Patent ID: 7839271

Claim:
A driving assistance system for supplying information to a vehicle traveling on an infrastructure, the system comprising: a magnetic marking formed on or in the infrastructure and adapted to encode the information intended for said vehicle, said information being modifiable, a detection device comprising a plurality of magnetic sensors placed on board said vehicle to detect a total magnetic field comprising the magnetic field generated by said magnetic marking and to produce signals representing said total magnetic field, and a processing unit adapted to process said representative signals and to determine, on the one hand, a first distance between said vehicle and said magnetic marking, and, on the other hand, to decode the information encoded in said magnetic marking; wherein the plurality of magnetic sensors comprises at least three magnetic sensors; and wherein at least one of the first and second distances, and the information encoded in the magnetic marking, are determined by the processing unit on the basis of an estimation function comprising the comparison, by at least squares criterion, of the values read by each of the magnetic sensors (Mfxi, Mgxi, Mhxi) with the values of a standard response of said sensors (fxi, gxi, hxi) which is a function of the total magnetic field, and each of the positions of said magnetic sensors (xi), the estimated values of the distances and of the information being the values which best fit to said read values.