Dedicated Short Range Communications

Basic Description

Dedicated Short Range Communications (DSRC) is a data-only automotive communication protocol. Their are two broad categories of DSRC: Vehicle to Vehicle (V2V) communication and the Vehicle to Roadside (V2R) communication. Typical or potential applications of DSRC include:

• Electronic toll collection
• Cooperative adaptive cruise control
• Intersection collision avoidance
• Approaching emergency vehicle warning
• Automatic vehicle safety inspection
• Transit or emergency vehicle signal priority
• Electronic parking payments
• Commercial vehicle clearance
• In-vehicle display of road signs and billboards
• Traffic data collection
• Rail intersection warning

DSRC is widely used for electronic toll collection (a V2R application) today. V2V applications will not be fully functional until a significant percentage of cars on the road are equipped with DSRC systems.

Forward Obstacle Detection and Avoidance: In this application DSRC channel is used to communicate traffic information or accident warnings back through vehicles to caution the drivers of a possible danger ahead. Communication with vehicles directly behind or in front of an automobile can be used to enhance the functionality of adaptive cruise control systems. Information passed from vehicle to vehicle can warn the driver of obstacles or road hazards thousands of feet ahead.

Approaching Emergency Vehicle Warning: Vehicle to vehicle DSRC would enable information about an approaching emergency vehicle to be relayed from vehicle to vehicle forward through traffic. This would help to clear the way for the emergency vehicle and reduce the risk to other vehicles.

DSRC for electronic toll collection is primarily done at 915 MHz in the U.S. However, the FCC has allocated 75 MHz of bandwidth at 5.9 GHz for DSRC communications. In Europe 30 MHz of bandwidth at 5.9 GHz has been allocated for this purpose, while in Japan the allocated frequency is 5.8 GHz. At 5.8 - 5.9 GHz, communication at data rates of 6 to 27 Mbps can occur at distances of several hundred meters.

While V2V DSRC systems are still in their infancy, much is being done to develop them. In Europe in particular there are collaborative research projects to further develop every level of the system from in-car hardware and software to infrastructure. Many of the large automakers of the world are also developing DSRC systems including: BMW, Daimler, GM, Honda, Mercedes, Nissan, Toyota, Volvo, and Volkswagen.

Manufacturers

ARINC, Cohda wireless, Mitsubishi Electric

For More Information

[1] TMC Develops Onboard DSRC Unit to Improve Traffic Safety - Toyota Press Release, Sep. 3, 2009.

[2] Dedicated Short Range Communications (DSRC) Home - Armstrong Consulting web site.

[3] Dedicated Short-Range Communications - Wikipedia.

[4] Dedicated Short Range Communications (DSRC) Service, FCC DSRC page.

[5] Automotive RFID Gets Rolling, Jonathan Collins, RFID Journal, Apr. 13, 2004.