METHOD AND DEVICES FOR DETERMINING THE DISTANCE BETWEEN A RADIO BEACON AND A VEHICLE DEVICE

摘要

The invention relates to a method for determining the distance (a) between a radio beacon (2) and a vehicle device (11) passing in front of said radio beacon, in a road toll system (1). A signal (10) of a frequency having a known temporal profile is emitted. Said method consists of the following steps: the signal is captured in the other component (2, 11) when passing and the temporal profile of the frequency is recorded in relation to the known temporal profile; a modification in the recorded frequency profile (13;14) exceeding a first threshold value is detected; two distant wave zones in the frequency profile, lying temporally in front of and behind the detected modification, which displays a frequency modification below a second threshold value, are searched for; the recorded frequency profile is scaled in such a manner that the distance wave zones take the predetermined values; and said distance (a) from the scaled frequency path is determined. The invention also relates to radio beacons (2), installations and vehicle devices (11) for implementing the method.