M2M_scheduling_for_LTE

Athanasios Lioumpas

Angeliki Alexiou

Dept. of Digital Systems, University of Piraeus, Greece

December, 2011

Uplink Scheduling for Machine-to-Machine

Communications in LTE-based Cellular Systems

Outline

A Lioumpas and A. Alexiou On the Switching Rate of ST-MIMO Systems with Energy-based Antenna Selection

1. Motivation

2. Solutions

3. Results

4. Conclusions and future work

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Motivation (1/5)


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Research area of this work: LTE scheduling

Motivation (1/5)


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Research area of this work: LTE scheduling OFDMA resource allocation

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Motivation (1/5)


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Research area of this work: LTE scheduling OFDMA resource allocation

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Motivation (2/5)


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LTE uplink and downlink scheduling has been extensively studied towards:• Maximum throughput, • energy efficiency, • fairness, • joint optimization,….

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Motivation (2/5)


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LTE uplink and downlink scheduling has been extensively studied towards:• Maximum throughput, • energy efficiency, • fairness, • joint optimization,….

LTE Quality of Service requirements

3GPP TS 23.203 V10.0.0 (2010-06)

Motivation (3/5)


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3GPP TS 23.203 V10.0.0 (2010-06)

QCI Resourc

e Type

Priority Packet

Delay

Budget

(NOTE

1)

Packet

Error

Loss

Rate

(NOTE 2)

Example Services

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(NOTE 3)

2 100 ms 10-2 Conversational Voice

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(NOTE 3) GBR

4 150 ms 10-3 Conversational Video (Live Streaming)

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(NOTE 3)

3 50 ms 10-3 Real Time Gaming

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(NOTE 3)

5 300 ms 10-6 Non-Conversational Video (Buf fered

Streaming)

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(NOTE 3)

1 100 ms 10-6 IMS Signalling

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(NOTE 4) 6 300 ms 10-6

Video (Buf fered Streaming)

TCP-based (e.g., www, e-mail, chat, f tp, p2p

f ile sharing, progressive video, etc.)

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(NOTE 3)

Non-GBR

7 100 ms 10-3

Voice,

Video (Live Streaming)

Interactive Gaming

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(NOTE 5) 8

300 ms 10-6



f ile

9

(NOTE 6)

9 sharing, progressive video, etc.)

Motivation (3/5)


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3GPP TS 23.203 V10.0.0 (2010-06)

QCI Resourc

e Type

Priority Packet

Delay

Budget

(NOTE

1)

Packet

Error

Loss

Rate

(NOTE 2)

Example Services

1

(NOTE 3)


2

(NOTE 3) GBR


3

(NOTE 3)


4

(NOTE 3)

5 300 ms 10-6 Non-Conversational Video (Buf fered

Streaming)

5

(NOTE 3)


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(NOTE 4) 6 300 ms 10-6



f ile sharing, progressive video, etc.)

7

(NOTE 3)

Non-GBR

7 100 ms 10-3

Voice,


Interactive Gaming

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(NOTE 5) 8

300 ms 10-6



f ile

9

(NOTE 6)


+ CSI for enhancing the scheduler’s performance

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Motivation (3/5)


4/12


3GPP TS 23.203 V10.0.0 (2010-06)

QCI Resourc

e Type

Priority Packet

Delay

Budget

(NOTE

1)

Packet

Error

Loss

Rate

(NOTE 2)

Example Services

1

(NOTE 3)


2

(NOTE 3) GBR


3

(NOTE 3)


4

(NOTE 3)

5 300 ms 10-6 Non-Conversational Video (Buffered

Streaming)

5

(NOTE 3)


6

(NOTE 4) 6 300 ms 10-6

Video (Buffered Streaming)

TCP-based (e.g., www, e-mail, chat, ftp, p2p

file sharing, progressive video, etc.)

7

(NOTE 3)

Non-GBR

7 100 ms 10-3

Voice,


Interactive Gaming

8

(NOTE 5) 8

300 ms 10-6

Video (Buffered Streaming)

TCP-based (e.g., www, e-mail, chat, ftp, p2p

file 9

(NOTE 6)


4 differentdelay requirements

50, 100, 150, 300 ms

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LTE/LTE-MNetwork(s)

IP Network

Base station (eNodeB)

M2M Gateway

Non-LTE-M DevicePDN Gateway

Application Server or Management Platform

Symbols:LTE-M Device

LTE-M InterfaceLTE-M Relay

Non-LTE-M CHNon LTE-M Interface

M2M communications through LTE

Motivation (4/5)


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LTE/LTE-MNetwork(s)

IP Network


M2M Gateway







Vehicle tracking

(real time applications)

Motivation (4/5)


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LTE/LTE-MNetwork(s)

IP Network


M2M Gateway







Monitoring

sensors (delay tolerant)

Motivation (4/5)


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LTE/LTE-MNetwork(s)

IP Network


M2M Gateway







E-health care devices

(delay tolerance depending on patient conditions)

Motivation (4/5)


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M2M applications Challenges:

vast diversity of applications + huge volume of machines

create a totally different landscape

Delay tolerance may vary

from a few msec to several

hours/days/months

Motivation (5/5)


LTE: 4 differentdelay requirements

50, 100, 150, 300 ms

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State of the art

Downlink and Uplink scheduling for LTE servicesextensively studied

Solutions(1/3)


First approach by [Lien et al. IEEE Com. Mag. 11]

M2M scheduling in LTE-based cellular sytems: the literature is very limited

M2M devices grouped according to their delay/traffic class

Our contribution:1. Show that LTE delay-tolerant classes are insufficient for M2M

communications2. The knowledge of the exact delay tolerance of each device SIGNIFICANTLY

affects the number of served devices2. Two scheduling algorithms for M2M in LTE-based cellular systems

• Channel + delay tolerance aware scheduler

Gives priority to throughput maximization• Energy efficient. Sleep mode according to their delay tolerance

• Channel + delay tolerance aware scheduler

Gives priority to delay sensitive applications

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Solutions(2/3)


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Solutions(3/3)


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Results(1/2)


With Algorithm 1 the number

of satisfied devices increases

up to 10% compared to the the

channel only aware

schedule

Algorithm 1 achieves higher

BER compared to the channel

only aware schedule, it also

depends on the devices’ delay

tolerance.

Conclusion: There is a

trade-off between BER and

number of satisfied users

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Results(2/2)


Knowing the exact delay

tolerance of each device

(Algorithm 1) leads to

significant increase in the

number of satisfied devices.

Algorithm 2 achieves similar

BER compared to the 5-delay

classes scheduler.

Conclusion: The knowledge

of the exact delay tolerance

of each device

SIGNIFICANTLY affects the

number of served devices

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Conclusions and future work


Future work

– Impact of the delay tolerance knowledge on the system‘s capacity (theoretical analysis)

– New LTE delay tolerance classes (trade-off between number of served devices and feedback bandwidth)

• LTE is not ready for supporting a large diversity of services with different

delay requirements

• The LTE current classes ARE NOT sufficient (50, 60, 150 1nd 300 msec)

•The knowledge of the exact delay tolerance of each device

SIGNIFICANTLY affects the number of served devices

Thank you!

Acknowledgements:

This work has been performed in the framework of the ICT project ICT-

5-258512 EXALTED, which is partly funded by the European Union. The

authors would like to acknowledge the contributions of their colleagues. This

information reflects the consortiums view, the Community is not liable forany use that may be made of any of the information contained therein.

http://www.ict-exalted.eu/


Technology

M2M_scheduling_for_LTE