potential of lte for machine-to-machine communication · · 2013-10-22›currently maximum drx...

Potential of LTE for Machine-to-Machine Communication

Dr. Joachim Sachs

Ericsson Research

Joachim Sachs | ITG Zukunft der Netze 2013, 2013-09-20 | © Ericsson AB 2013 | 2013-09-20 |

Outline

› Trend towards M2M communication

› What is the role of cellular communication

› Cellular M2M Communication

– Focus: battery-efficient LTE for sensors and meters

› Conclusion


1875 1900 1925 1950 1975 2000 2025

~0.5 B PLACES

Global

Connectivity

Source: Ericsson

Telecommunication today


1875 1900 1925 1950 1975 2000 2025

~0.5 B PLACES

Global

Connectivity

Personal

Mobile

Source: Ericsson

5.0 B PEOPLE

Telecommunication today

Inflection

point


1875 1900 1925 1950 1975 2000 2025

50 B

5.0 B

~0.5 B PLACES

PEOPLE

THINGS

Inflection

points

Global

Connectivity

Personal

Mobile

Networked

Society

Source: Ericsson

Telecommunication tomorrow


1875 1900 1925 1950 1975 2000 2025

50 B

5.0 B

~0.5 B PLACES

PEOPLE

THINGS

Source: Ericsson

The Networked Society

Machine-to-machine communication will

spread into all facets of our increasingly

digitized society: businesses and

industries, public sectors and private lives

“everything that benefits

from being connected will

be connected”


Role of cellular communication ? (1)

› Capabilities to fulfill demanding requirements, not limited to personal

communication

› 5G research is starting up (e.g. in EU METIS project)

– including an M2M focus on low delay, massive scalability, low energy, high reliability

GPRS

1998

WCDMA

2002

HSPA

2005

HSPA +

2009

LTE

2010

LTE-A

2014

PEAK RATE

40 Kbps 384 Kbps

300 Mbps

42 Mbps14 Mbps

>1 Gbps

The extremely high throughput of LTE

enables new possibilities for M2M

applications.

2G 3G 4G

GPRS

Rel 97

EDGE

Rel 99

EDGE

Rel 4

WCDMA

Rel’99

Evolved

EDGE

HSDPA HSPA LTE

700

La

ten

cy (

ms

)

10 ms

RAN RTT

600

500

400

300

100

200

The extremely low latency of LTE

enables new possibilities for M2M

applications.

LATENCY


Role of cellular communication ? (2)

› Almost ubiquitous availability of connectivity

[Source: Ericsson Mobility Report, June 2013]

› Low costs for introducing new

communication services

› Economies of scale

› Global markets and solutions

› Future proof


M2M areas with diverse requirements

› Sensor, actuators, meters,

connected devices and things

› Small, simple, low-cost

› Low energy consumption

› Long-range coverage

› Distributed embedded control &

cyber-physical systems

› High reliability and availability

› Low delay

› Autonomous operation

Healthcare Building

automation Utilities

Transport &

Logistics Utilities

Industrial

automation

Security &

Safety Government

Meters and Sensors Critical Communication

› Connecting vehicles, transport infrastructure and

transport management

› Incl. safety-related services

› Low delay

› High mobility

Transport & Logistics

Intelligent Transport Systems


M2M areas with diverse requirements

› Sensor, actuators, meters,

connected devices and things

› Small, simple, low-cost

› Low energy consumption

› Long-range coverage

› Distributed embedded control &

cyber-physical systems

› High reliability and availability

› Low delay

› Autonomous operation

Healthcare Building

automation Utilities

Transport &

Logistics Utilities

Industrial

automation

Security &

Safety Government

Meters and Sensors Critical Communication

› Connecting vehicles, transport infrastructure and

transport management

› Incl. safety-related services

› Low delay

› High mobility

Transport & Logistics

Intelligent Transport Systems

ITG Zukunft der Netze, 2011

“Automotive Communication via

Mobile Broadband Networks”

Addressed in

5G project METIS

Focus of M2M-related

activities in 3GPP


Sensors & Meters Use cases

› Building automation (temperature, light, doors, heating, …)

› Ambient Assisted Living personal monitor (blood pressure, pulse, …)

› Sensors and smart meters in the smart grid (e.g. distributed weather sensors)

› Goods / fleet tracking in logistics

› Agriculture / aquaculture sensors (irrigation, fertilization, cattle tracking, …)

› Smart city infrastructure monitoring (availability of parking lots, full dustbins, …)


Sensors & Meters Characteristics

› Typically infrequent measurements of limited size

› Traffic mainly in uplink (measurement reports),

but downlink also possible (configuration, SW update, control)

› Delay-tolerant in downlink and / or uplink

› Stationary or mobile devices

› Long lasting battery operation or with power supply

› Constrained (cost/processing) or complex devices

› Potentially dense accumulation of many devices


Sensors & Meters Characteristics

› Typically infrequent measurements of limited size

› Traffic mainly in uplink (measurement reports),

but downlink also possible (configuration, SW update, control)

› Delay-tolerant in downlink and / or uplink

› Stationary or mobile devices

› Long lasting battery operation or with power supply

› Constrained (cost/processing) or complex devices

› Potentially dense accumulation of many devices

Theme


Suitability of LTE for sensors & meters (LTE Release 8) (1)

› Are LTE devices simple ? (with regard to the defined M2M requirements)

– High requirements on M2M device

– Cost reduction of up to 80% possible

(3GPP TR 36.888) by reduced UE features

and performance

– 3GPP Rel-12 work item targeting 50% cost reduction

› 1 receive antenna

› Data rates limited to 1 Mb/s

› Data transmission in 1.4 MHz only

Low-end UE category 1

› Downlink

– up to 10 Mb/s (64 QAM)

– up to 10296 bits transport block size

– 2 receiver antennas and

reception from up to 4 antenna ports

– single stream transmission

› Uplink

– up to 5 Mb/s (16 QAM)

– up to 5160 bits transport block size

– two transmit antennas

› Layer 2 buffer size 150 kB

Source: 3GPP TS 36.306 and Dahlman et al. 2011



› Are LTE devices well reachable ?

– MTC devices may have unfavorable attenuation

› Basement of buildings

› Foil-insulated enclosures

– Stationary MTC devices in particular affected

– 3GPP TR 36.888 lists coverage improvement options for low-rate MTC devices

› Repetition with energy accumulation

› Power boosting

› Relaxed performance requirements

› Design of new channels / signals

– 3GPP Rel-12 work item targeting 15dB coverage extensions for MTC UEs



› Can LTE handle effectively huge number of M2M devices ? (with regard to the defined M2M requirements)

– Maybe not in extreme situations?

– Protection in 3GPP Rel-11

“Enhanced Access Barring”



› Does LTE enable M2M devices to operate on battery for multiple years? (with regard to the defined M2M requirements)

– Not really

› Efficient LTE transmission of infrequent small data ? (with regard to the defined M2M requirements)

– Quite some signaling involved


Low-energy transmission for MTC UEs (1)

› What is consuming most device energy for infrequent small data transmission?

active

time UL

DL

inactive active

pow

er

consum

ption

data signaling



active

time UL

DL

inactive active

data signaling paging / measurements DRX / paging

cycle

pow

er

consum

ption




active

time UL

DL

inactive active

data signaling paging / measurements DRX / paging

cycle

pow

er

consum

ption

DRX active times dominate UE energy consumption


Joachim Sachs | ITG Zukunft der Netze 2013, 2013-09-20 | © Ericsson AB 2013 | 2013-09-20 | Page 22

› Currently maximum DRX (&paging) cycles of 2.56 s

› Longer DRX can reduce UE energy consumption

› Energy saving vs. delay trade-off for downlink data – Long DRX cycle reduce the UE responsiveness to network triggers

e.g. with 2.56 s DRX cycle a UE can respond on average within 1.28 s

– If UE is delay tolerant for downlink data, long DRX cycles can be used

› In uplink a UE can transmit whenever it desires – no delay impact



› Assumptions

– No downlink transmission

– Uplink transmission

› 1000 bytes every 12 min.

› 10 ms synchronisation

› 50 ms data transmission

– DRX active periods


› 10 ms reading control channel



0 50 100 150 200 250 300 350 4000

5

10

15

20

25

DRX cycle length (s)

Batt

ery

lifetim

e f

acto

r

Energy consumption

0 50 100 150 200 250 300 350 4000

0.2

0.4

0.6

0.8

1

Energ

y c

onsum

ption (

rela

tive)

Battery lifetime

Energy consumption


AAA battery 6.5 kJ

DRX 384 s

Battery life 67.2 months

Avg. DL response ~3 min

DRX 2.56 s

Battery life 2.8 months

Avg. DL response 1.28 s

› Assumptions

– No downlink transmission

– Uplink transmission

› 1000 bytes every 12 min.


› 50 ms data transmission

– DRX active periods


› 10 ms reading control channel

Source: Tirronen et al. 2012 & 2013


Optimized transmission for small data (1)

› Can we simplify the transmission procedures for small data transmission?

– Connection / bearer setup and

tear-down for every data transfer

Connection and security setup

Connection release

server

small data



› Investigation on optimizations is currently ongoing in 3GPP

– E.g. keep UE in RRC_CONNECTED

state with long sleep (DRX) cycles

– E.g. simplified bearer handling and

lightweight connection setup

keep UE RRC_CONNECTED

keep UE RRC_CONNECTED



› can prolong the battery

life time by up to 36 %


Summary

› Machine-to-machine communication is a major new trend in wireless

communication

› Cellular communication will play a strong role

(capabilities, availability, global market)

› Optimization of cellular communication is possible for M2M

– Consider new system requirements

› 3GPP work is ongoing for

– Reduced UE modem costs (for simple M2M devices)

– Battery saving and signaling reductions

for infrequent transmission of small data transmissions


References

› J. Sachs, A. Wallen, “Machine-to-machine communication with LTE ”, tutorial, IEEE Communication Theory Workshop

Sweden, Oct. 2012.

› T. Tirronen, A. Larmo, J. Sachs, B. Lindoff, N. Wiberg, “Machine-to-machine communication with long-term evolution

with reduced device energy consumption”, Trans Emerging Tel Tech, 2013

› Erik Dahlman, Stefan Parkvall, Johan Sköld, ”4G LTE/LTE-Advanced for Mobile Broadband,” Academic Press, 2011

› T. Tirronen, A. Larmo, J. Sachs, B. Lindoff, N. Wiberg, ”Reducing energy consumption of LTE devices for machine-to-machine communication,” IEEE Globecom 2012

› D. Astely, E. Dahlman, G. Fodor, S. Parkvall, J. Sachs, “LTE Release 12 and Beyond,” IEEE Communications Magazine, July 2013

› J. Sachs, “Automotive Communication via Mobile Broadband Networks”, ITG Zukunft der Netze, 2011.

› M. Phan, R. Rembarz, S. Sories: 'A Capacity Analysis for the Transmission of Event and Cooperative Awareness Messages in LTE Networks', ITS World Congress 2011, Orlando, Florida, October 2011

› 3GPP TR 36.888, “Study on provision of low-cost Machine-Type Communications (MTC) User Equipments (UEs) based

on LTE”

› 3GPP Rel-12 Work Item, ”Low cost & enhanced coverage MTC UE for LTE”, http://www.3gpp.org/ftp/tsg_ran/TSG_RAN/TSGR_60/Docs/RP-130848.zip

› 3GPP TR 23.887, “Architectural Enhancements for Machine Type and other mobile data applications Communications”

http://www.3gpp.org/ftp/tsg_ran/TSG_RAN/TSGR_60/Docs/RP-130848.zip





potential of lte for machine-to-machine communication · · 2013-10-22›currently maximum drx...

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