Patent ID: 8452643

Claim:
A method performed by one or more processors for detecting vehicles with trailers in a road toll system, which comprises at least one radio beacon for radio communication with radio onboard units (OBUs), the method comprising: electronically associating a vehicle with a vehicle OBU carried by the vehicle, in a database; electronically associating a trailer with a trailer OBU, in the database; establishing radio communications between a radio beacon and said vehicle OBU, and between the radio beacon and said trailer OBU, via radio signals; electronically evaluating said radio signals; and electronically detecting that said vehicle and said trailer are related to one another, when said evaluation of radio signals with the vehicle OBU and the trailer OBU indicates that said vehicle OBU and said trailer OBU are moving at a limited and constant distance from one another, wherein the radio beacons are DSRC radio beacons and the vehicle OBU and the trailer OBU are DSRC OBUs.