V2V (vehicle-to-vehicle)  communication, a technology designed to  allow automobiles to “talk” to each other,  is critical to the autonomous car concept.  Vehicle-to-infrastructure (V2I) is an extension  of V2V and allows vehicles to communicate  with the roadside infrastructure.  Collectively V2V plus V2I are known as V2X.

V2I communication would allow vehicles  to share their positions, destinations and  intended routes with central stations to, for  instance, coordinate traffic lights according  to traffic density, making driving not  only safer but also more fuel efficient and  environmentally-friendly. A vehicle could  send out an alert as its wheels begin to skid  on a wet surface, warning drivers in other  vehicles. These simple messages would be  transmitted via dedicated short-range communications (DSRC) on spectrum reserved  for transportation safety. 

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