Peiyuan Lai, Xinhong Wang, Ning Lu, Fuqiang Liu

Broadband Wireless Communication and Multimedia Laboratory, Tongji University, Shanghai, China

IEEE Intelligent Vehicles Symposium(IVS), 2009

112/04/20I-Hsin Liu

IntroductionRB-MP Protocol SimulationConclusion

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Vehicular Ad hoc NETworks (VANETs) are expected to support some applications. ◦traffic alert dissemination◦file sharing

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Analyzes of traditional routing protocols for Mobile Ad hoc NETworks (MANETs) demonstrated that their performance is poor in VANETs.

The main problem with these protocols in VANETs environments is their route instability.

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The traditional route is established a fixed succession of nodes between the source and destination.◦the routes leads to frequent broken routes in

the presence of VANETs’ high mobility.

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Many packets are dropped.The overhead due to route repairs or

failure notifications increases.◦low delivery ratios◦high transmission delays

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Proposed a reliable broadcast routing scheme based on mobility prediction (RB-MP) to achieve an efficient multi-hop broadcast.

This scheme selects the reliable and efficient rebroadcast nodes, according to the prediction holding time provided by position and relative velocity.

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To make the broadcast communication as reliable as possible.

To enhance bandwidth efficiency.

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Each vehicles equipped with a GPS and a wireless communication device.

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Nodei

Nodej

R

<ID, previousPosition, currentPosition,Speed>

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Previous position

Current position

D0

D

Nodej

Nodei

R

12

Previous position

Current position

D0

D

Nodej

Nodei

R

13

Previous position

Current position

D0

D

Nodej

Nodei

return 1, if D-D0>0return -1, if D-D0<0

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A BC

D

A

ID Neighbor Info. Group

B <speed, prePosition, curPosition, Speed>

<1,0,0>

C <speed, prePosition, curPosition, Speed>

<0,1,0>

D <speed, prePosition, curPosition, Speed>

<0,0,1>

E <speed, prePosition, curPosition, Speed>

<0,0,1>E

return 1, if D-D0>0return -1, if D-D0<0

If PHT-PUP(position updating period) > 0Select the biggest PHT to rebrodcast.Else select the fastest node to rebrodcast.

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In this paper, we have presented a new efficient multi-hop broadcast scheme RB-MP for VANET.

In particular, it is showed that RB-MP is more reliable and efficient than UMB in high mobility situation.

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Thank You