US Patent 7853405 Intervehicle communication system

A driving support system for use in a vehicle uses a headlight controller for directing a headlight beam on a road surface in an intersection when the vehicle stops at the intersection. Another vehicle simultaneously approaching the intersection detects the beam of the surface with an image sensor and processor of the driving support system. The system of the another vehicle sends back a vehicle ID signal to the stopping vehicle when a predetermined beam pattern is recognized by the processor. Then, the system uses a buzzer for notifying a driver of the stopping vehicle that the ID signal has been returned.