V2V Communication for Safety, Information and Entertainment

1. V2V Communication for Safety, Information and Entertainment J. Parikh General Motors R&D Nov. 14, 2006

2. Content • Introduction and Background • DSRC Wireless Communication • Safety, Information and Entertainment Applications • Technical Challenges • Current and Future Research Work

3. Introduction

4. What are wireless systems? • Wireless systems encompass those technologies that enable communications of voice or data without a direct-wired connection. • These currently employ much of the electromagnetic spectrum from very low radio frequencies (tens of kHz) through visible light (1012 kHz).

5. Communication on Road…

6. Bluetooth 802.11 802.15.3 Today’s Vehicles - Wireless Data Interfaces Terrestrial Broadcast Digital Radio Satellite A/V GPS DSRC PCS/ Cellular 802.11 WLAN Ad Hoc Networks 802.15.3 WPAN

7. Central Control Center Transit Dynamic Signal Control DSRC and Other Communications En-Route Traffic Advisory and Assistance 911 and Other Call Center Trip Planning Commercial Vehicle Operation Traveler Assistance VARIABLE MESSAGE SIGNS Integrated Traffic Management Systems

8. DSRC – Wireless Communication

9. Dedicated Short Range Communication “… a short to medium range (1000 meters) communications service that supports both public safety and private operations in vehicle-to-vehicle and vehicle-to-roadside communication environments by providing very high data transfer rates where minimizing latency in the communication link and isolating relatively small communication zones is important.”

10. 915 MHz Range < 30 meters Data rate = 0.5 mbps Designed for ETC, but can be used for other applications Single unlicensed channel Requires special (custom) chip set & software Vehicle to Infrastructure Command-response Don’t Confuse With Existing DSRC 5.9 GHz • Range to 1000 meters • Data rate 6 to 27 mbps • Designed for general internet access, can be used for ETC • 7 licensed channels • Uses open off-the-shelf chip set & software • V2V and V2I • Command-response & peer to peer • Based on IEEE 802.11a • High speed impacts physical layer • Very latency (<50ms) – MAC impact • Random MAC addresses for privacy • IPv6 for network layer • Support for in-car networks

11. Standards Program

12. 5.9 GHz Channel Plan Shared Public Safety/Private Dedicated Public Safety Med Rng Service Hi Av-Low Lat Intersections Short Rng Service Control Power Limit 43 dBm 40 dBm Power Limit 33 dBm Power Limit 23 dBm Uplink Downlink Public Safety Veh-Veh Public Safety/ Private Public Safety/ Private Public Safety/ Private Public Safety/ Private Public Safety Intersections Control Channel Ch 180 Ch 182 Ch 172 Ch 184 Ch 178 Ch 174 Ch 176 5.925 5.875 5.880 5.905 5.910 5.850 5.855 5.860 5.865 5.870 5.885 5.890 5.895 5.900 5.920 5.825 5.845 5.835 5.830 5.915 5.840 Frequency (GHz) Canadian Special License Zones*

13. – DSRC Applications – Safety, Information & Entertainment

14. Classes of Application • Active Safety – Actively monitors the environment around the vehicle in order to warn • Driver Assistance – Assists drivers in the operation of the vehicle either by relieving them of certain driving tasks or by providing them with useful information about the surrounding environment. • Traffic Efficiency – Provides information to the managers of the roadway infrastructure to enable more efficient control and maintenance of the roadways. • Infotainment/Commercial – Provides drivers with various types of communication services in order to improve driver productivity, entertainment, and convenience.

15. Safety Application Areas

16. Incidence notification to OnStar • Information relay to other vehicles for dynamic route guidance Example Traffic Scenario – Safety Application • Immediate spread of knowledge to surrounding vehicles within broadcast range Exit

17. V2V/V2I Safety Application

18. Form small clusters of vehicles • Aggregate data within cluster • Transmit aggregated values GPS Report GPS Time Speed Lon, Lat Heading Report GPS Time Speed Lon, Lat Heading Report GPS Time Speed Lon, Lat Heading Report GPS Time Speed Lon, Lat Heading Report GPS Time Speed Lon, Lat Heading Report GPS Time Speed Lon, Lat Heading Report GPS Time Speed Lon, Lat Heading Traffic Probe - Information Vehicles report speed, position and heading

19. Roadcasting - Entertainment A prototype system that allows anyone to have their own radio station, broadcasted among wirelessly capable cars (devices) of an ad-hoc wireless network. The system can become aware of individual preferences and is able to choose songs and podcasts that people want to hear, on their own devices and car stereos. Visit http:roadcasting.org to learn more…

20. Application Categories

21. Technical Challenges

22. Ad hoc Routing Protocols Hybrid Reactive/On-Demand Proactive/Table Driven ZRP/GRID/LAR DSDV OLSR CGSR STAR ABR DSR TORA AODV RDMAR CBRP “Ad hoc” Routing Protocols • Proactive, Reactive, Hybrid • Goal: Find a node given a logical address based on a flat addressing hierarchy • Method of Operation: Flooding • Mechanism: Handshaking - Route request, route reply, route maintenance and route erasure

23. Ad hoc Routing Protocols – Quick Overview • AODVAd hoc On-demand Distance Vector • Reactive • Forwarding addresses stored in routers • Lightweight and flexible • DSRDynamic Source Routing • Reactive • Packet header contains route • Independent of router state • OLSROptimized Link State Routing • Proactive • Similar to link state routing with clusters • Bounded routing overhead • GRID Geographic Routing Protocol • Controlled flooding based on geographic coordinates • Requires location service

24. 11 retransmission to diffuse a message up to 3 hops 24 retransmissions to diffuse a message up to 3 hops Retransmission node Retransmission node OLSR: Reduced Flooding Through Hierarchy

25. Key Issues with Ad hoc Protocols • Scalability – Flooding generates LOT of traffic • Optimizations have limited impact: • Use Route Caching (beware of stale routes) • Use Node Hierarchy (longer setup duration) • Link Oscillation – Channel variations cause pathological rerouting • Damp rerouting requests – when a “better” path is available • Use Signal Stability Routing Metric • Route repair with controlled flooding – hop-count based on previous route length • End-to-end Route Repair – Causes lot of overhead • Use local repair • Link Quality –Shortest path often performs poorly • Use combined routing metric (hop count, stability, load)

26. Research Work

27. Vehicle Networks: Unique Applications • Safety Messages– Critical Broadcasts • Low latency • Send Locally • Non-critical Traffic Updates • Send to targeted groups (location, speed, neighborhood, id) • Maintain connectivity map • Telematics Applications • Provide QoS Support • “Suspend & Resume” applications and routes

28. Vehicle Networks: Unique Challenges • Network Density - Large Dynamic Range • Same protocol must work in bumper-to-bumper downtown traffic and on interstates • Mobility Patterns and Varying Vehicle Speeds • Cars entering or exiting highways need complete route updates and can possibly pollute new neighbors during transitions • Traffic moves in parallel and at different speeds – difficult to form clusters or handshake • Heterogeneous Nodes • Connectivity: Support DSRC and Cellular • Positioning Capability: GPS and no-GPS • Application Support: Full-function and Reduced-function devices • Information is Geographic Route and Direction Specific • Need to map geographic routes to logical routes • Getting direction info is not too reliable

29. Vehicle Networks: Unique Degrees of Freedom • Protocol Operation Modes • Time of Day: “Rush Hour – Set cluster size to 3-hops” • Traffic Characteristic: “Highway Driving – Switch to Cluster-based Routing Mode” • Traffic Database Update: “Traffic Probe: Congestion ahead – Routing Table Burst Update” • Routing Metrics (a) Hop count (b) SNR (c) Signal Stability (d) Connectivity (e) Link load (f) Multiple Paths

30. Internet 1xRTT Cellular Data Network Remote Monitoring of Experiment Experimental Multi-hop Vehicular Network Test-bed 5.9 GHz DSRC Dedicated Short Range Communications Between vehicles GPS Differential GPS reference station beacons Mobile Nodes • Vehicle-to-Vehicle Multi-hop • Vehicle-to-Mobile Gateway • Vehicle-to-Infrastructure

31. Vehicular Networking Application Categories • Safety Alerts • Sudden Braking • Airbag deployment • Skidding • Traffic Congestion Probing • Travel Time • Dynamic Route Planning • Road Condition Notification • Interactive Applications • Social Networking • Multimedia Content Exchange • Advertising

32. GeoRoute: Broadcast Scenarios Highway Driving City Driving Rural Driving • Path with Intermediate points • Static Source Routing • Radial Broadcast • Bounding Box • Controlled Flooding

33. Conclusion • Communicating vehicles and infrastructure will bring cost effective, large scale gains in safety, traffic management and convenience. • DSRC (IEEE 802.11p) is the enabling technology for making this vision into reality. • Number of technical challenges remain, but can and will be solved with government, industry and academic research partners. • VII (Vehicle Infrastructure Integration) will provide the necessary business and deployment framework over the next few years. • There are many exciting opportunities for other industry participants to make contributions and to benefit from a DSRC/WAVE and VII deployment.

34. Questions ???