CMU-GM Collaborative Research Lab

Rahul Mangharam, D. Weller, D. Stancil, Raj Rajkumarrahul@cmu.edu

Carnegie Mellon University

Jay Parikh, General MotorsACM VANET, Cologne, Germany. 2 September 2005

Geographic Routing For Multi-hop Wireless Vehicular Networks

CMU-GM Collaborative Research Lab

Experimental Multi-hop Vehicular Network Test-bed

Mobile Nodes

GPS

Differential GPS reference station beacons

1. Vehicle-to-Vehicle Multi-hop

2. Vehicle-to-Mobile Gateway

3. Vehicle-to-Infrastructure

5.9 GHz DSRC Dedicated Short Range Communications Between vehicles

1XRTT Cellular Data Network

Internet

Remote Monitoring of Experiment

CMU-GM Collaborative Research Lab

Vehicular Networking Application Categories

1. Safety Alerts– Sudden Breaking– Airbag deployment– Skidding

2. Traffic Congestion Probing– Travel Time– Dynamic Route Planning– Road Condition Notification

3. Interactive Applications– Social Networking– Multimedia Content Exchange– Advertising

CMU-GM Collaborative Research Lab

GrooveNet Test Kit

5.8 GHz ANTENNAS

GPS ANTENNA

LAPTOP w/ RADIO CARD

HEADPHONES W/ MICROPHONE

GPS RECEIVER

POWER CORD (12 DC)

WEB CAM

• Driven 5 vehicles over 400 miles – Urban, Rural and Highway• Over 625,000 link measurements

CMU-GM Collaborative Research Lab

Broadcast Scenarios

Highway Driving City Driving Rural Driving

• Path with Intermediate points• Static Source Routing

• Radial Broadcast • Bounding Box• Controlled Flooding

CMU-GM Collaborative Research Lab

GrooveSim: Hybrid Simulator for Vehicular Networks

1. Drive: On-road communication, tracking, logging• Over 400 miles driven with 5 vehicles

• Test Robustness of Protocol

2. Simulate: Over 5,000 concurrent vehicles Anywhere in the US• Scalability & Performance Analysis over City, Rural, Highway

3. Playback: Visual Performance Analysis• Networking, Propagation, GPS Performance

4. Hybrid Simulate: Mix Real & Virtual Vehicles• Effect of real Traffic and Channel

5. Test Generation: Easy Large-scale test setup

Five Modes of Operation

CMU-GM Collaborative Research Lab

Vehicular Network Modeling

• Mobility Model– Speed: Uniform, Street Speed, Markov Model, Load-based model

• Trip Model– Random walk, Explicit Origin-Destination, Distributed Origin-Dest

• Communication Model– Channel Model and Multiple Access Model

• Traffic Model– Start time distribution, use real or synthetic traces

CMU-GM Collaborative Research Lab

Degrees of Freedom & Metrics

• Degrees of Freedom1. Start time2. Speed3. Vehicle density4. Travel direction5. Size of routing region6. Message rebroadcast frequency7. Transmission power

• Performance Metrics1. Message Penetration Distance2. Message Delay3. Message Lifetime

CMU-GM Collaborative Research Lab

Minimum Weight Routing

1,000 Vehicles in Chicago, IL suburbRouted with Minimum Cost Routing

CMU-GM Collaborative Research Lab

Minimum Weight Routing (2)

Vehicles migrate to roads with higher speed limits

CMU-GM Collaborative Research Lab

Message Penetration vs. Travel Distance

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0 2 4 6 8 10 12 14 16 18 20Travel Distance (Km)

Mes

sage

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etra

tion

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tanc

e (m

)

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Variation of Group Size with Travel Distance

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up S

ize

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f veh

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s)

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Performance: Message Propagation Distance

CMU-GM Collaborative Research Lab

Street Intersection Message Lifetime

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0 100 200 300 400 500 600Bounding Circle Radius (m)

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sag

e L

ifet

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Performance: Message Lifetime

CMU-GM Collaborative Research Lab

Bounding Box Size

# Active Vehicles

Message Delay (sec)

0 1 192

1 138 40.4

2 150 19

3 162 11

Performance: Message Delay

CMU-GM Collaborative Research Lab

CMU-GM Collaborative Research Lab

GrooveSim is Easy to Use