WTE-MAC Wakeup Time Estimation MAC For Improving End-to-End Delay Performance In

WSN

Jae-Ho Lee, Kyeong Hur

and Doo-Seop Eom

MILCOM, 2011

Outline

• Introductions• Related Works• Goals• WTE-MAC• Evaluations• Conclusions

Introductions

Introductions

• Duty Cycle

A

B

Wake up Sleep

Wake up Sleep Sleep

Wake up

Introductions

• Duty Cycle– synchronous

A

B

Wake up Sleep

Wake up Sleep Sleep

Wake up

SYNC

Sleep Wake up

Introductions

• Duty Cycle– asynchronous

A

B

Wake up Sleep

Wake up Sleep Sleep

Wake up

Idle listening

Related Works

• B-MAC

A

B

Wake up Sleep

Wake up Sleep Sleep

Wake up

Joseph Polastre, Jason Hill, and David Culler. Versatile Low PowerMedia Access for Wireless Sensor Networks. In Proceedings of theSecond International Conference On Embedded Networked SensorSystems (SenSys 2004), pp. 95–107, November. 2004.

preamble

ACK

DATA

Related Works

• X-MAC

A

B

Wake up Sleep

Wake up Sleep Sleep

Wake up

Michael Buettner, Gary V. Yee, Eric Anderson, and Richard Han. XMAC:A Short Preamble MAC Protocol for Duty-Cycled WirelessSensor Networks. In Proceedings of the 4th International Conference onEmbedded Networked Sensor Systems (SenSys2006), pp. 307–320, 2006.

P

ACK

DATAP P P

Goal

• Improve end-to-end delay in multi-hop topologies with low power consumption

WTE-MAC

• SND: Synchronization at the Neighbor's Duty cycle• Virtual Tunnel Construction• Expanding SND into the multi-hop Environment

WTE-MAC

• SND: Synchronization at the Neighbor's Duty cycle• Virtual Tunnel Construction• Expanding SND into the multi-hop Environment

WTE-MAC

A

B

Sleep

Wake up Sleep Sleep

Wake up

P

ACK

DATAP P P

Sleep

Wake up

Wake up

Retransmission Interval (RI)

Retransmission Count (RC)

Duty cycle Duration (DD)

RC = 1 2 3 4

RI

Neighbor table

B Info.

.

...

R X

receive

Wake up time

Duty cycle period (DD)

, 1 , _( ( 1) )wakeup n recv n RI duty cycleE T RC T T

Early wakeup

P

ACK

Ewakeup,n+1

WTE-MAC

• SND: Synchronization at the Neighbor's Duty cycle• Virtual Tunnel Construction• Expanding SND into the multi-hop Environment

WTE-MAC

Event(infrequent/bursty)

Forward data

FT : Fixing topology

F

E D

C

B

A

Virtual Tunnel

WTE-MAC

Event(infrequent/bursty)

Forward data

FT : Fixing topology

F

E D

C

B

A

Virtual Tunnel

WTE-MAC

• SND: Synchronization at the Neighbor's Duty cycle• Virtual Tunnel Construction• Expanding SND into the multi-hop Environment

WTE-MACA

B

Wake up Sleep

Wake up Sleep Sleep

Wake up

P

A

P PC

Wake up Sleep

P P

RC = 1 2 3

4 5

A

Sleep

CBA

Wake up

Wake up

Wake up

P

1

A P

1

A

Virtual Tunnel

Sleep

Sleep

SleepEnd-to-End Delay

without SNDEnd-to-End Delay

after SND

RI

Ewakeup,n+1

WTE-MACA

B

Wake up Sleep

Wake up Sleep Sleep

Wake up

P

A

P PC

Wake up Sleep

P P

1 2 3

4 5

A

Sleep

CBA

Wake up

Wake up

Wake up

Virtual Tunnel

Sleep

Sleep

Sleep

RI

Sleep

Sleep Wake up

Wake up

Sleep

Sleep

Dack Dack Dack

, 1 , _( 1) ( 1)wakeup n recv n RI duty cycle ackE T RC T T N D

Evaluation

Parameter Value

Duty Cycle period 1 second

RF Tx Rate 250kbps

Traffic Source VBR 100kbps

Average Packet Length 128Bytes

Initial Wakeup Time Rate 10% / Duty Cycle

Routing Algorithm AODV , Flooding

Power in state(Sleep/Wakeup) 0.4 / 8.7 (μA)

Power in mode(Tx/Rx) 28.9 / 15.2 (mA)

Communication Range 200 meter

CCA Effective Range 280 meter

Interference Range 680 meter

Default Simulation time 100,000 second

Evaluation

Evaluation

Evaluation

Evaluation

Evaluation

Evaluation

Evaluation

Conclusions

• The SND mechanism that is designed to reduce the delivery delay per link• The Virtual Tunnel that is created by expanding the SND into the multi-

hop can provide an enhanced performance of end-to-end delivery delay• It is energy efficient by decreasing unnecessary retransmissions.