Arrangement of a magnetic coupling coil and a transponder circuit on a vehicle wheel

Abstract

The arrangement of a magnetic coupling coil () and a transponder circuit () on a vehicle wheel () allows wireless data communication with an interrogation circuit () arranged on a fixed structure of the vehicle on which the wheel is mounted so as to be able to rotate about at least one rotational axis (). The magnetic coupling coil is mounted coaxially to the rotational axis of the wheel and defines a closed loop. This coupling coil acts as an inductive coupling interface between an antenna coil () of the transponder and an excitation coil () of the interrogation circuit. This magnetic coupling coil comprises a loop portion () oriented such that the magnetic field () in the magnetic coupling coil, which is induced by a primary magnetic field () generated by the interrogation circuit excitation coil, is directed in this loop portion in a substantially perpendicular direction to the primary magnetic field. The antenna coil () of the transponder circuit, which is arranged in a winding () of the coupling coil loop portion, is oriented so that only the magnetic field induced in the coupling coil loop portion passes therethrough without being influenced by the primary magnetic field.