tranining lte

7/30/2019 Tranining LTE

1/133

LTE-Advanced

[email protected]

LG


2/133

LTE-AdvancedLTE-Advanced 2

Contents

Generals on LTE-Advanced Overview of LTE-Advanced Technologies

More details on LTE-Advanced Component

Technologies


3/133

LTE-Advanced : Generals

Definition of LTE-Advanced

Major milestones for LTE-Advanced

Requirements and targets for LTE-Advanced Current status of LTE-Advanced

Self Evaluation Results

Bands identified for IMT-Advanced


4/133

LTE-Advanced

3GPP specification releases

1999 2000 2001 2002 2003 2004 2005

Release 99

Release 4

Release 5

Release 6

1.28Mcps TDD

HSDPA, IMS

W-CDMA

HSUPA, MBMS, IMS+

2006 2007 2008 2009

Release 7 HSPA+ (MIMO, HOM etc.)

Release 8

2010 2011

LTE, SAE

ITU-R M.1457

IMT-2000 Recommendations

Release 9

LTE-AdvancedRelease 10

GSM/GPRS/EDGE enhancements

Small LTE/SAE

enhancements

Cited from 3GPP, RP-091005, Proposal for Candidate Radio Interface Technologies for IMT-Advanced Based on LTE Release 10 and Beyond


5/133

LTE-Advanced 5

Definitions

What is IMT-Advanced? A family of radio access technologies fulfilling IMT-Advanced

requirements

Relates to 4G as IMT-2000 relates to 3G

IMT spectrum will be available to both IMT-2000 and IMT-Advanced

What is LTE-Advanced? System now under study in 3GPP aiming toward IMT-Advanced within

WP5D time line

Formal name: Advanced E-UTRA /Advanced E-UTRAN Evolution from 3GPP LTE specifications, not a revolution

Comparable potential of 3GPP LTE with target requirements of IMT-advanced Fast and efficient correspondence against the timeline of WP5Ds specification

and commercialization for IMT-advanced Cost-efficient support for backward and forward compatibility between LTE and

LTE-A Natural evolut ion of LTE (LTE release 10 & beyond)


6/133

LTE-Advanced

Detailed Timeline for ITU-R

3/08 6/08 12/08 3/09 5/09 9/09 12/09 3/109/08

LTE-AdvancedSI Approved

3GPP LTE-Advanced

EarlySubmission to

ITU-R

Steps 1 & 2

Circular Letter & Development of Candidate RITs3/08 to 10/09

IMT-AdvancedEvaluationGroup(s)Formed

(notify ITU-R)

3GPP

Initiate3GPP LTE-Advanced

Self-Evaluation

3GPP LTE-Advanced FinalSubmission toITU-R including

Updated

TechnicalSubmission &Required Self-

Evaluation

LTE-Advanced

Specifications

3GPP LTE-AdvancedCompleteTechnical

Submission toITU-R

Step 3

Submission

3/09 to 10/09

Step 4

Evaluations

1/09 to 6/10

3/08 6/08

10/09

10/09

6/103/09

ITU-R

Detailed Timelines for ITU-R Steps 1- 4

3/09

LTE-AdvancedSpecifications

to ITU-R~J an 2011

Evaluation ofITU-R

Submissions

EvalReports

ITU-R CircularLetter 5/LCCE/2

Process &Timelines

ITU-R CircularLetter Addendum

5/LCCE/2 +Requirements& SubmissionTemplates

Cutoff forEvaluation Reports

to ITU-RJ une 2010

INDUSTRY

RAN #41 RAN #42 RAN #43RAN #39 RAN #44RAN #40 RAN #45

WP 5D #1 WP 5D #2

WP 5D #4

WP 5D #8

WP 5D #6

WP 5D #4 WP 5D #6

RAN #47RAN #46

[~Release 10 ]

[~RAN #50 12/10]

6/09WP 5D #5

10/08WP 5D #3

5 Source: RP-080651

ITU-REvaluation

Criteria

3GPP work on ITU-R Step 2Technology Development

3GPP work on ITU-R Step 3Technology Submission

3GPP Q&A withevaluation

groups(as required)


7/133

LTE-Advanced

IMT-Advanced Process

Steps in radio interface development process:

Step1 and 2

No.1 No.2 No.3 No.4 No.5 No.6 No.7 No.8 No.9

Step 3

(0)

(1)

(20 months)

Step 4

(8 months)

(16 months) (2)

Steps 5,6 and 7

(3)Steps 8

(4)(12 months)

(20 months)

WP 5D

meetings

Step 1: Issuance of the circular letter

Step 2: Development of candidate RITs and SRITs

Step 3: Submission/Reception of the RIT and SRIT proposals

and acknowledgement of receipt

Step 4: Evaluation of candidate RITs and SRITs

by evaluation groups

Step 5: Review and coordination of outside evaluation activities

Step 6: Review to assess compliance with minimum requirements

Step 7: Consideration of evaluation results, consensus building

and decision

Step 8: Development of radio interface Recommendation(s)

Critical milestones in radio interface development process:

(0): Issue an invitation to propose RITs March 2008

(1): ITU proposed cut off for submission October 2009

of candidate RIT and SRIT proposals

(2): Cut off for evaluation report to ITU June 2010

(3): WP 5D decides framework and key October 2010

characteristics of IMT-Advanced RITs and SRITs

(4): WP 5D completes development of radio February 2011

interface specification Recommendations

2008 2009 2010No.10

2011

IMT-Advanced A2-01


8/133

LTE-Advanced

Major Milestones for LTE-Advanced

Major milestones for LTE-Advanced in 3GPP

1st workshop in November 2007 Cancun Approval of LTE-Advanced study item: Rapporteur: NTT DoCoMo 2nd workshop in April 2008 Shenzhen 3rd workshop in May 2008 Prague Approval of LTE-A requirement TR: TR 36.913 v8.0.0 approved in RAN#40 in May Early proposal to ITU-R WP5D in October 2008 Complete submission to ITU-R in J une 2009 (WP5D #5) Approval for RAN TR (TR 36.912) for ITU-R submission in September, 2009 Final proposal update to ITU-R in October 2009 (WP5D #6) Study item completion in March 2010

LTE-Advanced function block work items started in December, 2009, irrespective of completion for LTE-Advanced study item

Initial approval of LTE-A (Rel-10 specification) will be done in December, 2010 Functional freezing will be done at the same time in December next year

ASN.1 freezing is expected to be done in March or June 2011

ITU-R WP5D ProposalsEvaluation

Consensus

Specification

LTE Rel.9 LTE Rel.10 [LTE Rel.11]

LTE-A SI

2009 2010 2011Complete Tech

Final Submission

Standard Roadmap

3GPPLTE-A LTE-A Functional Work Items

[LTE Rel.12]

2012

Beyond LTE-A SI


9/133

LTE-Advanced

Agreed upon Time Plan for Rel-10

12.09 3.10 6.10 9.10 12.10 3.11 6.11

#46 #47 #48 #49 #50 #51 #52

Expected

Functional

freeze

In RAN1

RAN1 has to complete theirspecification by Sept. 10(only 9 month)

RAN2/3/4 have to completetheir specification by Dec.10 (only 12 month) reflectingRAN1 agreements

Core specFunctional

freeze

ASN.1freeze


10/133

LTE-Advanced

Documents Related to LTE-Advanced

TR (Technical Report)TR 36.806

Technical report for relay architecture

TR 36.814 (RAN1 technical report)

Evolved Universal Terrestrial Radio Access (E-UTRA); Further

advancements for E-UTRA Physical layer aspectsTR 36.815

LTE-Advanced feasibility studies in RAN WG4

TR 36.912 (RAN technical report)

Feasibility study for Further Advancements for E-UTRA (LTE-

Advanced)

TR 36.913

Requirements for further advancements for Evolved UniversalTerrestrial Radio Access (E-UTRA)


11/133

LTE-Advanced

RAN TR for LTE-Advanced

TR 36.912: RAN plenary TR for LTE-Advanced study item RP-090743: TR36.912 v9.0.0 Approved in RAN #45 Will be submitted to ITU-R after PCG approval

Contents1. Scope2. References3. Definitions, symbols and abbreviations4. Introduction

5. Support of wider bandwidth6. Uplink transmission scheme7. Downlink transmission scheme8. CoMP9. Relaying10. Improvement for latency11. Radio transmission and reception12. Mobility enhancements13.TS 36.133 requirements enhancements

14. MBMS enhancements15. SON enhancements16. Self-evaluation report on LTE Rel.10 & beyond (LTE-Advanced)Annexs


12/133

LTE-Advanced

Requirements for LTE-Advanced [1]

General requirement LTE-Advanced is an evolution of LTE

LTE-Advanced shall meet or exceed IMT-Advancedrequirements within the ITU-R time plan

Extended LTE-Advanced targets are adopted

System

Performance

IMT-Advancedrequirements and time plan

Rel. 8 LTE

LTE-Advanced

targets

Time

Cited from 3GPP, RP-091005, Proposal for Candidate Radio Interface Technologies for IMT-Advanced Based on LTE Release 10 and Beyond


13/133

LTE-Advanced


Comparison between IMT-Advanced and LTE-Advanced

LTE-Advanced should at least fulfill or exceed IMT-Advanced requirements

ITU Requirement 3GPP Requirement

Peak data rates1Gbps in DL

500Mbps in UL

Bandwidth 40MHz (scalable BW) Up to 100MHz

User plane latency 10ms Improved compared to LTE

Control plane latency 100msActive Active dormant(


14/133

LTE-Advanced


System performance requirements for IMT-Advanced

ITU system performance requirement

Enviromnet Indoor Micro-cell

Base

coverage

Urban

Rural/

High speed

Spectrum

Efficiency

DL

(4x2 MIMO)3 2.6 2.2 1.1

UL

(2x4 MIMO)2.25 1.8 1.4 0.7

Cell EdgeSpectrum

Efficiency

DL

(4x2 MIMO) 0.1 0.075 0.06 0.04

UL

(2x4 MIMO)0.07 0.05 0.03 0.015


15/133

LTE-Advanced


System Performance Requirements from TR 36.913

Peak Spectral Efficiency: DL 30bits/Hz (8x8 MIMO), UL 15bps/Hz (4x4 MIMO)

Seem to be easily achievable by means of extended utilization of #of antennas

Average Spectral Efficiency (SE) and Edge Spectral Efficiency for LTE Case-1 System performances of LTE Rel-8 are about 30% ~ 70% lower than 3GPP target

What would be key enabling technologies to fil l up the gap between two?

Case-1

Ant. Config

LTE

Cell Avg. SE

[bps/Hz/cell]

(3GPP R1-072580)

LTE-ADV

Cell Avg. SE

[bps/Hz/cell]

(3GPP TR36.913)

LTE

Cell Edge SE

[bps/Hz/user]

(3GPP R1-072580)

LTE-ADV

Cell Edge SE

[bps/Hz/user]

(3GPP TR36.913)

UL1x2 0.735 1.2 0.024 0.04

2x4 - 2.0 - 0.07

DL

2x2 1.69 2.4 0.05 0.07

4x2 1.87 2.6 0.06 0.09

4x4 2.67 3.7 0.08 0.12


16/133

LTE-Advanced

Frequency Bands Identified for LTE-A WRC 07 identified some new IMT spectrum that is now under band planning

There should be either a clear FDD band plan or TDD band plan

3300 3400 3500 3600 3700 3800 3900 4000 4100 4200 4300 4400 4500 4600 4700 4800 4900 5000

1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 2600 2700 2800 2900

2025 21102170

26901710

100 500 600 700 800 900 1000200 300 400

5150 470890915

925960806450 790

698

New for IMT in somecountries of

Regions 1 & 3

New

Region 2

NewGlobal

ExistingIMT

identified

IMT bands can be used by all IMT-2000 and IMT-Advanced technologies


17/133

LTE-Advanced

Current Status of LTE-Advanced

Status related to IMT-Advanced submission Early proposal in October 2008

Main purpose was to inform ITU-R of 3GPPs resolution for IMT-Advanced and provideupdated status of LTE-Advanced to ITU-R

Complete technology submission in J une 2009 Initial proposal submission from 3GPP Compliant with the formal form of submissition requested by ITU-R Separate RIT for FDD and TDD

Performance results were not included in the submission Final submission in October 2009

Final proposal update to ITU-R Self evaluation results for LTE-Advanced were included

Status of LTE-Advanced in 3GPP Study item has been formally completed in last RAN plenary meeting in March Several new work items with respect to LTE-Advanced were created, targetting

Rel10 time frame Carrier aggregation work item: created in December 2009 Enhanced DL MIMO work item: created in December 2009 UL MIMO work item: created in December 2009 Relay work item: created in December 2009 Enhanced ICIC for non-ca based HetNet: created in March 2010


18/133

LTE-Advanced

Self-Evaluation Activities in 3GPP

RAN1 activities with respect to self evaluations for LTE-Advanced List of companies who submitted self evaluation results:

Alcatel-Lucent, CATT, CMCC, Ericsson, Fujitsu, Hitachi, Huawei, LGE,Motorola, NEC, Nokia, NTT DOCOMO, Panasonic, Qualcomm, RITT,Samsung, Texas Instruments, ZTE

How to capture self evaluation results from a lot of companies Since different companies have somewhat different assumptions on the

overhead, the group had to make decision on the common assumption for theoverhead so that the results from different companies can be comparable witheach other

What kinds of features should be prioritized? LTE-Advanced is based on LTE Rel.8 and it is the long term evolution of LTE, thus It is good to inform that LTE Rel.8 can fulfill the most of requirements without any

enhanced techniques. It is also good to inform that only small updates from Rel.8 can fulfill the requirements

even in the very tough conditions (UMi and Uma). Thus, Rel-8 performance is captured if it fulfill s the requirements. If Rel-8 cannot meet the req. , we should pr ior itize ones wi th small extension

from Rel-8, i.e., DL: Rel-8 >MUMIMO >CS/BF-CoMP and J P-CoMP UL: Rel-8 >MUMIMO, SUMIMO and CoMP


19/133

LTE-Advanced

Summary of Self-Evaluation Results

From the self evaluation activities, it was found that

For LTE Release 10, FDD RIT Component meets the minimum requirements of all 4 required test

environments

TDD RIT Component meets the minimum requirements of all 4 required testenvironments

The complete SRIT meets the minimum requi rements of all 4 required testenvironments.

Baseline configuration exceeding ITU-R requirements with minimum extension LTE release 8 fulfills the requirements in most cases (no extensions needed)

Extensions to Multi-user MIMO from Release 8 fulfills the requirements in some scenarios(Urban Macro/Micro DL)

More advanced configurations, e.g. CoMP, with further enhanced performance

Many (18) companies perticipated in the simulations, ensuring high reliability Self evaluation reports are captured in section 16 of Technical Report TR 36.912


20/133

LTE-Advanced

Self-Evaluation Results [1]

Peak spectrum efficiency

DL peak spectrum efficiency

UL peak spectrum efficiency

SchemeFDD spectral efficiency

(bps/Hz)

TDD spectral efficiency

(bps/Hz)

ITU requirement 15 15

Rel-8 4 layer spatial multiplexing 16.3 16.0

8 layer spatial multiplexing 30.6 30.0

SchemeFDD spectral efficiency

(bps/Hz)

TDD spectral efficiency

(bps/Hz)

ITU requirement 6.75 6.75




21/133

LTE-Advanced

Self-Evaluation Results [2] Indoor Hotspot / downlink / FDD

LTE Rel-8 meets the requirement

Indoor Hotspot / downlink / TDD LTE Rel-8 meets the requirement

Scheme and antenna

conf.

ITU

requirement

(Ave./Edge)

Number

of

samples

Cell average Cell edge

L=1 L=2 L=3 L=1 L=2 L=3

Rel-8 SU-MIMO4X2 (A)

3 / 0.1 15 4.8 4.5 4.1 0.23 0.21 0.19

MU-MIMO4X2 (C)

3 / 0.1 3 6.6 6.1 5.5 0.26 0.24 0.22

Scheme and antenna

conf.

ITU

requirement(Ave./Edge)

Number

ofsamples


L=1 L=2 L=3 L=1 L=2 L=3

Rel-8 SU-MIMO4X2 (A)

3 / 0.1 10 4.7 4.4 4.1 0.22 0.20 0.19

MU-MIMO4X2 (C)

3 / 0.1 4 6.5 6.1 5.7 0.23 0.22 0.20


22/133

LTE-Advanced


Indoor Hotspot / upl ink / FDD


Indoor Hotspot / upl ink / TDD


Scheme and antenna conf.ITU requirement

(Ave./Edge)

Number of

samplesCell average Cell edge

Rel-8 SIMO 1X4 (A) 2.5 / 0.07 13 3.3 0.23

Rel-8 SIMO 1X4 (C) 2.5 / 0.07 10 3.3 0.24

Rel-8 MU-MIMO 1X4 (A) 2.5 / 0.07 2 5.8 0.42SU-MIMO 2X4 (A) 2.5 / 0.07 5 4.3 0.25


(Ave./Edge)

Number of

samples


Rel-8 SIMO 1X4 (A) 2.5 / 0.07 9 3.1 0.22

Rel-8 SIMO 1X4 (C) 2.5 / 0.07 7 3.1 0.23

Rel-8 MU-MIMO 1X4 (A) 2.5 / 0.07 2 5.5 0.39

SU-MIMO 2X4 (A) 2.5 / 0.07 2 3.9 0.25


23/133

LTE-Advanced


Urban Micro/downlink/FDD:Single cell MU-MIMO meets the requirement

Urban Micro/downlink/TDD: single cell MU-MIMO (4x2) meets the requirement

Scheme and antenna

conf.

ITUrequirement

(Ave./Edge)

Numberof

samples


L=1 L=2 L=3 L=1 L=2 L=3

MU-MIMO 4X2 (C) 2.6 / 0.075 8 3.5 3.2 2.9 0.11 0.096 0.087

MU-MIMO 4X2 (A) 2.6 / 0.075 3 3.4 3.1 2.8 0.12 0.11 0.099

CS/BF-CoMP 4X2 (C) 2.6 / 0.075 5 3.6 3.3 3.0 0.11 0.10 0.089

J P-CoMP 4X2 (C) 2.6 / 0.075 1 4.5 4.1 3.7 0.14 0.13 0.12

MU-MIMO 8X2 (C/E) 2.6 / 0.075 4 4.2 3.8 3.5 0.15 0.14 0.13

Scheme and antenna

conf.

ITU

requirement

(Ave./Edge)

Number

of

samples


L=1 L=2 L=3 L=1 L=2 L=3

MU-MIMO 4X2 (C) 2.6 / 0.075 8 3.4 3.2 3.0 0.10 0.096 0.089

MU-MIMO 4X2 (A) 2.6 / 0.075 1 3.1 2.9 2.7 0.11 0.10 0.095

CS/BF-CoMP 4X2 (C) 2.6 / 0.075 3 3.5 3.3 3.1 0.099 0.092 0.086

J P-CoMP 4X2 (C) 2.6 / 0.075 1 4.5 4.2 3.9 0.098 0.092 0.085

MU-MIMO 8X2 (C/E) 2.6 / 0.075 4 4.1 3.9 3.6 0.11 0.11 0.10


24/133

LTE-Advanced


Urban Micro / uplink / FDD: LTE Rel-8 meets the requirement

Urban Micro / upl ink / TDD: LTE Rel-8 meets the requirement


(Ave./Edge)

Number of


Rel-8 SIMO 1X4 (C) 1.8 / 0.05 13 1.9 0.072

Rel-8 MU-MIMO 1X4 (A) 1.8 / 0.05 2 2.5 0.077

MU-MIMO 2X4 (A) 1.8 / 0.05 1 2.5 0.086


(Ave./Edge)

Number of


Rel-8 SIMO 1X4 (C) 1.8 / 0.05 9 1.9 0.070

Rel-8 MU-MIMO 1X4 (A) 1.8 / 0.05 2 2.3 0.071

MU-MIMO 2X4 (A) 1.8 / 0.05 1 2.8 0.068

MU-MIMO 1X8 (E) 1.8 / 0.05 1 3.0 0.079


25/133

LTE-Advanced


Urban Macro / downlink / FDD: Single cell MU-MIMO (4x2) meets the requirement

Urban Macro / downlink / TDD: Single cell MU-MIMO (4x2) meets the requirement

Scheme and antenna

conf.

ITU

requirement

(Ave./Edge)

Number

of

samples


L=1 L=2 L=3 L=1 L=2 L=3

MU-MIMO 4X2 (C) 2.2 / 0.06 7 2.8 2.6 2.4 0.079 0.073 0.066

CS/BF-CoMP 4X2 (C) 2.2 / 0.06 6 2.9 2.6 2.4 0.081 0.074 0.067

JP-CoMP 4X2 (A) 2.2 / 0.06 1 3.0 2.7 2.5 0.080 0.073 0.066

CS/BF-CoMP 8X2 (C) 2.2 / 0.06 3 3.8 3.5 3.2 0.10 0.093 0.085

Scheme and antenna conf.

ITU

requirement

(Ave./Edge)

Number

of

samples


L=1 L=2 L=3 L=1 L=2 L=3

MU-MIMO 4X2 (C) 2.2 / 0.06 7 2.8 2.6 2.4 0.076 0.071 0.067

CS/BF-CoMP 4X2 (C) 2.2 / 0.06 4 2.8 2.6 2.4 0.082 0.076 0.071

JP-CoMP 4X2 (C) 2.2 / 0.06 1 3.5 3.3 3.1 0.087 0.082 0.076

CS/BF-CoMP 8X2 (C/E) 2.2 / 0.06 3 3.5 3.3 3.1 0.10 0.093 0.087


26/133

LTE-Advanced


Urban Macro / uplink / FDD LTE Rel-8 meets the requirement

Urban Macro / uplink / TDD



(Ave./Edge)

Number of


Rel-8 SIMO 1X4 (C) 1.4 / 0.03 12 1.5 0.062

CoMP 1X4 (A) 1.4 / 0.03 2 1.7 0.086

CoMP 2X4 (C) 1.4 / 0.03 1 2.1 0.099


(Ave./Edge)

Number of


Rel-8 SIMO 1X4 (C) 1.4 / 0.03 9 1.5 0.062

CoMP 1X4 (C) 1.4 / 0.03 1 1.9 0.090

CoMP 2X4 (C) 1.4 / 0.03 1 2.0 0.097

MU-MIMO 1X8 (E) 1.4 / 0.03 1 2.7 0.076


27/133

LTE-Advanced


Rural Macro / downlink / FDD: LTE Rel-8 meets the requirement

Rural Macro / downlink / TDD: LTE Rel-8 meets the requirement


ITU

requirement

(Ave./Edge)

Number

of

samples


L=1 L=2 L=3 L=1 L=2 L=3

Rel-8 SU-MIMO 4X2 (C) 1.1 / 0.04 15 2.3 2.1 1.9 0.081 0.076 0.069

Rel-8 SU-MIMO 4X2 (A) 1.1 / 0.04 14 2.1 2.0 1.8 0.067 0.063 0.057

MU-MIMO 4X2 (C) 1.1 / 0.04 3 3.9 3.5 3.2 0.11 0.099 0.090

MU-MIMO 8X2 (C) 1.1 / 0.04 1 4.1 3.7 3.4 0.13 0.12 0.11


ITU

requirement

(Ave./Edge)

Number

of

samples


L=1 L=2 L=3 L=1 L=2 L=3

Rel-8 SU-MIMO 4X2 (C) 1.1 / 0.04 8 2.0 1.9 1.8 0.072 0.067 0.063

Rel-8 SU-MIMO 4X2 (A) 1.1 / 0.04 7 1.9 1.7 1.6 0.057 0.053 0.049

MU-MIMO 4X2 (C) 1.1 / 0.04 4 3.4 3.2 3.0 0.095 0.089 0.083

MU-MIMO 8X2 (C/E) 1.1 / 0.04 2 3.9 3.6 3.4 0.11 0.11 0.10

Rel-8 single-layer BF 8X2 (E) 1.1 / 0.04 4 2.4 2.3 2.1 0.11 0.10 0.093


28/133

LTE-Advanced


Rural Macro / uplink / FDD: LTE Rel-8 meets the requirement

Rural Macro / uplink / TDD: LTE Rel-8 meets the requirement


(Ave./Edge)

Number of


Rel-8 SIMO 1X4 (C) 0.7 / 0.015 11 1.8 0.082

Rel-8 MU-MIMO 1X4 (A) 0.7 / 0.015 2 2.2 0.097

CoMP 2X4 (A) 0.7 / 0.015 2 2.3 0.13


(Ave./Edge)

Number of


Rel-8 SIMO 1X4 (C) 0.7 / 0.015 8 1.8 0.080

Rel-8 MU-MIMO 1X4 (A) 0.7 / 0.015 2 2.1 0.093

CoMP 2X4 (A) 0.7 / 0.015 1 2.5 0.15

MU-MIMO 1X8 (E) 0.7 / 0.015 1 2.6 0.10


29/133

LTE-Advanced


VoIP capacity: Rel-8 LTE meets all the requirements

Antenna

conf.Scenarios

ITU

requirement

FDD TDD

Number of

samples

Capacity

(user/MHz/cell)

Number of

samples

Capacity

(user/MHz/cell)

(A)

Indoor Hotspot 50 3 140 2 137

Urban Micro 40 3 80 2 74

Urban Macro 40 3 68 2 65

Rural Macro 30 3 91 2 86

(C)

Indoor Hotspot 50 3 131 3 130

Urban Micro 40 3 75 3 74

Urban Macro 40 3 69 3 67

Rural Macro 30 3 94 3 92


30/133

LTE-Advanced


Mobility Traffic Channel Link Data Rates

Rel-8 LTE can meet all the requirements

LOS/

NLOSScenarios

ITU

requirement

Median

SINR

(dB)

FDD TDD

Number of

samples

UL spectrum

efficiency

(bps/Hz)

Number of

samples

UL spectrum

efficiency

(bps/Hz)

Antenna conf.

1X4, NLOS

Indoor Hotspot 1.0 13.89 7 2.56 4 2.63

Urban Micro 0.75 4.54 7 1.21 4 1.14

Urban Macro 0.55 4.30 7 1.08 4 0.95

Rural Macro 0.25 5.42 7 1.22 4 1.03

Antenna conf.

1X4, LOS

Indoor Hotspot 1.0 13.89 4 3.15 2 3.11

Urban Micro 0.75 4.54 4 1.42 2 1.48

Urban Macro 0.55 4.30 4 1.36 2 1.36

Rural Macro 0.25 5.42 4 1.45 2 1.38


31/133

Overview of LTE-Advanced Technologies

Outlining of candidate technologies for LTE-Advanced

LTE enhancement areas for LTE-Advanced

Emerging technology areas for LTE-Advanced


32/133

LTE-Advanced

Outline of Candidate Technologies for LTE-A

Emerging technologies for LTE-Advanced Multi -hop transmission (relay) Multi -cell cooperation (CoMP: Cooperative Multipoint Tx/Rx)

Heterogeneous cell overlay

Self-organizing network

Enhancements from LTE Rel-8/9 Bandwidth/spectrum aggregation

Contiguous and non-contiguous Control channel design for UL/DL

MIMO enhancement Extended utilization of antennas (increasing the number of layers) UL SU-MIMO Enhanced UL/DL MU-MIMO

Hybrid multiple access scheme for UL Clustered SC-FDMA in addition to SC-FDMA

DL/UL Inter-cell Interference Management


33/133

LTE-Advanced

LTE Enhancement Areas for LTE-AdvancedSpectrum Aggregation Advanced MIMO

High-order MIMO

EnhancedDL/UL MU-MIMO

UL SU-MIMO

FFR & Power Control

A

A

A

Frequency

Power Spectral Density

B

B

C

C

D

D

D

Reuse 1 Reuse 1/3

B C

Sector 1

Sector 2

Sector 3

UL Hybrid Multiple Access

Cluster

IFFTP/S

Modulation

symbols

Time Domain

signalS/PDFT

:mapping to a RB


34/133

LTE-Advanced

Emerging Technologies for LTE-AdvacedMultihop Transmission (Relay) Multi-cell Cooperation (Collaborative MIMO)

Self Organizing Network (SON) Heterogeneous Cell Overlay

Pico eNB

Femto eNB

Relay eNB

Macro eNB

X2

Interne

t

Mobile

Core

Network

Femto-cellController


35/133

LTE-Advanced

LTE-Advanced Improvements

A schematic view on LTE-Advanced improvements

LTE-Advanced

LTE

Higher OrderMIMO

SpectrumAggregation

CoMP

CoMP

Coverage Extension

HeNB/Relay

eNodeB

Data rate

SON


36/133


37/133

LTE-Advanced

MIMO Enhancement for LTE-Advanced

DL MIMO enhancements

Design issues 8 Tx antennas

RS structure to support 8 Tx antennas DM RS

CSI RS

#of codewords

Codebook design Txdiversity in case of 8 Tx antennas

MU-MIMO enhancement scheme

UL MIMO enhancements

Design issues UL SU-MIMO transmiss ion

Up to 4Tx antenna Reference signal design

Number of codewords

Tx diversity

UL MU-MIMO enhancement


38/133

LTE-Advanced

Uplink Multiple Access

Motivation

Problems of SC-FDMA PAPR/CM gain is not so crucial for

UE without power limitation problem Restricted flexibility due to single-

carrier property in scheduling andcontrol channel design

However, low PAPR/CM of SC-FDMA at power-limited situation is

still very important Uplink Hybrid Multiple Access of

Clustered SC-FDMA and SC-FDMA Clustered SC-FDMA transmission

for more flexible scheduling Non-contiguous resource allocation

should also be supported forPUSCH transmission from UE withsufficient amount of powerheadroom both in absence andpresence of spatial multiplexing

SC-FDMA transmission forpower-limi ted UEs Support of low PAPR/CM property

IFFTP/S

Time-domainsignal

: mapping to a RB

IFFTP/S

IFFT

P/S

S/PRE

mapping

S/PRE

mapping

Time-domainsignal

Time-domain

signal

ModulationSymbols

for TrBlk B

ModulationSymbols

for TrBlk C

DFT

S/PRE

mappingDFT

DFT

ModulationSymbols

for TrBlk AClustered-

DFTsOFDM

Clustered-DFTsOFDM

Clustered-DFTsOFDM


39/133

LTE-Advanced

Relay [1]

Several types of data transmission between eNB and

UEUE Relaying

Direct inter-UE connectivity

Autonomous ad-hoc network configuration

and management

Support of emergency call status

Relay Node Tx/Rx

Remote relay node Tx/Rx

Coverage extension and throughput

enhancement

Conventional UE-eNB Tx/Rx

Conventional single-hop Tx/Rx between UE

and eNB as a basic connection scheme

Wireless link

connectioneNB

Relay

Node

Relay

Node

Out of focus in LTE-Advanced study

Main focus in LTE-Advanced study


40/133

LTE-Advanced

Relay [2]

Exemplary use case for relay


41/133

LTE-Advanced

CoMP [1]

CoMP stands for

coordinated multipoint

transmission

CoMP in Rel-10 time

frame

Agreed not to pursuestandardized CoMPsolution at least duringRel-10 time frame

However, new study itemfor CoMP was created

during last RAN plenarymeeting in March


42/133

LTE-Advanced

CoMP [2]

CoMP categories under

consideration

Joint Processing

Data is available at each point inCoMP cooperating set

J oint Transmission

Dynamic Cell Selection Coordinated

Scheduling/Beamforming (CS/CB)

Data is only available at serving cell


43/133

LTE-Advanced

CoMP [3]

Joint Transmission

Data to a single UE is available at multiple transmission points

PDSCH transmission from multiple points (part of or entire CoMPcooperating set) at a time Coherently or non-coherently

To improve the received signal quality and/or cancel actively interferencefor other UEs

Dynamic Cell Selection

CoMP transmission point from a single point Can change dynamically within the CoMP cooperating set.

Cooperative Scheduling/ Beamforming (CS/CB)

Data is only available at serving cell

User scheduling/beamforming decisions are made with coordinationamong the CoMP cooperating set.

CoMP transmission point : serving cell


44/133

More Details on LTE-AdvancedComponent Technologies

Spectrum and carrier aggregation

Relay

Enhanced DL MIMO

UL MIMO CoMP


45/133

Spectrum and carrier aggregation

Overview

Carrier Types

MAC-PHY interface

Uplink Multiple Access Uplink Control Channel

Downlink Control Channel

UL Power control


46/133

LTE-AdvancedLTE/MIMO 46

Overview [1]

Carrier aggregationSupport wider bandwidth

Two or more component carriers

Up to 100MHz and for spectrum aggregation

Each component carrier limited to a maximum of 110 RBs

Using Rel8 numerology

Carrier aggregation type

Contiguous

Non-contiguous


47/133

LTE-Advanced

Overview [2]

Concept of carrier aggregation

Contiguous component carrier

Non-contiguous component carrier

Frequency

LTE

bandwidth

Frequency

Aggregated bandwidth


48/133

LTE-Advanced

Overview [3]

Deployment scenarios in RAN4 Intraband cont iguous CA

Originally, intraband contiguous CA scenario was proposed only forTDD, but it was agreed also for FDD afterwards for the sole reason ofsatisfying ITU-R requirement

E-UTRA

CA

Band

E-UTRA

operating

Band

Uplink (UL) band Downlink (DL) band

Duple

x

mode

UE transmit / BS receiveChannel

BW MHz

UE receive / BS transmitChannel

BW MHzFUL_low (MHz) FUL_high (MHz)FDL_low (MHz) FDL_high

(MHz)

CA_40 40 2300 2400 [TBD] 2300 2400 [TBD] TDD

CA_1 1 1920 1980 [TBD] 2110 2170 [TBD] FDD


49/133

LTE-Advanced

Overview [4]

Interband non-contiguous CA

TBD bandwidth will be finally decided after having RAN4discussion

E-UTRA

CA

Band

E-UTRA

operating

Band

Uplink (UL) band Downlink (DL) band

Duple

x

mode

UE transmit / BS receiveChannel

BW MHz

UE receive / BS transmitChannel

BW MHzFUL_low (MHz) FUL_high (MHz)FDL_low (MHz) FDL_high

(MHz)

CA_1-51 1920 1980 [TBD] 2110 2170 [TBD]

FDD5 824 849 [TBD] 869 894 [TBD]


50/133

LTE-Advanced

Overview [5]

UE capabili ty regarding carrier aggregation

LTE-A UE Simultaneous transmission/reception on multiple component carrier

Depends on the transmission/reception capability

Rel8 UE Transmission on a single component carrier only

Characteristics of component carrier It shall be possible to configure all component carr iers LTE Release 8 compatible at least

when the aggregated numbers of component carriers in the UL and the DL are same

Consideration of non-backward-compatible configurations of LTE-A component carriers is notprecluded(CC only for LTE-A)

Frequency

System bandwidth,

e.g., 100 MHzCC, e.g., 20 MHz

UE capabilities100-MHz case

40-MHz case

20-MHz case(Rel. 8 LTE)


51/133

LTE-Advanced

Carrier Types

Backward compatible carrier

A carrier accessible to UEs of all existing LTE releases

Can be operated as a single carrier (stand-alone) or as a part ofcarrier aggregation

For FDD, backwards compatible carriers always occur in pairs, i.e.

DL and UL Non-backward compatible carrier

A carrier not accessible to UEs of earlier LTE releases

Can be operated as a single carrier (stand-alone) from the duplexdistance

Otherwise, as a part of carrier aggregation


52/133

LTE-Advanced

MAC-PHY Interface

From a UE perspective

There is one transport block (in absence of spatial multiplexing) One hybrid-ARQ entity per scheduled component carrier.

Each transport block is mapped to a single component carrier

A UE may be scheduled over multiple component carr ierssimultaneously.

Channelcoding

Modulation

RB mapping

Component carrier 1 Component carrier 2

20MHz 20MHz

transport block

Channelcoding

Modulation

RB mapping

transport block

One UE


53/133


54/133

LTE-Advanced

Uplink Control Channel

PUCCH design

Rel10 design supports up to 5 DL CC

Consider extendability to larger number of DL CC in the future

All ACK/NACK for a UE can be transmitted on PUCCH in absence ofPUSCH transmission

Simultaneous A/N on PUCCH transmission from 1 UE on multiple UL CCs

is not supported A single UE-specific UL CC is configured semi-statically for carrying PUCCH

A/N

Method for assigning PUCCH resource(s) for a UE on the above single ULcarrier in case of carrier aggregation

Implicit / Explicit / Hybrid: FFS

Note that for a CA-capable UE that is configured for single UL/DL carrier-pair operation, single-antennaPUCCH resource assignment shall be done as per Rel-8.

A s ingle UE-specif ic UL CC is conf igured semi-stat ical ly for carrying

PUCCH A/N, SR, and periodic CSI from a UE

Concept of primary carrier


55/133

LTE-Advanced


One SR per UE transmitted on PUCCH

Semi-statically mapped onto one UE specif ic UL CC

Periodic CSI reporting for up to 5 DL CC supported

Semi-statically mapped onto one UE specif ic UL CC

Following Rel8 principles for CQI/PMI/RI

Consider ways to reduce reporting overhead, e.g. DL CC cycling

Consider ways to support extending CSI payload


56/133

LTE-Advanced


Further discussion points for ACK/NACK transmission

Method(s) for A/N multiplexing How many simultaneous PUCCH signals?

PUCCH format 1b with SF reduction to 2 or 1

Channel selection with appropriate modification

PUCCH format 2

New PUCCH signal/format (e.g. DFT-S-OFDM based)

A/N bundling within / across CCs

Also consider TDD

P P P

PUCCH

PUCCH

PUCCH

PUCCH

PUCCH

PUCCHA/N A/N A/N

P P P

PUCCH

PUCCH

A/N A/N A/N

Bundling

P P P

PUCCH

PUCCHA/N A/N A/N Join t cod ing

Multiple resources transmission Bundling J oint coding


57/133

LTE-Advanced


CQI (Channel Quality Indication)

Multiple CQIs on single component carrier Multiple resources transmission

J oint coding

TDM

PUCCH

PUCCH

PUCCH

PUCCH

PUCCH

PUCCHCQI CQI CQI

DL CC #0 DL CC #1 DL CC #2DL CC #0 DL CC #1 DL CC #2

PUCCH

PUCCH

CQI CQI CQI

Joint coding

Multiple resources transmissionJ oint codingPU

CCH

PUCCH

PUCCH

PUCCH

PUCCH

PUCCH

CQI CQI CQI

DL CC #0 DL CC #1 DL CC #2

subframe#n

subframe#n+1

subframe#n+2

Time

TDM


58/133


59/133

li k l h l


60/133

LTE-Advanced

Downlink Control Channel

PHICH transmission

Re-use PHICH physical transmission aspects from Rel8

Orthogonal code design, modulation, scrambling sequence, mapping to REs

PHICH transmitted only on the DL CC used to transmit the UL grant

PHICH resource mapping rules:

For 1-to-1 or many-to-1 mapping between DL and UL without CIF

Reuse Rel8 mapping

For many-to-1 UL:DL mapping or many-to-1 mapping between DL and ULwith CIF

Single set of PHICH resources shared by all UEs (Rel-8 to Rel-10)

DM RS cyclic shift mechanism remains available and can be used to reduce collisionprobability

Working assumption to be confirmed at RAN1#60bis if no fundamental problemidentified:

Further discussion point

Additional standardised mechanism for handling PHICH collisions needed?


61/133


62/133

U li k P C t l


63/133

LTE-Advanced

Uplink Power Control

PHR

Per CC

FFS whether or not PHR is per channel (i.e. PUSCH / PUCCH) withineach per-CC PHR

Max power scaling

Starting point:

PUCCH power is prioritised; remaining power may be used by PUSCH (i.e.PUSCH power is scaled down first, maybe to zero)

scaling is per channel

Detailed formula is FFS

Power control for multiple antennas: FFS


64/133

Relay

Overview

Type 1 Relay

Type 2 Relay

Resource Partioning for Relay-eNB link

Access-Backhaul Partitioning

Backward compatible backhaul partitioning

Backhaul Resource Assignment

R-Channel design


65/133

T 1 R l


66/133

LTE-Advanced

Type 1 Relay

Control Cells of its own

It control cells, each of which appears to a UE as a separate cell distinctfrom the donor cell

Has unique physical-layer cell identity (defined in Rel-8)

Shall transmit its own synchronization, reference symbols, ..

The same RRM mechanisms as normal eNB

No difference in accessing cells controlled by a relay and cells controlledby a normal eNB from a UE perspective

Shall appear as a Rel-8 eNB to Rel.8 UE

To LTE-A UEs, it should be possible for a type 1 relay node to appeardifferently than Rel.8 eNB to allow for further performance enhancement

UE shall receive scheduling information and HARQ feedback directly fromthe relay node and send its control channels (SR/CQI/ACK) to the relaynode

Self-backhauling, in-band relay

T 2 R l


67/133

LTE-Advanced

Type 2 Relay

Part of the donor cell

It does not have a separate Physical Cell ID

Would not create any new cells

It is transparent to Rel-8 UEs;

A Rel-8 UE should not be aware of the presence of a type 2 relay node

At least part of the RRM is controlled by the eNB to which thedonor cell belongs

It can transmit PDSCH

At least, it does not transmit CRS and PDCCH

L2 relay, smart repeaters, decode-and-forward relays

R P ti i f R l NB Li k


68/133

LTE-Advanced

Resource Partioning for Relay-eNB Link

Link definit ion

Backhaul link

DL backhaul : eNB-> RN

UL backhaul : RN -> eNB

Access link

DL access : RN -> UE UL access : UE -> RN

R P ti i f R l NB Li k


69/133

LTE-Advanced

Resource Partioning for Relay-eNB Link

Inband Backhauling of Relay

eNB-to-relay link operates in the same frequency spectrum as therelay-to-UE link

In this case, half duplex relay operation is more feasible

Simultaneous eNB-to-relay and relay-to-UE transmissions on the same

frequency resource may not be feasible Due to relay transmitter causing interference to its own receiver

Unless sufficient isolation of the outgoing and incoming signals is provided

Similarly, relay may not be possible to receive UE transmissionssimultaneously with the relay transmitting to the eNB

Therefore, resource partioning scheme should be taken intoaccount in case of inband half duplex relay


70/133

Access Backhaul Partitioning


71/133

LTE-Advanced


Example of UL resource TDM partitioning

No TX

UL RX

Relay UL TX

Relay UL RX

UL TXR-UE UL TX

subframe

UL TX

No RX

e.g. blocked subframe

UL RXeNB UL RX

Access Backhaul Partitioning


72/133

LTE-Advanced


Illustration

eNB

RN

UE2

DL (F1)

DL (F1)UL (F2)

UE1

DL (F1)UL (F2)

F1F2

UL (F2)

F1: DL frequency (FDD)F2: UL frequency (FDD)

One link active at a timeOne link active at a time


73/133



74/133

LTE-Advanced


Backhaul Subframe allocation

At the RN, the access link DL subframe boundary is aligned with the backhaul linkDL subframe boundary, except for possible adjustment to allow for RNtransmit/receive switching

The set of DL backhaul subframes

During which DL backhaul transmission may occur

Semi-statically assigned

The set of UL backhaul subframes During which UL backhaul transmission may occur,

Can be semi-statically assigned,

Or implicitly derived from the DL backhaul subframes using the HARQ timingrelationship

R-PDCCH (Relay Physical Downlink Control CHannel)

R-PDCCH is used to assign resources for the DL backhaul data

Dynamically or semi-persistently assign resources May assign DL resources in the same and/or in one or more later subframes.

R-PDCCH is used to assign resources for the UL backhaul data Dynamically or semi-persistently assign resources

May assign UL resources in one or more later subframes.

R Channel Design (TR 36 814)


75/133

LTE-Advanced

R-Channel Design (TR 36.814)

R-PDCCH resources

PRBs for R-PDCCH transmission is semi-statically assigned Resources for R-PDCCH transmission within semi-statically assigned may

vary dynamically between subframes Resources that are not used for R-PDCCH within the semi-statically

assigned PRBs may be used to carry R-PDSCH or PDSCH

R-PDCCH decoding

R-PDCCH transmitter processing (channel coding, interleaving,multiplexing, etc.) should reuse Rel-8 functionality to the extent possible Search space approach of R8 is used for the backhaul link

Use of common search space, which can be semi-statically configured (andpotentially includes entire system bandwidth

If RN-specific search space is configured, it could be implicitly or explicitlyknown by RN.

The R-PDCCH is transmitted starting from an OFDM symbol with inthe subframe that is late enough so that the relay can receive it.

R-PDSCH and R-PDCCH can be transmitted within the samePRBs or within separated PRBs.

R Channel Design


76/133

LTE-Advanced

R-Channel Design

Backhaul link reference signal

For R-PDCCH, For a given RN, R-PDCCH demodulation RS type (CRS or DM-RS) shall not

change dynamically nor depend on subframe type. Demodulate with

In normal subframes: Rel-10 DM-RS when DM-RS are configured by eNB Otherwise Rel-8 CRS

In MBSFN subframes, Rel-10 DM-RS Baseline may be modified (in relation to which OFDM symbols contain DM RS)

depending on RAN4 response on the timing.

For downlink shared data transmission on Un Same possibilities as for R-PDCCH

Further discussion point R-PDCCH multiplexing Backhaul link HARQ timing Detailed R-PDCCH design


77/133

Backhaul Link Timing: DL [2]


78/133

LTE-Advanced


Case 1: DL (-) timing offset

A fixed delay in addition to propagation delay



79/133

LTE-Advanced


Case 2 (DL): No offset, Switching t ime < CP



80/133

LTE-Advanced


Case 3 (DL): Global Tx timing sync

Cas3 3a: [(Tp


81/133


82/133

Backhaul Link Timing: UL [2]


83/133

LTE-Advanced

Backhaul Link Timing: UL [2]

UL timing: (-) time offset

Not listening to the symbol#13 (or SRS) in Uu link


84/133

Enhanced DL MIMO Transmission

DL RS: Overview

DL-RS: DM-RS

DL-RS: CSI-RS

DL MIMO: Overview

DL-MIMO: DL-MIMO in LTE-Advanced


85/133


86/133


87/133

DL-RS: DM-RS [1]


88/133

LTE-Advanced

DL RS: DM RS [1]

Characteristics

UE specific

Transmitted only in scheduled RBs and the corresponding layers:

Design principle is an extension of the concept of Rel-8 UE-specific RS (used for beamforming) to mult iple layers

RSs on different layers are mutually orthogonalRS and data are subject to the same precoding operation

No need to transmit precoding information

Per-PRB based channel estimation

Precoding granularity indication is FFS

Complementary use of Rel-8 CRS by the UE is not precluded

DL-RS: DM-RS [2]


89/133

LTE-Advanced

DL RS: DM RS [2]

DM-RS pattern for rank-1 and rank-2 Forward compatible DM-RS pattern design from LTE Rel-9 dual

layer beamforming

CDM between two layers

DM-RS pattern agreed for Rel-9 dual layer beamforming

Extended CP was not agreed and thus is not supported in conjunctionwith transmission mode 8 in Rel-9.

Note that this does not preclude a solution being introduced in a laterrelease

Normal subframe DwPTS (symbols >= 11) DwPTS (symbols


90/133

DL-RS: DM-RS [4]


91/133

LTE-Advanced

DL RS: DM RS [4] DM-RS pattern for rank5~8

Hybrid CDM+FDM DMRS patterns are adopted for rank 5-8 transmissionwith normal CP (normal subframe, DwPTS)

Same location with same density (24RE per PRB) as the rank3-4The length of OCC in time domain is 4 for both CDM groups

2 CDM group, OCC length=4

Multiple RB opt imization Followings are FFS

DM-RS pattern optimization according to the number of RBs allocated

Precoding granularity indication

Normal subframe DwPTS with 11,12OFDM symbols

DwPTS with 9,10OFDM symbols

DL-RS: CSI-RS [1]


92/133

LTE-Advanced

DL RS: CSI RS [1]

Baseline assumption for CSI-RS

CSI-RS is transmitted by puncturing data RE on both LTE Rel-8/9 andLTE-Advanced PDSCH Some performance impacts on the legacy Ues are inevitable

Loss of information due to puncturing Interference from CSI-RS

Uniform frequency spacing and periodic time domain transmission Agreed to transmit all the CSI-RS for every antenna port within the same

subframe Overhead assumption

CSI-RS density in frequency domain 1 RE per PRB for 2, 4 and 8 antennaport

CSI-RS density in time domain Multiple of 5 msec is baseline for further evaluations. 10ms periodicity is prioritized

Assuming 10ms periodicity, CSI-RS overhead can be calculated as 0.06%(1/1680) (8 antenna port = 0.48 %) Time density: 1 symbol every 10ms per antenna port 1/140 Frequency density: 1 RE per PRB 1/12

DL-RS: CSI-RS [2]


93/133

LTE-Advanced

DL RS: CSI RS [2]

Relationship between CSI-RS and Rel-8 CRS

No mixed use of Rel-8 CRS and Rel-10 CSI RS for a configured Rel-10CSI measurement of a given cell at Rel-10 UE (for all possible number ofantenna ports in the cell) For the configured CSI measurement the UE measures either on Rel-8 CRS or

on Rel-10 CSI RS for the given cell

8 Rel-10 CSI RS can be configured for Rel-10 CSI measurements in agiven cell

For this case of Rel-10 CSI measurements, only the 8 Rel-10 CSI RS are usedfor the CSI measurements corresponding to the given cell

CSI RS are punctured into the data region of normal/MBSFN subframes However, independent antennea configuration is possible

DL-RS: CSI-RS [3]


94/133

LTE-Advanced

DL RS: CSI RS [3]

Further agreement in RAN1 wi th respect to CSI-RS

Full-power utilization is the design target. Send an LS to RAN4 asking about the feasibility of 9 dB boosting. Same data RE power between a data RE in the OFDM symbol containing CSI-RS

and a data RE in the OFDM symbol without CSI-RS/Rel-8 CRS is assumed within asubframe

Resource elements (REs) of CSI-RS are configured and/or tied to systemparameters for inter-cell orthogonality, i.e, no collision between CSI-RS Partial collision of CSI-RS for inter-cell randomization is not precluded.

CSI-RS pattern for {2,4,8}CSI-RS ports Port 0 is fully configured (subframe, OFDM symbol, frequency location) by L3 signaling and

/or tied to system parameters The other ports follow port0 (implicit) FFS if all ports have the same shift or different shift in time and frequency

For intra-cell CSI-RS, FDM/TDM/CDM/CSM needs further study. Study RE muting, i.e., no coll ision between CSI-RS and data, for multi-cell CSI

measurement Consider the impact of muting on UE interference measurement

Consider the impact on Rel-8 UE

Power reallocation of muted REs is FFS


95/133

DL-MIMO: Overview


96/133

LTE-Advanced

DL MIMO: Overview

DL-MIMO in LTE-Advanced


97/133

LTE-Advanced

DL MIMO in LTE Advanced

The number of transmit antennas in DL: up to 8

Design issue

Number of codewords

Reference signal (RS)

Transmit diversity

Precoding

Multi-user MIMO (MU-MIMO)

Maximum number of codewords: 2

2 transport blocks in a subframe

Number of MCS fields: 2

Separate link adapation of two codewords


98/133

DL MIMO in LTE-Advanced


99/133

LTE-Advanced

DL MIMO in LTE Advanced

Transmit Diversity Scheme

Rel-8 TxD wi ll be reused with CRS in normal subframe

TBD: TxD definition in LTE-Advanced only subframe

Alt 1: rank-2 DRS supports SFBC

Alt 2: channel interpolation with the CRS in the next subrame PDCCHregion

Alt 3: no definition of TxD in LTE-Advanced only subframe

DL MIMO in LTE-Advanced


100/133

LTE-Advanced

O d a ced

MU-MIMO

In Rel-9, DM-RS based MU-MIMO scheme was decided Dynamic indication of DM-RS port is supported in case of rank 1 transmission

To enable scheduling of two UEs with rank-1 transmission using different orthogonal DMRS ports onthe same PDSCH resources

SU/MU assumption no explicit signaling of the presence of co-scheduled UE in case of rank 1 transmissions

in case of rank-1 transmission, the UE cannot assume that the other DM RS antenna port is notassociated with PDSCH assigned to another UE

Dynamic SU/MU switching in LTE-Advanced Switching between SU- and MU-MIMO transmission is possible without RRC

reconfiguration

Transparent vs. Non-transparent MU-MIMO Transparent here means that no downlink signalling is provided to indicate to a UE

whether a downlink transmission to another UE is taking place in the same RB.

No clear preference for transparent or non-transparent MU-MIMO at this stage.

If MU-MIMO were to be non-transparent, strongest possibilities to consider for downlinksignalling include:

whether / which DM-RS ports are used for other UEs

Power offset

DL-MIMO in LTE-Advanced


101/133

LTE-Advanced

Target design cri teria for 8Tx Codebook 8Tx codebook is now under discuss ion for feedback purpose only

Design criteria For rank >2, optimize for SU-MIMO only For rank


102/133

UL MIMO

UL MIMO: Overview

UL MIMO: Multiple Access Scheme

UL MIMO: Receiver for UL MIMO

UL MIMO: Multi-Antenna Support

UL MIMO: Reference Signal

UL-MIMO: Overview [1]


103/133

LTE-Advanced

[ ]

UL-MIMO in Rel8

UL MIMO was not supported for complexity reason 64QAM was introduced instead during Rel8 time frame

Only antenna switching Tx diversity is defined in Rel-8 LTE

MU-MIMO was supported in an implicit manner (specification transparent way)

LTE-Advanced

Agreed to employ SU-MIMO in LTE-Advanced Crucial in satisfying 3GPPs own peak spectrum efficiency requirement

The number of transmit antennas in UL Up to 4 transmit antenna will be supported

4 layer transmission

Design issue Multiple access scheme

Number of codewords Precoder design

Transmit diversity

UL-MIMO: Overview [2]


104/133

LTE-Advanced

[ ]

Necessity of Preserving CM

OFDM vs. SC-FDMA discussion in early LTE-Advanced SI phase SC-FDMA is agreed as an uplink multiplexing scheme

MIMO transmission should be implemented with SC-FDMA

SC-FDMA based MIMO transmission

CM can be one of design criteria for uplink MIMO scheme

Single antenna mode support In this mode, the UE behavior is same as the UE behaviour with single

antenna from eNBs perspective

Exact UE implementation is left to UE vendors (e.g., PA archiecture)

PUCCH and/or PUSCH and/or SRS transmission can be independently

configured for single uplink antenna port transmission Detail scenario and operation is FFS

UL single antenna port mode is the default operation mode beforeeNB is aware of the UE transmit antenna configuration

UL-MIMO: Multiple Access Scheme


105/133

LTE-Advanced

p

SC-FDMA vs. OFDMA

Complexity SC-FDMA: turbo SIC

OFDMA: maximum likelihood detector (MLD)

MLD is more complex in 16/64 QAM, especially for 4x4 configuration

Latency

Depends on computational complexity SC-FDMA and OFDMA may not give significant difference

Performance

OFDMA shows gain over SC-FDMA in high SNR range for 2x2 configuration

Similar performance for 2x4 configuration

OFDMA shows system level gain over SC-FDMA in 2x2 and 4x4 configuration

SC-FDMA was adopted for mult iple access scheme as UL MIMO

transmission

UL-MIMO: Receiver for UL MIMO


106/133

LTE-Advanced

Soft interference canceller (SIC): turbo SIC

Implementation flexibility: various algorithms

One implementation [1]: R1-083732


107/133

UL-MIMO: Multi-Antenna Support [2]


108/133

LTE-Advanced

pp

Candidates forTx diversity for PRACH

PVS, CDD, TSTD

Candidates for Tx Diversity for PUSCH

No consensus on the necessity of TxD in Rel-10 Identify target use cases where 2 TxD bring additional benefit, compared to single antenna

mode and SM mode

Following candidates are on the table

2 transmit antennas FSTD

STBC: special care of unpaired symbol due to SRS

Modified SFBC

Closed loop rank 1 precoding

4 transmit antennas

STBC + FSTD STBC + PSD

CDD + FSTD

Modified SFBC + FSTD

Closed loop rank 1 precoding



109/133

LTE-Advanced

pp

PUCCH TxD

2 Tx PUCCH transmit diveristy scheme Rel-8 PUCCH format 1/1a/1b: Spatial Orthogonal Tramsit Diveristy (SORTD) is applied

The same modulation symbol d(0) is transmitted on different orthogonal resources for differentantennas

Exact resource allocation: FFS

PUCCH format 2 TxD Three major camps for PUCCH format 2 :

No TxD, SORTD, STBC without slot hopping

4 Tx PUCCH transmit diversity: 2Tx TxD is applied (UE implementation issue)

Modulation symbol

Spreading with n_r0

Spreading with n_rM-1

n_r=(n_cs, n_oc, n_PRB) for PUCCH format 1

n_r=(n_cs, n_PRB) for PUCCH format 2Ant#0

Ant#M-1

d_0 (n)

d_0 (n)

d_0 (n)

.

.

.


110/133


111/133



112/133

LTE-Advanced

Precoder design for 4Tx

Separate design of each rank

No nested property

Alphabet in codebook element: from {1, -1, j, -j}

Antenna selection codebook elements in rank 1

Cubic metric preserving (CMP) codebook in rank 2 and rank 3 Identity precoding matrix in rank 4



113/133

LTE-Advanced

4Tx rank-1 codebook

Size-24: 16 constant modulus + 8 antenna pair turn-off vectors



114/133

LTE-Advanced

4Tx rank-2 codebook

Size-16: CM-preserving matrices

QPSK alphabet



115/133

LTE-Advanced

4Tx rank-3 codebook

Size-12 CMP codebook BPSK alphabet

4Tx rank-4 codebook

Single identity matrix

Index 0 to 3

Index 4 to 7

Index 8 to 11

100

010

001

001

2

1

100

010

001

001

2

1

100

001

010

001

2

1

100

001

010

001

2

1

001

100

010

001

2

1

001

100

010001

2

1

100

001

001

010

2

1

100

001

001010

2

1

001

100

001

010

2

1

001

100

001

010

2

1

001

001

100

010

2

1

001

001

100

010

2

1


116/133

UL-MIMO: Reference Signal [1]


117/133

LTE-Advanced

UL DM-RS in support of UL-MIMO

Precoded UL DM-RS 2Tx

rank 1-rank 2: precoded RS

4Tx

rank 1-rank2, rank 4: precoded RS

rank 3 : FFS, but potential agreement of precoded DM-RS in case of rank-3

Same precoding for DM RS and PUSCH

UL DM-RS multiplexing

Cyclic shift (CS) separation for DM-RS multiplexing

TBD: Orthogonal cover code (OCC) separation between slots for interferencesuppression

DM-RS sequence design for non-contiguous resource allocations Working assumption: Base sequence according to the whole allocation size and

split into clusters.


118/133


119/133

CoMP

Overview

Carrier Types

MAC-PHY interface

Uplink Multiple Access

Uplink Control Channel Downlink Control Channel

UL Power control


120/133

CoMP Category


121/133

LTE-Advanced

Joint Processing Data is available at each point in CoMP cooperating set

J oint Transmission Dynamic Cell Selection

Coordinated Scheduling/Beamforming (CS/CB) Data is only available at serving cell

Joint Transmission Data to a single UE is available at multiple transmission points

PDSCH transmission from multiple points (part of or entire CoMP cooperating set) at a time Coherently or non-coherently To improve the received signal quality and/or cancel actively interference for other UEs

Dynamic Cell Selection CoMP transmission point from a single point Can change dynamically within the CoMP cooperating set.

Cooperative Scheduling/ Beamforming (CS/CB)

Data is only available at serving cell User scheduling/beamforming decisions are made with coordination among the CoMP

cooperating set. CoMP transmission point : serving cell

CoMP Operation- J oint Transmission


122/133

LTE-Advanced

CoMP Operation CS/CB


123/133

LTE-Advanced

) R1-092232, Summary of email discussion for CoMP Qualcomm

J oint Processing:Transparent vs. Non-transparent


124/133

LTE-Advanced

Transparent to UE

DL joint transmission is based on the dedicated reference signals (DRS)for demodulation

UEs need not know which eNBs participate in transmission

Easy to implement and minimal spec change

May cause performance degradation due to CRS and PDSCH collision

RE collision may be resolved by alignment among CoMP transmissionpoints

Non-transparent to UE

CRS and PDSCH RE mapping collision among transmission points

Enable resource mapping optimization

Increase overhead for DL control channels

Transmission Points : semi-statically (or dynamically) conf igured

J oint processing:Coherent vs. Non-coherent


125/133

LTE-Advanced

In terms of manner of the combination of signal from multiple

cells at UE Coherent transmission

Non-coherent transmission

Coherent transmission

UE could combine transmitted signal coherently

Network obtains channel state information of all the cooperating cell sites Phase correction + precoding

Phase factor obtained from feedback or calculated at network side

The transmitted signal from each cell is multiplied by a distinct phasefactor

Global precoding

Non-coherent transmission

Signal arriving at UE is unable to combine coherently

Precoding Codebook for CoMP


126/133

LTE-Advanced

Global precoding (joint design)

A single super-cell codebook is designed considering multiple points. A codebook needs to be designed for each combinations

Number of cooperating points

Number of transmit antennas

Number of layers

The performance is upper bound of all precoding schemes for CoMP High Complexity

Large global codebook to quantize

Codebook varies with the size of CoMP cells

Local precoding (disjoint design)

A single super-cell codebook is composed by the N(number of cooperatingpoints) single-cell codebook

Local precoding design is simpler

The performance is worse than that of global precoding

Cell Clustering for CoMP


127/133

LTE-Advanced

UE-specif ic Clustering

Cluster of coordinated cells chosen based on the preference of the UE Largest throughput gain Scheduling among all eNBs in the system needed Excessive Backhaul overhead

Fixed Clustering

Simple in terms of implementationThroughput gain obtained is limited

Hybrid UE-specific clustering UE specific with Networkassistance Cluster of eNB serving a particular UE is a subset of a larger fixed cluster

Throughput gain Reduce scheduling complexity and backhaul demand

Semi-statically (or dynamically) configured

Feedback in Support of DL CoMP


128/133

LTE-Advanced

CoMP Feedback mechanisms

Explicit channel state/statistical information feedback Channel as observed by the receiver, without assuming any

transmission or receiver processing

Implicit channel state/statistical information feedback

Use hypotheses of different transmission and/or reception processing,

e.g., CQI/PMI/RI

Channel reciprocity

UE transmission of SRS can be used for CSI estimation at eNB

UE CoMP feedback reports target the serving cell on UL resources from serving cell

Explicit Feedback


129/133

LTE-Advanced

Channel part

For each cell in the UEs measurement set that is reported in agiven subframe, one or several channel properties are reported

Channel properties include (but are not limited to) the following

Channel matrix short term (instantaneous)

Transmit channel covariance

Inter-cell channel properties may also be reported

Noise-and interference part

Interference outside the

Cells reported by the UE

CoMP transmission pointsTotal receive power (Io) or total received signal covariance matrix

Covariance matrix of the noise-and-interference

Implicit Feedback


130/133

LTE-Advanced

Hypotheses at the UE and the feedback

based on one or a combination of two or more of the following, e.g.: Single user vs. Multi user MIMO

Single cell vs. Coordinated transmission Within coordinated transmission : Single point (CB/CS) vs. multi-point (J P)

transmission

Within J oint processing CoMP

Subsets of transmission points or subsets of reported cells (J oint Transmission) CoMP transmission point(s) (Dynamic Cell Selection)

Transmit precoder (i.e. tx weights)

J P : multiple single-cell or multi-cell PMI capturing

CB/CS : single-cell or multiple single-cell PMIs

Other types of feedbacks, e.g. main Multi-cell eigen-component, instead ofPMIs are being considered

Receive processing (i.e. rx weights)

Interference based on particular tx/rx processing

Reference [1]


131/133

LTE-Advanced

[1] ITU-R, Revision 1 to Document IMT-ADV/2-E, Submission andevaluation process and consensus building

[2] 3GPP, RP-08099, Proposed schedule for the submission of LTE-Advanced to ITU-R as a candidate for IMT-Advanced, AT&T et. Al

[3] ITU-R, Addendum 2 to circular letter 5/LCCE/2[4] ITU-R, Report ITU-R M.2133 Requirements, evaluation criteria, and

submission templates for the development of IMT-Advanced

[5] ITU-R, Report ITU-R M.2134 Requirements related to technicalsystem performance for IMT-Advanced Radio interface(s)[6] ITU-R, Report ITU-R M.2135 Guidelines for evaluation of radio

interface technologies for IMT-Advanced[7] 3GPP, RP-091000, Release 10 time plan[8] ITU-R WP5D/291, Initial 3GPP submission of a candidate IMT-

Advanced technology[9] ITU-R WP5D/496, AN INITIAL TECHNOLOGY SUBMISSION OF

3GPP LTE RELEASE 10


132/133


133/133

Thanks !!