Vehicular Communication Systems are an emerging type of networks in which vehicles and roadside units are the communicating nodes, providing each other with information, such as safety warnings and traffic information. As a cooperative approach, vehicular communication systems can be more effective in avoiding accidents and traffic congestions than if each vehicle tries to solve these problems individually. Vehicular communications is mainly motivated by the desire to implement Intelligent Transport Systems (ITS) because of their key benefits in safety and traveling ease.

Generally vehicular networks are considered to contain two types of nodes, vehicles and roadside stations. Both are Dedicated Short Range Communications (DSRC) devices. DSRC works in 5.9 GHz band with bandwidth of 75 MHz and approximate range of 1000m. The network should support both private data communications and public (mainly safety) communications but higher priority is given to public communications. Vehicular communications is usually developed as a part of Intelligent Transport Systems (ITS). ITS seeks to achieve safety and productivity through intelligent transportation which integrates communication between mobile and fixed nodes. To this end ITS heavily relies on wired and wireless communications.

Vehicular Communication Systems are also called as V2V (short for vehicle to vehicle) automobile communication technology designed to allow automobiles to “talk” to each other. The systems will use a region of the 5.9 GHz band, the unlicensed frequency also used by WiFi.

Applications of Vehicular Communication Networks

  • Safety – Providing safety is the primary objective of vehicular communication networks. Vehicles who discover an imminent danger such as an obstacle inform others. Electronic sensors in each car can detect abrupt changes in path or speed and send an appropriate message to neighbors. Some of the immediate applications are:
    • Warnings on entering intersections.
    • Warnings on departing the highways
    • Obstacle discovery
    • Sudden halts warnings
    • Reporting accidents
    • Lane change warnings
  • Traffic Management & Road Traffic Safety – Traffic management is utilized by authorities to ease traffic flow and provide a real time response to congestions. Authorities may change traffic rules according to a specific situation such as hot pursuits and bad weather. Applications include:
    • Variable speed limits
    • Adaptable traffic lights
    • Automated traffic intersection control
    • Accommodating ambulances, fire trucks, and police cars
  • Driver Assistance Systems – Roadside units (RSUs) can provide drivers with information which help them in controlling the vehicle. Even in the absence of RSUs, small transmitters may be able to issue warnings such as bridge or tunnel height or gate width:
    • Parking a vehicle
    • Cruise control
    • Lane keeping assistance
    • Roadsign recognition
  • Information Services and Payments:
    • Toll collecting
    • Parking payments
    • Accessing Maps
    • Business locations
    • Car services
    • Gas stations
    • Web surfing
    • File downloads
    • Email
    • Gaming
  • Automated Highway Vehicle Control Systems – Using Automated Highway Vehicle Control System, In highways the vehicles are able to cruise without help of their drivers. This is done by cooperation between vehicles. For example each vehicle knows the speed and direction of travel of its neighboring vehicles through communication with them. The status is updated frequently, therefore each vehicle can predict the future up to some necessary time and is able to make appropriate decisions in appropriate time. Because automated highways are not limited by human response time, much higher speeds will be possible. This application is virtually impossible without utilizing vehicular communication networks.