A driver assistance system for supplying information to a vehicle travelling on an infrastructure comprises an electromagnetic wave transmitter, an electromagnetic wave receiver and a processor. The electromagnetic wave transmitter on-board the vehicle comprises at least one transmitting antenna configured to transmit variable-frequency electromagnetic waves to reflectors installed in the infrastructure. The electromagnetic wave receiver on-board the vehicle comprises at least one receiving antenna configured to receive the electromagnetic waves reflected by the reflectors. The processor is configured to extract data representative of the distance between the reflectors and the vehicle from the electromagnetic waves reflected by the reflectors and captured by the electromagnetic waver receiver.
