ICTC 2015 Evolution of LTE-Advanced in 3GPP Rel …griny.kr/ictcsymposium/2015/assets/is1-2.pdfICTC...
Transcript of ICTC 2015 Evolution of LTE-Advanced in 3GPP Rel …griny.kr/ictcsymposium/2015/assets/is1-2.pdfICTC...
Juho Lee
Samsung Electronics
ICTC 2015
Evolution of LTE-Advanced in
3GPP Rel-13/14: a Path to 5G
2
Presentation Outline
• LTE/LTE-Advanced evolution: an overview
• LTE-Advanced in Rel-13
• Expectation for LTE-Advanced in Rel-14
• 3GPP plan for 5G
3
LTE/LTE-Advanced Evolution: An Overview
4
3rd Generation Partnership (3GPP) Project
• Initiated in December 1998 for development of wireless communication standards
• Collaboration between groups of telecommunications associations
– China: CCSA (China Communications Standards Association)
– Europe: ETSI (European Telecommunications Standards Institute)
– Japan: ARIB (Association of Radio Industries and Businesses), TTC (Telecommunication Technology Committee)
– Korea: TTA (Telecommunications Technology Association)
– USA: ATIS (Alliance for Telecommunications Industry Solutions)
– India: TSDSI (Telecommunications Standards Development Society of India)
• Specification work done in Technical Specification Groups
– GERAN (GSM/EDGE Radio Access Network): GERAN specifies GSM radio technology, including GPRS and EDGE
– RAN (Radio Access Network): RAN specifies UTRAN and E-UTRAN
– SA (Service and System Aspects): SA specifies service requirements and overall architecture of 3GPP system
– CT (Core Network and Terminals): CT specifies the core network and terminal parts of 3GPP
W-CDMA (1999)
HSDPA (2002)
HSUPA (2005)
LTE (2008) LTE-A (2010)
B4G (2014) B4G (2016)
DL: 16QAM
AMC, HARQ
UL: AMC, HARQ DL: OFDMA, MIMO
UL: SC-FDMA
CoMP, CA, eICIC
UL MIMO
backward compatible backward compatible
Rel-99 Rel-5 Rel-6 Rel-8/Rel-9 Rel-10/Rel-11
Small cells,
TDD-FDD
CA
Rel-12
FD-MIMO,
LAA, eMTC,
eCA
Rel-13
?
5
LTE/LTE-Advanced Roadmap
2014 2015 2016 2017 2018 2019
1H 2H 1H 2H 1H 2H 1H 2H 1H 2H 1H 2H
Rel-12
Rel-13
Rel-14
Rel-15
2014.12 2015.3
Stage 3 ASN.1 Start of deployment
Stage 3
2015.12
Start of deployment
Stage 3
2017.3
Start of deployment
Stage 3
2018.6
LTE Rel-8: First release of LTE specification (developed in 2008)
LTE-A Rel-10/Rel-11: LTE with 4G capabilities (developed in 2010/2012)
LTE-A Rel-12/Rel-13: LTE with Beyond 4G capabilities
2016.3
ASN.1
2017.6
ASN.1
2018.9
ASN.1
6
LTE/LTE-Advanced Evolution: Targets
• Enhancement: Larger bandwidth, more flexibility, new type of frequency resource
• Effect: Higher peak data rate (300Mbps 4Gbps 25.6Gbps)
Efficient Frequency Usage
• Enhancement: MIMO, higher order modulation, interference control/suppression
• Effect: Higher spectral efficiency (2.0bps/Hz 2.5bps/Hz 4+bps/Hz)
Higher Spectral Efficiency
• Enhancements: Broadcast, device-to-device, public safety, new terminal types
• Effect: Extension of LTE/LTE-A technologies into new applications
Support of New Services
7
LTE/LTE-Advanced Evolution: Technologies
• (Rel-10) CA, (Rel-11) Enhanced CA, (Rel-12) TDD-FDD CA, Dual Connectivity
• (Rel-13) Licensed Assisted Access, Carrier Aggregation Beyond 5 Carriers
Efficient Frequency Usage
• (Rel-10) DL/UL MIMO Enh, eICIC, (Rel-11) CoMP, (Rel-12) Small Cell Enh, NAICS
• (Rel-13) Full Dimension MIMO
Higher Spectral Efficiency
• (Rel-8/9) eMBMS, (Rel-12) D2D, MTC
• (Rel-13) Enh MTC, PS-LTE
Support of New Services
8
LTE-Advanced Rel-13:
Full Dimension MIMO
9
Concept of Full Dimension MIMO (1/2)
3 dimensional beamforming operation with 2D antenna array
Dynamic and flexible vertical or horizontal or 3D sectorization
3D UE-specific beamforming with high-order multiuser MIMO
Vertical sectors
Hotspot
Flexible V/H sectorization 3D beamforming
10
Concept of Full Dimension MIMO (2/2)
Full Dimension MIMO system: 2D array structure with AAS (Active antenna system)
2D patch antenna array with PA integration
Flexible port to antenna array mapping (UE specific and/or cell-specific)
Enable 3D (vertical and horizontal) beamforming
Patch antenna
Feed network
8TX
(8Hx1V)
32TX
(8Hx4V)
FD-MIMO baseband
CPRIs
IP
LTE
infrastructure
FD-MIMO system
Baseband+PA
Passive antennas
Legacy system Flexible system
Flexible 2D port
mapping
11
Beamforming with FD-MIMO
• Example 1: 70/70 degrees without down tilt
2×8 antennas 4×8 antennas 8×8 antennas
2×8 antennas 4×8 antennas 8×8 antennas
• Example 2: 70/70 degrees with down tilt
12
Preliminary Performance Evaluation (1/2)
Evaluation of FD-MIMO with system level simulation
Based on new channel model: 3D UMa, 3D UMi
Number of antenna ports: 8, 16, 32, 64 ports
Overhead assumption: no overhead
Scheduling algorithm Evaluation scenario
Simple PF scheduling is applied
• Step1: Select best UE with SU-CSI
• Step2: Add UE if sum of PF metric is increased
with considering MU interference
• Step3: Recalculate CQI for MU scheduling
Parameter Value
Layout 19 cells with 3 sector
Scenario 3D UMa (ISD:500m), 3D UMi (ISD:200m)
TX power 46dBm(3D UMa), 41dBm (3D UMi)
Carrier frequency 2GHz
Bandwidth 10MHz
Number of UEs 10 UEs per cell
HARQ scheme IR asynchronous retransmission
Link adaptation LTE MCS selection with 10% BLER
CSI feedback Ideal subband Rel.10 SU-CSI
Channel estimation Ideal estimation without error
Element configuration 60º for both vertical and horizontal with
6.5dBi
UE mobility 3Km/h with 3D dropping
13
Preliminary Performance Evaluation (2/2)
System performance of MU-MIMO
By increasing number of antennas in V or H domain:
Narrower beam provides significant MU gain (1x8)(1x64): x2.2 in avg, x4 in edge
With 2D array structure:
Can achieve significant gain with 3D beamforming (1x8)(8x8): x1.76 in avg, x3.3 in edge
Cell vs 5% edge throughput Cell throughput
64 ports
32 ports
16 ports
8 ports
1x64
2x32
4x16
8x8
1x32 2x16
4x8 8x4
4x4
14
LTE-Advanced Rel-13:
Licensed Assisted Access
15
Licensed vs Unlicensed Band
Licensed Band
Unlicensed Band
• License typically requires a fee (a big one)
Operator retains exclusive rights for use
• High transmission power (ex. 46dBm)
Suitable for providing large coverage
• Communication based on resource
allocation, link adaptation, HARQ
QoS can be guaranteed
• A frequency resource is used by single
radio access technology (ex. LTE, WCDMA)
• No license and therefore no fee (free)
Anyone can use
• Low transmission power (ex. 23dBm)
Coverage is limited
• Communication based on collision
avoidance
QoS cannot be guaranteed
• A frequency resource is used by multiple
radio access technologies (ex. Bluetooth, WiFi)
Licensed band and unlicensed band have different characteristics
LAA aims to provide licensed wireless experience in unlicensed band
16
• Conventional LTE/LTE-A: Data and control signaling on licensed carrier
• WiFi: Data and control signaling on unlicensed carrier
• LAA: Data on licensed and unlicensed carrier but control on licensed carrier only
Licensed Assisted Access (LAA) Concept
Licensed f
Licensed f
Unlicensed f
Unlicensed f
UnLicensed f
Licensed f
Licensed Assisted
Mobility support, reliable data/control pipe
Data fat pipe
17
Benefits of LAA
Enhanced User Experience Unified LTE Network
Cellular mechanism over unlicensed band
(coverage, mobility, QoS control) Same core elements
Improved spectral efficiency vs WiFi
(link adaptation, HARQ, interference management) Same mobility and security framework
Source: Huawei
18
LAA Deployment Scenarios
19
LAA Performance (Indoor)
• System level evaluation for 3 setups
– WiFi performance in an area with two WiFi operators
– WiFi performance in an area with one WiFi operator and one LAA operator
– LAA performance in an area with one WiFi operator and one LAA operator
• Observations
– A: WiFi performance has improved LAA is a better neighbor to WiFi
– B: LAA performance is higher than WiFi LAA is more efficient than WiFi
Average User Perceived Throughput 5% Cell Edge UE Throughput
0
20
40
60
80
100
120
WiFi in WiFi only WiFi in WiFi+LAA LAA in WiFi+LAA
Mbps
Low load
Medium load
High load
A
B
0
10
20
30
40
50
60
70
80
WiFi in WiFi only WiFi in WiFi+LAA LAA in WiFi+LAA
Mbps
Low load
Medium load
High load
A
B
20
LTE-Advanced Rel-13:
Carrier Aggregation Beyond 5 Carriers
21
CA Beyond 5 Carriers
• Carrier aggregation history
– Rel-10: Introduction of CA (up to 5 carriers, 100MHz)
– Rel-11: TDD CA enhancement (flexible UL/DL ratios)
– Rel-12: TDD-FDD CA, dual connectivity (inter-eNB CA)
– Rel-13: CA with 32 CCs
• Carrier aggregation (CA) is the most successful LTE-A feature
– Every year, CA capability in terminals are enhanced 4CC CA coming soon
• In order to fully utilize unlicensed band, next generation CA is necessary
– Up to 32 component carriers: up to 640MHz and 25.6Gbps
22
Key Specification Support
Carrier Aggregation of up to 32 CCs
• With the availability of unlicensed spectrum on 5.8GHz, significantly larger spectrum can be used for carrier aggregation
- Current CA specification supports up to 5 CCs and 100MHz
Category 8, 4Gbps
- Next generation CA specification will support up to 32 CCs
Combined bandwidth of up to 640MHz
At least on paper, data rate of 25.6Gbps
• Like all CA enhancements so far, collocated (or with ideal backhaul) scenario is assumed
• Key area of specification support is to enhance how uplink and downlink control information is conveyed
PUCCH on SCell
• Rel-12: PUCCH on SCell was introduced to support dual connectivity eNBs with non-ideal backhaul
- Due to non-ideal backhaul, L1 signaling cannot be
exchanged in real time
• Rel-13: PUCCH on SCell will be introduced to support inter-site eNB CA more efficiently
- Offloading of uplink L1 signalling
PUCCH PUCCH
PCell
SCell Ideal backhaul
Licensed band Unlicensed band
…1 2 3 4 5 6 32
23
LTE-Advanced Rel-13:
Enhanced Machine Type Communications Narrow Band Internet of Things (NB-IoT)
24
Further LTE PHY Layer Enhancements for MTC
• Key objectives
– UE Cost reduction (e.g. 1.4MHz narrowband operation)
– Coverage enhancement (15 dB improvement)
– UE Power Consumption reduction
• Expected benefits
– New revenue generation for operators by means of boosting coverage of LTE based MTC UE
– Enable new cellular IoT device targeted services
System bandwidth
MTC UE bandwidth (1.4MHz)
Coverage improvement (+15dB)
Reduced MTC UE power consumption
25
Rel-13 Enhanced MTC vs Rel-12 MTC
• Feature comparison
Feature Cat-4 Cat-1 Rel-12 MTC Rel-13 eMTC
UE RF Bandwidth 20 MHz 20 MHz 20 MHz 1.4 MHz
DL Peak Rate 150 Mbps 10 Mbps 1 Mbps ~200 kbps
Max No of DL Layers 2 1 1 1
UL Peak Rate 50 Mbps 5 Mbps 1 Mbps ~200 kbps
No of RF Rx chains 2 2 1 1
Max UE Tx power 23 dBm 23 dBm 23 dBm ~20 dBm
Duplex Mode Full Full Half (optional) Half (optional)
Relative BOM Cost 125% 100% 50% 20-25%
Rel-12 MTC Rel-13 MTC Description
RF bandwidth 20 MHz 1.4 MHz Impact on control channels(PHICH, PCFICH, (E)PDCCH) and data channel scheduling
Reduced BW operation
Control: System BW Data: Reduced BW
Control : Reduced BW Data : Reduced RB
EPDCCH or new channel format for control channels
Coverage enhancement
No Yes Physical channel repetition, etc. required
Max. Tx Power 23 dBm ~20 dBm
Max. TBS size 1000 bits(unicast) 2216 bits(broadcast)
1000 bits (unicast and broadcast)
• Cost comparison (RP-141180)
26
Narrow Band Internet of Things (NB-IoT)
• Need for efficient support of low throughput (up to ~40 kbps) and low complexity Machine Type
Communications with a very narrow bandwidth
– E.g., should be possible to reuse a GSM carrier(s) of 200kHz
• Targets
– Improved indoor coverage: 20 dB extension compared to legacy GPRS, i.e., target MCL = 164 dB
– Support for massive number of low throughput devices: ~ 50,000 devices / macro cell site
– Ultra low cost
– Improved power efficiency: up to 10-year battery life of 5Wh (e.g., AA battery)
– Relaxed delay sensitivity: 10 seconds for uplink event-triggered reporting
• Current status and standardization plan for inclusion in Rel-13 – GERAN conducted a feasibility study on CIoT from May 2014 to August 2015 (TR 45.820)
– RAN started a work item NB-IoT in Sep 2015 with targeting completion in March 2016
• 180 kHz UE RF bandwidth for both downlink and uplink
• Supported scenarios: stand-alone, LTE in-band, LTE guard band
• Strive for a single solution among proposed technologies
– Downlink: OFDMA w/ 15 kHz subcarrier spacing vs 3.75 kHz subcarrier spacing
– Uplink: SC-FDMA w/ 2.5 kHz subcarrier spacing vs
GMSK FDMA w/ 5 kHz subcarrier spacing (3.75k symbols/s) and channel bonding
27
Expectation for LTE-Advanced in Rel-14
28
FD-MIMO Enhancement
• Completion of Rel-13 FD-MIMO work item will enable specification support for
– Non-precoded CSI-RS for 16 ports that is mapped to TXRUs in 2D (ex: 4 x 4, 2 x 8, 8 x 2)
– Beamformed CSI-RS
– CSI taking into account the 2D array structure (codebook, periodic/aperiodic reports)
– Enhanced SRS and DMRS
• Rel-14 eFD-MIMO will build upon the above features to provide
– Support for 32 antenna ports and more with (potentially) more flexible antenna array configuration
– Improved performance, extended applicability (use cases)
29
LAA Enhancement
• Potential areas of enhancement include LAA UL support (if precluded from Rel-13) and other
left-over items from Rel-13
– Framework for uplink LBT to be defined in Rel-13
30
Latency Reduction
• Latency reduction is always important to maximize user experience
• A study item has already started aiming to provide specification support in Rel-14
• Important to keep backward compatibility to support Rel-14 as well as legacy UEs
31
V2X
• Motivation
– V2X services require low latency and high reliability
– Market opportunity for enhanced D2D to be used for V2V applications
• Aspects for consideration
– Communications: massive-scale resource allocation with low overhead
– Network: real-time data collection, computing and routing
– Sensing: enhanced positioning accuracy
– Inter-PLMN support, spectrum for V2V (dedicated spectrum or shared spectrum)
32
3GPP Plan for 5G
33
5G timeline in 3GPP (SP-150149)
IMT-2020 specifications
Evaluation
5D#23Feb 16
5D#26Feb 17
5D#27Jun 17
Requirements
Evaluation criteria
Initial submissions of proposals
5D#28Oct 17
5D#32Jun 19
5D#31Oct 18
5D#34Feb 20
5D#36Oct 20
RAN#70Dec 15
channel modeling
RAN#69Sep 15
RAN#72Jun 16
RAN#86Jun 20
RAN SI: scope & requirements
HSPA/LTE evolution
IMT
20
20
RAN WG SI: evaluation of solutions RAN WG WI: specification of solutions
Fina
l 3G
PP
subm
issi
on
Init
ial 3
GPP
su
bmis
sion
IMT 2020
requirements
RAN#71 Mar 16
Rel-13 freeze
RAN Workshop
3G
PP
requ
irem
ents
SA system work
RAN-SA Workshop
SA1 SMARTER SI SA1 SMARTER WI
34
5G Usage Scenario
• Support for various usage scenarios such as eMBB, mMTC, and UR/LL
• New RAT(s) to utilize various spectrum bands up to 100 GHz
Enhanced Mobile Broadband
Mobile Cloud Computing
UHD Streaming
Ultra Reliability / Low Latency
Smart Vehicle Industrial Automation
Massive Machine-type Comm.
Smart Home/ Smart City
U-Health/Wearables
35
5G Requirement (to be developed from Dec 2015)
• Example requirement set
36
Details of 3GPP plan for 5G standards
• There will be a new, non-backward compatible, radio for 5G
– LTE evolution will continue in parallel
• Phasing approach
– Phase 1 (Rel-15) to be completed around Sep 2018 to address a more urgent subset of the commercial needs
– Phase 2 (Rel-16) to be completed by Dec 2019 for the IMT2020 submission and to address all identified use cases and requirements
• Detailed work plan in 3GPP RAN
– Study item on channel model for high frequency bands above 6 GHz started in September 2015
– RAN to approve in December 2015 a study item to develop scenarios and requirements for 5G radio technology
– RAN to approve in March 2016 a study item for RAN WGs to evaluate technology solutions for 5G radio technology
37
Thank you