1

The UR of 5G

Dr. Chih-Lin I

CMCC Chief Scientist, Wireless Technologies

CMRI, China Mobile

IEEE CQR Emerging Technology Round Table

May 14 2018, Austin, Texas, US

2

2

Internet of

Everything

Service

Industry

Education Home

Transport

Agriculture

3 Major Application Scenarios

Cross-industry convergence

Requirements

5G Vision, Requirements, and Verticals

Information a Finger Away

Everything in Touch

Everywhere

NB-IoT/eMTC as a start Across industry

3

3

Latency

Data rate

1ms

5ms

10ms

20ms

25Mbps 125Mbps 250Mbps 1.5Gbps

Substation protection & management

1ms

Industrial control,

Transporter automatic control

1~10ms, >99.999%

Remote driving

5ms, >99.999%

VR/AR applications in the

Clouds

5~10ms

4K video

Emergency aid, remote surgery

Cloudy robot (image/speech processing and interaction)

Facility inspection, Electricity emergency communication

20ms, >99.999%

Image transmission of UAV:

8K 2D

UL 120Mbps

20ms

Advanced VR in the Clouds

(Image: 12K 2D)

DL 250Mbps

20ms, >99.999%?

Image transmission of UAV:

24K 3D

UL 1.4GMbps

20ms

Sensor-based applications in

connected vehicle networks

End-to-End 1Gbps

10ms Ultimate VR in the Cloud

(Image: 24K 3D)

DL 1.4Gbps

10ms, >99.999%?

AR/VR/HD 4K

Connected UAV

Intelligent Connected Vehicle

Smart grid

Smart medical treatment

Industrial Internet

Cloudy Robot

Ultra reliability

General reliability

5G Use Cases: Ultra Reliability with Different Latency & Data Rate Requirements

4

4

Embracing Verticals

Intelligent

Could-Robot

Connected

Droned

Sharing Bikes

Mechanical arm

Power grid and oil pipeline monitoring

Industrial factory

5G mHealth Water tank monitoring Cellular

UAV Intelligent

Airport

Ground-to-air communication

First Aerial Internet SUMMIT in

Zhangjiakou, Mar 2018

Traffic Warden

Cloud UAV platform

Secure & Efficient

connected service

“Airplane mode”

ended in Jan

2018 in China

Tech Test

since 2013

CMCC IoX Demo in MWC2018

Collaboration w/

multiple airports

5

5

Rethink Fundamentals (2011)

Rethink Protocol Stack

Rethink Fronthaul

Rethink Base Station

Rethink Ring & Young

RAN

“Towards Green & Soft” IEEE WCNC Keynote, Apr.8, 2013

“SDX: How Soft is 5G?”, IEEE WCNC Keynote, Mar. 21,2017

“Towards Green & Soft: A 5G Perspective” IEEE Comm. Magazine, Vol.52, Feb.2014

“5G: rethink wireless communication for 2020+”, Philosophical Trans. A. 374(2062), 2015

“On big data analytics for greener and softer RAN,” IEEE Access, vol.3, Mar. 2015.

“New paradigm of 5G wireless internet”, IEEE JSAC, vol.34, no.3, March 2016

“Big Data Enabled Mobile Network Design for 5G & Beyond,” IEEE Comm. Magazine., vol. 55, no. 9, Jul.2017.

“Big Data Driven Intelligent Wireless Network: Architecture, Use Cases, Solutions and Future Trends ,” IEEE VT Magazine, 2017

CT/DT/IT Convergence Open Source Business Model

Green Communication Research

Center established in Oct. 2011,

initiated 5G Key Tech R&D. Green Soft

Rethink Air Interface & Spectrum

Rethink Signaling & control

Rethink Shannon (& Nyquist?)

AI

To enable wireless signal to “dress for the occasion” via SDAI

To start a green journey of wireless systems, EE/SE

To explore structured overlap????

To make network application/load aware

Embracing verticals How it affects the traditional SDOs? What’s Big Data’s role in 5G era

For no more “cells” via C-RAN

To enable Soft RAN via NGFI

To make BS “invisible” via SmarTile

To enable User Centric Cell and flexible AI via MCD

Efficiency Agility

6

6

SDX based 5G Arch: SBA, C-RAN/NGFI, SDAI

Soft Transport Network

Soft CN

Soft RAN

Serviced based Arch,

Network Slice, NFV

Ultra wide BW, lower latency,

Higher timing precision

UCN: C-RAN, CU/DU design

Flexible/configurable AI

RAN Restructure, CN-RAN Repartition , Turbo Charged Edge , Network Slice as a Service (2014)

(S)PTN PON

Unified RAN arch+ Common high layer protocol

(UCN, enabled by C-RAN/NGFI)

SDAI (Software Defined Air Interface) Low Freq.

New RIT

High Freq.

RIT

mMTC

RIT

uRLLC

RIT

Low-latency &

high-reliability Seamless wide-area

coverage

Hotspot &

high data rate

Low-power &

m-connections

5G CN

O &

M

NSSF (Network Slice Selection Function), introduced to support flexible deployment,

operation & maintenance of diverse network slices

(Apr., 2017) EC

MEC

DU

DU

CU-U

CU-U CN-U

CU-C CN-U CN-C

CN-C

超低延迟

URLLC

延迟敏感

eMBB

AR/VR

Industry

DU(s) CU-U CU-C

Video

CN-U 延迟不敏感

eMBB/mMTC

Web CN-C

CU-C

V2X

7

7

A flexible, efficient, scalable and programmable

network towards to “Telecomm 4.0” era

Lead in 5G Network Arch design (Serviced based architecture agreed in 3GPP SA2 #121, May 2017， TR 23.799 )

CMCC delegate as Rapporteur for R-14 SI/R-15 WI

NovoNet: True Convergence of CT and IT

CN Transformation: Service Based Architecture, Telecom 4.0

4G Architecture by equipment: rigid network

Function split &

integrate

8

8

Reliability Progress on CN

Reliability Progress in Rel-15 Objective of Reliability in Rel-16

AMF management with reliability

UDSF Unstructured Data Storage Function

Improve system reliability by decoupling data computing and data

storage. It enables flexible management of lifecycle for computing

logic in VM.

Service Name Description

Unstructured Data

Management This service allows NF service consumers to

retrieve, create, update, and delete data

stored in the UDSF.

• AMF Addition/Update

• AMF planned removal procedure

- AMF planned removal procedure with UDSF deployed

- AMF planned removal procedure without UDSF

• Procedure for AMF Auto-recovery

Service Name Description

Namf_Commu

nication

Enable an NF to communicate with the UE and/or the

AN through the AMF; Enable SMF to request EBI

allocation to support interworking with EPS.

Namf_EventEx

posure

Enable other NFs to subscribe or get notified of the

mobility related events and statistics.

Namf_MT Enable an NF to make sure UE is reachable.

SI on eSBA [SP-180231]

Study further architectural support for highly reliable deployments,

considering:

- support for traceability & monitoring

- architectural aspects of automation and failover handling,

reusing, whenever applicable, the enablers for network

automation studied in FS_eNA.

- to support dynamic and automatic addition, update and planned

removal of CP NFs and/or services in virtualized environments,

by e.g., extension of the AMF related mechanisms that have

been specified in Release 15

- study service operation to avoid long-living UE-specific bindings

between service instances, e.g., by separating functional

processing from state repository or other mechanisms

SI on eURLLC in 5G CN [TR 23.725]

• Supporting high reliability by redundant transmission in user plane

• Supporting low latency and low jitter during handover procedure

• Enhancement of Session Continuity during UE mobility

• QoS Monitoring to assist URLLC service

9

9

C-RAN: Revolutionary Evolution of RAN

…

RRU

RRU

RRU

RRU

RRU

RRU

RRU

Virtual BS Pool

Distributed RRU

High bandwidth optical transport

network

Real-time Cloud for centralized processing

…

“Soft BS ” in C-RAN virtualization/Cloudification

C-RAN has been deemed as a 5G essential enabling element (2011)

F1-C F1-U F1-C F1-U

gNB

Xn/X2

NG/S1-U

gNB-CU

RRC

PDCP-C

SDAP

PDCP-U

gNB-DU gNB-DU

RLC

MAC

PHY

RLC

MAC

PHY

CP UP???

CU/DU based two-level RAN Arch

• CU-DU Arch identified in RANP 75 (Mar 2017)

• E1 SI approved in RANP 76 (June 2017)

• E1 WI approved in RANP 78 (Dec 2017)

Centralized Control and/or Processing

Collaborative Radio, Real-Time Cloud , Clean System

10

10

RAN Transformation: a Journey

2012-2013 2014

R&D on C-RAN

baseband pool 1, Design, development & test

on front-end accelerator

2, First soft 4G BS PoC based

on COTS platform

3, First field trial in the

commercial networks

2016 2015

C-RAN PoC development 1, OTA test with commercial EPC ,

RRU & UE

2, Proposal of NGFI (xHaul)

concept

3, Proposal of CU-DU arch

C-RAN field trials 1, Large-scale field trials in 10+

cities

2, Virtualized C-RAN PoC demo

3, Evaluation of NGFI & design

of CU/DU arch

4. Established IEEE 1914 WG

5G C-RAN 1, Continuous refinement on design

of CU-DU arch & the interface

2, In-house PoC develop of gNB with

CU-DU, MANO & cloud platform

3, Carrier-grade cloud platform

proposal accepted by Openstack

2017 2018

5G smart cloud BS 1, C-RAN Alliance launched & CU-

DU arch accepted by 3GPP

2, 1st proposal of RDA concept w/

AI-based wireless big data arch

3, In-hours PoC development on

cloud-based CU-DU with demo with

commercial RRU&UE

5G O-RAN： 1, RDA

2, AI

3, MEC

4, ……

PCIe CPRI CN RT-Linux+ Driver

CU_DU VM

SmarTile Front-End

F1-C F1-U F1-C F1-U

gNB

Xn/X2

NG/S1-U

gNB-CU

RRC

PDCP-C

SDAP

PDCP-U

gNB-DU gNB-DU

RLC

MAC

PHY

RLC

MAC

PHY

CP UP???

CU-DU Arch identified

in RANP (Mar 2017)

11

11

Option2 identified in 3GPP RAN3 #95bis in Apr 2017 [F1 interface]

CU/DU function split: 8 arch options + NG interface definition

Study on various split options and give a preferred recommendation

The proposal of NGFI leads to the CU-DU architecture

PDCPLow-

RLC

High-

MAC

Low-

MAC

High-

PHYLow-PHY

PDCPLow-

RLC

High-

MAC

Low-

MAC

High-

PHYLow-PHY

Option 5Option 4 Option 6 Option 7Option 2Option 1

RRC

RRC

RF

RF

Option 8

Data

Data

High-

RLC

High-

RLC

Option 3

Non-ideal

fronthaul

optimal option

Massive

MIMO

optimal option

Normal

antenna

optimal option

Non-ideal

fronthaul

optimal option

A project under National Science & Technology Program, “Study and demonstration of 5G FH/BH solutions” ongoing, led by

CMCC with partners of Huawei, ZTE, Fiberhome and BUPT

SDAP

NGFI (xHual) : Essential Enabling Element of 5G C-RAN

Function split study, since 2012

White Paper on NGFI (x-Haul) released in June 2015, http://labs.chinamobile.com/cran.

• P1914.1 TF:

- Use case, Arch, scenarios, & requirements

Lead in IEEE 1914 WG, the 1st SDO for NGFI

• P1914.3 TF: Radio over Ethernet

encapsulation & mapping

• Now under the recirculation stage of sponsor

ballot, to be approved soon

• Specific objects & parameters defined for

split option 7-1, 7-2

• Enabling OPEN interface - Support I/Q in time & frequency (Option. 7-1 & 7-2)

- Legacy CPRI support

• LS to O-RAN FH WG to seek collaboration

on open FH interface specification

New project under discussion

12

12

Key Requirements of NGFI (xHaul) Transport in IEEE 1914.1

• Distance of CU-DU link: usually less than, yet could be

up to 100km

• Distance of DU-RRU: < 2km

• One DU ~ around 30 RRUs

• One CU ~ 300-600 DUs

• Multi-RAT, including legacy 4G (CPRI as FH)

• Optic line rate: 10Gbps, 25Gbps

• Various topologies: ring, star and daisy chain

• 1:1 protection required for CU-DU transport

• Recovery time of NGFI I: less than 10ms

• Recovery time of NGFI II: FFS

• Working temperature: -40~85 Celsius

UP

RF RRU

BBU

EPC

Backhaul

CPRI

CN

CU

DU

RRU

FH-II

BH

FH-I

UP

CP core

4G 5G

L1'

L1", L2-RT

L2-NRT, L3

13

13

From Coverage to Reliability in 5G NR

DL UL

Large scale antenna

• Multiple Beam for SSB and control channel

Wide beam

Narrow beam

• PDCCH: max AL, 16 CCEs, 3 dB improved

• Higher DMRS Density for PDCCH (<1dB)

• mMIMO: 128192 Ant elements (1.5dB), 64 TR

• Beam Recovery: robust design

......

...

Beam failure detection

N times measurement

Send beam recovery request

...

Receive beam recovery response

TRP

UE

• PUCCH repetition: UCI Repetition on PUCCH over multiple slots

PUSCH

NR UL slot

PUCCH

PUSCH

NR UL slots

PUSCH

PUCCH PUCCH

Long PUCCH Long PUCCH

• Higher power UE: 23dBm 26dBm (3dB)

• SUL: supplementary UL

• PUSCH repetition: UL Grant-free transmission

Periodicity

Repetition #1 Repetition #2 Repetition #K

… …

­ K-repetitions within a period, K={1,2,4,8}

­ Follow a configured RV sequence: {(0 0 0 0), (0 3 0 3), (0 2 3 1)}

>2dB

14

14

uRLLC Preemption in 5G NR

Slot-based transmission

uRLLC

Preemption indication via group-common PDCCH;

14-bit payload size for each

serving cell

slot n slot n+1

eMBB

PDCCH

M

2

…

…

1 2 … N

… … … … … …

M*N=14

Bitmap with each bit corresponds to a fraction of reference downlink resource

FFS in Rel-16:

- Compact DCI format

- PDCCH repetition

- New MCS/CQI table

- Service multiplexing for UL

…

UE1

UE 2

UE1 UE1

15

15

Reliability in 5G NR Higher Layer

PDCP duplication

• High reliability &Low latency

• Duplicated data are transmitted on different CCs

• Activated/ deactivated by MAC CE

• SRB duplication is supported as well

PDCP

RLC RLC

MAC MAC

CC1 CC2

PDCP duplication (DC)

PDCP

RLC RLC

MAC

CC1 CC2

PDCP duplication (CA)

HARQ & ARQ

• HARQ entity in MAC

Retransmission in PHY to enhance reliability

Flexible HARQ timing in 5G NR

• ARQ in AM RLC

Retransmission in AM RLC to enhance

reliability

RLC status report enhancement

PDCP

RLC

tx

RLC

rx

MAC

PHY

Status report

HARQ

Data duplication on

two legs

16

16

RDA: WBD enabled RAN AI

CN-CP CN-UP

RF

RRC

5G RAN

RF

CU-C

DU

CU-U

RF

Control Plane

User Plane

MAC

PHY

RLC

SDAP

PDCP

CU

E1

F1-C F1-U

Data Plane

D1

CUDA

DUDA

E2

E3

RDA

E4

F1'

RDA: RAN Data Analytics CUDA: CU Data Analytics DUDA: DU Data Analytics

17

17

UE QoS

UE Location Network configuration & traffic data

BSs Energy Model

INPUT

S-cell List

Traffic Distribution

Total Energy Forecast

OUTPUT

MCES (Multi-RAT Cooperation Energy-saving System)

GSMOMC/OSS

Multi-RAT Cooperation Energy-saving System

TD-SCDMA RNC

GSM BSC

TD-SCDMAOMC/OSS

TD-LTEOMC/OSS

eNodeBNodeBBTSData Collection Module

Real-time information collection

Policy Decision Module

Collaborative energy saving algorithm

is implemented to obtain the optimal

traffic distribution scheme

Terminal

Execution Module

The Base Stations are turned up /off

according to policy decisions

MCES v1.0 at the end of 2015

City Cell Number Progress

Nanning 40000 100%

Shanghai 10000 70%

Suzhou 3000 20%

Yingtan 3000 20%

Beijing 3000 10%

Zibo TBD 10%

Cell number

Total Cell Number

MCES2.0 40746 S-cell Ratio

16.45% S-cell MCES2.0 6704

S-energy Kwh/day

MCES2.0 4880.2

178.13 kwh/year

Deployment in Nanning (2017)

WBD in CMCC 2/3/4G Network

18

18

Endow the RAN with Intelligence

Context and Load Aware

Application Optimization

Macro BS

Pico BS

DU

DU DU

Monitor & Management of

the BS Cooperation Intelligent RAN Resource

Orchestration

Key

Capability User Mobility

Pattern Prediction

Service

Recognition Traffic Load

Prediction

App-Network policy

Mapping Network Portrait

Basic

Capability

Data interface

Standardization Big Data Platform AI Framework GPU/CPU

RDA- RAN Intelligence Engine

RAN data

Collection

Real time RAN

Capability Report

Application

Server

CU/MEC

19

19

Data driven Intelligent RAN Arch (demo @MWC18)

Use Cases of AI in 5G RAN

User mobility & service patterns prediction

Customized

Mobility Management

-110dB-96dB

-98dB

-110dB

Grid-level KPI is good

Grid-level KPI is normal

Grid-level KPI is bad

Signalling event?

drop/HO/re-establish？

YN

Same issue of other users in

the same location?

Y

Coverage

optimiation

N

Specicial UE

related？

Y

UE issue

N

Dev

checking

YN

Bad radio condition？

Simul connected user

number excceed

threshold？Y

Load

balancing

worked？N

Product

issue

Enough data

in buffer？ Y

N

N

Specific app server？

Y

App server

issue

N

Y

Y

Product

issue

N

Dev

checking

Low tput

Scheduling/Power

control issue？

CA CANo-CA CA

Low quality CA Coverage

Area

High quality CA Coverage

Area

CA

Frequency 1

Frequency 2

Coverage and Capacity Optimization

Virtual Grid

Network Energy Saving

QoE issue Debugging

Context Aware Cross Layer Optimization

Context Aware Cross Layer Optimization

Refined user trajectory prediction

Temporal-spatial service feature models

• Power consumption, Resource utilization

•User experience optimization…

Wireless Network User Portraits

20

20

Wireless AI Alliance (WAIA), Aug. 2017

Relying on the cooperation platform of industry-university-research, to realize the

intelligent guidance and in-depth integration of wireless big data, and promote the

development of green, reliable and intelligent communication.

Alliance goals

Organizational Units

Participating Units

BeiHang

University Zhejiang

University

Beijing University of

Posts &

Telecommunications

Cooperative Units

China University of

Science &

Technology

Requirements

WG

Architecture

WG

Tech & Field

Trial WG

Platform

WG

Standards

WG

Working Groups of WAIA

21

21

5G DU

5G CN

AAU/RRU

NMS MANO

Open Interface &

Architecture MEC

RDA (Big Data

Analytics & AI)

5G CU

RAN NFVI

CU-C

NGFI-I

NGFI-II

E2 E1

CU-U

Intelligence &

Standardization

Open Source &

Virtualization

White box

&Reference design

O-RAN: Open & Smart Ecosystem for 5G RAN (Feb 27, 2018, MWC18)

• E2, E3 Interface Standardization

• Open Interface of protocol stack

• Open Capability of Edge Computing

• Open Interface (NGFI-I/NGFI-II)

•Open-source Software,

white-box reference design

CU

DU

AAU/RRU

Intelligent

Management • Big Data-based RRM

• Intelligent computing-based apps

22

22

The Perfect Storm: ICDT True Convergence…

Ai Interface

Signaling/

Control

EE/SE

No more

“Cell”

Spectrum

Fronthaul

Protocol

Stack

Business model Open source NFV/cloud Big data

5G

23

23

Summary

• The UR of 5G: Currently the least resolved issue

• 5G E2E Slicing embracing Verticals

- SDX: SBA(Telecom 4.0, NFV/SDN), UCN/C-RAN, SDAI

• CN: AMF, USDF

• RAN: CU/DU/RRU

• NGFI (xHaul): 1:1 protection, 10ms

• PHY: Coverage (Beam, Repetition, RS Density, Power, SUL), Preemption

• Stack: MAC HARQ, RLC ARQ, PDCP duplication (DC/CA)

• New Frontier: From „Green & Soft‟ to „Open & Smart‟

• No longer “Diversity Coding” era!

• CT, IT (SDN/NFV, OS), DT

• WAIA, O-RAN

24

icl@chinamobile.com

Thank You!