
NR
Phase1.1(2017.12)
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Phase1.3(2018.12)
Phase1.2(2018.6)
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eLTE
Page 16
Physical layer
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Key NR design principles and features
Forward
compatibility
Reserved
resources
Sync Signal
Config Ctrl BW
Config RS BW
Flexible frame
structure
Large BW
m-MIMO
High spectral
utilization
mmWave
Carrier
aggregation
LDPC
Mini-slot
scheduling
DL pre-emption
UL grant free
Flex frame
structure
High data rate
Low latency
High reliability
Front-loaded
DMRS
Fast UE
processing time
DL ctrl with high
aggregation level
Data duplication
Data channel slot
aggregation
Large coverage
UL ctrl channel
slot aggregation
Polar
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Multi-beam
LTE/NR co-ex
UL power control
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Low PAPR WF &
modulation
Item
LTE
NR R15 (Phase I)
Frequency band
Sub 6GHz
Sub-6 GHz, mmWave (up to 52.6 GHz)
Maximum Bandwidth (per CC)
20 MHz
50 MHz (@ 15 kHz), 100 MHz (@ 30 kHz),
200 MHz (@ 60 kHz), 400 MHz (@120 kHz)
Minimum Bandwidth (per CC)
1.4MHz
5MHz
Spectrum Utilization
90%
Up to 98%
Maximum CCs
5 (Rel.10) / 32 (Rel.12).
Current implementation is 5.
16 (allowed BW and CCs combinations TBD)
Duplexing
FDD, Static TDD
FDD, Static TDD, Dynamic TDD
Waveform
CP-OFDM for DL; SC-FDMA for UL
CP-OFDM for DL; CP-OFDM and DFT-s-OFDM for UL
Modulation
Up to 256 QAM DL (moving to 1024 QAM);
Up to 64 QAM UL
Up to 256 QAM UL & DL;
pi/2 BPSK with FDSS for DFT-s-OFDM
Subcarrier spacing
15KHz
2^n · 15 kHz TDM and FDM multiplexing
Maximum number of subcarriers
1200
3300
Subframe length
1 ms (moving to 0.5 ms)
1 ms
Slot length
7 symbols in 0.5ms
14 symbols (duration depends on subcarrier spacing)
2, 4 and 7 symbols for mini-slots
Self-contained subframe
Not supported
Supported
Multi-numerology multiplexing
Not supported
Supported
Channel coding
Turbo Code (data); TBCC (control)
LDPC (data); Polar Codes (control & PBCH)
RS
Cell Specific RS & UE Specific DMRS
Front-loaded DMRS (UE-specific)
Air interface latency
10 ms (moving to 5 ms)
1 ms
MIMO
SU: up to 8 layers for DL; up to 4 layers for UL (current implementation is 1 or 2 layers)
MU: up to 8 layers (4 orthogonal only)
SU: up to 8 layers for DL; up to 4 layers for UL
MU: up to 12 orthogonal layers
CW
1 or 2
1 or 2
Initial Access
No beamforming
Beamforming
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Frequency domain
CP-OFDM
Data
S/P
IFFT
CP
Time domain
D/A
High PAPR
Low PAPR
DFT-s-OFDM (SC-FDMA)
S/P
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DFT
IFFT
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CP
D/A
Page 20
Waveform
• Spectrally confined waveform for up to 52.6 GHz
• Downlink: CP-OFDM
• Uplink: both CP-OFDM and DFT-s-OFDM are mandatory to UEs
• CP-OFDM for single- and multi-layer transmission
• DFT-s-OFDM only for single layer transmission, targeting coverage limited
scenarios
• Better spectrum utilization (larger than 90% of LTE) and localization
• Reduced guard band between contiguous carriers
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High spectral utilization
< 6GHz
SCS
15kHz
30kHz
60kHz
5MHz
10MHz
15MHz
20MHz
25MHz
30MHz
40MHz
50MHz
60MHz
80MHz
100MH
z
25
52
79
106
133
160
216
270
N/A
N/A
N/A
90%
93.6%
94.8%
95.4%
95.8%
96%
97.2%
97.2%
11
24
38
51
65
78
106
133
162
217
273
79.2%
86.4%
91.2%
91.8%
93.6%
93.6%
95.4%
95.8%
97.2%
97.7%
98.3%
N/A
11
18
24
31
38
51
65
79
107
135
N/A
79.2%
86.4%
86.4%
89.3%
91.2%
91.8%
93.6%
94.8%
96.3%
97.2%
Channel Bandwidth [MHz]
Channel Edge
Transmission
Bandwidth [RB]
Resource Block
Channel Edge
Transmission Bandwidth Configuration NRB [RB]
f
Active Resource
Blocks
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Guardband, can be asymmetric
Page 22
Numerology and Frame Structure
f
Configurable
TTI
eMBB
Configurable
subcarrier spacing
mMTC
URLLC
CP length 4.7 µs @ 15 kHz
MBSFN
t
• Scalable multiple numerologies
• Multiple numerologies are supported with 15 kHz * 2^µ (15 kHz to
240 kHz) subcarrier spacing
• Extended CP for 60 kHz
• The CP length scales with the subcarrier spacing
• Predefined numerology set per frequency band
Frequency range
Below 1 GHz
1~6 GHz
Above 6 GHz
SCS options (Non-SS)
15, 30 kHz
15, 30, 60 kHz
60, 120 kHz
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Frequency bands
•
•
<6 GHz, up to 100 MHz per carrier (30 bands defined)
>6 GHz, up to 400 MHz per carrier (4 bands defined)
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Frequency bands
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Numerology and Frame Structure - Slot type



Radio frame 10 ms; Subframe 1 ms; Slot 14/12 OFDM symbols
Types of slots
DL
UL

DL-only slot
Type1: All DL
Type2: All UL

UL-only slot

Mixed DL and UL slot (DL-centric and UL-centric slot)
Uplink Control and/or SRS
Downlink Control
DL
UL
DL-centric
UL-centric
Type3: Mixed DL and UL
The UE can be configured to monitor the PDCCH in any symbol of the slot

Non-slot based scheduling (mini-slot; at least two OFDM symbols)
Dynamic D/U allocation

The slot format can be signaled to the UE via the PDCCH

Semi-static UL/DL configuration and dynamic TDD

Slot aggregation: a transport block can be repeated to improve coverage

Flexible timing between control channel – data channel and data channel –
D
HARQ feedback
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Bandwidth part
BWP1 BW
#1
#2
BWP
BWP BW
BWP2 BW
UE bandwidth capability
Carrier BW
Carrier BW
#3
BWP2
(numerology1)
BWP2
(numerology2)
BWP1 BW
BWP2 BW
Carrier BW

NR carrier bandwidths



5 – 100 MHz for bands 450 MHz – 6 GHz
50 – 400 MHz for bands 24.25 – 52.6 GHz
Bandwidth part (BWP) scenarios



#1: Reduced UE BW capability
#2: UE power saving.
#3: FDM of different numerologies
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Bandwidth part


One BWP is associated with one numerology
Configuration of a BWP includes




Self-contained transmission within BWP





Numerology (sub-carrier spacing, CP type)
Bandwidth (a group of contiguous Resource Blocks)
Frequency location (starting position)
All channels are confined within a active BWP. e.g. PDSCH/PUSCH, PDCCH/PUCCH,
PRACH and etc.
All signals are confined within an active BWP except CSI-RS for RRM. E.g. SS, DMRS, CSIRS for CSI, SRS and etc.
Resource allocation is within a BWP
Up to 4 configured BWPs/BWP pairs, only one active BWP in Rel-15
Flexible gNB and UE bandwidth

UE does not know the gNB bandwidth, it only needs know the BWPs for the UE
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Carrier Aggregation and Dual Connectivity
Scenario 2
F1
F2
Scenario 1
Scenario 3
Scenario 4
• Carrier Aggregation (CA)
• The UE has one RRC connection to the network and there is one MAC entity and one scheduler
• Dual connectivity (DC)
• Radio resources located in two different NG-RAN nodes connected via a non-ideal backhaul and providing either
E-UTRA or NR access and there are two MAC entities and two schedulers
• Synchronized (~35 µs timing difference) and asynchronous (~500 µs) DC is supported for LTE-NR and NR-NR
DC
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Grant Free Access and Data preemption for URLLC
• Service multiplexing
› From network perspective,
multiplexing of transmissions
with different latency and/or
reliability requirements for
eMBB/URLLC in DL is supported
by
freq
URLLC
eMBB
time
Same numerology
freq
» Using the same sub-carrier spacing,
or
» Using different sub-carrier spacing
URLLC
eMBB
time
Different numerology
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Grant Free Access and Data preemption for URLLC
Data preemption for DL multiplexing of URLLC and eMBB
• URLLC transmission may occur in resources scheduled for ongoing eMBB traffic
• To achieve low latency, URLLC PDSCH can preempt the allocated resources for PDSCH of
eMBB.
• gNB indicates eMBB what resources are preempted by URLLC by preemption indication
(PI).
• eMBB can flush the polluted data in the buffer when performing HARQ combining per PI.
Grant free access
• Large delay with grant:
• Scheduling Request  UL grant  UL transmission
• URLLC uplink can be transmitted without gNB grant
Frequency
• Around 50% lower BLER can be achieved after applying PI
URLLC
eMBB
Time
URLLC preempted eMBB PDSCH
• The UE can transmit K repetitions including initial transmission (with the same or
different RV) for the same transport block
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π/2
BPSK
Modulation
π/2
•
•
OFDM: QPSK to 256 QAM
DFT-s-OFDM: π/2 BPSK to 256 QAM
› For DFT-s-OFDM, support π/2 BPSK with FDSS (Frequency Domain Spectrum Shaping)
» Supports max output power for 26 dBm High Power UE
» FDSS filter is up to UE implementation (i.e., TX FDSS filter is transparent to RX)
DMRS
Tx
Multiplexing
0.5*pi-BPSK
modulation
FDSS
SC mapping
IFFT
Equalization
IDFT
0.5*pi-BPSK
demodulation
DFT
Rx
FFT
SC
demapping
Channel
estimation
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Channel coding
•
•
•
Usage of channel coding schemes for the Transport Channels (1%-10% target BLER for data)
•
UL-SCH, DL-SCH, PCH: LDPC codes
•
BCH: Polar codes
Usage of channel coding scheme for control information (0.01%-1% target BLER for control)
•
Downlink Control Information: Polar codes
•
Uplink Control Information: Block codes (Repetition, Simplex, Reed-Muller) and Polar codes
Objectives
Transport Block
•
Peak throughput of 20 Gbps DL and 10 Gbps UL
•
Better performance for control channels
•
IR-HARQ
•
CBG-level retransmissions
•
Code Block
CRC
CRC is appended per Transport Block and per Code Block
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Code Block
CRC
CRC
Code Block
CRC
Rate matching
• Matches the #coded bits to the time-frequency resource and
modulation level
› Puncturing, shortening, repetition
• Circular buffer
› RV0 and RV3 self-decodable
Systematic bits
RV0
RV1
Parity bits
RV2
Systematic bits
Parity bits
RV3
• Limited-buffer rate matching: # soft bits up to largest TBS at rate 2/3
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LDPC channel code
• Invented in 1963 (Gallagher), re-discovered in 1990s
• Benefits over Turbo codes
› Higher throughput efficiency (Gbps/mm2)
› Higher peak throughput
› Higher paralellization in the decoder
» Less decoding complexity
» Smaller decoding latency
› Better performance for high code rates
» Error floor is at lower BLER
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LDPC channel code - encoding
•
Basic LDPC principle: The codewords d fulfil H·d=0
•
•
The LDPC Parity Check Matrix H is generated from a base graph matrix HBG by a lifting process
•
•
Constant row and column weights, no rows have more than one 1 in common. Few 1’s in H.
H is obtained by replacing each element of HBG with a ZxZ matrix, according to the following:
Each element of value 0 in HBG is replaced by an all zero matrix 0 of size ZxZ
Each element of value 1 in HBG is replaced by a circular permutation matrix I(Pi,j) of size ZxZ
NR defines two base graph matrices
•
HBG1 , 46x68 matrix. The corresponding code rate is (68-46)/(68-2)=1/3
•
HBG2 , 42x52 matrix. The corresponding code rate is (52-42)/(52-2)=1/5
•
Usage of base graph depends on code rate and payload
•
This construction is known as Quasi-Cyclic (QC) LDPC codes
•
code rate
Decoding complexity linear in #code bits
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information
length
Page 36
Polar code
•
Invented by Arikan in 2009
•
Asymptotically (for code length N going to infinity) achieves the capacity of any binary input symmetric
memoryless channel with encoding and decoding complexity of the order O(N log N)
•
Applies a linear polarization transform to the encoder input u
•
•
n
d=uGN where G N  G 2  is the n-th Kronecker power of matrix
1 0
G2  

1 1
Above transform together with a successive cancellation decoder structure turns the N available channels (N
channel uses) in to another set of N bit-channels, referred to as synthesised channels, such that the capacities
of these bit channels tend to 0 (fully unreliable) or to 1 (fully reliable) when N goes to infinity.
•
The proportion of reliable channels, K, tends to the capacity of the original communication channel.
•
Data is communicated by placing information bits on the K reliable channels and placing fixed bits (i.e., frozen
bits), usually zeros, on the N-K unreliable channels.
•
Frozen bits and the frozen set known by both the encoder and the decoder. For code length N, information
word length K, code rate R=K/N is constructed.
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Polar code
•
Example with N=8
I(Wi)
Rank
0.0039
8
frozen
0
0.1211
7
frozen
0
0.1914
6
frozen
0
0.6836
5
Data
U4
0.3164
4
frozen
0
0.8086
3
Data
U6
0.8789
2
Data
U7
0.9961
1
Data
U8
0
0
0
0
1
1
1
1
1
1
1
0
Y1
W
Y2
W
Y3
W
1
1
0
1
0
0
1
1
0
0
0
1
1
1
0
Y4
W
Y5
W
Y6
W
Y7
W
1
Input bit index
0
1
1
Y8
1
W
Polarization weight index
{1 2 3 4 5 6 7 8}  {1 2 3 5 4 6 7 8}
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Performance of Polar code
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Reference signals – antenna ports – TX antennas
• Reference signals are transmitted on antenna ports
AP1
W1,1
TX1
W1,2
TX2
W1,3
TX3
W1,4
AP2
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TX4
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Reference signals
• DL/UL Demodulation Reference Signal (DMRS)
› Transmitted in the resources where the channel is
› Precoded in the same way as the data
» Precoding is transparent to the receiver, no need to signal precoder
› Configurable time-freqeuncy density
• DL Channel State Information Reference Signal (CSI-RS)
› Up to 32 antenna ports
› Zero-Power CSI-RS for interference measurement
• DL Tracking Reference Signal (TRS) (new)
› For correcting the frequency error drift, based on CSI-RS
• DL/UL Phase-Tracking Reference Signal (PT-RS) (new)
› For correcting the phase noise at HF bands, dense in time sparse in frequency
• UL Sounding Reference Signal (SRS)
› For channel sounding obtaining CSI
› Useful also for downlink beamforming under channel reciprocity (TDD)
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MIMO
•
Downlink
›
Channel State Information (CSI) reporting
» Rank Indicator (RI): #spatial layers
» Precoder Matrix Indicator (PMI): best precoder matrix given the RI
– Note: The gNB always decides the precoder
» Channel Quality Indicator (CQI): best MCS given the PMI
›
Type I CSI
» Single-panel and multi-panel antennas
›
•
Type II CSI
» Reports up to 4 beams, higher spatial resolution, applicable to MU-MIMO
Uplink
›
Codebook-based transmission
» gNB measures on SRS and indicates rank and precoder to the UE
» Multi-port SRS: the gNB indicates to which SRS antenna ports the precoder should
be mapped
›
Non-codebook based transmission (new)
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MIMO
• Non-codebook based UL transmission
› Step-1: UE reports the number of SRS resources it can simultaneously transmit;
› Step-2: gNB configures a SRS resource set with up to 4 SRS resources and the SRS resource set shall be
associated with a CSI-RS resource configured by RRC signalling;
› Step-3: UE determines candidate precoders based on the associated CSI-RS with reciprocity assumption;
› Step-4: UE sends the configured/triggered SRS resources with multiple precoders derived by CSI-RS
measurement;
› Step-5: gNB receives the SRS resources and indicates the final precoders and the transmission rank for
PUSCH by SRI field in UL/DL grant DCI.
Candidate precoders
Macro site
Macro site
Macro site
SRS
Selected
Resource 1 for
PUSCH
Resource 3
Resource 2
DL RS
Resource 1
Resource 0
UE 1
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UL grant indicate the
selected port
UE 1
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Analog beamforming
s1
D/A
s2
D/A
y1
s1
D/A
y1
y2
y2
yT
yT
Precoder
sL
D/A
• All subcarriers are beamformed with the same weights (phase shifts)
• Beam sweeping is used to cycle through all beams
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Beam measurements
CSI-RS1
CSI-RS2
CSI-RS2
•
•
Initial access: beam sweep measure on
SS block, DL beam associated with
RACH resource
UL beam adjustment: gNB
measures on SRS
Beam correpondence: ULDL pair same as DL-UL
pair
Beam indication: gNB
signals the used CSI-RS
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DL TX adjustment: fix UL beam, sweep
DL beams, measure on CSI-RS, report
best beam(s)
CSI-RS2
•
DL RX adjustment: fix DL beam, sweep
UL beams, measure on CSI-RS, no
reporting
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Beam recovery
• Narrow beams can be easily blocked
• Quick recovery process is defined (measured on CSI-RS or SS block):
1.
2.
3.
4.
Beam-failure detection by UE
Candidate-beam identification by UE
Recovery request send to gNB by UE by the RACH
gNB responds on the beam indicated by the UE
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3GPP 5G Roadmap for Rel-15 and Rel-16
RAN #79
RAN #78
RAN #80
RAN #81
RAN #82
RAN #83
RAN #84
2018
Q1
Q2
① Rel-15
NSA freeze
RAN #86
Q4
Q3
Q1
③ Rel-15
late drop freeze
freeze
Rel-15
NSA RAN4
Q2
Rel-15
ASN.1
Rel-15
corrections
Q3
Late drop
ASN.1
Rel-15 SA RAN4
core spec
RAN #87
2020
2019
② Rel-15
Rel-15
NSA ASN.1
RAN #85
Q1
Q4
WRC-19
Rel-15 RAN4
Performance spec
UE conformance
tests spec
Rel-16 SI/WI phase
Opt.3 EN-DC (NSA)
Opt.3: EPC-LTE&NR NSA
(non-standalone)
EPC
LTE
NR
Opt. 2 & 5
Option 7 & 4
& Sync NR DC
Opt.2: 5GC-NR SA
(standalone)
5G Core
Opt.7: 5GC-LTE&NR
NSA
5G Core
NR
Opt.5: 5GC-LTE SA
5G Core
LTE evolution
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LTE
evo.
NR
Opt.4: 5GC-NR&LTE
NSA
5G Core
LTE
evo.
NR
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Rel-16
RAN1 freeze
Rel-16
freeze
5G spec submission to ITU
no later than February 2020
R15 early drop:
• Option 3 family (3/3a/3x): LTE-NR dual connectivity
with LTE as anchor connected to EPC
R15 “normal” drop:
• Option 2: standalone NR with 5G core network
• Option 5: LTE connected to the 5G core network
R15 late drop:
• Options 7&4: LTE-NR dual connectivity with anchor
connected to the 5G core network
• NR-NR dual connectivity between FR1 and FR2
(synchronized case only)
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Thank you!
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