PURPOSE: To allow a road communication equipment to obtain correct information by preventing the generation of radio interference even if a beam is transmitted from a vehicle traveling in each lane at the time of transmitting data from a vehicle to the road communication equipment.

CONSTITUTION: An on-vehicle communication equipment 2 returns data with a timing corresponding to the assignation of a return time included in a signal received from the road communication equipment 1. Looking from the road communication equipment 1, beams are emitted with respectively different timings from vehicles traveling in the different lanes so that radio interference is not generated by the cause to simultaneously and mutually emit beams between vehicles. Thus, data smoothly and certainly communicate from the vehicle to the road communication equipment 1.